Abstracts

399 - 30-day mortality following trauma and orthopaedic surgery during the peak of the SARS-CoV-2 pandemic; a multicentre regional analysis of 484 patients

P Karayiannis¹, V Roberts¹, R Cassidy², A Mayne³, D McAuley⁴, D Milligan⁵, O Diamond⁴

¹Craigavon Area Hospital, Trauma and Orthopaedics, Craigavon, United Kingdom, ²Musgrave Park Hospital, Outcomes Department, Belfast, United Kingdom, ³Ulster Hospital, Trauma and Orthopaedics, Belfast, United Kingdom, ⁴Royal Victoria hospital, Trauma and Orthopaedics, Belfast, United Kingdom, ⁵Altnagevlin Area Hospital, Trauma and Orthopaedics, Londonderry, United Kingdom

Introduction: Now in the deceleration phase of the SARS-CoV-2  pandemic the focus has shifted to how to safely reinstate elective operating.  Regional and specialty specific data is important to guide this decision-making process. This study aimed to review 30-day mortality for all patients undergoing orthopaedic surgery during the peak of the pandemic within our region.
 
Methods: This multicentre study reviewed data on all patients undergoing Trauma and Orthopaedic surgery in a region, from 18th March 2020 to 27th April 2020. Information was collated from regional databases. Patients were  SARS-CoV-2 positive if they had positive laboratory testing and/or imaging consistent with the infection. 30-day mortality was assessed for all patients. Secondly, 30-day mortality in fracture neck of femur patients was compared to the same time period in 2019.
 
Results: 496 operations were carried out in 484 patients. The overall 30-day mortality was 1.9%. 7 of the 9 deceased patients underwent surgery for a fractured neck of femur, (all ASA 3 or 4). Paradoxically, the mortality for neck of femur fracture was reduced in 2020 compared to 2019(3.4% versus 6%,p=0.2). 27 patients contracted SARS-CoV-2 in the peri-operative period and of these 4 patients died within 30 days(14.8%). 21 of the 27 patients in this group had a fractured neck of femur, 22 were over the age of 70(81.5%). 
 
Conclusions: Overall 30-day post-operative mortality in Trauma and Orthopaedic Surgery patients remains low at 1.9%. There was no 30 day mortality in patients ASA 1 or 2. Patients with significant co-morbidities, increasing age and ASA 3 or above remain at the highest risk. For patients with SARS-CoV-2 infection post-operative 30-day mortality was 14.8%. The reintroduction of elective services should consider individual patient risk profile (including for ASA grade). Effective post-operative strategies should also be employed to try and reduce post-operative exposure to the virus.

There is NO Conflict of Interest: Yes

365 - Population mobility and adult orthopaedic trauma services during the COVID-19 pandemic: fragility fracture provision remains a priority

C Brennan¹, C Scott¹, G Holland¹, M Powell-Bowns¹, M Gillespie¹, S Mackenzie¹, N Clement¹, A Amin¹, TO White¹, A Duckworth¹

¹Royal Infirmary Edinburgh, Trauma and Orthopaedics, Edinburgh, United Kingdom

Aims: This study aims to define the epidemiology of trauma presenting to a single centre providing all orthopaedic trauma care for a population of ∼ 900,000 over the first 40 days of the COVID-19 pandemic compared to that presenting over the same period one year earlier. The secondary aim was to compare this with population mobility data obtained from Google.

Methods: A cross-sectional study of consecutive adult (> 13 years) patients with musculoskeletal trauma referred as either in-patients or out-patients over a 40-day period beginning on 5 March 2020, the date of the first reported UK COVID-19 death, was performed. This time period encompassed social distancing measures. This group was compared to a group of patients referred over the same calendar period in 2019 and to publicly available mobility data from Google.

Results: Orthopaedic trauma referrals reduced by 42% (1,056 compared to 1,820) during the study period, and by 58% (405 compared to 967) following national lockdown. Outpatient and inpatient referrals reduced by 44% and 36% respectively, and the number of surgeries performed by 36%. The regional incidence of traumatic injury fell from 5.07 (95% confidence interval (CI) 4.79 to 5.35) to 2.94 (95% CI 2.52 to 3.32) per 100,000 population per day. Significant reductions were seen in injuries related to sports and alcohol consumption. No admissions occurred relating to major trauma (Injury Severity Score > 15) or violence. Changes in population mobility and trauma volume from baseline correlated significantly (Pearson’s correlation 0.749, 95% CI 0.58 to 0.85, p < 0.001). However, admissions related to fragility fractures remained unchanged.

Conclusion: The profound changes in social behaviour and mobility during the early stages of the COVID-19 pandemic have directly correlated with a significant decrease in orthopaedic trauma referrals, but fragility fractures remained unaffected and provision for these patients should be maintained.

There is NO Conflict of Interest: No

Disclosure: Scott: editorial board membership of BJJ and BJR, consultancy and grants/grants pending from Stryker Orthopaedics.
White: consultancy from Acumed, and grants/grants pending from Acumed and Smith & Nephew.
Duckworth: grants from Scottish Government Quality Improvement Grant, Smith & Nephew, and Acumed, and book royalties from Elsevier and Taylor & Francis.

417 - 30 Day Mortality Following Surgical Management of Hip Fractures During the COVID19 Pandemic: findings from a prospective multi-centre UK study

AM Narang¹, G Chan², A Aframian³, Z Ali¹, A Carr¹, H Goodier⁴, C Morgan³, C Park⁵, K Sugand⁵, T Walton⁶, M Wilson⁴, A Belgaumkar⁷, K Gallagher⁴, K Ghosh², C Gibbons³, A Keightley⁸, Z Nawaz⁹, C Wakeling², K Sarraf⁵, B Rogers⁶, W Kieffer¹

¹Surrey & Sussex Healthcare NHS Trust, Trauma and Orthopaedics, Redhill, United Kingdom, ²Western Sussex Hospitals NHS Foundation Trust, Chichester, United Kingdom, ³Chelsea and Westminster Hospital NHS Foundation Trust, London, United Kingdom, ⁴Poole General Hospital NHS Foundation Trust, Poole, United Kingdom, ⁵Imperial College Healthcare NHS Trust, London, United Kingdom, ⁶Brighton and Sussex University Hospitals NHS Trust, Brighton, United Kingdom, ⁷Surrey & Sussex Healthcare NHS Trust, Redhill, United Kingdom, ⁸Royal Surrey Hospital NHS Foundation Trust, Guildford, United Kingdom, ⁹Frimley Health Foundation Trust, Frimley, United Kingdom

Background: 30-day mortality of patients with hip fracture is well researched and predictive, validated scoring tools have been developed (Nottingham Hip Fracture Score, NHFS). COVID-19 has significantly greater mortality in the elderly and comorbid patients which includes hip fracture patients. Non-operative treatment is not appropriate due to significantly higher mortality and therefore these patients are often exposed to COVID19 in the peri-operative period. What is unclear is the effect of concomitant COVID-19 infection in these patients.

Methods: A multicentre prospective study across 10 sites in the United Kingdom (responsible for 7% of hip fracture patients per annum in the UK). Demographic and background information were collected by independent chart review. Data on surgical factors included American Society of Anesthesiologists (ASA) score, time to theatre, Nottingham Hip fracture score (NHFS) and classification of fracture were also collected between 1st March 2020 and 30th April 2020 with a matched cohort from the same period in 2019

Findings: Actual and expected 30-day mortality was found to be significantly different between 2020 COVID-19 positive (RR 3.00 95% CI 1.57-5.75, p<0.001), 3x higher for COVID19 positive patients with 30 deaths recorded within 30-days compared against the 10 expected from NHFS risk stratification.

Interpretation: COVID-19 infection appears to be an independent risk factor for increased mortality in hip fracture patients. Whilst non-operative management of these fractures is not suggested due to the documented increased risks and mortality, this study provides evidence to the emerging literature of the severity of COVID-19 infection in surgical patients and the potential impact of COVID-19 on elective surgical patients in the perioperative period.

There is NO Conflict of Interest: Yes

721 - Impact of COVID-19 on clinical outcomes for patients with fractured hip: a multicentre observational cohort study (NOF-COV19 Study)

D. Rasidovic¹, I. Ahmed², C. Thomas¹, P. Kimani³, P. Wall², K. Mangat¹,  ^. NOF-COV19 Study Collaborative⁴

¹South Warwickshire NHS Foundation Trust, Trauma and Orthopaedics, Warwick, United Kingdom, ²University Hospitals Coventry and Warwickshire, Trauma and Orthopaedics, Coventry, United Kingdom, ³University of Warwick, Warwick Medical School, Coventry, United Kingdom, ⁴Mulitcentre Observational Study, Trauma and Orthopaedics, England, United Kingdom

Background: There are reports of a markedly increased perioperative mortality in patients admitted to hospital with a fractured hip during the COVID-19 pandemic in USA, Spain and Italy. Our study aims to describe the risk of mortality among patients with a fractured neck of femur in England during the early stages of the COVID-19 pandemic.

Methods: We completed a multicentre cohort study across 10 hospitals in England. Data were collected from 1st of March till 6th of April 2020, in which the World Health Organisation declared COVID-19 to be a pandemic. Patients ≥60 years of age admitted with hip fracture and a minimum follow up of 30 days were included for analysis. Primary outcome of interest was mortality at 30 days post-surgery or post admission in non-operative patients. Secondary outcomes included length of hospital stay and discharge destination.

Results: In total, 404 patients were included for final analysis with a COVID-19 diagnosis being made in 114 (28.2%) patients. Overall, 30 day mortality stood at 14.4%. COVID-19 cohort experienced a mortality rate of 32.5% (37/114) compared to 7.2% (21/290) in the non-COVID cohort, p = <0.001. In adjusted analysis, 30 day mortality was greatest in patients who were confirmed to have COVID-19 (OR 5.64, CI 2.95-10.80, p = <0.001) with an adjusted excess risk of 20%, male sex (OR 2.69, CI 1.37-5.29, p = 0.004) and in patients with ≥2 co-morbidities (OR 4.68, CI 1.5 – 14.61, p = 0.008). Length of stay was also extended in the COVID-19 cohort, on average spending 17.6 days as an inpatient vs. 12.04 days in the non-COVID-19 group, p = <0.001.

Conclusion: This study demonstrates that patients who sustain a neck of femur fracture in combination with COVID-19 diagnosis have a significantly higher risk of mortality than would be normally expected.

There is NO Conflict of Interest: Yes

728 - A Comparative Review of 1004 Orthopaedic Trauma Patients: Before and During the COVID-19 Pandemic

K. Dayananda¹, S.T. Mercer¹, R. Agarwal¹, T. Yasin¹, R.W. Trickett¹

¹Cardiff & Vale University Health Board (University Hospital Wales & University Hospital Llandough), Trauma and Orthopaedic Surgery, Cardiff, United Kingdom

Aims: COVID-19 necessitated abrupt changes in trauma service delivery. We compare the demographic and outcomes of patients treated during lockdown, to a matched period from 2019. Findings have important implications for service development. 

Methods & Materials: A split-site service was introduced, with a COVID-19 free site treating the majority of trauma. Polytrauma, spinal and paediatric trauma, plus COVID-19 confirmed or suspicious cases were managed at another site. Prospective data on all trauma patients undergoing surgery at either site, between 16/03/2020 and 31/05/2020 was collated and compared with retrospective review of the same period in 2019. Patient, injury and surgical details, length of stay (LOS), COVID-19 status, and outcome were compared.

Results: There were 1004 urgent orthopaedic trauma patients (604 in 2019; 400 in 2020). Significant reductions in time to theatre and LOS stay were observed. COVID-19 positive status was confirmed in 4.5%. COVID-19 mortality was 1.8%. Day-case surgery comprised 47.5%, with none testing positive for or developing clinically significant COVID-19 symptoms requiring readmission, at a minimum of 17 days. 

Conclusion: The novel split-site service, segregating suspected or confirmed COVID-19 cases, minimised onward transmission and demonstrated improved outcomes regarding time to surgery and LOS, despite altered working patterns and additional constraints. Day-surgery pathways appear safe regarding COVID-19 transmission. Lessons learnt require dissemination and should be sustained in preparation for a potential second wave or the return of a “normal” non-COVID workload. 
Clinical Relevance:

• Segregation of COVID-19 suspicious or confirmed cases from the remainder of the trauma workload minimises opportunity for transmission. 
• Well-structured day surgery pathways appear safe regarding COVID-19 transmission, with important ramifications for the reintroduction of planned surgical care.
• A consultant delivered service (at the expense of planned surgical care) is effective at minimising the burden on hospital infrastructure.

There is NO Conflict of Interest: Yes

790 - Impact of COVID-19 on UK orthopaedic training during the 2020 pandemic season: a prospective cohort analysis

D. Bodansky¹, L. Thornton², N. Sargazi¹, M. Philpott¹, R. Davies³, J. Banks⁴

¹Merseyside Deanery, Liverpool, United Kingdom, ²Macclesfield Hospital, Cheshire, United Kingdom, ³Central Manchester University Hospitals NHS Foundation Trust, Manchester, United Kingdom, ⁴Liverpool Foundation Trust, Liverpool, United Kingdom

Background: Drastic restructure of the NHS was undertaken in response to the pandemic with alterations to service delivery introduced from March 2020, which has impacted surgical training programmes. Here we quantify the impact of the COVID-19 pandemic on postgraduate Orthopaedic training.

Methods: A prospective study was undertaken between 16th March-3rd May 2020   to capture alterations to training activity in response to the COVID-19 pandemic. Data was collected regionally by all Trauma and Orthopaedic specialist registrars on the Health Education North West, West Sector (HENW West Sector/ Mersey) training programme using a live online electronic proforma.

Results: A total of 1,018 entries were analysed, from 10 hospitals, with a median of 21 (IQR 17.5-26) entries per trainee. Altogether, 382 elective and 169 trauma lists were cancelled during the study period in addition to 155 elective and 132 fracture clinics. Seven trainees self-isolated during this period, losing 39 sessions. All nine candidates due to sit the Fellowship of the Royal Colleges of Surgeons (FRCS) were cancelled. Trainees were redeployed to other specialties in 231 (22.7%) of entries, with altered duties undertaken within intensive care (24.4%), accident and emergency (25.1%) and general medicine (50.3%). Trainees had no assigned alternative duties in 192 (18.9%) of sessions and provided 90 extra fracture clinics and 70 extra trauma lists during this period. Teaching and admin were logged for the remaining 8 entries.

Conclusion: The Covid-19 pandemic has resulted in a 43% reduction in overall training opportunities which must be addressed in order for trainees to achieve their CCT competencies.

There is NO Conflict of Interest: Yes

940 - Is it safe yet? Patient readiness and perceptions about returning to hospital for planned orthopaedic care.

S. Mercer¹, A. Kinghorn¹, T. Yasin¹, A. John¹, R. Trickett¹

¹Cardiff and Vale University Health Board, Trauma & Orthopaedics, Cardiff, United Kingdom

Objectives: To investigate patient perceptions concerning attendance for planned orthopaedic surgery during the COVID-19 pandemic.

Design: Cross-sectional study.

Setting: Secondary and tertiary orthopaedic care.

Participants: 250 adult patients from the top of the elective orthopaedic waiting list at Cardiff and Vale University Health Board.

Interventions: Patients were telephoned between 25th May and 3rd June 2020 whilst lockdown remained in force in Wales. They were taken through a COVID-19 screening tool based upon British Orthopaedic Association guidance and stratified into one of four risk categories for their outcome following potential COVID-19 infection. Having shared this information a discussion was held to determine patients’ willingness to proceed with surgery. Reasoning was explored with those who chose to decline or defer.

Primary and Secondary Outcome Measures: Primary: Patients’ willingness to proceed with surgery. Secondary: Patient risk stratification.

Results: In total, 196 patients met the inclusion criteria and responded. Mean age of respondents was 57.4, varying significantly between subspecialties. There were 129 patients willing to attend for surgery, leaving over a third of those contacted wishing to cancel or defer. The most frequent reason given for not wishing to attend was fear of contracting COVID-19. There was a statistically significant difference in the willingness to proceed observed with increasing clinical risk (χ2(3) = 50.073, p=.000) with almost double the expected count of patients unwilling to proceed in the high and very high risk groups.

Conclusions: This study illustrates the variable and personal decisions patients are making regarding orthopaedic care due to COVID-19. It highlights the need for radical change to departmental processes regarding patient prioritisation upon the recommencement of planned surgical lists. However, it also reconfirms the vital importance of regular communication and shared decision making between a well-informed patient and a holistic orthopaedic team.

There is NO Conflict of Interest: Yes

1174- IMPACT-Restart: the influence of COVID-19 on postoperative mortality and risk factors associated with SARS-CoV-2 infection after orthopaedic and trauma surgery

A. Hall¹, N. Clement¹, N. Makaram², P. Robinson², R. Patton³, A. Duckworth¹, M. Moran², G. Macpherson⁴, P. Jenkins⁵

¹University of Edinburgh, SORT-IT / Dept of Orthopaedics & Trauma, Edinburgh, United Kingdom, ²University of Edinburgh, Dept of Orthopaedics & Trauma, Edinburgh, United Kingdom, ³NHS Lothian, Edinburgh, United Kingdom, ⁴NHS Lothian, Department of Orthopaedics and Trauma, Edinburgh, United Kingdom, ⁵Glasgow Royal Infirmary, SORT-IT / Dept of Orthopaedics & Trauma, Glasgow, United Kingdom

The primary aim of this study was to assess the independent association of COVID-19 on postoperative mortality for patients undergoing orthopaedic and trauma surgery. The secondary aim was to identify factors that were associated with developing COVID-19 during the postoperative period.

A multicentre retrospective study was conducted of all patients presenting to nine centres over a 50-day period during the COVID-19 pandemic (1st March to 19th April 2020) with a minimum of 50-days follow up. Patient demographics, ASA grade, priority (urgent or elective), procedure type, COVID-19 status and postoperative mortality were recorded.

During the study period 1659 procedures were performed in 1569 patients. There were 68 patients that were diagnosed with COVID-19. There were 85 deaths postoperatively. Patients that had COVID-19 had a significantly lower survival rate when compared to those without a proven SARS-CoV-2 infection (67.6% versus 95.8%, p<0.001). When adjusting for confounding variables a diagnosis of COVID-19 was associated with an increased mortality risk (hazard ratio 1.89, 95% confidence intervals (CI) 1.14 to 3.12, p=0.014). Sixty-two patients had COVID-19 postoperatively of which two were in the elective and 60 were in the urgent group. Regression analysis demonstrated an age >77 years (odds ratio (OR) 3.16, p=0.001), increasing ASA grade (OR 2.74, p<0.001), hip (OR 4.56, p=0.008) and periprosthetic (OR 14.70, p<0.001) fractures were associated with developing postoperative COVID-19.

Patients at risk of developing postoperative COVID-19 (patients >77years, increasing morbidity, sustaining a hip or periprosthetic fractures) may benefit from shielding to prevent them from infection that resulted in nearly twice the postoperative mortality rate, which is recognised to be higher in this frail group of patients.

There is NO Conflict of Interest: Yes

1238 - Efficacy of Surgical Helmet Systems for Protection Against COVID-19: A Double-Blinded Randomised Control Study

G. Schaller¹, S.K. Nayar¹, M. Erotocritou¹, A. Overton¹, T. Stelzhammer¹, O. Berber¹

¹Whittington Health NHS Trust, Trauma and Orthopaedics, London, United Kingdom

Background: Surgical helmet systems are used in elective orthopaedic surgery to reduce the risk of infectious agent transfer from surgeon to patient. There has been debate as to whether they provide additional protection to the surgeon from respiratory droplet borne pathogens. The aim of this study was to assess whether these helmet systems delivered additional benefit or pose potential risks to the surgeon.

Methods: A double-blinded randomised controlled study was undertaken investigating the efficacy of the Stryker Flyte Surgical Helmet as protection against respiratory droplets. The helmet systems were tested using a validated qualitative test, whereby the participant is exposed to a nebulised saccharin solution protocol whilst wearing the apparatus. A positive taste test indicates failure of the equipment. 35 tests were undertaken in accordance with a power analysis and following randomisation, 20 were allocated to the saccharin group with 15 to placebo. Taste tests were performed with the helmet fan turned on and off. Chi squared and Student’s t-test analysis of results were undertaken.

Results: Surgical helmets did not protect against the tasting of saccharin with a significant statistical difference between the saccharin and placebo cohort (p<0.0001). Within the saccharin cohort, 40% had a positive taste test with the fan on and 100% with the fan off.
There was a statistically different mean time to taste saccharin (p=0.049) when comparing the surgical helmets with their fan on (123.5 seconds, r=34-200 seconds) and off (62.6 seconds, r=20-160 seconds).

Conclusion: Current surgical helmet systems do not protect against aerosol borne particulate and therefore COVID-19. Such systems may increase risk to the surgeon by drawing in particulate and delay the recognition of intraoperative cues that point to respirator mask leak.

There is NO Conflict of Interest: Yes

1299 - Waiting for treatment with major joint arthritis in the era of COVID-19 can be ‘worse than death’. Elective arthroplasty waiting lists in COVID-19

J. Morris¹, T. Ashdown¹, D. Huntley¹, S. McKeon¹, W. Harland¹, J. Super¹, R. Anakwe¹

¹Imperial College Healthcare Trust, Trauma and Orthopaedic Department, London, United Kingdom

Aims: We undertook a study to evaluate the health status and quality of life for patients referred to our outpatient orthopaedic service with symptomatic major joint arthritis and for consideration of surgery whose appointments had been cancelled or deferred as a result of the response to the COVID-19 pandemic.
 
Patients & Methods: We identified 210 eligible adult patients referred to our elective orthopaedic service between 18 March 2020 and 13 May 2020.  These patients had scheduled first appointments with the orthopaedic service at the height of the pandemic and these appointments had been cancelled or deferred. Patients were invited to complete a telephone interview to assess their health status and quality of life using the EQ-5D-5L questionnaire.
 
Results: 111 (52.3%) patients agreed to participate in this study. Of these, 79 (71.2%) patients reported that their health status had deteriorated since they were referred to the service and had been awaiting assessment. There was a statistically significant correlation between the EQ-Visual Analogue Score (p = 0.007) and mean EQ-5D index score (0.420 (±0.285 SD) P = 0.000) in those patients who self-reported deterioration in health status since they were first referred for outpatient assessment.
 
Discussion: Our study showed that patients who are awaiting their assessment and treatment for symptomatic joint arthritis report measurable impairment of their health status, quality of life and deteriorate whilst they wait. A particular subset of patients evaluate their status as ‘worse-than-death’. Waiting lists are not benign and in establishing the recovery programme following the COVID-19 pandemic it is important that the impact of delayed treatment for this particular group of patients is not underestimated.

There is NO Conflict of Interest: No

1371 - The Impact of COVID 19 on the Management and Outcomes of Patients with Proximal Femoral Fractures: a Multi-centre Study of 580 Patients.

V. Giannoudis¹, A. Jimenez¹, C. De², A. Wignall³, S. Sturdee¹, P. Giannoudis³, H. Pandit⁴, A. Gulat², J. Palan⁵

¹Huddersfield Royal Infirmary, Trauma & Orthopaedics, Huddersfield, United Kingdom, ²Sandwell and West Birmingham Hospitals NHS Trust, Trauma & Orthopaedics, Birmingham, United Kingdom, ³Leeds General Infirmary, Trauma & Orthopaedics, Leeds, United Kingdom, ⁴LIRMM University of Leeds, Trauma & Orthopaedics, Leeds, United Kingdom, ⁵Leeds Teaching Hospital NHS Trust, Trauma & Orthopaedic Surgery, Leeds, United Kingdom

Background: In March 2020, the World Health Organisation declared the COVID-19 outbreak a pandemic. Multiple new guidelines were proposed and existing models of social, domestic and hospital care altered. This study aimed to assessing the impact of COVID-19 on the demographics, presentation and clinical management of patients with proximal femoral (hip) fractures.
 
Methods: This retrospective multicentre cohort study compared all patients admitted with hip fractures, between 1st March and 30th May in 2019 (Group PC: Pre-COVID) with hip fracture patients admitted over the same time period during the pandemic in 2020 (Group C: COVID). The data was obtained from hospitals’ local and National Hip Fracture Databases. Primary outcomes were time to theatre, in-patient length of stay and 30-day mortality.
 
Results: In total there were 580 patients identified in the PC (n=304) and C group (n=276).
There were no significant differences in the numbers of DHS (75 [PC] vs 71 [C], p=0.770) and hemiarthroplasties (110 [PC] vs 110 [C], p=0.363) performed. There was a significant reduction in percentage of THRs (11% to 5%, p=0.006) and an increase in those managed conservatively (1% to 5%) in group C (p=0.002). The time to theatre (hours) was significantly longer in Group C (43.7) Vs Group PC (34.6) (p=0.0009). Length of hospital stay was similar in both groups (16.6 [PC] Vs 15 [C], p=0.0891). 30-day mortality rate for both cohorts was 8% (p=0.828). For COVID positive patients, it was significantly higher 35.3% Vs 5.4% (COVID negative) (p<0.0001) in Group C.
 
Conclusions/ Findings: This is the largest literature series, examining the impact of the COVID-19 pandemic on hip fracture patients. The COVID-19 pandemic and subsequent hospital restructuring has had major effects on time to theatre and poses very high 30-day mortality rates for COVID positive hip fracture patients. 

There is NO Conflict of Interest: Yes

1938 - Urgent Bone and Soft tissue sarcoma surgery during the COVID19 pandemic; the experience from seven UK centres; a BOOS study

T.D. Cosker¹, R.B. Rajasekaran¹, D. Whitwell¹, C.L. Gibbons¹, R. Ashford¹

¹Nuffield Orthopaedic Centre, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, Oxford, United Kingdom

Purpose: Deferring cancer surgeries can have devastating complications including patient mortality. During the unprecedented COVID-19 pandemic, departmental re-organisation and adherence to guidelines enabled expeditious surgical care for patients with primary and malignant bone and soft tissue tumour (BST) patients. We analyzed the outcomes of surgeries on BST during the first two months of the pandemic across seven sarcoma centers in UK.

Materials & methods: Between March 12th 2020 and May 20th 2020, 283 patients of a median age of 59 years (18-87) underwent surgery across seven sarcoma centres in the UK for primary and metastatic bone tumours and urgent soft tissue sarcomas. The decision to operate was made in conjunction with guidelines issued by the NHS, British Sarcoma Group (BSG) and the British Orthopaedic Oncology Society (BOOS) and on patients who were deemed to benefit most from surgery.

Results: At a minimum follow-up of 30 days post-surgery, 274 patients (96.8%) were recovering well post-surgery. Fifty-six patients (19.7%) had post-operative complications which included 9 patients (3.1%) developing pulmonary embolism. The majority of complications (48/56 = 85.7%) occurred in ASA III and ASA IV category patients. Seven patients (2.4%) contracted COVID-19 and out of those, 5 patients required escalation of care due to pulmonary complications and 4 patients (1.4%) died. Patients less than 60 years of age had lesser complications than those above 60 years (p<0.001).

Conclusion: Our results show that favorable outcomes are possible following BST surgeries even during the COVID-19 pandemic. Surgery in patients less than 60 years and in ASA I&ASA II category are associated with better and safer outcomes. Intentional postponement of surgery in patients with co-morbidities and above 60 years must be considered if we encounter a further peak of the disease in future or a similar unprecedented challenge. All primary bone and soft tissue units across the UK have risen to the challenge of making complex decisions during periods of exceptional strain and have developed safe and robust systems to triage these patients.

There is NO Conflict of Interest: Yes

372 - The financial burden of COVID-19 on trauma theatre efficiency at a major trauma centre

T Packer¹, A Davies¹, T Ashdown¹, S Sabharwal¹, P Reilly¹

¹Imperial NHS Trust, T&O Dept, London, United Kingdom

Introduction: The COVID-19 Pandemic has caused major disruption to the delivery of care across the National Health Service (NHS). Surgical pathways have been adapted to ensure the safety of staff and patients. The aim of this study is to access the financial implications of inefficiencies caused by changes to trauma operating at a major trauma centre.

Design: Time Driven Activity Based Costing analysis.

Setting: Single major trauma centre

Method: Inefficiency costs are defined as staffing costs and overheads for the time in operating theatres where there is no patient contact (NPC). Patient contact is inclusive of anaesthetic and operative time. Data was collected for a trauma theatre for a six week period pre- and post- the onset of COVID-19. Staffing cost were extract from national pay scales.

Results: The average number of cases per day were 2.6 pre-COVID and 1.9 post-COVID. Pre COVID the average NPC time was 1hrs 41minutes per day. Post-COVID the NPC time increased to 5hrs 13minutes. The extra cost of additional NPC time including estimated overhead costs, was a mean of £1,269.36. With two trauma theatres during weekdays, and a single theatre at weekends, we usually have a total of 625 theatre days a year. Total additional cost of inefficiency and staffing for 3 extra hours, would be estimated at £1,438,311.88 a year.

Discussion: We found theatre inefficiency increased considerably and demonstrated a sizeable financial annual burden which is likely to impact on hospital economies across the UK. We recommend an uplift to tariffs during the COVID-19 pandemic period to help support costly but safe surgical practices.

There is NO Conflict of Interest: Yes

397 - The effects of Covid-19 on perioperative morbidity and mortality in patients with hip fractures: A multi-centre cohort study

B Kayani¹, E Onochie², F Begum³, V Patil⁴, R Cuthbert⁵, D Ferguson⁶, J Bhamra⁷, A Sharma⁸, P Bates⁹, F Haddad³

¹University College London Hospital and Royal London Hospital, London, United Kingdom, ²Newham General Hospital and Whipps Cross Hospital, London, United Kingdom, ³University College London Hospital, London, United Kingdom, ⁴Basildon University Hospital, Basildon, United Kingdom, ⁵Queens Hospital, Romford, United Kingdom, ⁶King George Hospital, Illford, United Kingdom, ⁷Wexham Park Hospital, Slough, United Kingdom, ⁸Hillingdon Hospital, Uxbridge, United Kingdom, ⁹Royal London Hospital, London, United Kingdom

Background: The objectives of this study were to establish the effects of Covid-19 on perioperative morbidity and mortality, and determine any risk factors for increased mortality in patients with Covid-19 undergoing hip fracture surgery.

Methods: This multicentre cohort study included 340 coronavirus negative patients versus 82 coronavirus positive patients undergoing surgical treatment for hip fractures across nine NHS hospitals within Greater London, United Kingdom. Predefined study outcomes relating to patient demographics, fracture configuration, operative treatment, perioperative complications and mortality were recorded by observers using a standardised data collection proforma. Univariate and multivariate analysis were used to identify risk factors associated with increased risk of mortality.

Results: Coronavirus positive patients had increased risk of postoperative complications (89.0% vs 35.0%, p<0.001), higher rates of admission to high dependency and intensive care units (61.0% vs 18.2%, p<0.001), and increased length of hospital stay (13.8 ± 4.6 days vs 6.7 ± 2.5 days, p<0.001) compared to coronavirus negative patients. Postoperative complications in coronavirus positive patients included respiratory infections (13.4%), thromboembolic disease (13.4%), acute kidney injury (12.2%), and multi-organ dysfunction (12.2%). Coronavirus positive patients had increased risk of postoperative mortality (30.5% vs 10.3%, p<0.001) compared to coronavirus negative patients, with positive smoking status (Hazard ratio: 15.4 (95% CI: 4.55-52.2, p<0.001) and more than three comorbidities (Hazard ratio: 13.5 (95% CI: 2.82-66.0, p<0.001) associated with increased risk of mortality.

Conclusion: Surgery in coronavirus positive patients was associated with increased length of hospital stay, more admissions to the critical care unit, higher risk of perioperative complications and increased mortality compared to coronavirus negative patients. Multivariate analysis revealed that smoking and multiple (>3) comorbidities were associated with increased risk of postoperative mortality.

Implications: Neck of femur surgery in patients with Covid-19 is associated with increased morbidity and mortality. Smoking and >3 comorbidities are risk factors for increased mortality in these patients.

There is NO Conflict of Interest: No

549 - Managing Patients with Fragility Fractures of the Femur During the COVID-19 Pandemic: The Experiences of Two London Hospitals

C. Porte¹, F. Wong¹, C. Smith¹, V. Dorrell¹, J. Simms¹, T. White¹

¹Lewisham and Greenwich NHS Trust, London, United Kingdom

The COVID-19 global pandemic has disrupted healthcare services worldwide. People who suffer from a fragility fracture of the femur are usually in the high-risk age bracket for COVID-19 related death.

The aim of our study was to assess the impact of the COVID-19 pandemic on patients presenting with fragility fractures of the femur. The primary outcome measure was 30-day mortality. Secondary outcome measures included the National Hip Fracture Database (NHFD) 6 Key Performance Indicators (KPIs).

Retrospective analysis of prospectively collected data was performed for all 96 patients presenting to the Lewisham and Greenwich NHS Trust with a fragility fracture of the femur between 01/02/20 and 30/04/20. Patients were classified as COVID-C (confirmed), COVID-S (suspected) or COVID-N (negative) for subgroup analysis. All patients were followed up for a minimum of 30 days or until death. Outcomes were compared to data extracted from the NHFD for the same time period in 2018 and 2019.Twelve patients had positive swab results (COVID-C), 44 patients had strong clinical or radiological evidence of COVID-19 without positive swab results (COVID-S) and 40 patients had no evidence of COVID-19 infection (COVID-N). The 30-day mortality rate was 12.5% and overall morality during the study was 16.7%. The COVID-C group had an overall mortality rate of 50%, significantly higher than the other groups. COVID-N patients had a significantly shorter length of stay in hospital (mean 10.6 days vs 13.9 days). Logistic regression analysis found COVID-19 positive swab and admission haemoglobin <12g/dL contributed significantly to mortality with an odds ratio of 5.88 and 4.38 respectively (p = 0.016).

All of our KPIs were maintained at levels comparable to previous years, if not improved, therefore the increase in mortality is attributed to COVID-19. An accelerated care pathway may reduce mortality rates in this vulnerable patient group should subsequent outbreaks of COVID-19 occur.

There is NO Conflict of Interest: Yes

571 - The impact of the Coronavirus Disease (COVID-19) crisis on surgical training: A global survey and a proposed framework for recovery

M. Yiasemidou¹, J. Tomlinson², C. Lewis³, I. Chetter¹, S. Biyani³

¹Hull Royal Infirmary, Hull, United Kingdom, ²Sheffield Teaching Hospitals, Sheffield, United Kingdom, ³Leeds Teaching Hospitals, Leeds, United Kingdom

Introduction: SARS-Cov-2 has had a profound worldwide impact over the last six months, with the World Health Organisation declaring a pandemic on March 11th 2020.  Radical changes were made to the running of surgical services worldwide, to reduce the risk of peri-operative illness in patients undergoing non-urgent surgery. This also allowed redeployment of staff to work in other areas of hospitals. These changes have had a profound impact on surgical services, and thus training opportunities.

Methods: A cross-sectional, web-based survey was conducted. This was designed by the steering committee and validated prior to dissemination.

Results: 608 responses were obtained by thirty-four countries and fifteen specialties. The results demonstrated great disruption in all aspects of training. The impact was higher for conferences (525/608), hands-on courses (e.g. simulation) (517/608), less for in-patient care (268/608) related training. Training in Australia and Asia was affected less than in Europe (P-value<0.001)
Alternative resources (webinars: 359/608, educational videos: 234/608), have developed rapidly, interestingly trainees express some dissatisfaction with them for a variety of reasons, with accessibility and hardware issues the most common problems.
A five-pillar framework for training recovery is proposed: (1) Prioritise trainee and public safety (2) Guidance from training stakeholders – involvement of trainees (3) Prioritise training – the role of senior surgeons/trainers (4) Providing access to alternative/new teaching methods and (5) Addressing trainee anxiety.

Conclusion: Training has been disrupted to a great degree. Introduction of new teaching methods and focus on training after the pandemic are imperative for trainees to make up for lost time.

Implications: COVID-19 has significantly disrupted training, and may continue to do so for a significant period of time. Urgent discussion is needed to minimise the impact on training and trainee wellbeing.

There is NO Conflict of Interest: Yes

609 - COVID-19: The effects of a UK national lockdown on the workload in a regional hand trauma unit

J. Murray¹, M. Hampton², M. Clark², I. Baxter², R. Stevens¹, E. Flatt¹, K. Wembridge², M. Birks¹

¹Sheffield Teaching Hospitals, Sheffield, United Kingdom, ²Rotherham NHS Foundation Trust, Rotherham, United Kingdom

Introduction: On the 23rd of March 2020 the UK government issued requirements for a national lockdown to slow the spread of COVID-19 and reduce hospital admissions. The aim of this study was to determine the impact lockdown had on hand trauma attendances at a regional hand trauma unit.
 
Patients and Methods: A retrospective analysis was performed at a regional hand trauma unit. Data was collected from the first 2 weeks of lockdown in the UK (23/03/20–07/04/20), and compared with the corresponding 2-week period in 2019. The total number of referrals to a hand specialist, the mechanism of injury and the types of injury were recorded.
 
Results: There was a 61.5% (50 lockdown Vs 130 2019) reduction in attendances to the hand unit. We observed a significant change in the mechanisms of injury involved in sustaining hand injuries. There was a substantial increase in the proportion of DIY/garden related injuries (26% lockdown Vs 8.5% 2019) and animal bites (14% lockdown Vs 5% 2019) during lockdown. This change in mechanism of injury also led to a change in the injury types treated. We saw a significant increase in nerve injuries requiring nerve repair (12% lockdown Vs 2.3% 2019) and hand infections requiring surgical drainage and/or admission for intravenous antibiotics (24% lockdown Vs 6.2% 2019) during lockdown. Crush injuries and sports related injuries reduced, as did fractures of the hand. There was no difference in injuries caused by assaults/punches, falls, or accidental lacerations sustained at home
 
Conclusions: The national lockdown dramatically reduced the incidence of hand injury attendances. The incidence of DIY injuries and animal bites increased, leading to comparatively more significant nerve injuries and infections requiring treatment.

There is NO Conflict of Interest: Yes

717 - Increased proportion of alcohol related trauma in a South London major trauma centre during lockdown, a cohort study

O.S. Brown¹, P. Tsinaslanidis¹, C.B. Hing¹

¹St George's University Hospitals NHS Foundation Trust, Trauma and Orthopaedics, London, United Kingdom

Background: Alcohol has been implicated in 10-35% trauma admissions and up to 40% trauma-related deaths globally. Alcohol intoxication is linked to an increased risk of trauma, with violent crime associated with consumption. In response to the Covid-19 pandemic, the United Kingdom (UK) entered a state of ‘lockdown’ on 23rd March 2020 with citizens largely expected to remain at home. Personal isolation, pub and restaurant closures, cancellation of sports, and financial stress are all expected to influence the pattern of alcohol-related trauma during lockdown, although this has not yet been quantified.

Methods: All patients over 16 years admitted as ‘trauma calls’ during April 2018 and April 2019 (pre-lockdown), and April-May 2020 (during lockdown) had electronic patient records (EPR) analysed. Patients’ blood alcohol level (BAC) combined with records of intoxication were used to identify alcohol-related trauma. Unpaired Student’s t tests and Pearson chi squared tests were performed using IBM SPSS v25.

Results: Alcohol-related trauma was present in a significantly higher proportion of adult trauma calls during lockdown (lockdown 60/191 (31.41%), versus pre-lockdown 62/316 (19.62%) X2=9.061, p=0.003). Lockdown was also associated with increased daytime and weekday admissions of alcohol related trauma (lockdown 30/60 (50.00%) versus pre-lockdown 17/62 (27.42%) X2=6.565 p=0.010); lockdown 36/60 (60.00%) vs 26/62 (41.94%) X2=3.981 p=0.046). Head or neck injuries were more common among alcohol-related trauma during lockdown (22/60 (36.67%) vs 14/62 (22.58%) X2=133.099, p<0.001). No significant difference existed between the age, gender, mechanism, or length of stay between pre-lockdown and lockdown cohorts.

Conclusion: UK lockdown was associated with an increased proportion of alcohol-related trauma at a London MTC. The weekly pattern of trauma was altered, but the demographics and associated mechanisms were not.

Implications: With the possibility of a global ‘second wave’ of Covid-19, a further lockdown may result in increased alcohol-related trauma.

There is NO Conflict of Interest: Yes

819 - Machine Learning continuous fall risk classification in an elderly population from inertial measurements during activities of daily living

K. Hewage^1,2, S. Fosker^1,2, S. Lee³, O. Armitage³

¹East Sussex Healthcare Trust, Hastings, United Kingdom, ²CUSH Health, Hastings, United Kingdom, ³BIOS Health, Cambridge, United Kingdom

Introduction: The COVID-19 global pandemic has highlighted the need for solutions to protect our most vulnerable members of society. Falls are one of the most common causes of injury in people over the age of 65, with one in ten falls resulting in a serious injury which can have life-threatening or life-altering consequences. However, fall risk assessment methods typically require specific equipment or a specially trained clinician’s time, thus limiting their feasibility and frequency. Therefore, there is a need for monitoring systems that can use motion from daily activities to bridge the gap between the clinic and everyday life, continuously assessing fall risk without clinician intervention.

Methods & Results: A pilot study to train and test a remote monitoring system. Wearable inertial measurement unit (IMU) data, and online real-time Machine Learning, to an elderly patient population for automatic, continuous and high-accuracy fall risk estimation. Participants then carried out a series of stereotypical activities of daily living such as walking, sitting down and getting out of bed. The fall risk classifier is a gradient boosting classifier that was trained on selected segments of the IMU data (e.g. walking or transitional segments). The most accurate model used walking data from the hip-mounted sensor to achieve an accuracy of 87.5% with 88.9% sensitivity and 88.9% specificity, which is comparable to the most accurate classifiers in the literature.

Conclusion: This work validates the potential of an inertial measurement-based system that uses meaningful segments from freely moving data to classify elderly fall risk. Fall risk is a holistic metric which encompasses comorbidities, adverse events and living conditions; the aim of this system is to extract relevant gait information, and in the future combine it with other information about an individual to accurately assess their fall risk.

There is NO Conflict of Interest: Yes

842 - COVID 19 and Trauma and Orthopaedic telephone clinics – how this pandemic has changed the world of clinics. A single centre experience

M. Raad¹, S. Ndlovu¹, D. Neen¹

¹Darent Valley Hospital, Trauma & Orthopaedics, Dartford, United Kingdom

Background: Our department runs a number of elective and fracture clinics with about 70 – 100 new referrals and follow-up patients on a daily basis. Overbooked clinics, staff and resource constraints are ongoing challenges. During the COVID 19 pandemic our aim was to minimise exposure, to protect staff and patients. Therefore, on a daily basis clinic lists were analysed and only patients requiring a physical appointment were brought in, all other patients had a telephone clinic.

Method: In this study we retrospectively compared two groups of patients: those seen in traditional clinics pre-COVID 19 and those who had telephone clinics during the COVID-19 pandemic. We had a cohort of 60 patients in each group with various Orthopaedic complaints; both groups had elective and trauma patients. We compared four clinical parameters; the ability to reach a definitive clinical diagnosis and treatment plan, the necessity of a clinical examination, and outcomes from the consultation.

Results: Clinicians were able to make a definitive diagnosis in 93% of patient during telephone clinics compared to 83% in face to face clinics. 92% of patients from telephone clinics did not require examination to reach a diagnosis, 97% of patients from telephone clinics had a definitive plan compared to 92% in traditional clinics. However traditional clinics had a superior discharge rate at 56% compared to 30% for telephone clinics.

Conclusion: Face to face clinics have always been the gold standard in the management of both trauma and elective patients in Trauma and Orthopaedics. COVID-19 presented us with a chance to show that telephone clinics are equally effective, and may be superior to traditional clinics in a specific set of patients. Further studies should be performed to confirm our findings and investigate cost-effectiveness. We should prepare to adapt to using telephone clinics on a regular basis in the future.

There is NO Conflict of Interest: No

867 - “Sedate, Straight, No Wait” - Mini C-Arm; Lessons Learnt from the COVID-19 Pandemic

T. Cash¹, N. Sargazi¹, C. Barton¹, N. Boyce-Cam¹

¹Mid Cheshire Hospitals NHS Foundation Trust, Trauma and Orthopaedics, Crewe, United Kingdom

Background: The COVID-19 pandemic has altered the management of acute orthopaedic injuries with focus on avoiding unnecessary admissions. At the start of the pandemic, the trust’s mini c-arm was relocated to fracture clinic where manipulations were performed at the point of presentation. We aim to highlight the clinical and financial impact of this intervention.

Methods: Data was collected prospectively regarding the number of manipulations undertaken in fracture clinic between 03/04/20 to 01/05/20 and compared to the same period in 2019. All clinicians completed IR(ME)R training. A standard operating procedure was written to guide administration of analgesia for both paediatric and adult cases. Essential bedside monitoring, resuscitation equipment and senior ED doctor support (airway trained) were made available to ensure patient safety.

Results: The mini c-arm was used on 34 patients, mean age 46 years (range 2-92). The majority were upper limb injuries (88.2%). Manipulations using the mini c-arm were performed in 70.1% with 15 patients (44.1%) avoiding admission for theatre. Only 1 patient (2.9%) required repeat manipulation and k-wiring in theatre for a displaced paediatric supracondylar fracture. No adverse events were recorded. Compared to 2019, the total number of patients requiring manipulation in theatre decreased by 66.7% with an 88.9% reduction in upper limb manipulations. NHS references costs from 2018-19 were used to calculate a potential cost saving of £8445 over the 28-day period.

Conclusion: Utilisation of a mini c-arm in the fracture clinic setting reduces the need for manipulations in theatre and avoids unnecessary hospital admission for patients. This reduces the burden on trauma lists, decreases time to definitive treatment and minimises nosocomial COVID-19 transmission. This model is both a safe and cost-effective method of providing definitive orthopaedic care, which can be used by other trusts for service planning during the ongoing pandemic and beyond.

There is NO Conflict of Interest: Yes

899 - The experience of patients with traumatic injuries and urgent orthopaedic conditions during the coronavirus pandemic treated via a ‘one stop shop’ T+O-led minor injuries unit

S. Howles¹, T. Mahmood¹, S. Lala¹, A. Pearse¹, C. Docker¹

¹Worcestershire Acute Hospitals NHS Trust, Worcester, United Kingdom

Background: In line with the British Orthopaedic Association guidance on the management of patients with traumatic injuries and urgent orthopaedic conditions during the coronavirus pandemic, the orthopaedic team at Worcester Royal Hospital set up a ‘one-stop-shop’ minor injuries clinic (MIU) for the management of minor injuries.   This seven-day service provided a direct pathway to trauma clinic for patients who would usually be managed in the ‘minor injuries’ stream within the emergency department.  

Aims: The aim of this project was to evaluate the service we provided, and to audit local outpatient management of trauma and orthopaedic patients during the Covid 19 pandemic against the guidance set out by the BOA in the Covid-specific ‘BOAST’: 'Management of patients with traumatic injuries and urgent orthopaedic conditions during the coronavirus pandemic.'

Methodology: Data was collected retrospectively from several sources including a database kept by clinic staff, dictated clinic letters and scanned patient notes. Data collected included patient age and gender, time of arrival and departure, grade of the reviewing clinician, diagnosis, management and the outcome of clinic attendance, including timing of follow up. The data collection period was over 6 weeks from 20/04/2020 to 01/06/2020.

Results: 700 patients were seen in MIU over the 6 week data collection period. 98% of patients were seen by middle grade or consultant and 85% were seen and treated within an hour. 71% of patients were discharged from their first appointment, and only 9 patients (1%) required a fracture clinic appointment within 72 hours. A total of 15 patients (2%) reattended, with just four of these requiring additional intervention.

Conclusions: We delivered a seven-day minor injuries service in which the majority of patients received consultant-led definitive management at first appointment, in keeping with BOA guidance. The lessons learned through this experience will inform future quality improvement activity.

There is NO Conflict of Interest: Yes

923 - The effect of COVID-19 lockdown on orthopaedic trauma: a multicentre study across Scotland

D. MacDonald¹, D. Neilly¹, P. Davies², C. Crome³, A. Lee⁴, G. Scicluna³, T. Ha⁵, C. Donoghue⁶, J. Bashyam¹, T. Greensmith², A. Faulkner², A. Macinnes², R. Pennington², M. Kennedy³, L. Guiot³, B. Wheelwright³, T. Noteman⁵, C. Harte⁵, M. Torkington⁵, B. Jamal³, S. Gill³, A. Jariwala², D. Boddie¹, I. Stevenson¹, G. Ashcroft^4,4

¹Aberdeen Royal Infirmary, Aberdeen, United Kingdom, ²Ninewells Hospital, Dundee, United Kingdom, ³Queen Elizabeth University Hospital, Glasgow, United Kingdom, ⁴University of Aberdeen, Aberdeen, United Kingdom, ⁵Glasgow Royal Infirmary, Glasgow, United Kingdom, ⁶Raigmore Hospital, Inverness, United Kingdom

Background: The UK government declared national lockdown on 23rd March 2020 to reduce transmission of COVID-19. The aim of this study was to identify the effect of lockdown on the rates, types, mechanisms and mortality of musculoskeletal trauma across Scotland.

Methods: Data for all musculoskeletal trauma requiring operative treatment was collected prospectively from five key orthopaedic units across Scotland during lockdown (23/03/2020-28/05/2020). This was compared with data for the same timeframe in 2018 and 2019. Data collected included all cases requiring surgery, injury type, mechanism of injury, and inpatient mortality.

Results: 1315 patients received operative treatment from 23/03/2020 – 28/05/2020 compared to 1791 in 2019 and 1719 in 2018. The numbers of all injury types decreased, but the relative frequency of hip fractures increased (36·3% (2020) vs 30·2% (2019), p<0·0001 & 30·7% (2018), p<0·0001). Significant increases were seen in proportion of DIY-related injuries (3·1% (2020) vs 1·7% (2019) ,p=0·01 & 1·6% (2018) ,p<0·01) and injuries caused by falls (65·6% (2020) vs 62·6% (2019), p=0·08 & 61·9% (2018), p=0·05). Significant decreases were seen in proportion of RTCs (2·6% (2020) vs 5·4% (2019), p<0·0001 & 4·2% (2018), p=0·02), occupational injuries, (1·8% (2020) vs 3·0% (2019), p=0·03 & 2·3% (2018), p=0·01) and infections (6·8% (2020) vs 7·8% (2019), p=0·27 & 10·3% (2018), p<0·01). Cycling injuries increased (78 2020 vs 64 2019 vs 42 2018). A significant increase in proportion of self-harm injuries was seen (1·7% (2020) vs 1·1% (2019), p=0·19 & 0·5% (2018), p<0·0001). Mortality of trauma patients was significantly higher in 2020 (4·9%), than in 2019 (3·2%,p=0·02) and 2018 (2·6%,p<0·0001).

Conclusion: The UK COVID-19 lockdown has resulted in a marked reduction of musculoskeletal trauma requiring surgery in Scotland. There have been major changes in types and mechanisms of injury, and concerningly mortality of trauma patients has risen significantly.

There is NO Conflict of Interest: Yes

965 - UK COST Study: The impact of COVID-19 on surgical training. A survey of 100 UK surgeons

H. Rajgor¹, M. Almajee¹, A. Rajgor², F. Hossain³, T. Moores³

¹Royal Orthopaedic Hospital, Birmingham, United Kingdom, ²Newcastle University, Newcastle, United Kingdom, ³Walsall Manor Hospital, Walsall, United Kingdom

Background: The coronavirus pandemic has had a significant impact on the UK medical workforce. The aim of the survey was to assess the impact of COVID-19 on surgical training in the UK from trainee surgeons’ perspectives.
 
Method: A cross-sectional descriptive survey was designed with 27 questions and sent to a representative sample distributed nationally via trainee collaboratives, surgical training programme directors and trainee societies. Significance was set at p<0.05.
 
Results: 100 responses were received including 64 from orthopaedic trainees. 77 respondents were male and 23 were female. The mean score of COVID-19 having an impact on surgical training was 8.94/10. No difference was demonstrated between senior and junior trainees. Trainees were concerned about achieving indicative elective and trauma numbers with a mean score of 7.94/10. Trainees were not happy to be re-deployed (p<0.01). Trainees were also concerned about achieving appropriate number of work based assessments with no difference between junior and senior trainees (p=0.10). No difference was shown between trainees regarding the impact of COVID-19 on mental health (p=0.97). Simulation and cadaveric training were alternate forms of training assessments recommended by trainees who were unable to achieve due to COVID-19 (p<0.05). 94% of trainees have performed less than 20 cases per month during the coronavirus pandemic.
 
Conclusion: COVID-19 has changed the training landscape for junior surgeons. Trainees are concerned about progression and achieving indicative numbers for elective and trauma cases. Simulation and cadaveric training could provide an alternative method for surgical training.

There is NO Conflict of Interest: Yes

1027 - Providing a paediatric trauma and orthopaedics service during the peak of the COVID-19 pandemic. The Royal National Orthopaedic Hospital experience

A.D. Iliadis¹, D.M. Eastwood¹, L. Bayliss², M. Cooper³, A. Gibson⁴, R. Hargunani⁵, P. Calder¹

¹Royal National Orthopaedic Hospital, Paediatric and Limb Reconstruction Unit, Stanmore, United Kingdom, ²Royal National Orthopaedic Hospital, Sarcoma Unit, Stanmore, United Kingdom, ³Royal National Orthopaedic Hospital, Anaesthetics Unit, Stanmore, United Kingdom, ⁴Royal National Orthopaedic Hospital, Spinal Unit, Stanmore, United Kingdom, ⁵Royal National Orthopaedic Hospital, Radiology Unit, Stanmore, United Kingdom

Background: In response to the COVID-19 pandemic, there was a rapidly implemented restructuring of UK healthcare services. The Royal National Orthopaedic Hospital became a central hub for the provision of Trauma Services for North Central/East London (NCEL) while providing a musculoskeletal tumour Service for South of England, Midlands and Wales and an urgent Spinal service for London. We review our practice over this period in order to share our experience and lessons learned. Our admission pathways are described and the safety of surgical and interventional radiological procedures performed under general anaesthesia (GA) with regards to COVID-19 in a paediatric population are evaluated.

Methods: All paediatric patients (≤16yo) treated in our institution during the six week peak period of the pandemic were included. Prospective data for all paediatric trauma and urgent elective admissions and retrospective data for sarcoma admissions were collected. Telephone interviews were conducted with patients and families to assess Covid-19 related morbidity at 14-days post discharge.

Results: 100 children underwent surgery or interventional radiological procedures under GA between 20 March and 8 May 2020. There were 35 trauma cases, 20 urgent elective orthopaedic cases, 2 spinal emergency cases, 25 admissions for Interventional Radiology procedures under GA and 18 tumour cases. 78% of trauma cases were performed within 24 hours of referral. In the 97% who responded at two weeks following discharge , there were no cases of symptomatic COVID -19 in any patient or member of their households.

Conclusion: Despite the extensive restructuring of services and widespread concerns over the surgical and anaesthetic management of paediatric patients during this period, we treated 100 asymptomatic patients across different orthopaedic subspecialties without apparent COVID-19 or unexpected respiratory complications in the early post-operative period.

Implications: The data provides assurance for health care professionals and families and informs the consenting process.

There is NO Conflict of Interest: No

Disclosure: D. Eastwood; royalties from Oxford University Press. P. Calder: payment for development of educational presentations from Smith & Nephew, travel and accomodation expenses from S&N and Nuvasive. A. Gibson; expert testimony legal firms, grants AO Spine, payment for lectures from DePuy Synthes, All are unrelated to this article.

1101 - Utilising a day surgery unit to undertake same day discharge uni-compartmental knee replacements (UKR) - Is this the answer to re-starting elective knee arthroplasty in the post Covid-19 era?

M. Hampton¹, A. Legg¹, A. Anderson¹

¹Rotherham District Genreal Hospital, Trauma and Orthopaedics, Rotherham, United Kingdom

Introduction: The COVID-19 pandemic has led to all inpatient arthroplasty surgery being postponed for the foreseeable future. Same day discharge arthroplasty surgery will be essential to reduce growing waiting lists. We improved our same day discharge rate from 56% to 100% by utilising a day surgery unit, rather than planning same day discharge through an inpatient ward.
 
Materials and Methods: Prospective data was collected on all patients eligible for day surgery UKR. An initial ‘Phase 1’ pathway was developed with guidelines for patients, surgeons, anaesthetist and physiotherapists. Phase 1 was lead through the elective orthopaedic inpatient ward. 
‘Phase 2’ was developed with adjustments to the guidelines, specifically postoperative analgesics, anaesthetic techniques and a bladder management protocol. The principal difference between phases was that all patients were admitted and discharged through the day surgery unit. 
 
Results: All patients eligible for day surgery UKR were included. 
Phase 1 ran from September 2017. 29 out of 40 UKRs met the inclusion criteria. 56% (15/29) of patients were successfully discharged on the same day of surgery from the inpatient ward. Reasons for failed discharge included pain, nausea and vomiting, dizziness, wound problems and urinary retention. 
Phase 2 was implemented from April 2019. 21 out of 26 UKRs met the inclusion criteria. 100% (21/21) of patients were successfully discharged the same day, after being admitted and discharged through the day surgery unit. There were no re-admission following discharge. No patients were admitted to the inpatient ward for any period of time. 
 
Conclusion: Discharge on the day of surgery following UKR can be reliably and safely achieved by using a day surgery unit rather than an inpatient ward. This has allowed us to begin offering patients arthroplasty surgery during the COVID-19 pandemic.

There is NO Conflict of Interest: Yes

1155 - IMPACT-Scot Report on COVID-19 and Hip Fracture: A multicentre study assessing mortality, predictors of SARS-CoV-2 infection and the effects of social lockdown on epidemiology

A. Hall¹, N. Clement¹, L. Farrow², I.-S. Study Group¹, A. MacLullich³, G. Dall⁴, C. Scott⁵, P. Jenkins⁶, T. White¹, A. Duckworth¹

¹University of Edinburgh, SORT-IT / Dept of Orthopaedics & Trauma, Edinburgh, United Kingdom, ²University of Aberdeen, Aberdeen, United Kingdom, ³University of Edinburgh, Geriatric Medicine, Usher Institute, Edinburgh, United Kingdom, ⁴Borders General Hospital, Dept of Orthopaedics & Trauma, Melrose, United Kingdom, ⁵University of Edinburgh, Dept of Orthopaedics & Trauma, Edinburgh, United Kingdom, ⁶Glasgow Royal Infirmary, SORT-IT / Dept of Orthopaedics & Trauma, Glasgow, United Kingdom

The primary aim was to assess the independent influence of COVID-19 on 30-day mortality for hip fracture patients. The secondary aims were to determine whether (1) there were clinical predictors of COVID-19 status and (2) whether social lockdown influenced the incidence and epidemiology of hip fracture.

A national multicentre retrospective study was conducted of all patients presenting to six trauma centres or units with a hip fracture over a 46-day period (23 days pre- and post-lockdown). Patient demographics, residence, place of injury, presentation blood tests, Nottingham Hip Fracture Score, time to surgery, operation, ASA grade, anaesthetic, length of stay, COVID-19 status and 30-day mortality were recorded.

Of 317 patients with acute hip fracture, 27 (8.5%) had a positive COVID-19 test. Only 7 (26%) had suggestive symptoms on admission. COVID-19 positive patients had significantly lower 30-day survival compared to those without COVID-19 (67% versus 92%, p<0.001). COVID-19 was independently associated with increased 30-day mortality risk adjusting for: (1) age, sex, residence (hazard ratio (HR) 2.93, p=0.008); (2) Nottingham Hip Fracture Score (HR 3.52, p=0.001), and (3) ASA (HR 3.45, p=0.004). Presentation platelet count predicted subsequent COVID-19 status; a value of <217 x109/L was 68% specific and sensitive (95% CI 58 to 77, p=0.002). A similar number of patients presented with hip fracture in the 23 days pre-lockdown (n=160) and 23 days post-lockdown (n=157); there was no significant (all p>0.15) difference in patient demographics, place of injury, Nottingham Hip Fracture Score, time to surgery, ASA, or management.

COVID-19 was independently associated with an increased 30-day mortality rate for patients with hip fracture. Notably, most patients with hip fracture and COVID-19 lacked suggestive symptoms at presentation. Platelet count was an indicator of risk of COVID-19 infection. These findings have implications for the management of hip fracture, in particular the need for COVID-19 testing.

There is NO Conflict of Interest: Yes

1164 - Effect of COVID-19 on best practice care of hip fracture patients: An analysis from National Hip Fracture Database (NHFD)

B. Tyas¹, J. Lukic¹, M. Wilkinson², K. Singisetti¹

¹Queen Elizabeth Hospital, Gateshead Health NHS Foundation Trust, Trauma & Orthopaedics, Gateshead, United Kingdom, ²Queen Elizabeth Hospital, Gateshead Health NHS Foundation Trust, Orthogeriatric Medicine, Gateshead, United Kingdom

Background: The aim of our study was to look at the impact of COVID-19 on the best practice care of hip fracture management. This was done through the publicly available national data from NHFD.

Methods: NHFD dashboard data and charts for England, Wales and Northern Ireland were analysed for the months of March to June 2020 (lockdown period related to COVID-19) to look for national trends in change in care.

Results: Best practice dropped from 61.4% in February 2020 to 58.2% in March, 45.4% in April and 43.2% in May 2020.
Prompt surgery (within 36 hours of presentation) dropped from 72.1% in February 2020 to 70.8% in March, 69.9% in April and 66.1% in May 2020.
Orthogeriatric review dropped from 91.8% in February 2020 to 90.2% in March, 78.8% in April and 78.0% in May 2020.
Non-operative treatment of hip fractures changed from an average of 2.3% in February 2020 to 3.1% in March, 3.3% April and 2.6% in May 2020.
The proportion of total hip replacements changed from 29.4% in February 2020 to 24.2% in March, 18.3% in April and 23.3% in May 2020.

Conclusion: The majority of hip fracture patients continued to be treated with an operation. There was a significant drop in best practice nationally for hip fracture management with the lowest recorded in April and May 2020. Whilst there was a small drop in the proportion of patients getting prompt surgery during the crisis, the predominant detrimental effect to best practice appears to be the lack of timely Orthogeriatric assessment of patients during the COVID-19 pandemic.

Implications: It is important to continue a high standard of multidisciplinary care for this vulnerable group of patients by avoiding redeployment of the Orthogeriatric team during any future spikes of COVID-19.

There is NO Conflict of Interest: Yes

1178 - Restarting elective orthopaedic services during the COVID-19 pandemic: Do patients want to have surgery?

W. Wignadasan¹, J. Chang², B. Kayani¹, C. Kontoghiorghe¹, R. Plastow², A. Magan², S. Singh², F.S. Haddad¹

¹University College London Hospital, Trauma and Orthopaedics, London, United Kingdom, ²University College London Hospital, London, United Kingdom

Introduction: As the peak of the COVID-19 pandemic passes, the challenge shifts to safe resumption of routine medical services including elective orthopaedic surgery. Protocols including preoperative self-isolation, COVID-19 testing, and surgery at a non-COVID site have been developed to minimise risk of transmission. Despite this, it is likely that many patients will want to delay surgery for fear of contracting COVID-19. The aim of this study is to identify the number of patients who still want to proceed with planned elective orthopaedic surgery in this current environment.
 
Patients and methods: This is a prospective, single surgeon study of 102 patients who were on the waiting list for an elective hip or knee orthopaedic operation during the COVID-19 pandemic. Baseline characteristics including age, ASA grade, COVID-19 risk, procedure type, surgical priority, and admission type were recorded. The primary outcome was patient consent to continue with planned surgical care after resumption of elective orthopaedic services. Subgroup analysis was also performed to determine if any specific patient factors influenced the decision to proceed with surgery. 
 
Results: Overall, 58 patients (56.8%) wanted to continue with planned surgical care at the earliest possibility. Patients classified as ASA I and ASA II were more likely to agree to surgery (60.5% and 60.0%, respectively) compared to ASA III and ASA IV patients (44.4% and 0.0%, respectively) (p=0.01). In addition, patients undergoing soft tissue knee surgery were more likely to consent to surgery (90.0%) compared to patients undergoing primary hip arthroplasty (68.6%), primary knee arthroplasty (48.7%), revision hip or knee arthroplasty (0.0%), or hip and knee injections (43.8%) (p=0.03). 
 
Conclusion: Restarting elective orthopaedic services during the COVID-19 pandemic remains a significant challenge. Given the uncertain environment, it is unsurprising that only 56% of patients were prepared to continue with their planned surgical care upon resumption of elective services.

There is NO Conflict of Interest: Yes

1305 - COVID-19: The T&O Impact in a Rural District General Hospital

D. M Navaratnam¹, S. Lanckmans¹, R. Rambani¹

¹Pilgrim Hospital, Boston, United Kingdom

Background: The COVID-19 global pandemic has led to the restructuring of surgical services nationwide, in order to combat the strain the virus was predicted to place on the NHS. This study provides an insight into our experience of the orthopaedic department at a rural district general hospital during the pandemic, the changes that occurred in order to provide surgical care in the COVID-19 era.

Method: This is a case control study. All patients with neck of femur fracture admitted to the hospital at the start of the UK lockdown were included in the study. Data collection period was from 25/03/20- 17/05/20.This was retrospectively compared with 2019 data during the same time period to minimise risk of bias. Data was obtained through admission notes and national hip fracture database.

Results: A total of 50 patients pre-COVID-19 pandemic and during COVID-19 pandemic were assessed. Median age group was 82.5 and 83 respectively. There were more female admissions in both groups, 37 patients (74%) pre-COVID and 34 patients (68%) during COVID-19. Post-operative respiratory complications were similar in both groups, 3 patients(6%) vs 4 patients(8%) respectively. One patient contracted COVID-19 during their stay which only required ward based treatment. There was no inpatient mortality recorded during the COVID-19 pandemic. A positive outcome noted was length of hospital stay was shorter in the COVID-19 setting (12 days versus 8 days, respectively) and this finding was statistically significant (p<0.001).

Conclusion: Our outcomes for COVID-19 related complications were better than those reported in the literature and this could be due to the low prevalence of COVID-19 in our region. As there is regional variation in the prevalence of COVID-19 across the United Kingdom, we suggest that surgical departments could make local decisions and follow a multi-disciplinary team approach rather than following a national ‘one-size fits all’ guidelines.

There is NO Conflict of Interest: Yes

1521 - FFP3 masks usage by frontline Healthcare Professionals during COVID-19 pandemic: A snapshot survey

R.M. Raghavendra¹, V. Vardarajan², K. Mohanty³

¹University Hospital of Wales, Trauma and orthopaedics, Cardiff, United Kingdom, ²Princess of Wales Hospital, Department of Anaesthetics, Bridgend, United Kingdom, ³University Hospital of Wales, Trauma and Orthopaedics, Cardiff, United Kingdom

Purpose: Usage of protective masks such as FFP3 (Filtering Face Piece mask class 3) during the COVID-19 pandemic resulted in some healthcare professionals reporting symptoms such as skin damage and facial bruising. This snapshot survey was aimed at evaluating the extent and severity of such adverse physical effects experienced by users of FFP3 disposable masks.

Methodology: Healthcare staff working at secondary and tertiary care hospitals from two neighbouring health boards were invited to answer an online questionnaire between 25-04-2020 and 17-05-2020. Data on duration of mask usage, tolerance time, extent of pain or discomfort, general and facial symptoms experienced were collected.

Results: A total of 209 responses were collected of which 47.4% (n = 99) reported moderate-to-severe pain or discomfort after wearing FFP3 masks. Pressure marks over the face and nose (83.7%, n = 175), and 'thirst' (66.1%, n = 138) were the most common facial and general symptoms experienced respectively. The average duration of FFP3 mask usage was 2 hours or more in 83% (n = 175) but only 66.5% (n = 139) could tolerate it for 60 minutes or less. There was a statistically significant association between duration of usage and severity fo pain or discomfort experienced (Kruskal-Wallis test, p= 0.0007). Certain groups of professionals such as Doctors and Nurses working in Intensive care and theatre settings were more likely to experience severe symptoms than others (Kruskal-Wallis test, p = 0.008)

Conclusion: Adverse physical symptoms were experienced by a high proportion of health care professionals following the usage of disposable FFP3 masks. The severity worsens with increased duration of use. Certain groups of professionals were more prone to adverse symptoms.

Implications: For the safety and well-being of healthcare staff caring for patients with COVID-19, safer alternatives such as full-face-masks or powered-respirators may need to be considered.

There is NO Conflict of Interest: Yes

1529 - The timing of a COVID-19 diagnosis and its impact on 30-day mortality in neck of femur (NOF) fracture patients

J. Hadfield¹, G. Dietz-Collin¹, S. Wales¹, A. Gray¹

¹James Cook University Hospital, Trauma and Orthopaedics, Middlesbrough, United Kingdom

Background: 2020 has seen the spread of novel coronavirus (COVID-19), leading to large numbers of deaths globally. Locally, the number of orthopaedic admissions through the pandemic has decreased, but the incidence of NOF fractures has remained the same. Our aim was to compare the NOF patients who tested positive for COVID-19 pre-operatively with patients who were diagnosed post-operatively and examine how the timing of diagnosis impacted their 30-day mortality.

Methods: NOF fracture patients were identified at James Cook University Hospital using the National Hip Fracture Database (NHFD) between 01/03/20 and 31/05/20 inclusively. All patients with a NOF fracture were included and their 30-day mortality was recorded. Patients were logged as COVID-19 positive if they swabbed positive during in the 30 days from admission. Those who were COVID-19 suspects, but had a negative sample were recorded as negative.

Results: 117 NOF patients were included. 27 patients had a positive COVID-19 sample. 15 patients were recorded as COVID-19 positive pre-operatively and 12 post-operatively. 30-day mortality for patients with a NOF fracture and a positive COVID-19 sample was 29.6% compared to 6.7% in those who did not. 30-day mortality in COVID-19 positive pre-operative patients was 40%, compared to 16.7% in those found to be COVID-19 positive post-operatively.

Conclusions/findings: During the study period a large proportion of patients presenting to hospital with a NOF fracture and a negative COVID-19 sample became COVID-19 positive following surgery (10.3%). The impact on mortality when testing positive post-operatively does not appear to be as dramatic as those diagnosed with COVID-19 pre-operatively. However, this group of patients still continue to have a worse 30-day mortality than those who remained COVID-19 negative (16.7% v 6.7%).

There is NO Conflict of Interest: Yes

1543 - The Impact of COVID-19 Pandemic on proximal femoral fracture fixation and its effect on Theatre time - An unexpected long-term threat to surgical training?

Z. Ansar¹, E. Barlow¹, M.P. Larsen¹, M. Cronin¹, M. Dodd¹

¹Morriston Hospital, Trauma and Orthopaedics, Swansea, United Kingdom

Background: The novel coronavirus was declared a global pandemic on 11th March 2020 and continues to test healthcare systems worldwide. Following the emergence of COVID-19 there were modifications to theatre operating practice at Swansea Bay University Health Board to increase efficiency, reduce viral exposure and manage reduced theatre staffing. Measures included the introduction of full personal protective equipment and consultant led operating. 

Methods: Two patient cohorts that underwent hip hemiarthroplasty and Dynamic Hip Screw fixation between April and June 2019 and 2020 – during and pre-COVID-19 - were retrospectively analysed to evaluate surgical and total theatre times.

Results: The pre-COVID-19 cohort (n=83) had a mean operating time of 77.43 minutes. The COVID-19 cohort (n=97) had a mean operating time of 63.47 minutes. Both data sets were normally distributed. A T-test was performed, and a significant difference was observed between the two cohorts for both surgical and total theatre time, with p-values of <0.00001 and 0.004823 respectively.

Conclusion: Changes to operating practice due to COVID-19 have resulted in a significant decrease in operating time driven by consultant led operating. Hip fracture surgery has traditionally been the domain of the registrar, an arena where they can develop their skills, improve surgical technique and receive consultant training and feedback. Implemented changes have led to a reduction in junior surgical exposure at a detriment to training. With continuing pressures in a post-COVID, resource poor environment, such changes have not gone unnoticed by allied specialities and hospital management. Following the pandemic there is a risk of continuing this self-perpetuating cycle, driving for these efficiency savings under the guise that this is in the patient’s best interest, especially while resources remain restrictive. It is important not to lose sight of the long-term implications of these lost training opportunities and the impact on surgeons of the future.

There is NO Conflict of Interest: Yes

1639 - Short term outcomes of femoral fragility fractures during the COVID-19 pandemic managed at a tertiary elective orthopaedic centre. The blueprint for future periprosthetic fracture management

S. Khan¹, A. Palmer¹, S. Key¹, C. Jayadev¹, J. Donaldson¹, A. Hart¹, J. Miles¹, R. Carrington¹, J. Skinner¹

¹Royal National Orthopaedic Hospital, Joint Reconstruction, London, United Kingdom

Introduction: In response to the COVID-19 pandemic the Royal National Orthopaedic Hospital (RNOH), for the first time in its history, transformed itself into a regional trauma centre with a focus on fragility fractures. This study sought to identify the short term (30 day) outcomes of neck of femur and periprosthetic fractures in this at risk cohort.

Methods: All patients above 65 admitted to the RNOH during its time as a trauma centre sustaining a femoral fracture were included. COVID-19 status was assessed based on either a positive antigen test or a clinical picture consistent with indicative of COVID-19. Patient demographics, length of stay, mortality and discharge destination were recorded. Indices within the “best practice tariff” were prospectively noted to ensure compliance with national guidelines.

Results: 152 fragility femoral fractures were included. 63 cemented bipolar hemiarthroplasty, 56 DHS/IM nail, 17 THR’s, and 13 revision arthroplasty procedures were performed. One patient was unfit for surgery and died as an inpatient. 19 patients were COVID positive on admission (10 confirmed on test and 9 clinical diagnosis) and 5 become positive after surgery (2 confirmed on test and 5 clinical diagnosis). 30-day mortality rate was 9.5% (12 patients) when patients were not COVID positive at any time, and 32.0% (8 patients) for patients who were COVID positive during the perioperative period (p=0.006).

Conclusion: Patients sustaining fragility fractures of the femur who develop COVID-19 during the perioperative period have significantly increased 30 day mortality. This should be discussed with patients and their families when developing patient-specific care plans. From our experience a centralised fragility fracture service is capable of delivering high quality care, going forward this may function as a blueprint for “NOF centres”. Moreover, with the increasing burden of peri-prosthetic fractures this model represents a paradigm shift in the delivery of care.

There is NO Conflict of Interest: Yes

1676 - Validating waiting list patients using Torbay Charts Patient Decision Aid post COVID

R. Ramesh¹

¹Torbay Hospital, Department of Trauma & Orthopaedics, Torquay, United Kingdom

Background: Getting it Right First Time’s (GIRFT) Good Clinical and Operational Practice Guidance Post-COVID Transformation & Recovery programme (July 2020), makes numerous recommendations for restarting elective joint replacement surgery. This includes Shared Decision Making (SDM) to reaffirm patient choice. However, it has not identified any specific tool enabling this at the shop-floor level.
Numerous studies show Patient Decision Aids (PDA) could be the key to unbiased decision making, enhance knowledge, and decrease regret. Efficient use of PDA in orthopaedics decreased the choice of surgery by a minimum of 11.5% (Sepucha et al, 2017). Current PDAs have many shortfalls e.g. offering inappropriate choices, which is recognised by NICE review of PDA Tools (June 2020).
TC is a novel PDA with a multi-layer, multi-formatted approach addressing many of the identified limitations. The infographic overview allows appropriate treatments to be selected based on the stage of the disease, providing a focal point for SDM conversations. The web-version allows user-driven side-by-side comparisons of pros and cons, with links to a comprehensive video library.

Methods: Pilot testing over 8 weeks with 121 patients was conducted (pre-COVID) to evaluate TC in SDM using a questionnaire.

Results: 92% strongly agreed TC helped their SDM process. 91% strongly agreed they understood various treatment options. Healthcare Practitioners felt the consultation was engaging and focused. 13.2% chose non-operative treatment, with 7.4% expecting surgery but opting for conservative methods.

Conclusion: This unique approach allows for efficient remote consultations. This will help in validating waiting lists, reconfirming patient choice, and may allow some to choose non-operative alternatives if appropriate.

Implications: If choice is to be offered following the Montgomery verdict reappraisal, then it should be all-encompassing with options for surgical and conservative lines being discussed. TC’s revolutionary approach enhances SDM and can be the tool to meet GIRFT’s guidance.

There is NO Conflict of Interest: Yes

1683 - COVID19 and Its Impact on Scottish Orthopaedic Trainee

J.W. Lim¹, H. Rehman¹, D. Cairns¹

¹Aberdeen Royal Infirmary, Trauma and Orthopaedic, Aberdeen, United Kingdom

Due to the outbreak of coronavirus disease 2019 (COVID-19), majority of elective orthopaedic services have ceased and some trainees have been redeployed. The Scottish Government’s approach to COVID-19 is different to England. The immediate future of elective orthopaedic training remains unclear. We conducted a trainee survey to investigate the impact of COVID-19 on the Scottish orthopaedic trainee. An online survey was distributed to all Scottish orthopaedic trainees. All data collection was anonymous.
Across all 4 Scottish regions, 44 trainees have responded: 36% from North, 25% from East, 23% from West and 16% from South East. Trainees at all stages of training responded to the survey, with the most responses received from specialist trainees in third year of training (ST3) (21%). In response to the pandemic, 20% of trainees have been redeployed, with majority of them from North Scotland. Since the reconfiguration of service, only 25% of trainees have done >20 operations in a month. Most units (36%) have 3 to 4 trauma admissions and majority of the units (73%) only managed to complete 2 to 3 trauma cases during 8am to 5pm working day. The majority of trainees received online teaching (95%) and find them useful (96%). Outcome 10 was deemed a reasonable ARCP option during the pandemic by 70% of trainees. Majority of trainees (91%) report no difficulty engaging with supervisors in completing relevant reports for ARCP. If COVID-19 outbreak is likely going to reduce operating opportunities for a long period, only 32% of trainees would be open to the idea of making standard surgical specialty training longer whereas 52% of trainees would be open to longer working hours to achieve certification in Trauma and Orthopaedic surgery within 96 months.
The outbreak of COVID-19 has clearly affected Scottish orthopaedic training. Attempts at teaching are still being made consistently across Scotland.

There is NO Conflict of Interest: Yes

1737 - Resuming elective services in the COVID-19 era: A unique insight into patient risk aversion

S. Madanipour¹, O. Al-Obaedi¹, A. Ayub¹, F. Iranpour¹, P. Subramanian¹

¹Royal Free London NHS Foundation Trust (Barnet Hospital), Department of Trauma and Orthopaedic Surgery, London, United Kingdom

Background: There has been a wealth of guidance from the government and orthopaedic community on how best to ensure the safety of our patients and colleagues as we recommence elective surgery in the UK.  

The primary objective was to determine what proportion of patients felt they should be prioritised with proceeding with elective hip and knee arthroplasty surgery, having been counselled on the contemporary evidence available regarding the additional risks posed by COVID-19. The secondary objective was to investigate what variables affected this decision. 

Method: Patient demographics and medical history from a single-surgeon's waiting list in a district general hospital were recorded. A standardised telephone discussion was had with all the patients noting the severity of pain and the reasons for not wanting to proceed with surgery at this time. 

Statistical analysis was performed to determine what factors impacted the decision-making process. 

Results: 70.6% (96/136) patients wished to proceed with surgery as soon as possible, with a mean age of 68.5 years compared with 72.4 years for patients who did not wish to proceed (p=0.03).  The decision to proceed with surgery was not correlated with gender, ASA or COVID-19 risk. Within the matched subgroups, patients under the age of 70 years were more willing to proceed with hip arthroplasty surgery (87.9%) compared to knee arthroplasty surgery (57.1%) (p=0.007). 75% of the patients who did not wish to proceed with surgery expressed concerns about peri-operative COVID-19 infection. 

Conclusion: There is a significant proportion of arthroplasty patients on waiting lists who would be willing to accept the increased risks associated with COVID-19 to undergo surgery on an urgent basis.  

The subgroup of younger hip arthroplasty patients are more willing than knee arthroplasty patients to proceed with surgery. This study provides a reflection of patient attitudes to risk aversity when considering arthroplasty surgery.  

There is NO Conflict of Interest: Yes

1739 - Rapid Transformation of Orthopaedic Management during COVID-19: A Closed Loop Audit of the British Orthopaedic Association (BOAST) Guidelines of Outpatient Orthopaedic Fracture Management

L. Kurar¹, S. Dunkerley¹, K. Butler¹, M. James¹, I. Lowdon¹

¹Great Western Hospital, Swindon, United Kingdom

Background: COVID-19 has had profound management implications for orthopaedic management due to balancing patient outcomes with clinical safety and limited resources. The BOAST guidelines on outpatient orthopaedic fracture management took a pragmatic approach. At Great Western Hospital, Swindon, a closed loop audit was performed looking at a selection of these guidelines, to assess if our initial changes were sufficient and what could be improved.
 
Methods: An audit was designed around fracture immobilisation, type of initial fracture clinic assessment, default virtual follow up clinic and late imaging. Interventions were implemented and re-audited.
 
Results: Initially 223 patients were identified over 4 weeks. Of these, 100% had removable casts and 99% did not have late imaging. 96% of patients were initially assessed virtually or had initial orthopaedic approval to be seen in face to face clinic. 97% had virtual follow up or had documented reasons why not. The 26 patients who were initially seen face to face were put through a simulated virtual fracture clinic. 22 appointments and 13 Xray attendances could have been avoided. We implemented a change of requiring all patients to be assessed at consultant level before having a face to face appointment. The re-audit showed over 99% achievement in all areas. 
 
Conclusion: Virtual fracture clinics, both triaging new patients and follow-up clinics have dramatically changed our outpatient management, helping the most appropriate patients to be seen face to face. Despite their limitations, they have been well tolerated by patients and improved patient safety and treatment.

There is NO Conflict of Interest: Yes

1747 - COVID-19 and the Irish National Spinal Injuries Unit: Impact on service provision and strategies to protect urgent care

F. Power¹, A. Juhdi¹, M. Macken¹, K.A. Synnott¹, J.S. Butler¹

¹Mater Misericordiae University Hospital, National Spinal Injuries Unit, Dublin, Ireland

Background: The COVID-19 pandemic has had a dramatic impact on the provision of healthcare worldwide. The delivery of a national spinal service for emergent surgery, elective surgery and outpatient assessment has been incredibly challenging. Both the volume and aetiology of spinal cases is markedly different to those seen in previous years.
 
Methods: Prospectively collected data regarding referrals to, and operative workload of, the Irish National Spinal Injuries Unit (NSIU) during the period of national lockdown in response to the COVID-19 pandemic was compared to the same period in 2019. Strategies employed to protect the capacity to deliver urgent spinal care are outlined.
 
Results: During the period of national lockdown there was a 47% decrease in the number of urgent referrals to the NSIU and a 61% reduction in the number of surgical cases performed. A particularly concerning finding was that for surgical cases there was a 400% increase in attempted suicide as the cause of injury with this cohort representing 11% of all surgical cases performed during the pandemic lockdown. The introduction of a national instant messaging application (Siilo) referral group resulted in a median time to first response by a National Spinal Injuries Unit (NSIU) surgeon of 15.5 minutes.
 
Conclusions: The COVID-19 pandemic has had a significant impact on the provision of a national spinal service, however innovative strategies have been adopted to protect the capacity to provide urgent care. The impact of the lockdown on mental health is reflected in the increased number of operative cases secondary to attempted suicide.

There is NO Conflict of Interest: Yes

1811 - The Outcomes of Orthopaedic Trauma During the COVID-19 Pandemic

A. Chowdhury¹, R. Collins¹, D. Marsland¹

¹Hampshire Hospitals Foundation Trust, Basingstoke, United Kingdom

Background: During the Coronavirus (COVID-19) outbreak of 2020, the provision of operative treatment for orthopaedic trauma has continued. Uncertainty exists, including the risk of contracting COVID-19 during an orthopaedic surgical admission and the risk of mortality. An initial study from Wuhan reported a mortality rate of 20.5% for patients with coronavirus undergoing elective surgery.
The aim of this study was to evaluate the outcomes of patients undergoing orthopaedic trauma surgery during the COVID-19 pandemic, including mortality and in-hospital virus contraction.

Methods: A database was populated prospectively, from the 1st May 2020, of all patients undergoing trauma surgery at Basingstoke and North Hampshire Hospital. Data collected included demographic information, COVID-19 swab results, mortality, and length of stay. Furthermore, a telephone COVID-19 symptom screening questionnaire was conducted at seven days following hospital discharge.

Results: Between the 1st of May and the 30th June 2020, 324 patients underwent orthopaedic trauma surgery. Eight (2.5%) had a positive COVID-19 swab on admission; 312 (96.3%) had a negative swab and four (1.2%) did not have a swab. Of the patients who tested positive on admission, two (25.0%) were symptomatic, of whom one died (12.5% mortality). There were 6 (1.9%) mortalities in total. Two patients (0.64%) converted from a negative admission swab to a positive subsequent swab, both of whom remained asymptomatic. There were 206 post-discharge telephone responses, of which all were negative.

Conclusion: There is a high risk of mortality for hip fracture patients with symptomatic COVID-19 undergoing trauma surgery. However, the local prevalence of COVID-19 is low and the risk of contraction during surgical admission for trauma surgery is low.

Implications: The findings from trauma surgery are reassuring and indicate that, with careful screening and pre-operative isolation, elective orthopaedic surgery may be safe to resume in areas of low COVID-19 prevalence.

There is NO Conflict of Interest: Yes

1845 - Safely Performing Urgent Revision Arthroplasty During Pandemic of COVID-19

A. Elsiofy¹, S. Perkins¹, A. Ringrose¹, J. Stammers¹, S. Alazzawi¹, P. Mitchell¹

¹St Georges University Hospital, Trauma & Orthopaedics, London, United Kingdom

Background: The COVID-19 pandemic has severely affected health care systems. Non-life or limb threatening operations were put on hold. Parallel to that, many patients who were waiting urgent operations experienced an increased degree of symptoms and presented acutely to the emergency department. We present the outcome of performing urgent revision arthroplasty surgery during the COVID-19 pandemic in a major teaching hospital.  

Methods: Our hospital is a tertiary referral centre for arthroplasty, major trauma and has the largest intensive care capacity in the region. We continued to receive urgent arthroplasty emergencies either through our emergency department or transferred from regional hospitals. The hospital infrastructure adapted to have red, amber and green pathways with matched wards, theatres and ICU. Patients underwent risk stratification and screening of COVID-19 status. Between March and June 2020, we performed 13 urgent revision knee or hip arthroplasties. The medical notes were reviewed, and postoperative complications were recorded. All patients underwent discussion through a virtual arthroplasty MDT meeting. 

Results: 13 revisions were performed (6 male, 7 female). Average age was 69.6 years (36 – 86). All patients were ASA 3 or 4. The indication for surgery was infection (10) patients, periprosthetic fracture (1) and periprosthetic fracture of chronically infected joints (2). Five patients required endoprosthetic replacement. Three patients underwent debridement and implants retention (DAIR). 85% were managed perioperatively in the ICU. We have no mortality in short term and none of the patients were tested positive or become symptomatic from covid-19 infection. 

Discussion: The systems setup ensured complex revision arthroplasty patients were successfully managed despite the pandemic of COVID-19. If second wave of COVID occurs, the pathways can be rapidly initiated to minimise the impact on emergency arthroplasty cases. The role of arthroplasty MDT, pragmatic pathway and risk stratification of patients can ensure safe care for these patients. 

1856 - Drill Splatter in Orthopaedics Procedures and Its Importance During the COVID-19 Pandemic: An Experimental Study

R. Kabariti¹, N. Green¹, R. Turner¹

¹Princess Royal Hospital, Shrewsbury & Telford NHS Trust, Trauma & Orthopaedics, Telford, United Kingdom

Background: During the COVID-19 pandemic, drilling has been classified as an aerosol generating procedure. However, there is limited evidence in the literature to quantify the effects of bone drilling on splatter generation and its subsequent risk to the operating surgeons’ safety.

Objective: To quantify the effect of drilling on splatter generation within the orthopaedic operative setting.

Methods: This study was performed using a Stryker System 7 dual rotating drill at full speed. Fluorescein was used as a fluid medium to simulate drill splatter conditions, with similar viscosity to blood. A UV light was used to detect macroscopic droplets arising from the drill splatter. A surgical microscope with x10 magnification was used to detect microscopic droplets. The investigators drilled directly into a saw bone (0cm). Freehand use of the drill at 20cm, 50cm and 100cm above the saw bone was also undertaken to simulate the surgeon “testing the drill battery” (working arm’s length). The furthest droplets were then marked and the distance between the droplet displacement and the drill was measured in centimetres (cm). This was repeated using a drill guide/sleeve.

Results: Drilling directly into bone produced drill splatter with a 7cm droplet displacement away from the target. Operating the drill at 100cm height above the target produced the greatest splatter generation with a 95cm droplet displacement. Microscopic fluorescein droplet generation was not noticed at farther distances than what can be macroscopically seen. Using the drill guide, there was negligible drill splatter generation.

Conclusion: Our study has shown lower than anticipated drill splatter generation. The use of a drill guide/sleeve protects against splatter. We recommend using a drill guide at all times and avoiding free hand drilling to reduce the effect of viral transmission in the operative setting.

There is NO Conflict of Interest: Yes

253 - A non-inferiority RCT comparing the effectiveness and safety of aspirin vs rivaroxaban in post-operative thromboprophylaxis in primary hip arthroplasty with the Intention-to-treat

M Tahir¹, AR Jamali¹, G Mahboob¹, FuK Zimri², S Khan³

¹Jinnah Postgraduate Medical Centre, Orthopaedics, Karachi, Pakistan, ²National Institute Rehabilitation of Medicine, Orthopaedics, Islamabad, Pakistan, ³Whiston Hospital NHS Trust, Orthopaedics, Prescott, United Kingdom

Introduction: To evaluate the effectiveness and safety of Aspirin with Rivaroxaban in preventing symptomatic Deep Venous Thrombosis and Pulmonary Embolism after primary and revision hip replacements.

Methods: A randomized controlled trial on 3208 patients who underwent primary and revision hip replacement for various causes were randomized by a computer-generated algorithm stratified by age, sex and type of arthroplasty. The group which was allocated to treatment with rivaroxaban received -10 mg of Rivaroxaban daily for 30 days of treatment and the other group received 81 mg dose aspirin for 30 days.

Results: The incidence of Deep Venous Thrombosis and Pulmonary Embolism at 30 days in primary hip replacement patients was 1.15% and 0.90%, and 1.32% and 0.30% and in Rivaroxaban and Aspirin group respectively.
Summing the results of primary and revision hip replacement patients, there was no significant difference in 30-day, 90-day, and 1-year Deep Venous Thrombosis and 30 and 90 day bleeding episodes between Aspirin and Rivaroxaban group under 0.05 significant level.
Compared with Rivaroxaban users, patients treated with Aspirin in primary surgery had a lower probability of developing Pulmonary Embolism at 30 days, at 90 days, and at 1-year follow-up (ORs, 0.18 (0.04 – 0.82), 0.21 (0.06 – 0.75), and 0.21 (0.06 – 0.75), respectively).
Similarly, patients treated with Aspirin had a lower probability of developing wound hematoma under 30 days and mortality within 30 days and under one year (ORs, 0.38 (0.18 – 0.78), 0.07 (0.01 – 0.55), and 0.53 (0.32 – 0.87), respectively) in comparison to Rivaroxaban.

Conclusions: Aspirin may be an effective and safe option for Venous thromboembolism prophylaxis in patients receiving primary hip replacements and can be considered as an alternative to Rivaroxaban.

There is NO Conflict of Interest: Yes

297 - The National Hip Fracture Database is only as good as the data we feed it - significant inaccuracy demonstrated and how to improve it

L Maling¹, C Gray-Stephens², K Malik-Tabassum³, O Weiner², M Marples², G Faria¹, R Middleton²

¹East Kent Hospitals University Foundation NHS Trust, Margate, United Kingdom, ²Royal Cornwall Hospitals NHS Trust, Truro, United Kingdom, ³East Sussex Healthcare NHS Trust, Hastings, United Kingdom

Purpose: The National Hip Fracture Database of England, Wales and Northern Ireland (NHFD) is the largest such database in the world. Data errors in within the NHFD lead to spurious evidence which ultimately informs Orthopaedic, Anaesthetic and Orthogeriatric clinical practice.

Methods: This multi-centre quality improvement study investigated, and sought to improve data inaccuracy within the NHFD. Hip arthroplasty episodes recorded between 2011-2020 were analysed for errors in operation, implant type and cementation.

Results: Inaccuracies were observed in 20.5% of 3972 data entries. Following the introduction of a hip fracture clinical data administrator in each centre, inaccuracies reduced four-fold (5.2% of 559 data entries).

Conclusions: We advise caution when utilising NHFD data for research and audit purposes. In order to build a robust, accurate database for future research, we recommend the incorporation of specialist data administrators into the hip fracture multidisciplinary team.

There is NO Conflict of Interest: No

378 - Incidence of peri-prosthetic fracture with the cemented collarless polished taper stem: the Nottingham experience

M Higgins¹, S Hudson¹, R Gnap¹, J Harvey¹, A Manktelow¹

¹Nottingham University Hospitals HS Trust, Orthopaedics, Nottingham, United Kingdom

Introduction: Peri-prosthetic fractures (PPF) are a serious complication of total hip replacement (THR). Recent publications have suggested a higher prevalence of PPF with the CPT® stem compared to other polished taper stem designs and a higher revision rate for PPF in the UK National Joint Registry (NJR). The incidence of PPF was assessed in a consecutive series of patients undergoing elective THR in an NHS teaching hospital.

Methods and materials: NJR records were obtained for consecutive patients receiving a CPT® stem since its introduction with a minimum 4 year follow up. Data were cross-checked against a prospective local trauma database. All available imaging carried out after primary surgery was reviewed on a regional digital x-ray platform and details of any fractures recorded. Canal morphology was assessed using cortical thickness index (CTI)and Dorr classification and technical performance was calculated by measuring stem alignment and barrack cement grade.

Results: 550 stems were reviewed in 505 patients with a mean age 66 years (SD 14), 14% 80+ years and 69% females. 91% of femurs were Dorr B and the mean CTI was 0.55 (SD 0.08). There were no revisions for fracture at a mean of 71 months (range 50 – 127). We observed 2 PPF at intervals of 22 and 25 months, treated with open reduction internal fixation. The incidence of PPF was 0.36%.

Discussion: Results of this series demonstrate no evidence of an increased incidence of revision for PPF when using the CPT® stem. Registry data has the potential to underestimate PPF incidence in fractures that do not lead to revision.

Conclusions: The incidence of fracture compares favourably with published results of other cemented polished taper stems and there was 100% survivorship of stems at a mean of 6 years follow-up when taking revision for PPF as the end-point.

There is NO Conflict of Interest: Yes

512 - Evidence-based follow-up recommendations following Primary Hip and Knee replacement (UK SAFE)

M Stone^1,2,3, L Smith⁴, S Kingsbury^5,2,3, C Czoski-Murray,⁶, A Judge^7,8, R Pinedo-Villanueva⁹, R West⁶, J Wright⁶, C Smith⁶, N Arden⁹, P Conaghan^5,3,10

¹Chapel Allerton Hospital, Leeds,, Orthopaedic Surgery, Leeds, United Kingdom, ²LMBRC, Leeds, United Kingdom, ³NIHR, Leeds, United Kingdom, ⁴Weston Area Health Authority, Weston-Suoer-Mare / Bristol, United Kingdom, ⁵LIRMM, Leeds, United Kingdom, ⁶Leeds Institute of Health Sciences, Leeds, United Kingdom, ⁷Bristol University, MSK Research Unit, Bristol, United Kingdom, ⁸Medical Research Council, Southampton, United Kingdom, ⁹Nuffield Orthopaedic and Rheumatological Sciences, Oxford, United Kingdom, ¹⁰Biomedical Research Centre, Leeds, United Kingdom

Background: Follow-up of arthroplasty varies widely across the UK. The aim of this NIHR-funded study was to employ a mixed-methods approach to examine the requirements for arthroplasty follow-up and produce evidence-based and consensus-based recommendations. It has been supported by BHS, BASK, BOA, ODEP and NJR.
 
Methods: Four interconnected work packages were undertaken: (1) a systematic literature review; (2a) analysis of routinely-collected National Health Service data from four national datasets to understand when and which patients present for revision surgery; (2b) prospective data regarding how patients currently present for revision surgery; (3) economic modelling to simulate long-term costs and quality-adjusted life years associated with different follow-up care models and (4) a Delphi- consensus process, involving all stakeholders, to develop a policy document to guide appropriate follow-up care after primary hip and knee arthroplasty.
 
Results: The following Recommendations were agreed:

• For ODEP10A* minimum implants, it is safe to disinvest in routine follow-up from 1 to 10 years post non-complex hip and knee replacement provided there is rapid access to orthopaedic review 
• For ODEP10A* minimum implants in complex cases, or non-ODEP10A* minimum implants, periodic follow-up post hip and knee replacement may be required from 1 to 10 years
• At 10 years post hip and knee replacement, we recommend clinical, which may be virtual, and radiographic evaluation. 
• After 10 years post hip and knee replacement, frequency of further follow-up should be based on the 10 year assessment; ongoing rapid access to orthopaedic review is still required.

Conclusions and Implications: These recommendations apply to post primary hip and knee replacement follow-up.
The 10-year time point in these recommendations is based on a lack of robust evidence beyond ten years. The term complex cases refer to individual patient and surgical factors that may increase the risk for replacement failure.
 
Disclosures: Funded by NIHR HS&DR.

There is NO Conflict of Interest: Yes

771 - ABDUCTOR TENDON RECONSTRUCTION WITH LARS (LIGAMENT AUGMENTATION AND RECONSTRUCTION SYSTEM) FOR ABDUCTOR FAILURE AFTER TOTAL HIP REPLACEMENT

K.K. Dash¹, A. Saad¹, I. Wilson¹, I. Malek¹

¹Wrexham Maelor Hospital, Trauma and Orthopaedics, Wrexham, United Kingdom

Background: Hip abductor tendon (HAT) failure following anterolateral total hip replacements (THR) is uncommon but extremely difficult to treat, with no reliable procedures. Results of HAT reconstruction augmented by Ligament Augmentation and Reconstruction System (LARS) in native hips is encouraging. However, evidence is scarce for LARS as a salvage procedure for HAT failure following THR. We report early results of utilisation of this technique.

Methods: Multi-surgeon, single-centre, consecutive series of all HAT tear reconstructions with LARS augmentation in the period from Sep-2018 to Nov-2019. Ten reconstructions performed in 9 patients (one bilateral) (7 females, 2 males) (average age 73.4 years). Surgical technique involved mobilisation of abductors from pelvis, reattachment using suture anchors, augmented with LARS. Clinical outcomes were assessed in Feb-2020 (mean follow-up duration – 364 days) independently by a doctor not previously involved in care.

Results: Mean time-gap between THR and LARS procedure was 23 months (range 11 – 35). Oxford Hip Score improved from prior surgery (mean 17, median 11.5) to post-surgery (mean 29.1, median 33) (statistically significant, Wilcoxon-signed-rank-test). Lateral hip pain improved from an average of 6/10 on visual analogue scale pre-surgery to 2/10 after surgery. Antigravity abductor power (MRC grade 3 or more) was achieved in 6 out of 10 cases after surgery. Trendelenburg test remained positive in 6 cases; however mobility (walking distance and need for assistive devices) improved in 6 out of 10 cases. In 8 out of 10 cases, patients were either ‘satisfied’ or ‘very satisfied’ with the outcome.

Conclusion: Allowing for limitations of this study (small sample size, no control arm), LARS augmented hip abductor reconstruction appears to improve pain, function and patient satisfaction in most patients presenting with hip abductor tears following THR. Authors believe patients should be involved pragmatic discussion that some amount of weakness in abductors and gait issues may persist.

There is NO Conflict of Interest: Yes

1006 - THE INFLUENCE OF HOSPITAL LEVEL VARIABLES ON HIP FRACTURE OUTCOMES

L. Farrow^1,2, A. Hall³, A. Ablett⁴, L. Aucott⁵, P. Myint⁴

¹University of Aberdeen, Aberdeen Centre for Health Data Science, Aberdeen, United Kingdom, ²Aberdeen Royal Infirmary, Trauma & Orthopaedics, Aberdeen, United Kingdom, ³Royal Infirmary Edinburgh, Trauma & Orthopaedics, Edinburgh, United Kingdom, ⁴University of Aberdeen, School of medicine medical sciences and nutrition, Aberdeen, United Kingdom, ⁵University of Aberdeen, Health Services Research Unit, Aberdeen, United Kingdom

Introduction: Despite widespread acknowledgement that the determinants of hip fracture outcomes are complex and multifactorial, there is surprisingly little evidence regarding the influence of hospital level service characteristics on hip fracture care. 

Methods: We set out to address this knowledge gap through a retrospective cohort study utilising publically available national audit registry data from the National Hip Fracture Database (NHFD). Analysis included details of hospital level variables and outcomes for 176 participating hospitals treating over 66,000 hip fracture patients.

Results: The primary outcome was 30 day mortality. Univariable outcome analysis for hospital level service provision factors revealed that the only predictor of 30 mortality was hip fracture trial involvement (no trial involvement: median 6.3, trial involvement:  median 5.7; W = 4009.5; p-value = 0.0392). The number of cases per year, hospital type, MTC status, orthogeriatric care model, bed number, ward HDU area, theatre sessions per week, and presence of dedicated hip fracture sessions (HFS) were not significantly associated with 30 day mortality. 
Presence of HFS was however associated with a higher proportion of patients achieving prompt surgery. Shorter acute length of stay, shorter overall stay, and the percentage of patients achieving the best practice tariff were all positively associated with a greater number of hip fracture cases per year. 

Conclusions: Hospital participation in clinical trials is associated with an improvement in hip fracture mortality. This is likely related to a concomitant drive within these centres to produce high-level research and quality improvement. The association of greater hospital hip fracture caseload and dedicated theatre sessions with process of care outcome improvement provides evidence for centralisation of hip fracture services to increase care efficiency.

Implications: This evidence provides vital knowledge of important benchmarking factors when considering hip fracture service configuration.

There is NO Conflict of Interest: Yes

1659 - Total Hip Replacement versus Hemiarthroplasty for Hip Fractures: A Systematic Review and Meta-analysis of Randomised Controlled Trials

C. Wek¹, R. Foley¹, I. Reichert¹, R. Ahluwalia¹

¹King's College Hospital, Trauma & Orthopaedics, London, United Kingdom

Background: NICE guidance recommends that patients with displaced intracapsular hip fractures should be offered THR if they were independently mobile, not cognitively impaired and medically fit for surgery. However, despite this guidance, just 33% of patients eligible for a THR receive this. Evidence for these guidelines is largely based on a 2010 Cochrane review by Parker et al. However, emerging evidence from recent randomised controlled trials (RCTs) suggest no difference in outcomes between THR or HA. We performed a systematic review and meta-analysis of RCTs to evaluate if there truly was no difference between these interventions.

Methods: A systematic review and meta-analysis of RCTs was performed and reported in accordance with the PRISMA statement. We analysed functional outcome scores; re-operation rates; complications and mortality. Meta-analysis was performed using a random effects model to derive estimated relative risk (RR) ratios as per DerSimonian & Laird’s method.

Results: 13 RCTs met the eligibility criteria and the overall pooled sample size was 3,050. Of these, 1,386 patients received THR and 1,425 received HA. There was no significant difference in Harris Hip Scores (HHS), re-operation rate (I² = 12.6%, p=0.25) and mortality between groups (I² = 0.0%, p=0.08). Dislocation rates were higher in the THR group. A subgroup analysis was performed comparing outcomes in patients <80 to those >80. There was a 20-25% increase in the RR of dislocation in patients >80 in the THR group.

Conclusion: In contrast to previous studies, there is no difference between re-operation and mortality between THR and HA. There is a statistically significant but clinically unimportant difference in functional outcomes between the two interventions. We found a significantly higher risk of dislocation in patients undergoing THR, particularly in those >80. Hemiarthroplasty implant choices have a bearing on clinical outcome and should be recorded in the NJR.

There is NO Conflict of Interest: Yes

1731 - 2 year follow up of 111 un-displaced intracapsular neck of femur fractures, treated with internal fixation, in patients over 65 years old, in the Northern General Hospital (NGH) Sheffield

S. Salih¹, E. Mills²

¹Northern General Hospital Sheffield, Trauma and Orthopaedics, Sheffield, United Kingdom, ²Northern General Hospital Sheffield, Sheffield, United Kingdom

Introduction: In undisplaced and valgus impacted intracapsular NOF fractures fixation in situ is generally accepted.
However post-operative avascular necrosis (AVN), non-union, or soft tissue irritation may require further surgery. The alternative is arthroplasty which has been shown to have higher surgical morbidity and slower mobilisation and longer length of admission. This project examines how many patients treated with fixation required further surgery.

Methods: A patient list was gathered from the National Hip Fracture Database (NHFD) for all intracapsular fractures treated with internal fixation for a 2 year period between 01/01/2015 to 31/12/2016. XRAYs, clinic and operation notes were trawled to find patients that had further surgery. Mean follow up was 742 days. National comparison data over the same period was collected from the NHFD.

Results: Of the 111 patients identified 13 went on to have a further procedure which gives a reoperation rate of 11.7%. Of the 13 patients requiring re-operation 5 patients had failure of fixation (treated with hemiarthroplasty or THR), 2 had a screw into hip joint (treated with change or removal of screw), 3 developed AVN (treated with THR), 2 had soft tissue irritation (treated with removal of screws), and 1 suffered subtrochanteric fracture (treated with IM nail).
There was no statistical difference in age or ASA grade between reoperation and no-reoperation group. For all intracapsular fractures NGH fixes 16.7% with cannulated screws (national average 4.9%) and 2.8% with sliding hip screw (national average 7.7%)

Conclusion: NGH performs over 3 times the national average cannulated screw fixation with a reoperation rate of 11.7%. Careful surgical technique, and further work to predict which patients are at higher risk of further surgery, could reduce the re-operation rate. A randomised control trial is needed to decide whether fixation or arthroplasty is the best treatment.

There is NO Conflict of Interest: Yes

1775 - Minimum Ten Year Follow up of a Randomised Trial Comparing Acetabular Component Fixation of Two Porous Ingrowth Surfaces Using Radiosteriometric Analysis

L. Rahman^1,2, M. Ibrahim², M. Teeter², D. Naudie², R. McCalden²

¹Chelsea and Westminster Hospital NHS Trust, Orthopaedics, London, United Kingdom, ²London Health Sciences Centre, London, Canada

Aim: To compare the in-vivo long-term fixation achieved by two acetabular components with different porous ingrowth surfaces using Radiostereometric Analysis (RSA).  

Patients and methods: This was a minimum ten-year follow-up of a prospective randomised trial of 62 hips with two different porous ingrowth acetabular components. RSA exams had previously been acquired through two years of follow-up. Patients returned for RSA examination at a minimum of ten years. In addition, radiological appearance of these acetabular components was analysed, and patient reported outcome measures (PROMS) obtained.

Results: Fifteen hips were available at ten years. There was no statistically significant difference in PROMS between the two groups; PROMS were improved at 10 years compared to preoperative scores. Conventional radiographic assessment revealed well-fixed cups. There was minimal movement for both porous surfaces in translation (X, Y, Z, 3D translation in mm (Median+IQR), (StikTite 0.03 (1.08), 0.12 (0.7), 0.003 (2.3), 0.37 (0.30) and Roughcoat -0.6 (0.59), -0.1 (0.49), 0.1 (1.12), 0.48 (0.38)), and rotation (X, Y, Z rotation in degrees (Median+IQR),  (Stiktite -0.4 (3), 0.28 (2), -0.2 (1) and Roughcoat - 0.4 (1), -0.1 (1), 0.2 (2)). There was no statistically significant difference between the two cohorts (p value for X, Y, Z, 3D translation - 0.54, 0.46, 0.87, 0.55 and for X, Y, Z rotation - 0.41, 0.23, 0.23 respectively) at 10 years. There was significant correlation between 2 years and 10 years 3D translation for all components (r=0.81(p=<0.001)). 

Conclusion: Both porous ingrowth surfaces demonstrated excellent fixation on plain radiographs and with RSA at ten years. Short-term RSA data are good predictors for long-term migration data. Take Home Message:

• This study reinforces the predictive power of early RSA data for long term migration.
• Both porous ingrowth surfaces demonstrated excellent fixation on plain radiographs and with RSA at ten years follow-up.

There is NO Conflict of Interest: Yes

1881 - Prospective study comparing Acetabular Bone Resection in Hip Resurfacing and Total Hip Arthroplasty

S. O'Sullivan¹, T. O'Sullivan², P. Carton², D. Filan²

¹University Hospital Waterford, Trauma and Orthopaedics, Waterford, Ireland, ²UPMC Whitfield Hospital, Department of Orthopaedics, Waterford, Ireland

Background: Acetabular bone loss is a major concern in hip resurfacing arthroplasty (HRA) as treatment of acetabular bone deficiency during revision arthroplasty is demanding and associated with worse outcomes. Despite this, there have been conflicting results from studies regarding amount of acetabular bone removed when comparing HRA and total hip arthroplasty (THA). Aim is to determine whether HRA or THA is more invasive on acetabular bone.

Methods: We prospectively evaluated the femoral neck size of 509 consecutive hips at the time of primary THA between 2014 to 2018 in an identical manner to when carrying out a HRA. From the femoral neck measurement, we determined the minimum cup size that would be used if the same hip was undergoing a resurfacing and compared it to the actual cup size implanted.

Results: Overall, we found a significantly larger acetabular cup would have been implanted if the patient underwent a HRA rather than a THA with an overall cup size difference of 4.89 mm (56.62 ± 4.7 mm versus 51.73 ± 4.2 mm; p <0.001). 89.98% (n=458) of patients would have had a larger HRA cup size. We also found that the biggest difference in cup size was in those patients with larger femoral necks.

Conclusion/ findings: This study shows that HRA removes more bone from the acetabulum than THA for the same patient. As revision surgery becomes more prevalent with an aging population and particularly as the optimal resurfacing patient has been shown to be young, active, predominantly male patients who will likely require revision, this loss of acetabular bone stock becomes hugely significant and compromises future revision surgery.

Implications: HRA in young patients will lead to revision and re-revision difficulties due to deficient acetabular bone stock.

There is NO Conflict of Interest: Yes

1926 - Improved pelvic loading of a monoblock polyethylene acetabular component

O. Farhan-Alanie¹, P. Young², D. Teixeira¹, R. Silverwood¹, A. Mohammed¹, K. Periasamy³, A. Nicol¹, R.M.D. Meek¹

¹Queen Elizabeth University Hospital, Glasgow, United Kingdom, ²Ayr Hospital, Ayr, United Kingdom, ³Hairmyres Hospital, East Kilbride, United Kingdom

Introduction: Uncemented metal acetabular components show good osseointegration, but are limited by peripheral loading leading to retroacetabular osteolysis. Cemented monoblock polyethylene components load the pelvis more physiologically, however the cement bone interface often suffers fibrous encapsulation and loosening. An uncemented titanium sintered monoblock polyethylene component may offer the optimum combination of osseointegration and anatomical loading. We aim to establish whether this monoblock polyethylene uncemented cup loads the pelvis physiologically by comparison with cemented monoblock polyethylene and trabecular metal cup.

Methods: 38 patients were prospectively enrolled and received an uncemented monoblock polyethylene acetabular component. Periprosthetic bone density (BMD) was measured using dual-energy x-ray absorptiometry over 2 years, as well as radiographic and clinical analysis. This was compared with randomised control cohorts of cemented monoblock and trabecular metal acetabular implants.

Results: In the inferior acetabulum, a significant fall (p<0.01) in BMD was seen at 6 weeks, continuing to 2 years post-operatively. In the pubis and ischium a significant (p<0.01) fall was seen at 6 weeks, which recovered towards baseline by 2 years. This is similar to the trabecular group initially, however the trabecular cup showed no recovery over time in the ischiopubic regions. The cemented cup showed no fall in BMD in inferior acetabulum, but similar initial fall in ischiopubic region with no recovery over time. This would suggest that inferior and medial to the centre of rotation the pressfit cup initially behaves similarly to the trabecular cup. However, the pressfit cup loads the pelvis differently over time, with some improvement in bone density medially.

Conclusion: The uncemented monoblock cup initially behaves similarly to the rigid trabecular metal cup with lateral rim loading, however over time this changes to more closely resemble that of a cemented polyethylene cup with increasing medial pelvic loading. We believe this may give optimised fixation and preservation of retroacetabular bone stock.

There is NO Conflict of Interest: Yes

15 - Incidence of venous thromboembolism in elective hip arthroplasty surgery: a review of 8,891 patients receiving post-operative Aspirin VTE prophylaxis

C Hutton¹, N Patel¹, S Whitehouse¹, M Wilson¹, M Hubble¹, A-A Kassam¹

¹Royal Devon & Exeter NHS Foundation Trust, Princess Elizabeth Orthopaedic Department, Exeter, United Kingdom

Background: Venous thromboembolism (VTE) is a preventable cause of morbidity and mortality in patients undergoing elective hip arthroplasty surgery. The balance of post-operative VTE prophylaxis and risk of post-operative haemorrhage remains at the forefront of surgeons mind. The National Institute for Health and Care Excellence (NICE) published updated guidelines in 2018 which recommend the use of both mechanical and pharmacological methods in patients undergoing elective hip arthroplasty surgery.

Objectives: The aim of this study was to present the venous VTE incidence in 8,891 patients who underwent total hip arthroplasty (THA) between January 1997 and March 2018 with aspirin as the primary agent for pharmacological thromboprophylaxis.

Methods: We performed an analysis of prospectively collected data of the incidence of deep vein thrombosis (DVT) and pulmonary embolism (PE) occurring with 6 months of the index operation. We also investigated the 90-day mortality of this cohort of patients.

Results: 8,891 patients were reviewed. This included 6,973 primary, 224 complex primary and 1694 revision cases. The incidence of DVT was 0.64% after elective hip arthroplasty, the incidence of PE was 0.54%. There was no difference in the incidence between primary and revision cases. The 90-day mortality was 0.88%. Cardiovascular and respiratory disease were the main causes of death following surgery. Only 0.03% of deaths (n= 3) within 90 days of index surgery were due to VTE.

Conclusion: Our results support the use of aspirin as an effective and safe form of prophylaxis against VTE following THA in accordance to NICE and recommendation. It is not associated with an increased incidence in symptomatic DVT, PE or death compared to other published studies. The fact that it is inexpensive, readily available, requires no monitoring and does not pose a risk of bleeding are other advantages.

There is NO Conflict of Interest: No

108 - ERAS PROTOCOL SUBSTANTIALLY REDUCED RE-ADMISSION AFTER TOTAL HIP ARTHROPLASTY(THA): CONSECUTIVE 1855 PATIENTS SERIES

V. Garg¹, I. Malek¹

¹Wrexham Maelor Hospital, Wrexham, United Kingdom

Introduction: Unplanned re-admissions following Total Hip Arthroplasty (THA) are undesirable as it poses inconvenience to patients as well as increases the burden on health-care institutions. The reported re-admission rates are as high as 11% following Enhanced Recovery After Surgery (ERAS) protocol after THA. The aim of this study was to assess the influence of ERAS on 28 days re-admission rates following THA in our unit.

Material and Methods: Consecutive series of 28 days readmission data following THA performed between 2011 and 2018. All primary procedures except for trauma were included in this series. Revision THA procedures were excluded. All in-patient, hospital re-admissions for any cause within 28 days following the index procedures were analysed. The medical records were used to identify the reason of re-admission and investigations were reviewed to confirm the diagnosis.

Results: There were 53 (2.85%) readmissions within 28 days of discharge after 1855 index procedures over 8 years period. Out of these, 28 (1.51%) re-admissions were due to underlying orthopaedic causes, whereas 24 (1.35%) were non-orthopaedic reasons (including medical and general surgical). Leg swelling with suspicion of DVT (n=9) and dislocation (n=9) were the two most common orthopaedic reasons for readmission, making up 64.28% of total orthopaedic re-admissions.
Yearly assessment confirms steady decline in readmissions which is currently 1.99% compared to 5.20% at the start of the ERAS process in our institution.
Our results suggest that, a matured ERAS protocol does substantially reduces 28 days re-admission for any reasons after index THA procedures. Most common reasons were leg swelling and dislocation of hip but with introduction of new implant ,effective rehabilitation and patient education during in-patient stay and easy access to arthroplasty team for further assessment in timely manner will avoid re-admission to the hospital.

There is NO Conflict of Interest: No

167 - Arthroplasty in the developing world: Our experience of 256 hip replacements at The Children's Surgical Centre Phnom Penh

J Shelton¹, S Dorman¹, H Oy¹, K Long¹, O Ngiep¹, N Popovici¹, J Gollogly¹

¹The Children's Surgical Centre Phnom Penh, T&O, Phnom Penh, Cambodia

Background: Arthroplasty has consistently shown 'beneficial and often dramatic improvements in quality of life' and in the UK we have minimised infection through the recommendations of papers such as Lidwell's. The CSC has performed 256 THRs since 2008, our primary outcome was all cause of re-operation and our secondary outcomes was assessment of complications.

Methods: All patientes coded as having received a THR in the CSC databases their medical notes and radiographs reviewed. Basic demographics, indication for THR, risk factors for complications, implant combinations and complications were recorded. Statistical analysis was performed using MedCalc.

Results: The mean age was 43, with a M2:1F ratio. The most common pathologies were AVN (44%), OA (11%) and DDH (11%). The revision was 13%, the most common reasons for revision were stem fracture (5.8%), aseptic loosening (4.8% and infection (2.7%). The mean time from implantation to revision was 2.8 years (0-9). A variety of stems have been use over the time period with the best surviving being the Zimmer ML Taper and the UMA Muller stems and the worst performing being the UMA C-Stem which suffered 100% stem fracture. A Kaplan Meier chart was created to demonstrate survivorship. 109 complications were demonstrated in 85 patients (33.2%) the three most common being aseptic loosening (10.5%) stem fracture (5.8%) and dislocation 5.8%) 44 patients had previous surgery which was found to be a significant risk for complications but not infection. OHS initially improved but peaked at year 3 indicating early failure.

Conclusion: There is a clear need for arthroplasty in this working age population with neglected hip pathology with significant pre-operative deformity. Complication rates are declining  suggesting CSC is over the learning curve but cheap poorly manufactured implants cause catastrophic failure which begs the question of how to fund high quality implants to developing countries.

There is NO Conflict of Interest: Yes

172 - Acetabular Fractures in older patients Intervention Trial (AceFIT: ISRCTN16739011)

A Carrothers¹, D Chou¹, J Rawal¹, J Queally¹, P Hull¹

¹Cambridge Uni Hos NHS FT Addenbrookes, Orthopaedics, Cambridge, United Kingdom

Purpose: Displaced acetabular fractures in the older patient present significant treatment challenges. There is evidence that the morbidity and mortality associated with these injuries is similar to the fractured neck of femur cohort. There remains controversy regarding treatment algorithms; varying between conservative management, to fracture fixation and finally ‘fix and replace’ surgical strategies to allow immediate full weight bearing.

Methods: £250,000 NHS funding was secured from NIHR, Research for Patient Benefit (Ref: PB-PG-0815-20054) East of England Research Ethics Committee (Ref: 17/EE/0271). After national consultation, 3 trial arms were included; conservative management, fracture fixation and simultaneous fracture fixation with THA. Inclusion criteria included patients >60 years with displaced acetabular fracture with the following exclusion criteria: open fracture, THA, pre-injury immobility, polytrauma. Primary outcome measure was ability to recruit with EQ-5D-5L at 6 months. Secondary outcome measures at 9 months included OHS, Disability Rating Index, radiographs, perioperative physiological variables including surgery duration, blood loss, complications and health economics.

Results: 11 UK level 1 major trauma centres were enrolled into the trial from December 2017. Full trial recruitment of 60 patients was achieved in December 2019. 496 patients were screened; 379 not eligible and 57 declining participation. 66% of patients recruited were male, median age 76 (range 63-93 years), median BMI 25 (range 18-37), 87% of patients had full mental capacity and 77% were admitted from own home. 75% of injuries were due to a fall from standing height and 60% of fractures were classified as anterior column posterior hemi-transverse. Full data acquisition September 2020.

Conclusion: This unique RCT feasibility study represents the first opportunity to understand the intricacies of each of these agreed treatment modalities, including patient reported outcomes and health economics. The primary outcome measure is likely to show feasibility for a fully powered RCT which will need multinational input.

There is NO Conflict of Interest: Yes

514 - A comparative study of patients presenting for revision of hip or knee replacements, based on whether they were or were not under long term follow-up

S Kingsbury^1,2,3, L Smith⁴, F Shuweildhi⁵, R West⁶, C Czoski-Murray⁶, L Vernon¹, P Conaghan^7,2,1, M Stone^8,3,3,8

¹LIRMM, Leeds, United Kingdom, ²NIHR, Leeds, United Kingdom, ³LMBRC, Leeds, United Kingdom, ⁴Weston Area Health Authority, Weston-Suoer-Mare / Bristol, United Kingdom, ⁵University of Leeds, School of Medicine, Leeds, United Kingdom, ⁶Leeds Institute of Health Sciences, Leeds, United Kingdom, ⁷Biomedical Research Centre, Leeds, United Kingdom, ⁸Chapel Allerton Hospital, Leeds,, Orthopaedic Surgery, Leeds, United Kingdom

Background: This prospective cohort study explored differences in symptoms, healthcare use, reason for revision, and the revision surgery (surgical time, components, length-of-stay) between patients having regular follow-up and those without.

Methods: Data were collected from participants and medical records for the 12 months prior to revision.   Patients with previous revision, metal-on-metal or hip hemi-arthroplasty were excluded. Participants were retrospectively classified to a ‘follow-up’ or ‘no follow-up’ group. Multi-level regression and propensity score matching compared the 2 groups.

Results: 568 patients were enrolled at 35 UK secondary care sites between October 2017 and October 2018 (43.5% male; mean (SD) age 71.86 (9.93) years; 305 hips, 263 knees). No significant inclusion differences were identified between the Follow-up and No Follow-up groups.
For hip revision, male gender (OR 1.975, 95%CI[1.083-3.602], p=0.026) and time-to-revision>10 years (OR 3.804, 95%CI[1.353-10.694], p=0.011) were associated with Follow-up. Periprosthetic fracture (OR 20.309, 95%CI[4.574-90.179], p<0.001) and dislocation (OR 12.953, 95%CI[4.014-41.794], p=0.000) were associated with No Follow-up.
For knee revision, time-to-revision>10 years (OR 2.337, 95% CI[1.007-5.419], p=0.048) and infection (OR 2.946, 95%CI[1.046-8.298], p=0.041) were associated with No Follow-up.
No other significant differences in cost outcomes, length of surgery time and access to a health professional in the 12 months prior to revision were found between the two groups for either hip or knee patients. However, there was a trend for increased length-of-stay and increased surgery time for hip revisions in the No Follow-up group, which was retained when periprosthetic fractures were excluded.

Conclusion: There are differences between patients presenting for revision through follow-up and no follow-up routes. Possible reasons for these differences will be presented.

Implications: This study formed part of the evidence used to inform the development of recommendations for follow-up of hip and knee surgery patients as part of the UKSAFE programme (HS&DR 14/170/96).

There is NO Conflict of Interest: No

538 - Calcar-collar contact during simulated periprosthetic fractures of the femur increases construct stiffness and resistance to fracture but is dependent on the degree of initial separation on implantation: A biomechanical study

J. Lamb¹, O. Coltart², I. Adekanmbi³, T. Stewart², H. Pandit¹

¹University of Leeds, LIRMM, Leeds, United Kingdom, ²University of Leeds, Mechanical Engineering, Leeds, United Kingdom, ³DePuy Johnson and Johnson, Leeds, United Kingdom

Introduction: A calcar collar is associated with a reduced risk of periprosthetic fracture of the femur (PFF) possibly by increasing cortical loading during rotational injuries through calcar-collar contact (CCC). We estimated the effect of calcar collar contact on periprosthetic fracture mechanics and the effect of initial calcar-collar gap on the likelihood of CCC using a cementless femoral stem.

Methods: Three groups of six composite femurs were implanted with a collared cementless femoral stem. Neck resection increased between groups (group 1 = no additional resection, group 2 = 3mm additional resection, group 3 = 6mm additional resection). Distance between collar and the calcar (PCC) were measured and PFF were simulated using an established technique. Fracture torque and displacement were measured. High speed video recording identified when CCC occurred. Logistic regression estimated the odds (OR) of failing to achieve CCC for a given PCC.

Results: Where CCC occurred fracture torque was greater (47.33 [41.03 to 50.45] Nm versus 38.26 [33.70 to 43.60] Nm , p= 0.05), Rotational displacement was less (0.29 [0.27 to 0.39] rad versus 0.37 [0.33 to 0.49] rad, p= 0.07), torsional stiffness was greater (151.38 [123.04 to 160.42] rad.Nm‑1 versus 96.86 [84.65 to 112.98] rad.Nm‑1, p <0.01) and rotational work was similar (5.88 [4.67, 6.90] J versus 5.31 [4.40, 6.56] J, p= 0.6). The median (range) PCC for those trials where CCC was achieved was 0.85 (0.00 to 3.71) mm versus 5.97 (2.23 to 7.46) mm, where CCC was not achieved (p <0.01). Binomial logistic regression estimated OR of failure to obtain CCC increased 3.8 fold (95% Confidence interval 1.6 to 30.2, p <0.05) for each millimetre of PCC.

Conclusions: Calcar collar contact, not just a collar, is crucial to reducing the risk of PFF. Surgeons should achieve a gap of less than 1mm to ensure contact.

There is NO Conflict of Interest: No

Disclosure: Education research grant awarded by DePuy Johnson and Johnson: Implants and equipment for implantation supplied at no cost. Author IA is a DePuy Synthese Johnson and Johnson employee.

558 - Reducing Delays for Surgical Intervention in Patients with Fractured Neck of Femur on Direct Oral Anticoagulants

D. Menon¹, R. Irons¹, S. Ralhan¹

¹Oxford University Hospitals NHS Foundation Trust, Department of Geratology,, Oxford, United Kingdom

Background: Outcomes for neck of femur fracture patients are optimised by early surgical intervention. Current National Institute for Health and Care Excellence (NICE) guidance recommends direct oral anticoagulants (DOACs) should be suspended for 48 hours following the last dose prior to intervention in major orthopaedic surgery. Current practice for proximal femoral fractures in our centre is to proceed with intervention 24 hours following the last DOAC dose. 

Aim: To determine whether a protocol facilitating early surgical intervention in neck of femur fracture patients admitted on a DOAC agent affects post-operative morbidity.

Method: In this single-centre retrospective case-control study, all patients admitted on a DOAC in a 1 year period (December 2017 to November 2018) were identified and matched to non-DOAC controls. Time to surgery, post-operative blood transfusion rate, post-operative haematoma and deep wound infection rate, and estimated peri-operative blood volume (EBV) loss were calculated. 

Results: 456 fractured neck of femur patients were identified. 48 DOAC patients were included in data analysis. 24 DOAC patients (50%) and 107 non-DOAC patient (62%) underwent surgical intervention within 48 hours. In those operated within 48 hours of admission, there was no significant difference in EBV loss between the DOAC and non-DOAC group (881 ± 638ml vs 762 ± 515ml, p=0.40), blood transfusion rate between the DOAC and non-DOAC group (19.2% vs 18.7%, p=0.95), or post-operative complication (haematoma and wound infection) rate (p=0.23).

Conclusion: Peri-operative blood loss, post-operative transfusion rate, and post-operative wound-related complication rate are not significantly increased by early intervention (within 48 hours) in proximal femoral fracture patients admitted on a DOAC relative to a non-DOAC control cohort. This data is based on local guidelines advocating surgical intervention within 24 hours of last DOAC dose. However, further work is needed to establish a specific time to surgery in this patient cohort.

There is NO Conflict of Interest: Yes

684 - A multicentre observational cohort study describing fracture classification and treatment strategies in 575 postoperative periprosthetic femoral fractures around cemented polished taper slip stems in total hip arthroplasty

J. Lamb¹, O. Townsend², S. Jones³, C. Scott⁴, R. Middleton⁵, T. Board⁶, S. Jain¹, H. Pandit¹

¹University of Leeds, Leeds, United Kingdom, ²University Hospital Southampton NHS Foundation Trust, Southampton, United Kingdom, ³Cardiff and Vale University Health Board, Cardiff, United Kingdom, ⁴Royal Edinburgh Hospital, Edinburgh, United Kingdom, ⁵Royal Bournemouth Hospital, Bournemouth, United Kingdom, ⁶Wrightington Hospital, Wigan, United Kingdom

Background: The incidence of periprosthetic femoral fracture (PFF) following total hip arthroplasty (THA) is rising. This study investigates factors associated with classification and treatment methods for PFF around PTS stems.
 
Methods: We investigated 575 PFFs around PTS stems: Exeter (48.5%), CPT (40%), C-stem classic (7.7%) and C-stem AMT (3.8%). Continuous variables were compared with unpaired t-tests and Mann-Whitney U tests and categorical variables with Chi-squared tests. Multinomial logistic regression estimated the odds ratio (OR) of Vancouver grade. 
 
Results: Mean (SD) age was 77.79 (11.35) years and 54.3% cases were female. Median (IQR) time to fracture was 3.65 (1.05-7.02) years. Vancouver grade was A (2.6%), B1 (53%), B2 (24.9%), B3 (6.6%) and C (12.9%). Treatment included fixation (48.2%), revision (46.3%), nonoperative (3.0%), excision arthroplasty (0.5%), amputation (0.3%) and unrecorded (1.8%). 
 
Median (IQR) years to fracture differed with age (years): 1.96 (0.89-4.84) under 60, 2.51 (0.71-6.20) between 60-80 and 5.16 (1.92-8.20) over 80 (p < 0.001). Median (IQR) years to fracture differed by stem brand: C-stem AMT 0.63 (0.24-1.65), CPT 2.83 (0.92-6.49), C-stem classic 3.13 (0.34-5.24) and Exeter 4.24 (1.24-8.40, p<0.001).
 
Increasing age gave an OR of 1.03 per year (95% CI 1.01-1.06, p=0.02) for type C versus type B fractures. Males were four times less likely than females to get type C versus type B fractures (OR 0.25, 95% CI 0.14-0.45, p<0.001). Similar numbers of B1 and B2 fractures underwent revision (44.0% versus 42.5 %, p>0.05). Treatment strategies were not influenced by age, gender or interprosthetic fracture (p>0.05).
 
Conclusions: A shorter time to fracture was seen with younger patients and specific stem brands. Fracture classification was influenced by age and gender. Similar numbers of B1 and B2 fractures underwent revision highlighting a lack of treatment consensus.
 
Implications: Further study is required to determine the optimal treatment for type B fractures.

There is NO Conflict of Interest: Yes

690 - Predictors of Mid-late Term Revision of Total Hip Replacement: a Nation-wide Retrospective Cohort Study (UK SAFE)

A. Judge¹, C. Garriga-Fuentes², S. Kingsbury³, L. Smith⁴, M. Porter⁵, R. Pinedo-Villaneuva², N. Arden², P. Conaghan³

¹University of Bristol, Musculoskeletal Research Unit, Bristol, United Kingdom, ²Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences (NDORMS), University of Oxford, Oxford, United Kingdom, ³Leeds Institute of Rheumatic and Musculoskeletal Medicine University of Leeds, Leeds, United Kingdom, ⁴Health & Applied Sciences, University of the West of England, Bristol, United Kingdom, ⁵Centre for Hip Surgery, Wrightington Hospital, Wrightington, United Kingdom

Objective: Identify which patients are most likely to require mid-late revision surgery to inform targeted follow-up.

Methods: Setting: Primary care using Clinical Practice Research Datalink (CPRD) data and secondary care using National Joint Registry data linked to English Hospital Episode Statistics (HES) and Patient Reported Outcome Measures (PROMs). Patients: Primary elective total hip replacements (THR) aged ≥18. Event of interest: Revision surgery ≥5 years after primary THR. Statistical methods: Cox regression modelling to ascertain influential factors of mid-late term revision. Hazard ratios (HR) and 95% confidence intervals (CI) assessed the association of sociodemographic factors, comorbidities, medication, surgical variables and PROMs with mid-late term revision.

Results: NJR-HES-PROMs data was available from 2008-2011 on 142,275 THR. The CPRD-HES data covered a longer period from 1995-2011 on 22,312 THR. Patients had a minimum 5-years post primary surgery to end 2016. Age and gender distribution were similar across both datasets; mean age 70 years, 62% female. In the NJR there were 3,582 (2.5%) revision procedures over a median time-to-revision 1.9 years (range 0.01-8.7 years), of which 598 (0.4%) were mid-late term revisions. In CPRD 982 (5.8%) revisions over median time-to-revision 5.3 years (range 0 -20 years), with 520 (3.1%) mid-late term revisions. Older age was related to significantly lower revision after 5 years (HR: 0.97; 95% CI: 0.96-0.98). Ceramic-on-ceramic bearings (0.70; 0.54-0.91) and ceramic-on-polyethene (0.75; 0.57-0.98) were protective for mid-late revision compared to metal-on-polyethylene bearings. Femoral head size >28mm diameter had higher mid-late term revision risk (≥44 mm: 2.74, 1.17-6.40). Pre-operative hypertension (0.77; 0.61-0.96) conferred a lower risk, whilst hyperlipidaemia (1.46; 1.09-1.95), antidepressant medication (1.38; 1.14-1.67) and steroid injections (1.32; 1.05-1.66) increased mid-late revision risk.

Conclusion: Younger age, metal-on-polyethylene bearings and larger femoral head sizes may be relevant factors in deciding which patients require extended follow-up based on their mid-late term revision risk.

There is NO Conflict of Interest: Yes

718 - Femoral heads for histology in neck of femur fracture: a proposed protocol for guiding investigation

z. sadozai¹, M. Al-Ashqar¹, H. Clarke¹, N. Pennington¹

¹Huddersfield Royal Infirmary, Huddersfield, United Kingdom

Background: Low-energy neck of femur (NOF) fractures commonly afflict the elderly. In some cases the underlying pathology is sinister, such as malignancy, and can be further investigated by histological examination. There is little or no guidance on the indications for sending these samples for histology either at a local-hospital level or in the current literature. Our study has set out to review the indications for sending samples to histology and the management outcomes, and to propose a protocol guiding histological investigation.

Method: We performed a retrospective single-centre study of all femoral heads sent for histology for NOF fractures between January2017 until September2019. All patients who sustained an acute fracture and had their femoral head sent for histology were included. Case-notes from electronic patient records and local histology results were reviewed. Patient demographics,indications for sending, histology results, time taken for results and management outcomes were recorded. We designed a local protocol guiding which samples to send to histology.

Results: A total of 90 samples of femoral head were sent for histology in 3 years. 11 out of the 90 femoral heads were positive for malignancy. The mean number of days until final results were available was 41 (10-86). The most common indication for sending a sample was history of previous or current cancer (71%). No positive malignancy results were seen in any samples sent that did not fit our proposed protocol. 3 out of the 11 positive results were subsequently managed by discussion in the cancer multidisciplinary team, whereas the remaining 8 did not lead to any change in management.

Conclusion: We recommend a protocol as cost-effective screening criteria for deciding when to send femoral heads for histology. History of previous malignancy alone is a poor indicator for a positive result. Results can be time consuming to process however can lead to further appropriate oncological management.

There is NO Conflict of Interest: Yes

788 - Perioperative Administration of Tranexamic acid in Hip fracture Surgery (The PATHS Study): National Audit of Current Practice

T. Naylor¹, A. Berg², D. Johnson³, P.S.C. PATHS Study Collaborators⁴

¹Manchester University NHS Foundation Trust, Department of Trauma and Orthopaedics, Manchester, United Kingdom, ²Health Education England (Northwest), Manchester, United Kingdom, ³Stockport NHS Foundation Trust, Department of Trauma and Orthopaedics, Stockport, United Kingdom, ⁴PATHS Study Collaborators, Manchester, United Kingdom

Introduction: Neck of femur (NOF) fractures are associated with significant morbidity and mortality. Concomitant anaemia is also associated with morbidity and is often targeted by national quality improvement strategies. Evidence indicates tranexamic acid (TXA) administration in NOF fracture surgery reduces blood loss and need for transfusion, with no increase in complications. The aim of this study was to establish current TXA administration practice in patients undergoing surgery for NOF fractures in the United Kingdom.

Materials and Methods: A multicentre prospective study was conducted over a two-week period from 4th–18th March 2019. Pre-operative, intra-operative and post-operative data was collected locally and submitted via an online platform for central analysis.

Results: Data for 917 patients was submitted by 239 collaborators from 66 institutions. 98.4% were treated surgically. 48.04% of those eligible received TXA peri-operatively. Administration rates varied from 0-100% between centres. 13.6% of institutions had a protocol for TXA in NOF surgery. 57.4% undergoing arthroplasty received TXA and 38.2% for internal fixation (p<0.01). 92.9% of those receiving TXA had 1-gram IV at time of anaesthesia.

Discussion: Wide variation in the administration of TXA between hospitals and procedures has been demonstrated. Administration rate was higher in arthroplasty than fixation procedures. Most centres do not have a protocol for TXA administration in NOF patients.

Conclusion: There exists wide variability in TXA administration rates despite supportive evidence. Recommendations of 1-gram IV TXA peri-operatively for patients undergoing NOF fracture surgery are made but further randomised controlled trials may be required to support a national policy.

There is NO Conflict of Interest: Yes

930 - A comparative study of hip fracture care and outcomes in major trauma centres versus trauma units

J. Lukic¹, A. Rajeev¹, B. Tyas¹, K. Singisetti¹

¹Queen Elizabeth Hospital, Orthopaedics, Gateshead, United Kingdom

Introduction: Hip fractures in elderly patients are managed at both major trauma centers (MTC) and trauma units (TU). Previous evidence has demonstrated the importance of early surgery to reduce the morbidity and mortality related to the injury. The aim of this study is to compare the ‘time to theatre’ and ‘30 day mortality’ in TUs versus MTC in UK.

Methods: A retrospective review of prospectively collected data on NHFD was performed. The average ‘time to theatre’ in hours and ‘30 day mortality’ of all hospitals were analysed between January and December 2018. Further subgroup analysis was done to check for any regional variations; in each instance a Shapiro-Wilk test was used to check for normal distribution, followed by a one-way ANOVA with a Tukey’s post hoc test.

Results: Data from 158 hospitals in England (ENG), Wales (WAL) and Northern Ireland (NI) were used; 18 of which were MTC. There were 57,936 operative cases in TUs and 8606 in MTC’s. The mean time (hours) to surgery from presentation was 32.51 and 32.64 for TUs and MTC respectively (p=0.513).

There was no significant difference in ‘30 day mortality’ (p=0.635) between TUs (6%) and 5.7% MTC’s (5.7%), MTC’s and TUs in ENG, WAL and NI (p=0.555), and MTC and WAL, NI and the different regions of ENG (p=0.209).

A significant difference was observed, between the regional practice for TUs versus MTC’s in ENG, WAL and NI (p=0.001) and between MTC’s and TUs in WAL, NI and the different regions of ENG (p=0.001), with patients waiting significantly longer in NI for their procedure (mean=60.25 hours, p=0.001)

Conclusion: There was no significant difference in time to surgery or 30 day mortality between TUs and MTC’s, demonstrating comparable hip fracture care, despite MTCs need to prioritise more serious injuries.

There is NO Conflict of Interest: No

1023 - Sacro-Femoro-Pubic Angle used in predicting high-risk cases of THR dislocations

K. Thakre¹, A. Kanitkar¹, A. Razak¹, A. Malik¹, R. Mohan¹, A. Ahmed¹, S. Sharma¹

¹Pennine Acute NHS Trust, Trauma & Orthopaedics, Manchester, United Kingdom

Background: The sagittal spinopelvic balance plays an important role in the surgeries around the pelvis. The parameters like pelvic tilt and sacral slope are calculated on lateral radiographs of the lumbosacral spine and are helpful to differentiate balanced and unbalanced pelvis. Recently, a few studies have found a correlation between the pelvic tilt and Sacro-Femoro-Pubic angle (SFP angle) which is measured on AP radiograph of the pelvis. The objective of this study was to evaluate the Sacro-Femoro-Pubic angle (SFP angle), which is a direct reflection of the pelvic tilt, in patients who had total hip replacements (THR).

Methods: This is a retrospective study of 80 patients who had THR. They were divided into two subgroups, one with dislocations (n-40) and other without any dislocations (n-40). We evaluated the SFP angles on AP radiographs of the pelvis and compared them in both the groups. The Pelvic Tilt (PT) which is a predictor of an unbalanced and balanced pelvis, can be calculated by the formula: PT= 75- SFP angle.

Results: The average SFP angle was 60.95 in dislocated THR compared to 65.78 in non-dislocated THR.   The PT thus calculated in dislocated vs non-dislocated groups was 14.05 vs 9.22. There was no significant difference between the left and right SFP. The relationship between SFP angle and PT was analysed by Pearson’s correlation analysis and linear regression analysis.

Conclusion: The SFP angle gives an advantage of predicting the PT on AP radiograph of the pelvis which can predict the risk of dislocations after THR. To the best of our knowledge, this is the first study in the available English literature assessing the PT and SFP angles in dislocated THR and non-dislocated THR.

There is NO Conflict of Interest: Yes

1055 - Hemiarthroplasty Hip Dislocation- An Overview of Management and Outcomes

P.K. Shanthi Ashokkumar¹, S. Khan², J. Carter³, J. Dsouza⁴, P. Chandran⁵, R. Sanger¹

¹Warrington and Halton Hospital NHS Foundation Trust, Trauma and Orthopaedics, Warrington, United Kingdom, ²Whiston Hospital, Prescot, United Kingdom, ³Warrington and Halton Hopsital NHS Foundation trust, Warrington, United Kingdom, ⁴Warrington and Halton Hospital NHS Foundation Trust, Warrington, United Kingdom, ⁵Warrington and Halton Hospital NHS Foundation trust, Trauma and Orthopaedics, Warrington, United Kingdom

Background: Hip hemiarthroplasty is a recognised method of managing intra-capsular fracture neck of femur. Dislocation of hip hemiarthroplasty management can be complex and leads to increase in morbidity and mortality.
 
Method: Aim: To evaluate the incidence of prosthetic hip dislocation following hip hemiarthroplasty for displaced fracture neck of femur and to evaluate their outcomes.
Between 2016-2019, 444 patients were treated with hip hemiarthroplasty for displaced intra-capsular fracture neck of femur. Twelve patients (2.5%) developed dislocation of the hip hemiarthroplasty post-operatively, 9(66.6%) were females; mean age was 79(61-92) years.
 
Results: Ten dislocations (83.3%) occurred within 6 weeks of primary surgery. The initial management was MUA for 10 patients, 1 had Open reduction and 1 had primary revision surgery.
In the 10 patients who had MUA, 4 (40%) failed, of these two proceeded to have excision arthroplasty, one had constrained total hip arthroplasty.
Of six (60%) patients who had successful closed manipulation, 5 had further dislocation and re-surgery; 3 converted to total hip arthroplasty and 2 to excision arthroplasty.
All patients with revision arthroplasty were fully weight bearing while those with excision arthroplasty had limited mobility with hoist transfer at the time of discharge.

Conclusion: 

1. Incidence of dislocation following hip hemiarthroplasty was 2.5% of which 83% dislocated within six weeks of primary surgery.
2. One patient had MUA, 5 patients had Revision arthroplasty and 6 patients had excision arthroplasty as the definitive procedure.
3. Hemiarthroplasty hip dislocation had a 25% 90 day mortality.
4. Relocation of hip including closed and open relocation is generally unsuccessful (90%) resulting in further dislocations. For patients with dislocated hip hemiarthroplasty, it is recommended to consider a definitive surgery at the first instance to prevent revisits to theatres.
5. Revision arthroplasty results in better mobility and function and has lower mortality than excision arthroplasty in patients considered fit for major surgery.

There is NO Conflict of Interest: Yes

1057 - Prevalence of Femeroacetabular Impingement Syndrome in Elite Gaelic Games Players: A Cross-sectional Study Utilising Magnetic Resonance Imaging

C. Mc Donald¹, J. Moore¹, S. Flynn¹, E. Murphy¹, S. Gilmartin¹, P. O'Neill¹, J. O'Byrne¹, S. Eustace¹

¹National Orthopaedic Hospital, Cappagh, T&O, Dublin, Ireland

Background: Femeroacetabular impingement (FAI) is said to effect 15% of the general population, and has been increasingly recognised as a cause of hip pain in athletes. Hip impingement can lead to early onset osteoarthritic and degeneration of the hip joint itself. Identification of the prevalence of impingement in elite Gaelic games players has never been reported in the scientific literature. Impingement can be thought of as a triad of symptoms, signs and radiographic findings. Identification can thereby be assessed by combination of imaging (MRI) and clinical history and examination.

Aim: We aim to identify the prevalence of FAI syndrome in elite Gaelic Games players via clinical examination and MR imaging.

Methods: All existing senior intercounty games players were invited to partake in an anonymous sports medicine study. Subjective functional hip scores were collected for all participants (HAGOS and the IHOT33 questionnaire). Hip examination and impingement tests were subsequently performed. Finally all participants underwent an MRI pelvis. Radiographic evidence of cam impingement was defined as an alpha angle greater then 56*, with pincer impingement identified as lateral centre edge angle > 36*. Impingement syndrome was defined as the presence of hip symptoms, impingement sign positive and evidence of impingement on higher modality imaging (MR).

Results: Fifty one participants were included in this study. The prevalence of FAI syndrome was 24%. The prevalence of radiographic impingement was 39%. Of the asymptomatic population, 43% had evidence of radiographic impingement. The mean IHOT 33 score calculated for all participants was 89.0. Forty participants (78.4%) examined were FADIR positive. Ten of 51 participants (19.6%) had normal pelvis MRIs.

Conclusion: This is the first descriptive study to investigate the prevalence of FAI in a Gaelic athletic population. It provides new information on this study group. This information can be used to inform practice in the future.

There is NO Conflict of Interest: Yes

1074 - Long-Term Results of Revision Total Hip Arthroplasty Using a Modern Extensively Porous Coated Femoral Stem

C. Wallace¹, J. Chang¹, B. Kayani¹, P. Moriarty¹, F. Haddad¹

¹UCLH, London, United Kingdom

Background: The use of an extensively porous coated monoblock femoral stem for revision total hip arthroplasty is well established. The aim of this study is to report the long-term survivorship and functional outcomes of these implants. 
 
Method: This is a prospective study of femoral stem revisions using a contemporary, uncemented extensively porous coated cobalt-chrome monoblock stem with minimum 10-year follow-up. All patients between 2001-2006 who underwent femoral stem revision with the study implant were included. Fifty-six patients were included with a mean age of 66.4 ± 9.3 years at the time of surgery. The mean time interval from index procedure was 9.8 ± 2.9 years. 37 females (66.1%) and 19 males (33.9%) were included in the study. Harris Hip Score (HHS), Western Ontario and McMaster Universities Index (WOMAC), and University of California Los Angeles (UCLA) activity scores were recorded pre-operatively and at latest follow-up. Radiographs were analysed for evidence of loosening, subsidence, and osteolysis and bony union. 
 
Results: Fifty-six patients with 56 femoral stem revisions were identified. Indications for revision included aseptic loosening (33), prosthetic joint infection (13), and periprosthetic fracture (10). Mean follow-up was 13.2 ± 2.17 years. Significant improvement in HHS (85.1 ± 1.77 vs. 51.8 ± 2.3, p<0.001), WOMAC (17.6 ± 0.77 vs. 33.3 ± 0.8, p<0.001), and UCLA activity (5.25 ± 0.2 vs. 2.7 ± 0.36, p<0.001) scores were found at latest follow-up compared to pre-operative.  Fifty-four patients (98%) achieved stable bony ingrowth on radiographic analysis and all patients treated for periprosthetic fracture (13) achieved bony union of the fracture. There were no mechanical failures and no femoral stem re-revisions. 
 
Conclusion: Revision of the femoral component with a contemporary extensively porous coated cobalt chrome femoral stem has excellent functional outcomes, radiographic outcomes, and long-term survivorship with minimal complications.

There is NO Conflict of Interest: No

Disclosure: Prof FS. Haddad reports consultancies and royalties from Smith & Nephew, Corin, MatOrtho, and Stryker, and payments for lectures (including service on speakers bureaus) from Smith & Nephew and Stryker. None of the authors have any conflicts of interest related to this paper. No funding was received for this paper.

1146 - Relationship Between the Transverse Acetabular Ligament & The Psoas Fossa. Implications for iliopsoas Impingement Against the Acetabular Component. A Cadaver study

K.H. Sunil Kumar¹, S. Kutty²

¹Addenbrookes Hospital, Trauma and Orthopaedics, Cambridge, United Kingdom, ²Princess Alexandra Hospital, Trauma and Orthopaedics, Harlow, United Kingdom

Background: Optimal acetabular component position in Total Hip Arthroplasty is vital for avoiding complications such as dislocation, impingement, abductor muscle strength and range of motion. Transverse acetabular ligament (TAL) and posterior labrum have been shown to be a reliable landmark to guide optimum acetabular cup position. There have been reports of iliopsoas impingement caused by both cemented and uncemented acetabular components. Acetabular component mal-positioning and oversizing of acetabular component are associated with iliopsoas impingement. The Psoas fossa (PF) is not a well-regarded landmark to help with Acetabular Component positioning. Our aim was to assess the relationship of the TAL and PF in relation to Acetabular Component positioning.

Methods: A total of 12 cadavers were implanted with the an uncemented acetabular component, their position was initially aligned to TAL. Following optimal seating of the acetabular component the distance of the rim of the shell from the PF was noted. The Acetabular component was then repositioned inside the PF to prevent exposure of the rim of the Acetabular component. This study was performed at Smith & Nephew wet lab in Watford.

Results: Out of the twelve acetabular components that were implanted parallel to the TAL, all had the acetabular rim very close or outside to the PF with a potential to cause iliopsoas impingement. Alteration of the acetabular component position was necessary in all cadavers to inside the PF to prevent iliopsoas impingement. It was evident that the edge of PF was not aligned with TAL.

Conclusion: Optimal acetabular component position is vital to the longevity and outcome following THA. TAL provides a landmark to guide acetabular component position. We feel the PF is a better landmark to allow appropriate positioning of the acetabular component inside bone without exposure of the component rim and thus preventing iliopsoas impingement at the PF.

There is NO Conflict of Interest: Yes

1150 - The ceiling effect after hip arthroplasty: important differences in return to higher level activity are missed by the Oxford Hip Score

T. Edwards¹, B. Keane¹, A. Garner¹, K. Logishetty¹, J. Cobb¹

¹Imperial College London, MSk Lab, London, United Kingdom

Background: The Oxford Hip Score (OHS) is widely used as the primary outcome measure, by the NHS and for trials, including randomised trials of different forms of hip arthroplasty. The ceiling effect of the OHS may limit its ability to discriminate between postoperative hip arthroplasty patients as the modal score is 48/48. This study investigates the use of the Metabolic Equivalent of Task (MET) score and its ability to distinguish patients scoring maximally on the OHS.
 
Method: OHS, EuroQol-5D index (EQ-5D), and the MET were prospectively recorded in 98 primary hip resurfacing arthroplasty (HRA) and 105 primary total hip arthroplasty (THA) procedures pre-operatively and at 1-year follow up. A sub-cohort of 50 patients scoring 48/48 on the OHS postoperatively were matched in a 1:1 ratio HRA:THA for age, BMI, preoperative OHS score & preoperative MET. The distribution of each metric was described alongside differences between the two groups using the three scores before surgery and at 1-year follow-up.
 
Results: As preoperative scores, both OHS and EQ-5D are normally distributed without significant skew, and satisfactory kurtosis. Postoperatively, both scores exhibit significant negative skew, high kurtosis, and large ceiling effects: OHS (40.4%) & EQ5D (52.7%). The MET had a small floor effect pre-operatively (27%) but was normally distributed postoperatively. In the sub-cohort analysis of patients scoring 48/48 on the OHS, using the MET, HRA patients scored 12.7 while THA patients scored 10.5. This 20% difference was both clinically and statistically significant (p=0.01).  
 
Conclusion: The MET score is normally distributed in patients following hip arthroplasty, recording levels of activity which are undetectable using the OHS. As a simple valid patient-centred activity measure, it should be considered in addition to conventional PROMs scores for patients, clinicians, and health economists who wish to capture the entire benefit experienced following hip arthroplasty.

There is NO Conflict of Interest: Yes

1151 - Multi-Planar Reconstruction As A Novel Method of Measuring Femoral Neck Anteversion on CT Rotational Profile Scan

R. Mansouri¹, Z. Nawaz¹, H. Chissell¹, T. Amies²

¹Frimley Health Foundation Trust, Trauma & Orthopaedics, Frimley, United Kingdom, ²Frimley Health Foundation Trust, Radiology, Frimley, United Kingdom

Background: The current gold standard to measure the version values of femur is CT rotational profile scan at the level of hip and knee. However, determining the axis of femoral neck is challenging as the CT cuts do not show femoral neck in its entire length and therefore neck relationship with femoral head and greater trochanter is not clear.

Objectives: Multiplanar reconstruction is a function available in some digital radiology software platforms. It will allow the proximal femoral CT cuts to be reformatted in the plane of femoral neck and head. We hypothesised that using a multiplanar reconstruction will allow better accuracy of femoral neck anteversion measurement and therefore better inter- and intra-observer reliability

Design and Methods: CT rotation profiles of 10 patients with different femoral anteversion values was used in this study. A group of orthopaedic trainees and consultants were asked to measure the femoral neck anteversion using traditional method. They were then given a tutorial on how to use multiplanar reconstruction function and were asked to perform the measurements again. The measurements were repeated using both methods in 4 weeks interval. All observers were blinded to their own prior measurements and to those of other observers.

Results: Intraclass correlation coefficients (ICC) were used to determine the inter-observer and intra-observer reliabilities. 95% prediction limits for the errors in measurements were calculated. For the femoral neck anteversion measurement using the traditional method a mean ICC value of 0.86 was determined for inter-observer reliability and a mean ICC value of 0.90 for intra-observer reliability. For the multiplanar reconstruction method a mean ICC value of 0.93 was determined for inter-observer reliability and a mean ICC value of 0.95 for intra-observer reliability.

Conclusion: Using multiplanar reconstruction reformatting improves the inter- and intra-observer reliability of measuring femoral neck anteversion.

There is NO Conflict of Interest: Yes

1203 - Dual Mobility Cups: Long term Outcome in Complex Primary and Revision Hip Arthroplasty

K. Abdelhakim Edres¹, S. Mirza¹, N. Shah¹

¹Worthing Hospital, Western Sussex Hospitals Trust, T&O, Worthing, United Kingdom

Background: The risk of instability and dislocation following complex Primary or Revision Total Hip Arthroplasty (THA) is higher than average; this impacts the future re-revision surgery and patients’ quality of life and satisfaction. Dual mobility socket is considered an alternative to avoid this complication. We therefore carried out this study to evaluate whether dual mobility socket fulfils these aims at long-term.

Methods: We carried out a retrospective analysis of prospectively collected data of patients who had cemented dual mobility (SERF) sockets. Records were evaluated for demographics, comorbidities and body mass index. The Oxford Hip Score (OHS) and the EQ5D were obtained for functional outcomes including satisfaction. The primary outcome measure was dislocation with secondary outcomes including infection, aseptic loosening and other complications. Recent x-rays were evaluated for loosening.

Results: There were 108 complex primary and 133 revision THAs using the cemented SERF cup in 237 patients. 35 patients were deceased, leaving 202 patients with 206 hips for final evaluation at 3 to 11 years follow up. 98 were complex primary with average age of 85 years and 108 were revision THA with average age of 81 years. There were 171 female and 35 male patients. The average OHS was 37 and EQ5D was 77. There were no dislocations or intra-prosthetic complications. There were two deep infections. Radiological analysis using Kaplan-Meirr method showed 100% survival at 11 years.

Conclusion: This is the largest series of exclusive cemented dual mobility socket used for complex primary and revision THAs. Our results show excellent outcomes in this challenging group of patients, achieving satisfactory stability with low complication rates. This exclusive study also looks at patient reported outcome measures, indicating satisfactory outcomes and satisfaction for dual mobility sockets in at medium to long term.

There is NO Conflict of Interest: Yes

1237 - Can hip precautions prevent early hip dislocation? A systematic review and meta-analysis of the literature examining hip precautions in the anterolateral and posterior approach in THA

Y.H. Mirza¹, V. Kandhari¹, K. Mohanty¹

¹University Hospital Wales, Cardiff, Trauma and Orthopaedics, Cardiff, United Kingdom

Aim: To evaluate the influence of hip precautions on the incidence of early hip dislocation after total hip arthroplasty performed either using an anterolateral or posterior approach.

Methods: Pubmed, EMBASE (1974-2020) and OVID (1946-2020) databases were searched using the terms total hip arthroplasty as well as MeSH terms. Included studies provided details of the use of hip precautions after primary THA and reported early incidence of hip dislocation. Studies omitting details of hip precautions, the rates of hip dislocation, or those performed for revision THA and non-English language studies were excluded. The systematic review was registered with the PROSPERO database

Results: 18 studies were included, comprising 17,286 THAs. In 10,160 THA patients, either reduced or no hip precautions were used.
Four studies reported primary THAs performed exclusively via the anterolateral approach, whilst 9 described a posterior approach.
The remaining 5 studies described a multitude of approaches including 2 incision anterior to a posterior mini-incision amongst others.
In the posterior approach group, there were 9007 patients, of whom 4492 were not subject to hip precautions. 81 dislocations were observed in those without hip precautions, a risk ratio of 1.80%, whilst 89 were observed in those subject to hip precautions, a risk ratio of 1.72%. A pooled analysis of studies from the posterior approach demonstrated an odds ratio of 0.90, 95% confidence interval of 0.66-1.22, p= 0.50. From the anterolateral approach cohort, there were 4148 patients, of whom 2354 were not subject to hip precautions. 43 dislocations were observed in those without hip precautions, a risk ratio of 1.82%. An adjusted pooled analysis of studies demonstrated an odds ratio of 1.14, 95% confidence interval of 0.356-3.66, p= 0.82.

Conclusion: We conclude that the early hip dislocation incidence after anterolateral or posterior primary THA is not influenced by the practice of hip precautions.

There is NO Conflict of Interest: Yes

1283 - Dislocation of total hip replacement in the fracture neck of femur – Does surgical approach or dual mobility implant matters?

P. Goru¹, S. Haque¹, M. Hamed¹, S. Shah¹

¹Manchester Royal Infirmary NHS Foudation Trust, Trauma and Orthopaedics, Manchester, United Kingdom

Introduction: Total hip replacement in the neck of femur fracture Is always surgically challenging for the hip surgeons. NICE Hip fracture management clinical guidelines defined clear criteria for patients who need a total hip replacement for the neck of femur fracture. It also recommended the anterolateral approach over the posterior approach.

Aim: To see the dislocation rate in patients with the fracture neck of femur who underwent total hip replacement with Standard bearing compared to Dual mobility bearing surface. Also compare with national dislocation rate.

Methods: Initial audit data collected retrospectively from Feb 2017 till April 2019 in Manchester Royal Infirmary from the electronic records database and clinical documentation. Patients included were the neck of femur fracture who underwent a total hip replacement. Loop audit data collected prospectively from April 2019 till now which followed the recommendation of Dual mobility cup for total hip replacement.

Results: Out of 53 Patients included in the initial audit, 7(13.2 %) THR dislocations recorded. 6(20%) out of 30 patients underwent a posterior surgical approach and 1 (4.34%) of 23 underwent a Lateral approach were dislocated. 6 (13.95%) out of 43 traditional cemented hip replacement and 1(10%) of 10 dual mobility cups were dislocated. 2(20%) of 10 femoral head size 28mm, 5(21.7%) of 23 femoral head size 32mm were dislocated. No dislocations with 36 mm head. Subsequent audit data of 20 hip replacements following neck of femur fracture with no dislocations by using dual mobility cup.

Conclusion: Our series demonstrates a significant reduction of dislocation with the use of Dual mobility cup in the neck of femur fractures who underwent THR. We recommend dual mobility cup for posterior approach THR and Anterolateral approach with standard hip with size 36 head. The surgical approach using posterior or lateral didn’t show any effect on results.

There is NO Conflict of Interest: Yes

1311 - If it is expensive, is it any better? Comparison of Palacos R+G with Copal C+G sensitivities in infected hip hemiarthroplasties between 2017-2020 at a tertiary centre.

M. Kumar¹, C. Lodge², G. Mohrir², G. Whitwell²

¹Leeds Teaching Hospitals NHS Trust, Leeds, United Kingdom, ²Leeds Teaching Hospitals NHS Trust, Trauma & Orthopaedics, Leeds, United Kingdom

Background: Hip fractures are one of the commonest encountered fragility fractures in the UK with more than 85% of patients receiving cemented arthroplasty where eligible. Copal C+G had shown to reduce post arthroplasty infection rates from 5.6% to 1.7% (Sprowson et al).  Our standard cement is Palacos R+G. The study aims to review the potential financial impact and healthcare benefits of a cement switch to Copal C+G.

Method: Hip fracture patients who underwent hemiarthroplasty between Jan’2017 & Apr’2020 and had a subsequent deep wound infection were retrospectively identified. Electronic records of these patients were reviewed for microbiological growth and antibiotic sensitivities from intra-operative samples. The sensitivities were then compared with the constituents of both cements. 

Results: A total of 1017 hip hemiarthroplasties were performed during the period. Amongst them, 14 patients (1.4%) were identified to have a deep infection requiring operative intervention and long term antibiotics. Mean age of patients in the infected cohort was 86.2 years. Single organism were isolated in only 6 samples (43%). The remainder of the samples had more than one microbial growth (57%). Staphylococcal species were most commonly isolated (10/14) followed by Proteus species (4/14), and E.coli (4/14). Most isolates were sensitive to Ciprofloxacin (42.8%) & Teicoplanin (35.7%). None of the isolates was sensitive to Clindamycin. Mean duration of antibiotic therapy was 6 weeks (IV+PO). Excision arthroplasty was performed in 5 patients (35.7)%. The total estimated additional financial burden of infective hemiarthroplasties during the period was over £100,000 for the Trust.

Conclusion: Infected hip hemiarthroplasties are a massive economic burden for the Trust. As Copal C+G carries an additional premium of £100 per patient over Palacos, its introduction would have added an additional £101,700 to the cost of hemiarthroplasties without any significant improvement in infection rates.

There is NO Conflict of Interest: Yes

1324 - What Are The Correct Indications For Sending A Femoral Head For Histology? A Retrospective Analysis Of Two Centres In West Yorkshire, UK

M. Kumar¹, M. Al-Ashqar², M. Abdelrahim², S. Nisar², C. MacEachern²

¹Leeds Teaching Hospitals NHS Trust, Leeds, United Kingdom, ²Leeds Teaching Hospitals NHS Trust, Trauma & Orthopaedics, Leeds, United Kingdom

Background: Femoral heads are sent for histological analysis following trauma hip arthroplasty to exclude malignant bone metastasis. The paucity of evidence on the indications for sending a femoral head for histology has led to a discrepancy in practice across centres in the UK. Femoral head histology (FHH) is a time, cost and labour intensive procedure, often requiring multiple cycles of decalcification. This study aims to establish a correlation between FHH indications and outcomes, produce a robust cost analysis and develop further guidance on the correct indications.

Method: Femoral heads from trauma arthroplasties sent for histology during 2016-2018 in a district general hospital and a major trauma centre were retrospectively identified. The electronic records of the patients were reviewed for indications for the test, changes in patient management, cost estimations and labour time.
 
Results: We identified 120 patients that met the inclusion criteria. 75 patients (62.5%) had known previous or current cancer. The commonest indication was exclusion of malignancy in suspected pathological neck of femur fracture (NOF). Eighty seven patients (72.5%) had a low energy and 33 patients (27.5%) had atraumatic NOF. The mean age was 76.9 years. Twenty patients (16.7%) were positive for malignancy, of whom 16 patients (80%) had active cancer with no alteration in management. The remainder had additional indications as atraumatic fracture, pre-injury pain or abnormal bone intra-operatively. Three patients (2.5%) had a maiden diagnosis of cancer based on FHH and underwent subsequent staging and treatment. The minimum estimated cost was £20,000 and a minimum 300 manhours of labour.

Conclusions: Femoral head histopathological studies based on a history of previous/active cancer is not cost-effective and does not lead to a change in clinical management. Patients with a new diagnosis of cancer based on FHH leading to a clinically relevant change in management had other more sensitive indicators as atraumatic fractures & pre-injury pain.

There is NO Conflict of Interest: Yes

1339 - The Value of Routine Femoral Head Histology in Neck of Femur Fractures

K. Mazur¹, S. Bonczek¹, A. Ng¹

¹Pinderfields General Hospital, Trauma and Orthopaedics, Wakefield, United Kingdom

Hip fractures are very common injuries among the elderly population. Many of these patients often have complex medical backgrounds including malignancy. Suspicious radiographic findings, no history of preceding trauma, pre-existing pain and history of cancer may imply a pathological nature of fracture warranting further investigation. In 2016, The Royal College of Pathologists recommended that all fractures below articular surfaces should be examined histologically to identify the underlying pathology. However, there is still much debate amongst clinicians regarding routine histological analysis of femoral heads following surgery for neck of femur fractures. Our aim was to ascertain if the histological findings correlate with diagnosis and influence patient treatment. 
 
We have conducted a retrospective study of all femoral head samples sent for histology over a 4-year period in patients who underwent hip hemiarthroplasty for neck of femur fracture at a District General Hospital. We investigated the indications for sending histology samples, the results of the investigations, duration of sample processing and patient outcomes. 
 
Out of 59 femoral heads sent for analysis, 7 were positive for malignancy. All positive samples had previous radiological confirmation of malignancy and patients received oncology input prior to histology results. In none of these cases has the histology contributed to or altered patient care. The most common indication for sending specimens was previous history of cancer or current cancer treatment. The average time to process samples was 16 days.

In conclusion, routine femoral head histology in patients with neck of femur fractures is a costly and time-consuming investigation, which may not directly contribute to patient’s treatment and is, therefore, of limited value. Furthermore, we would advocate creating clear guidelines for hip fracture patients specifying cases in which femoral head histology would be warranted.

There is NO Conflict of Interest: Yes

1353 - Day case THR - 18 months experience in the NHS

G. Snowden¹, E. Dunstan¹, N. Clement²

¹Victoria Hospital Kirkcaldy, Trauma and Orthopaedics, Kirkcaldy, United Kingdom, ²University of Edinburgh/ Edinburgh Royal Infirmary, Trauma and Orthopaedics, Edinburgh, United Kingdom

Background: Since the advent of joint arthroplasty inpatient length of stays (LoS) have been steadily dropping. According to the Scottish arthroplasty project the mean inpatient LoS following a Total Hip Replacement (THR) has fallen from 10.3 days in 2001 to only 3.9 days. This reduction in patient LoS has lead units in the UK to follow the example of centres around the world and offer THR as a day case procedure. In this study we examine data gathered from the first 18 months of day case THR within a district general hospital elective orthopaedics unit.

Methods: Data was collected prospectively from all patients undergoing THR within our district general hospital elective orthopaedic unit. Patients were selected to day case THR group via consultant review at outpatient clinic and anaesthetic assessment at pre-assessment clinics. Oxford hip scores were gathered prior to surgery and again at 6 and 12 months post op. SF36 scores were collected at 6 months and 1 year post surgery.

Results: Between August 2018 and February 2020 (18 months) 40 patients successfully underwent day case THR. None of the patients discharged home where readmitted within the next 30 days. The average age of successful day case THRs was 60 years old. The at 6 months post-op mean OHS was 45.1 and at 1 year post-op the mean score was 47.2. The average improvement in OHS was 21.1 at 6 months and 26.9 at 1 year post-op. All of the patients successfully discharged as day cases where satisfied with their care and all but one would recommend it to their friends and family.

Conclusion/Implications: We have shown that day case THR is not only possible within an NHS district general hospital but gives exceptional patient outcomes with excellent patient satisfaction.

There is NO Conflict of Interest: Yes

1532 - Clinical outcomes following management of hip and knee periprosthetic joint infections in a District General Hospital

G. Kleftouris¹, A. Ng¹, S. Jones¹

¹The Mid Yorkshire Hospitals NHS Trust, Trauma and Orthopaedics, Wakefield, United Kingdom

Background: Periprosthetic joint infection (PJI) remains a challenging complication following hip and knee arthroplasty surgery. The aim of this study was to report on the outcomes of periprosthetic joint infections treated in a District General Hospital.

Methods: Between January 2015 and December 2018, all patients treated for periprosthetic joint infection in our institution were included retrospectively in the study. Periprosthetic joint infection was defined according to the criteria set by the Musculoskeletal Infection Society. The primary outcome of the study was to report on the 1-year infection free rate of this cohort. Secondary parameters included patient demographics, timing of infection since the index procedure, length of antibiotic course, operating surgeon, and the pathogen isolated.    

Results: Forty-seven patients met the inclusion criteria. The overall 1-year infection free rate was 80% (37/46 patients). Thirteen patients had debridement, antibiotics and implant retention; 8/13 (61.5%) patients were free of infection at 1 year. Six patients had single stage revision; all of them were infection-free at one year (100%). Twenty-seven patients had 2-stage revision; 23/27 (85.2%) were infection-free at 1 year. The median time of developing PJI following total hip replacement and total knee replacement was 25.3 months. Twelve of the 33 patients (36.4%) who had either a single or a 2-stage revision had low grade infection. There was no association between 1-year re-infection and operating surgeon or the isolated pathogen.

Conclusion: Periprosthetic joint infections can be treated successfully in a General District Hospital. Re-infection rates in our institution were comparable to rates reported in literature. Single stage revision can lead to excellent results; careful patient selection and a dedicated multidiscipline team are prerequisites for good clinical outcomes. Even following a two-stage approach, periprosthetic joint infections can be a challenging condition to treat.

There is NO Conflict of Interest: Yes

1565 - A comparison of acute vs inpatient hip fractures [A study conducted using data from the Scottish Hip Fracture Audit]

A.G.C. Hay-David¹, A. Stewart², R. Houson², G. Holt²

¹Queen Elizabeth University Hospital, Trauma & Orthopaedics, Glasgow, United Kingdom, ²University Hospital Crosshouse, Trauma & Orthopaedics, Crosshouse, United Kingdom

Background: This study sets out to identify if there is a difference in patient populations and outcomes for those admitted acutely (from their own home, care homes or non-NHS residences) compared to those who fracture their hip as an inpatient (in hospital, in rehabilitation or in NHS Continuing Care).

Method: Retrospective data collection from the Scottish MSK audit. Eighteen months were analysed (01/2017-06/2018) to identify patient demographics and outcomes.

Results: 10,140 patients. 92% (9320/10,140) admitted acutely: 81% (7535/9320) own homes, 19% (1755/9320) care homes, <1% (31/9320) from other non-NHS origins. Inpatients accounted for 8% (820/10,140): 70% (578/820) were on acute wards, 20% (167/820) rehab, 9% (76/820) NHS Continuing Care. No difference in ages: 80.1 years acutes vs 80.2 years inpatients, p=0.73. Gender was significant amongst inpatients: males 11% (317/3009) vs females 7% (504/7133), p<0.001. The inpatient hip fractures had longer inpatient stays than the acutely admitted hip fractures (40 vs 17 days, p<0.001) and spent a longer time in rehabilitation (32 vs 25 days, p<0.001). They were less likely to return to their own, or care, home in 30 days (23% vs 60%, p<0.001), or, at 60 days post-admission (41% vs 74%, p<0.001). Mortality rate was higher at 30 days (13% vs 6%, p<0.001) as well as at 60 days post admission (21% vs 10%, p<0.001). There was no difference in readmission rates within 14 days.

Conclusions/Findings: Inpatient hip fractures constitute a much smaller proportion compared with acute admissions yet they have significantly worse outcomes. This may be because patients with acute fractures have been admitted following the recommended standards of care. Meanwhile, inpatients have already been admitted medically unwell and may have more co-morbidities. Further work is required to identify why such a disparity in outcomes should arise and, thereby, aim to improve the care that these patients receive.

There is NO Conflict of Interest: No

Disclosure: There is no conflict of interest for the 1st author. The 4th author is Chairman of the Scottish Hip Fracture Audit and Advisory Group. The 2nd / 3rd authors are Advanced Nurse Practitioners and are members of the Group. There was no financial interest sought nor received by the authors.

1583 - Should we be prepping the foot? Stockinette use and drape contamination during hip arthroplasty

S. Abbott¹, A. Naraen¹, D. Rawaf¹, J. Craik¹

¹Epsom and St Helier University Hospitals NHS Trust, Trauma and Orthopaedics, Sutton, United Kingdom

Background:  A frequent technique of preparing the operative field during hip arthroplasty utilises a sterile stockinette over an unprepped foot. There is potential for particle contamination from the foot to the surgical site with this technique. This study aims to assess surgical site contamination when draping for hip arthroplasty without disinfecting the foot.  

Methods: UV fluorescent powder was used as a surrogate for microbial presence on the foot. Powder was applied to a volunteer’s foot to a level where antibacterial prep would stop. The leg was then draped according to three methods; directly with stockinette only, wrapping the foot without using a sticky seal followed by stockinette, and wrapping the foot with use of the sticky seal followed by stockinette. UV light was used to assess the proximal spread of powder after draping.

Results: Contamination of the sterile field was found with all methods of draping. Spread was particularly noted in the groin, posterior to the thigh and distal to mid-thigh. Wrapping the foot in a small drape without using the sticky seal prior to stockinette application was associated with significantly greater contamination when compared with use of the sticky seal (p=0.004).

Conclusion: Routine formal prepping of the foot during hip arthroplasty is recommended to reduce the risk of surgical site contamination. Surgeons who select not to prep the foot should make use of a small drape with a sticky seal prior to stockinette application and consider applying a further U drape to the hip.

There is NO Conflict of Interest: Yes

1590 - Heterotopic Ossification Following Acetabular Fracture Fixation, a Retrospective Cohort Study

T. Barker¹, F. Khatun¹, D. Gill¹, B. Davis¹

¹Norfolk and Norwich University Hospital, Trauma and Orthopaedics, Norwich, United Kingdom

Background: Heterotopic Ossification (HO) is a complication commonly seen following operative fixation of acetabular fractures. The pathological process is not fully understood, and the rates of HO show great variability depending on the study, however a meta-analysis showed the rate to be 25.6% for HO overall, and 5.7% for clinically significant HO (Brooker Grades III-IV), and it did not find a statistically significant reduction in HO in papers advocating the use of Radiotherapy or Indomethacin for prophylaxis. This case series looks at patients following acetabular fracture fixation, performed by a single surgeon at a tertiary centre in the UK. His technique involves minimal dissection of devitalised soft-tissue and minimal fixation required, with an emphasis on reducing surgical time. Neither Indomethacin or Radiotherapy are used.

Methods: This is a retrospective cohort study, of consecutive patients presenting to Norfolk and Norwich University Hospital between 2010 and 2020, and managed by a single surgeon (author BD). Follow up radiographs were assessed for the presence of HO. Patients with insufficient follow up (<10 weeks) were excluded. Other reasons for exclusion were age <18, primary surgery elsewhere, or chronic fracture at presentation.

Results: 68 patients met the inclusion criteria. The male:female ratio was 54:14, mean age was 47 (range 19-87). Kocher-Langenbeck was the primary approach in 84% of cases (n=57). Mean follow up was 381 days (range 78-2776). No patients received prophylactic radiotherapy or indomethacin. The incidence of HO was 10.3% overall, and was 2.9% for Brooker grade III-IV. HO was clinically significant in 1.5% (n=1). When comparing with the results of a 2005 meta-analysis, the reduction in total HO was clinically significant (p<0.05) however the lower rate of clinically significant HO was not.

Conclusions: We propose that the risk of HO following acetabular fracture fixation can be successfully mitigated by using the techniques outlined.

There is NO Conflict of Interest: Yes

1666 - Treatment of Acute Periprosthetic Joint Infection in Total Hip Arthroplasty: The single-stage approach

J. Robinson¹, P. Moriarty², C. Wallace², S. Konan², F. Haddad²

¹Bronx Lebanon Hospital, New York, United States, ²University College London Hospitals, Orthopaedics, London, United Kingdom

Background: Prosthetic joint infection (PJI) after total hip arthroplasty (THA) can be a difficult and costly complication to treat.  In the acute setting (6-8 weeks post-operatively) debridement and exchange of all modular components with retention of stable implants is the popular treatment option.  While this option is easier on both the patient and the surgeon it does limit the amount of debridement that can be performed.  The aim of this study is to present the outcomes and methodology of single-stage exchange to treat acute PJI in THA.

Methods: We retrospectively reviewed patients undergoing single-stage exchange for the treatment of acute PJI from 2002-2014 at our institution.  Inclusion criteria required patients to be culture positive for a deep infection after cementless primary or revision THA and have a minimum 5-year follow up.

Results: 39 patients were included in the study.  There were 21 males and 18 females with a mean age of 64years.  All patients had minimum 5-year follow-up. There were 33 primary THA’s and 6 revision THA’s. Average time from index operation to development of symptoms was 18days.  The most common organism cultured was coagulase negative Staph 25%.   35 out of 39 patients were infection free at most recent follow up with only 4 re-infections.  All re-infections resolved after two-stage revision. 

Discussion: Our study shows that single-stage exchange is a viable and successful treatment option for PJI in the acute setting. We believe that the removal of implants gives us access to perform a thorough debridement aiding in the eradication of the infection. In the acute setting cementless implants can be removed with relative ease and little to no bone loss. Our study shows 90% success rate and retention of implants at most recent follow up.

There is NO Conflict of Interest: No

Disclosure: Senior authors report board membership of the Bone and Joint Journal and the Annals of the Royal College of Surgeons; consultancy for Smith & Nephew, Corin, MatOrtho and Stryker; service on speakers’ bureaus for Smith & Nephew and Stryker; all outside the submitted work.

1725 - Should we change our follow-up of total hip arthroplasty?

M. Ammori¹, M. Haynes², M. Girgis¹, M. Lovell¹

¹Wythenshawe Hospital, Orthopaedics, Wythenshawe, United Kingdom, ²University of Manchester, Manchester Medical School, Manchester, United Kingdom

Background: A self-referral system has been proposed as a safe alternative to routine follow-up for patients undergoing primary uncemented ODEP 10A* total hip arthroplasty and there are calls for a similar study using cemented implants. Self-referral depends on the patient being symptomatic. Silent osteolysis is the major indication for revision in asymptomatic patients but is less prevalent with modern implants. The objective of this study was to establish the method of referral of patients who undergo revision after primary cemented total hip arthroplasty to determine if long-term follow-up is necessary.

Methods: Out of a single surgeon series of 1,996 primary total hip arthroplasties between September 1998 and June 2019, 23 patients underwent a subsequent revision. The primary implants included Charnley/Opera (n=9), Exeter/Opera (n=2), Exeter/Contemporary (n=9), Exeter/Trident (n=2) and Corail/Ogee (n=1). Data were retrospectively collected and included patient demographics, dates of primary and revision arthroplasty and method of referral.

Results: Five patients (21.7%) underwent a revision total hip arthroplasty within the first year and 12 (52.2%) within seven years. Seven patients (30.4%) attended Accident & Emergency, six (26.1%) were referred by General Practitioners, two (8.7%) were inpatient referrals and one (4.3%) self-referred. Seven patients (30.4%) were identified at routine follow-up [aseptic loosening (n=3), infection (n=3) and leg length discrepancy (n=1)].

Conclusions: We found long term follow-up to be unnecessary. Of those identified at follow-up, we felt they would have otherwise  presented with symptoms. Studies using a system of self-referral should be conducted to determine the safety and efficacy of this method.

There is NO Conflict of Interest: Yes

1763 - Incidental improvements to fragility fracture service with the arrival of the COVID-19 pandemic

M. O'Hare¹, G. McAlinden¹, A. Mayne¹, D. Shirley¹

¹Ulster Hospital Dundonald, Trauma & Orthopaedics, Belfast, United Kingdom

Background: We describe the changes that occurred to our fracture service during the first three months of COVID-19. Our fracture unit is within an acute hospital with approximately 400 hip fractures per annum in one theatre with three additional sessions and competes with adult and paediatric fracture services. Our elective practice is separately sited and during the pandemic ambulatory patients had surgery on the elective site; this included two THRs for fracture. In NI we do not receive payment for results and local government sets a 48 hour target to surgery. We aimed to analyse how the pandemic impacted hip fracture care.

Methods: Evaluation of a prospectively-collected Fracture Outcomes Research Database between 01/03/2020 and 31/05/2020; this was compared with data submitted to the NHFD in 2019.

Results: The number of hip fractures diagnosed remained constant with 109 hip fractures during the 3 months. Our proportion of patients getting surgery within 36 hours improved from 33.0% in 2019 to 66.5%. Our length of acute stay (LOS) reduced from 15.7 days to 10.2 days. Our 30-day mortality reduced from 6.75% to 5.5%. 7 patients in 2020 were diagnosed with COVID-19 in the peri-operative period; there were no swab positive COVID-19 deaths.

Conclusions: Ambulatory patients displaced from our primary theatre ensured faster theatre access for hip fracture patients; we doubled the number of hip fractures operated on within 36 hours. LOS reduced by a third and the 30-day mortality reduced from 6.75% to 5.5%.

Implications: The additional theatre space free for allocation to hip fractures reduces time to theatre and LOS and 30-day mortality. Future comparison with NHFD 2020 figures will identify if the local trends were observed nationally.

There is NO Conflict of Interest: Yes

1794 - Does preoperative digital templating help restore leg length discrepancy and femoral offset in patients undergoing Total Hip Arthroplasty for primary osteoarthritis

D. Parmar¹, J. Wong², M. Gibson¹, P. Subramanian¹, P. Jaiswal¹

¹Royal Free Hospital Foundation Trust, T&O, London, United Kingdom, ²Royal Free Hospital Foundation Trust, London, United Kingdom

The aim of this study was to compare the accuracy in correction of leg length discrepancy (LLD) and restoring femoral offset in patients undergoing total hip arthroplasty (THA) with preoperative digital templating versus without. Secondary objectives were the accuracy of implant sizes (templated versus actual), cup inclination and the femoral neck cut.
This retrospective cohort study compared consecutive patients who underwent THA for primary osteoarthritis. In a 12 month period 56 patients underwent arthroplasty surgery with pre-operative digital templating using Traumacad (Brainlab AG Germany) and 50 patients without templating.
The templated and non-templated cohorts were matched for variables including age (mean = 71.8 years (sd 11) vs 70.9 years sd (10.4), pre op LLD (– 4.9mm (sd 7.4) vs – 5.2mm (sd 7.9) and pre op offset (41.2 sd (6.7) vs 43.7 (sd5.9). Two independent blinded observers recorded all radiological data.
Preoperative digital templating resulted in correction of LLD to <5mm in 76.8% of cases, 5-10mm in 21.4% and >10mm in 1 case only (1.8%). The non-templated cohort had a LLD <5mm in 50% of cases, 5-10mm in 28% and >10mm in 22% (11 patients). Chi square testing demonstrated this to be statistically significant (p = 0.002).
The mean pre-operative offset in templated group was 40mm (sd 4.6) and 46mm (sd 5.1) postoperatively . The non-templated cohort had a mean pre-operative offset off 42 (sd 8.2) and 36mm (sd 6.2) post-operatively. Independent t testing revealed statistical significance at a p value of 0.05.
Preoperative digital templating leads to an increased likelihood of restoring LLD to <5mm and a significantly increased likelihood of preventing lengthening > 10mm.
Templating significantly increases the chance of restoring femoral offset to match the native hip and a negative (decreased) offset is seen in the non-templated group of patients.

There is NO Conflict of Interest: Yes

1808 - Direct contact between the acetabular component and bone reduces the ability to maintain cement pressure during the middle stages of cement curing: An in vitro study of the effects of Polymethyl Methacrylate spacers in total hip arthroplasty

S. Salih¹, A. Gordon¹, S. Salih¹

¹Northern General Hospital Sheffield, Sheffield, United Kingdom

Background: Failure of the bone-cement interface of the acetabular component is implicated in up to 8% of cemented total hip replacements at 14 years. A good cement mantle is generally accepted to mean uniform cement thickness with good penetration into trabecular bone. Acetabular components with spacers ensure that the component does not ‘bottom out’ and there is a uniform cement mantle. Their effect on cement pressure however, critical for creating good penetration of the cement into trabecular bone, has not previously been studied.

Methods: Sawbone acetabulums were prepared with pressure monitors. A ball pusher was fitted with a forcemeter. Vacuum mixed bone cement was prepared and introduced at 1m:30s, cups were introduced at 3m:30s. Data was collected until 6 minutes post mix.
Cups with spacers (‘Bobble’ group) were introduced with a target force of 60N so that the spacers contacted the sawbone. Cups without spacers were placed ‘bottomed out’ (‘bottom’ group) on the sawbone with a target force of 60N, or in an ‘ideal’ position without contacting the sawbone (‘ideal’ group).

Results: The bobble group produced mean pressures 5.25kPa (mean force 58.7N). The bottom group produced 10.5kPa (mean force 68.2N). The ‘ideal’ group produced 12.85kPa peripherally (mean force 12.7N). The Cement pressures in the ‘ideal’  group were significantly higher (P<0.001) than both other groups despite the much lower force used.

Conclusions: Contact between the cup and sawbone, either directly or via spacers, reduces the ability to maintain cement pressure. Maintaining cement pressure at a higher level than capillary blood pressure throughout cement curing may be beneficial to prevent blood ‘pushing back’ into the bone cement interface. The authors suggest cups with spacers should not be intentionally pushed against bone, but used as a safety net, and the placement of the cup should be based on intra-operative landmarks.

There is NO Conflict of Interest: No

Disclosure: Acknowledgements, Declarations, and disclosures: Thanks to JRI for providing saw bones and acetabular components (Avanteon), Ivan Green from Fruition designs for providing the pressure sensors and transducers, Rebecca Malton and Jacklyn Ellis (Stryker) for providing acetabular components (Rimfit) and Ian Duffy (Hereaus) for providing cement (Palacos) and mixing equipment.

1837 - Management of greater trochanteric pain syndrome: a systematic review of randomised controlled trials

E.L. Goh^1,2, S. Chidambaram², J. Lambert³

¹University of Oxford, Oxford Trauma, Oxford, United Kingdom, ²University of Oxford, Oxford University Clinical Academic Graduate School, Oxford, United Kingdom, ³University of Oxford, Oxford, United Kingdom

Background: Greater trochanteric pain syndrome (GTPS) is a condition characterised by gluteus medius and/or minimus tendinopathy, with or without co-existing bursal pathology. A wide range of treatment modalities have been implicated yet there remains a paucity of high quality evidence for the treatment of this condition. The present systematic review aims to evaluate the evidence for the management of GTPS.

Methods: Medline, Embase, Scopus and Cochrane Central Register of Controlled Trials (CENTRAL) were searched from the date of inception to 23rd December 2019. Randomised controlled trials (RCTs) evaluating treatment for GTPS in individuals aged 16 years and older, with no previous surgical procedures of the hip joint, and history of inflammatory joint disease. Non-English, non-human, and unpublished studies were excluded.

Results: A total of 13 RCTs enrolling 864 patients to treatment arms including education, physiotherapy/exercise therapy, corticosteroid injections, platelet-rich plasma (PRP) injections, hyaluronic acid injections, and shockwave therapy were included. There is moderate quality evidence supporting the role of combined education and physiotherapy, and the limited benefit of corticosteroids in the management of GTPS. Limited evidence is available regarding the effects of alternative treatments including PRP injections, hyaluronic acid injections, and shockwave therapy in treating this condition.

Conclusions: There is an increasing number of high quality research into the treatment of GTPS. However, there is a lack of high quality evidence supporting the use of PRP injections, hyaluronic acid injections, and shockwave therapy as part of the treatment algorithm. Combination therapy with education and physiotherapy should be the mainstay of treatment, with no role for corticosteroids injections.

There is NO Conflict of Interest: Yes

1843 - Changing Trends implant usage in Total Hip Replacement

A. Bashir¹, N. Nibhani¹, K. Gunasekaran¹

¹Royal Liverpool University Hospital, Orthopaedics, Liverpool, United Kingdom

Background: There is continued debate as to whether cemented or un-cemented implants should be used in primary Total Hip Replacement (THR).The Getting It Right First Time (GIRFT) publication in 2015 and NHS England consultation document 2019/20 highlighted areas of excellence and areas for focus and improvement.

Aim: Purpose of this study was to identify trends in implants used in primary THR.

Methods: During the period 2013-2018, we identified patients who underwent primary THR in our unit. Data collected included type of implants (cemented or uncemented) and their Orthopaedic Data Evaluation Panel (ODEP) rating. Regression analysis of annual trend of implant type, volume and ODEP ratings of THR was undertaken.

Results: Data of 1753 THR were analysed from 2013 to 2018. Of these 583(33%) were un-cemented, 568 (32%) were cemented, 275(15%) were hybrid and 327(18%) reverse hybrid. Uncemented THR declined from 60% in 2013 to 24% in 2018 (p<0.05%). Cemented THRs increased from 11% to 57% (p<0.05) while hybrid and reverse hybrid did not show a significant trend. Annual volumes of THR also showed a gradual downward trend from 343 in 2013 to 256 in 2018 (p<0.05). Implants with ODEP rating of >10A were used as follows: 97% of cemented and 99% of un-cemented cups, 99% of cemented and 94% of un-cemented femoral stems. There was no significant change in ODEP ratings of implants during the study period.

Conclusion: There was a significant shift to cemented THRs over the study period. This was associated with a reduction in volumes of THRs performed. Further detailed analysis is required to identify any causality in this association.
There was no overall significant change in ODEP ratings of implants used.

1850 - Long-term follow up of porous tantalum uncemented acetabular components in complex revision hip arthroplasty

M. Ibrahim¹, L. Rahman¹, L. Somerville¹, J. Howard¹, D. Naudie¹, S. MacDonald¹, R. McCalden¹

¹London Health Sciences Centre - University Hospital - Western University, Adult Lower Limb Arthroplasty, London, Canada

Introduction: The use of Porous Tantalum cementless component in complex revision total hip arthroplasty (THA) has gained popularity in the last 2 decades with small number of studies reporting on long-term outcomes. The aim of this study is to analyse long-term clinical outcomes, radiological appearance and survivorship of this implant.

Methods: We reviewed our database for patients with tantalum cementless acetabular component with a minimum 7 years follow-up. This study was approved by our research ethics board. We reviewed the Patients’ PROMS including SF12 and WOMAC. We reviewed their latest radiographs to look for any evidence of loosening. We analysed the data using SPSS Statistics and survivorship using Kaplan-Meier survival analysis with revision as an end point.

Results: 101 patients (102 hips) had revision THA between 2003 and 2009 using porous tantalum cup. 26 patients (27 hips) died before the 7 years follow up for reasons unrelated to their surgery and 10 patients lost to FU, this leaves 65 patients with mean FU of 10.1 (7-15.7). Ten-year Survival analysis revealed 95.3% (95%CI 90.1 to 100.0). The total WOMAC scores were improved significantly from 48.9 ± 19.2 preoperatively to 67.5 ± 22.6 postoperatively (p value < 0.001). The SF 12 physical component (PCS) was improved significantly (P = 0.008) with 29.3 ±7.3 preoperatively to 33.4 ± 9 postoperatively. Radiological analysis revealed well-fixed implants with no loosening or migration. There were few complications in this cohort. 5 patients had DAIR with no revision required, 2 patients with periprosthetic femoral fractures required revision of the stem only and one with dislocation that didn’t require cup revision.

Conclusion: At seven to fifteen-year follow up, a porous tantalum cup has shown a stable fixation with improved PROMS and survivorship of 95.3%. This indicates that this acetabular component remains a great option for complex revision THA.

There is NO Conflict of Interest: No

Disclosure: Dr Howard, Naudie, McCalden and MacDonald are paid consultants for Smith and Nephew (S&N), DePuy and Stryker and they receive institutional support from S&N, Stryker and Depuy. The rest of the Coauthors have nothing to declare. The presenting author (Mazin Ibrahim) Has nothing to declare.

1873 - Comparison of the Incidence of pulmonary embolism after total hip replacement among trauma and elective patients. Retrospective analysis of a single centre eight years experience

E. Bagouri¹, J.C. Cruickshank¹, A. Daoub¹, A. Wignal¹, M. Kumar¹, A. Mohsen¹

¹Hull University Teaching Hospitals NHS Trust, Trauma and Orthopaedics, Hull, United Kingdom

Introduction: Venous thrombo-thromboembolism remains a major concern after total hip arthroplasty (THR) & pulmonary embolism (PE) can be life-threatening; CT pulmonary angiogram (CTPA) remains the golden standard in diagnosing PE.
In this study, we are comparing the indications outcomes of CTPA & the incidence of PE among trauma & elective THR patients.

Methodology: Prospective analysis of retrospectively collected data from a single trauma center electronic database, coding department records, and National hip fracture database.
The data included the patients’ demographics, indications, and outcomes of CTPAs &chest X-rays-, admission, and discharge dates. Furthermore, the mortality within 120 days and causes of death among patients who had CTPAs were collected.

Results: Between 2010 and 2018 there were 7858 patients who had a lower limb arthroplasty, 3965 were THR including 3700 elective THR, and 265 trauma. The mean age for the patients was 72 and 76 for elective &trauma THR respectively. 64 CTPAs were requested for the elective THR group Vs 13 for the trauma THRs. 15 of the elective group CTPAs had PEs (23%) compared to 5 (38.5%) among trauma patients (overall rate PE of 0.41% for THR). There was no mortality among patients with PE identified on CTPA. Shortness of breath (SB) and low saturations were the commonest indications for CTPA among both groups. SB occurred in 10 of 13 (77%) trauma cases and 4 of the 5 (80%) positive for PE. While in the 64 elective patients 45 (70%) had SB, of those 10 of the 15 (67%) who were positive for PE.

Results: Patients who underwent THR for trauma in our sample had a higher incidence of PEs. That can be due to the different protocols of chemical prophylaxis or the added physiological stresses associated with trauma. That should be considered when consenting patients and in their post-operative management.

There is NO Conflict of Interest: Yes

1878 - Elective Total Hip Arthroplasty in patients with neurodegenerative disorders and epilepsy: A report of 2,860 cases from the Swedish Hip Arthroplasty Register

A. Bhattacharjee¹, A. Wojtowicz², J. Nåtman², E. Bülow², O. Rolfson², P. Cnudde^1,2

¹Prince Phillip Hospital, Wales Deanery, Cardiff, United Kingdom, ²Swedish Arthroplasty Registry, Sweden, Sweden

Introduction: Few studies report the outcome of total hip arthroplasty (THA) with neurodegenerative disorders and epilepsy. This longitudinal study reports mortality, adverse events, dislocation, reoperation, revision and patient-reported outcomes (PROMs) in this cohort from the Swedish Hip Arthroplasty Register (SHAR).

Methods: The SHAR and the linked national patient register used to identify elective THA patients with the pre-existing neurodegenerative and epileptiform disorder from 2005-2014. Patients matched on demographics, Charlson comorbidity index, diagnosis, surgical approach, head size and bearing. PROMs, Health-Related Quality of Life (HRQoL) and adverse events ( 30 & 90 days), dislocation at one year, reoperation, revision (exchange or removal of components) and mortality reported. Patients were followed-up until death or end of the study. P- values < 0.05 considered significant.

Results: Study period had 132,349 elective THA’s - 2,860 patients had neurodegenerative or epileptiform disorder. Broad categories were dementia (37.6%), epilepsy (35.3%), Parkinson’s and Parkinson’s like diseases,(18.8%) and others (8.3%).
These patients had significantly higher mortality, dislocation rate, reoperation rate and revision rate (p <.0.05).
More patients encountered adverse events at both 30 & 90-days in comparison to the matched cohort (15.6% versus 11.9% and 18.9% versus 14.4% respectively). Despite a lower starting level, there was no difference in EQ-5D-3L at one year in the study group. In total, 83.8% of the patients were satisfied with outcome, and 89.7% of patients reported reduction in pain after surgery.

Conclusion: While few patients report being satisfied or very satisfied with the outcome of the surgery, there is no difference in improvement in the HRQoL between the study and the matched cohort. However, these patients have higher postoperative adverse events. Nevertheless, the change in HRQoL and patient satisfaction in this group indicate the requirement for developing surgical strategies to reduce the risk of dislocation, reoperation and revision.

There is NO Conflict of Interest: No

1884 - A comparison of the outcomes of short versus long cephalomedullary nail fixation over a 10 year period

K. Cheema¹, E. Cornish¹, M. Chawda¹

¹Ysbyty Gwynedd, Bangor, Trauma & Orthopaedics, Bangor, United Kingdom

Background: The choice of short versus long cephalomedullary nail (CMN) fixation is one that is frequently discussed at trauma meetings. The aim of this retrospective study was to analyse the outcomes of these procedures, performed at our unit over the last 10 years.

Method: Data was retrospectively collected using the National Hip Fracture Database records at our unit pertaining to all patients who had received a short or long CMN between 01/01/2010-31/12/2019.

Results: 262 patients received long CMNs whilst 42 received short CMNs over this period. Of these patients, there were 4 implant failures (4/42 = 9.5%) amongst the short nails and 8 amongst the long nails (8/262 = 3%, p=0.03). The most common reason for failure was femoral head collapse causing eventual protrusion of the tip of the blade (3 for long nails and 2 for short nails, p=0.07). Cut out was more frequent in long nails (2 versus 1 for short nails, p=0.34). In two of these three cases the tip-apex distance was less than 25mm (12mm and 23mm) however in 1 case it was 39mm. There were 2 periprosthetic fractures, one in each group at the distal aspect of the nail (p=0.14). 2 patients in the long nail group required re-operation for distal migration of the nail.

Conclusion: This study identified a significantly higher rate of implant failures amongst short nails compared to long nails, in our unit over the last 10 years. However, the rate of periprosthetic fractures was comparable amongst both groups.

There is NO Conflict of Interest: Yes

74 - BUILDING AN INTERNAL SOFT TISSUE KNEE REGISTRY – FROM A GOOD IDEA TO THE CURRENT REALITY

M McMullan¹

¹Northumbria NHS Foundation Trust, Newcastle, United Kingdom

Background: Recent publications in the media have shone a negative light on knee arthroscopy. Despite this it is still a procedure that can benefit patients greatly when clinically appropriate. In Northumbria, we set out to create an internal soft tissue knee registry with the aim of collecting data, analysing outcomes and providing evidence for continuing to perform knee arthroscopies in suitable patients.

Methods: Set up in 2017, all patients undergoing an arthroscopic knee operation, not including ligament reconstructions, were submitted to the registry. Along with clinical and imaging information, KOOS and EQ-5D scores were collected pre-operatively, then at 6 months and 12 months post-operatively. All consultants performing elective knee arthroscopies were required to submit data.

Results: 800 patients are registered currently, 65% of these being male with a mean age of 48. All have pre-op PROMS whilst currently 42% have scores at all stages collected. Eleven consultants contributed to the registry with only three consultants making up 74% of the patients. Four consultants performed less than 10 arthroscopies during this time frame.
A clinically significant change was seen in average pre and post op KOOS scores at one year (229.04 to 328.02). Average EQ-5D index improved by 0.11 at one year yet the EQ-5D VAS showed no change.

Conclusions: Data from an internal registry is a powerful tool and going forward our registry can be used to evidence that we are giving correct patients the correct treatment and furthermore provide commissioners with this information. We were able to set this up with minimal resources and are keen to share its benefit with others.

There is NO Conflict of Interest: Yes

317 - Pain and Function in Cemented and Cementless Unicompartmental Knee Replacements: A 5-year Comparative Study

A. Rahman¹, C. Jenkins², A. Price², W. Jackson², C. Dodd², S. Mellon¹, K. Barker², D. Murray^1,2

¹Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, Oxford, United Kingdom, ²Nuffield Orthopaedic Centre, Oxford, United Kingdom

Introduction: Unicompartmental Knee Replacements (UKRs) offer improved outcomes and reduced healthcare costs compared to Total Knee Replacements. However, UKRs have higher revision rates, primarily due implant loosening. Cementless UKRs have been shown to reduce the risk of such loosening compared to cemented variants. However, the overall mid-to-long-term clinical benefits of cementless UKRs remain unclear.

Objectives: To compare pain-related and function-related outcomes of cementless and cemented medial UKR at 5 years after surgery.

Methods: 262 cemented and 262 cementless UKR were implanted by 4 high-volume surgeons, and assessed at 5 years postoperatively by independent physiotherapists. Implants, instrumentation used, and pre/peri/post-operative management were identical, with the exception of method of fixation. The assessment included Oxford Knee Score (OKS), American Knee Society Score (AKSS), Charnley Grade, EQ-5D-5L and two pain scores, the Intermittent and Constant Osteoarthritis Pain (ICOAP) and PainDetect (PD) scores.

Results: There were no significant differences in pre-operative characteristics and postoperative revision, reoperation, and complication rates (0.8%, 2.2%, 4% respectively).

Patients with the cementless UKR had significantly better pain-related scores with OKS, AKSS, and EQ-5D, and the differences were proportionally much greater than differences in the overall scores. 45% more cementless UKR patients experienced no pain at all (ICOAP=0/100, 61%v43%, p<0.0001), and 75% less experienced ≥moderate pain (ICOAP>40/100, 1.6%v6.6%, p=0.0433). No cementless patients experienced severe/extreme pain (ICOAP>60/100); 2.9% of cemented patients did.

97% of all patients who experienced constant pain also experienced intermittent pain. When split into 2 pain groups, the high-pain group (ICOAP 21-100v0-20) were more likely to have out-of-knee pathology (Charnley-C OR 1.37-1.48) and neuropathic pain (PD-Q OR 3.14-6.29).

Conclusion: Cementless UKR is associated with better patient reported outcomes than cemented. The biggest difference was in pain, which may explain differences in function and general health. We do not understand why this is, and further study is necessary.

There is NO Conflict of Interest: No

Disclosure: Some authors have received personal fees for consultancy for Zimmer Biomet, Johnson and Johnson, and Medacta, outside the submitted work. Some authors have various patents related to knee replacement with royalties paid.

406 - A prospective randomised controlled trial comparing biochemical, thermal, and macroscopic soft tissue injury outcomes in conventional jig-based versus robotic total knee arthroplasty

B Kayani¹, J Tahmassebi¹, A Ayuob¹, S Oussedik¹, S Konan¹, FS Haddad¹

¹University College London Hospital, London, United Kingdom

Introduction: The objectives of this study were to compare the serum inflammatory reaction, localised thermal response and macroscopic soft tissue injury outcomes in conventional jig-based total knee arthroplasty (conventional TKA) versus robotic total knee arthroplasty (robotic TKA).

Methods: This prospective randomised single-blinded controlled trial included 15 patients undergoing conventional TKA versus 15 patients receiving robotic TKA. Predefined serum markers of inflammation and topical knee temperature were collected preoperatively and postoperatively at 6 hours, day 1, day 2, day 7, and day 28 following TKA. Blinded observers used the Macroscopic Soft Tissue Injury (MASTI) classification system to grade intraoperative periarticular soft tissue injury and bone trauma. Plain radiographs were used to assess the accuracy of achieving the planned limb alignment and implant positioning in both treatment groups.

Results: Conventional TKA and robotic TKA had comparable increases in the postoperative serum inflammatory cytokines and localised thermal responses at 6 hours, day 1, day 2 and day 28 after surgery. Robotic TKA had reduced levels of interleukin-6 (p<0.001),tumour necrosis factor-alpha (p=0.021), erythrocyte sedimentation rate (p=0.001), C-reactive protein (p=0.004), and creatine kinase (p=0.004) at day 7 after surgery compared to conventional TKA. Robotic TKA was associated with improved intraoperative preservation of the periarticular soft tissue envelope (p<0.001) and reduced bone trauma (p=0.015) compared to conventional TKA. Robotic TKA improved accuracy of achieving the planned limb alignment (p<0.001), femoral component positioning (<0.001), and tibial component positioning (<0.001) compared to conventional TKA.

Conclusion: Robotic TKA was associated with a transient reduction in the early (day 7) postoperative inflammatory response but there was no difference in the immediate (<48 hours) or late (day 28) postoperative serum inflammatory responses compared to conventional TKA. Robotic TKA was associated with decreased iatrogenic periarticular soft tissue injury, reduced bone trauma and improved accuracy of implant positioning compared to conventional TKA.

There is NO Conflict of Interest: No

509 - Return to work following total knee and hip arthroplasty: the effect of patient intent and preoperative work status

K Al-Hourani¹, D MacDonald¹, G Turnbull¹, S Breusch¹, C Scott¹

¹Royal Infirmary of Edinburgh, Trauma & Orthopaedics, Edinburgh, United Kingdom

Introduction: The ability of total knee and hip arthroplasty (TKA/THA) to facilitate return to work (RTW) when it is the patient’s preoperative intent to do so remains unclear. We aimed to determine whether TKA/THA facilitated RTW in patients of working age who intended to return. 

Materials and Methods: Prospective cohort study of 173 consecutive patients <65 years of age, undergoing unilateral  TKA (n=82: median age 58, range 39-65; 36 (43.9%) male) or THA (n=91: median age 59 , range 34-65; 42 (46.2%) male) during 2018. Oxford knee/hip scores (OKS/OHS), Oxford-APQ and EuroQol-5 dimension (EQ-5D) scores were measured preoperatively and at one year when an employment questionnaire was also completed. 

Results: Of patients who intended to RTW, 44/52 (84.6%) RTW by one year following TKA (at mean 14.8±8.4 weeks) and 53/60 (88.3%) following THA (at mean 13.6±7.5 weeks). Failure to RTW despite intent was associated with job physicality for TKA (p=0.004) and negative preoperative EQ-5D for THA (p=0.01). In patients unable to work prior to surgery due to joint disease, fewer RTW:  4/21 (19.0%) after TKA; and 6/17 (35.3%) after THA. Preoperative OKS >18.5 predicted RTW with 74% sensitivity (p<0.001); preoperative OHS >19.5 predicted RTW with 75% sensitivity (p<0.001). Preoperative EQ-5D indices were similarly predictive (p<0.001) 

Conclusion: Where patients intend to RTW following TKA/THA, 85% RTW following TKA and 88% following THA. Patients of working age should not be left to the point where they are unable to work due to joint symptoms, as RTW becomes the exception not the rule.

There is NO Conflict of Interest: Yes

823 - 3D CT MODELLED ANALYSES OF PATELLAR RESURFACING TECHNIQUES AND THEIR INFLUENCE ON CLINICAL OUTCOMES AFTER TOTAL KNEE ARTHROPLASTY

V. Kandhari¹, S. Grasso¹, D. Myat¹, J. Twiggs², B. Fritsch¹, D. Parker,¹

¹Sydney Orthopaedic Research Institute, Orthopaedic Knee surgery, Chatswood, Australia, ²360 Knee Systems, Research, Sydney, Australia

Objective: To assess the patellar resurfacing techniques in total knee arthroplasty (TKA) using CT
scan and 3D modelling and evaluate their influence on clinical outcomes.
Methods: This retrospective study included all TKAs between 2013 and 2018. All patients underwent
preoperative and postoperative CT scans. Patellae with significant anatomical distortion secondary
to advanced arthritis were excluded. Accurately landmarked 3D models of patellae were created
from CT data in ScanIP software. Patellar resection plane tilts, button positioning and volumetric
articular restoration were evaluated using Solidworks design software. Correlation analyses were
performed between measured variables and 1-year follow-up KOOS scores.
Results: 229 of 291 TKAs satisfied the inclusion criteria. Clinical follow-up data was available for 158
TKAs. Wide variations were observed in the patellar resection plane tilts to supero-inferior and
medio-lateral patellar axes and in patellar button positioning. Resection plane was tilted laterally
and inferiorly and patellar button positioned posteriorly, inferiorly and laterally in more number of
patellae. Though total post-op patellar volume was comparable to pre-op, polyethylene volume
build-up was found in the superior-third zone. Superior tilting of resection plane [R (-0.6)] and
polyethylene volume build-up in medial part of superior-third zone [R (-0.4)] negatively correlated
with 1-year KOOS sub-scores. Superiorization of patellar button had significant positive correlation
with volume of polyethylene in superior-third zone (R-0.36).
Conclusions: There is a need to devise better and reproducible patellar resurfacing techniques to
achieve more consistent optimal patellar resection planes. Superior tilting of patellar resection plane
and supero-medial positioning of the patellar button should be avoided.

Disclosure: Vikram Kandhari, Samuel Grasso, Darli Myat - None
Joshua Twiggs - employee 360 Knee Systems.
Brett Fritsch, David Parker - Share holder 360 Knee System, Trium and Optimised ortho; Consulting work 360 Knee Systems, Global Orthopaedics, Omni; Institutional support Zimmer, Smith and Nephew, Global Orthopaedics and Arthrex.

1011 - Regional Five-year clinical outcomes of 289 cementless Oxford unicompartmental knee replacements at a non-inventor centre

H. Rajgor¹, R. Nandra¹, C. Winkworth¹, N. Aslam¹

¹Worcestershire Acute Hospitals NHS Trust, Birmingham, United Kingdom

Uncemented unicompartmental knee replacement offers a minimally invasive approach, faster rehabilitation and good levels of function, supported by evidence reporting low intra-operative fracture rate and mid-term stability with no implant migration at 5-years. Our aim was to examine the clinical outcomes in 289 consecutive Oxford unicompartmental knee arthroplasties (257 patients), five years post-operatively. Performing a retrospective study of patients treated between 2008 and 2014 in a non-inventor centre by a single surgeon. Patients with anteromedial bone on bone unicompartmental arthritis included. Oxford Knee Scores (OKSs) at last follow-up were recorded, intra-operative complications reported with commentary on revision cases. 
Mean age of patients 66 years (SD 9.6, 45 to 88 years). 122 female patients (42%) predominantly ASA 1 (36%), ASA 2 (62%) and ASA 3 (01%). There were no intra-operative complications, particularly tibia fractures during impaction. The average oxford knee score was 40.1 (n=232, Range 06 to 48, SD 8.46) at an average 6 years and 3 months from surgery, including revised patients. Six patients had their prosthesis revised within five years of the index surgery. Five-year cumulative implant survival rate was 97.8% (95% CI 97.62 to 97.98, SE 0.09). Indication for revision were: lateral side wear (n=1); dislocated spacer (n=4); instability and spacer subluxation (n=1). Thirteen patients died within five years of surgery Five-year cumulative survival rate was 94.9% (95% CI 94.87 to 94.925, SE 0.013).
Conclusion: The proportion of patients requiring revision at five years is lower than that generally reported for UKA. These findings add support for the use of the cementless OUKA outside the design centre.

There is NO Conflict of Interest: Yes

1075 - Failures and Complications with MPFL reconstruction: Our experience in 215 patients

P. Setia¹, S. Dalal¹, A. Debnath¹, R. Kotwal¹, A. Chandratreya¹

¹Princess of Wales Hospital, Trauma and Orthopaedics, Bridgend, United Kingdom

Background: Chronic lateral patellar instability is one of the most commonly seen clinical conditions encountered by knee surgeons.Medial patellofemoral ligament (MPFL) reconstruction has become increasingly popular over the last three decades. Upto 26% complication rates have been reported in literature with MPFL reconstruction.The purpose of this study is to analyse failure rates,complications of surgery for PF instability and to identify the predictive factors for failure.

Methods: A retrospective analysis of prospectively collected data was performed for all 215 (234 knees) patients who had undergone MPFL reconstruction between October 2007 and August  2018. All the cases with any postoperative complications or failures were included. A failure was defined by a postoperative patellar dislocation or surgical revision for recurrent patellar instability or anterior knee pain not resolving with conservative methods. Other complications such as stiffness,infection,neurological deficit and deep vein thrombosis were also included. Lysholm, Kujala, Tegner and radiographic features, such as trochlear dysplasia according to Dejour classification,patellar height with the Caton-Deschamps index (CDI), tibial tubercle-trochlear groove distance were analysed pre and post operatively.

Results: Six patients (2.56%) had a revision of their MPFL reconstruction, six patients (2.56%) had removal of their metal work while only three patients (1.28%) had stiffness postoperatively and required manipulation under anesthesia.Five patients (2.17%)had patellofemoral replacement over time while four patients(1.70%) had arthroscopic debridement for cartilage related pathology. There was also one case each of femoral nerve palsy, post operative infection, deep vein thrombosis, nonunion of tibial tuberosity osteotomy.

Conclusions: To our knowledge, this is the only study recording the failures and complications of MPFL reconstruction on a large patient database. Age above 30,obesity, cartilage lesions, hyperlaxity and female gender are predictors of a poor subjective outcome. Identifying the potential risk factors preoperatively can prevent future complications.

There is NO Conflict of Interest: Yes

1209 - Long-Term Results of Revision Total Knee Arthroplasty Using a Rotating Hinge Implant

W. Wignadasan¹, J. Chang¹, B. Kayani², C. Kontoghiorghe², F.S. Haddad¹

¹University College London Hospital, Trauma and Orthopaedics, London, United Kingdom, ²University College London Hospital, London, United Kingdom

Background: Rotating hinge implants are commonly used in revision total knee arthroplasty (TKA) in the setting of significant ligamentous instability or bone deficiency. These highly constrained implants have been associated with variable clinical outcomes and uncertain long-term survivorship. The aim of this study is to establish long-term functional outcomes, radiographic results, and survivorship after revision TKA with a rotating hinge implant.

Method: 41 consecutive patients undergoing revision TKA with rotating hinge components were included in the study. Indications for revision TKA included: aseptic loosening with bone and soft tissue loss in 23 cases (56.1%), fractures in 4 cases (9.8%), infection in 10 cases (24.2%), ligamentous instability in 3 cases (7.3%), and pain and malalignment in 3 cases (7.3%). Clinical outcomes recorded included the Oxford Knee Score (OKS) preoperatively and postoperatively at latest follow-up. Range of motion, implant survivorship, and complications were recorded. Mean time from date of revision TKA to last follow-up was 14 years (range, 10.7 years to 17.1. years).

Results: There was a significant improvement in OKS after revision TKA with a rotating hinge implant compared to preoperative scores (40.7 ± 4.2 vs. 21.4 ± 4.9 respectively, p<0.001). At latest follow-up, mean range of motion was 111.5° ± 9.3° and mean overall limb alignment of 0.2° ± 2.0° varus. Implant survivorship at minimum 10-year follow-up was 90.2%. Radiographic lucent lines were observed in 14 patients (34.1%); however only two of these patients (4.9%) required further revision TKA. A further two patients (4.9%) underwent revision TKA for periprosthetic fracture.

Conclusion: Revision TKA with a rotating hinge implant leads to satisfactory clinical outcomes and very good implant survivorship at long-term follow-up. Despite the relatively high complication rates where did the high complication rate come from, surgeons should have a low threshold to use these versatile implants in complex revision knee arthroplasty.

There is NO Conflict of Interest: Yes

1236 - ARE LOWER-LIMB ALIGNMENT VALUES ON CT SCANOGRAMS COMPARABLE WITH WEIGHTBEARING LONG LEG RADIOGRAPHS IN PRE- AND POST-OPERATIVE PATIENTS UNDERGOING TOTAL KNEE REPLACEMENT?

D.S. Rye^1,2, R. Walker², A. Yoong^1,2, H.B. Waterson^2,1, J.R. Phillips², A.D. Toms²

¹University of Exeter Medical School, Exeter, United Kingdom, ²Royal Devon and Exeter Hospital: Princess Elizabeth Orthopaedic Centre, Exeter Knee Reconstruction Unit, Exeter, United Kingdom

Background: Lower limb mechanical axis has long been seen as a key to successful in lower limb surgery, including knee arthroplasty. Traditionally, coronal alignment has been assessed with weight-bearing lower limb radiographs (LLR) allowing assessment of hip-knee-ankle alignment. More recently CT scanograms (CTS) have been advocated as a possible alternative, having the potential benefits of being quicker, cheaper, requiring less specialist equipment and being non-weightbearing.

Objectives: To evaluate the accuracy and comparability of lower limb alignment values derived from LLR versus CTS.

Methods: We prospectively investigated patients undergoing knee arthroplasty with preoperative and postoperative LLR and CTS, analysing both preoperative and postoperative LLRs & CTS giving 140 imaging tests for direct comparison. We used two independent observers to calculate on each of imaging modalities, on both pre- and post-operative images, the: hip-knee-ankle alignment (HKA), lateral distal femoral angle (LDFA) and medial proximal tibial angle (MPTA).

Results: 840 data points were captured from pre- and post-operative LLRs and CTSs. Analysis demonstrated very strong correlation in pre-operative HKA (LLR vs CTS, r = 0.917), post-operative HKAs (LLR vs CTS, r = 0.850) and postoperative LDFAs (LLR vs CTS, r = 0.850). Strong correlation was observed in pre-operative LDFAs (r = 0.732), MPTAs (r = 0.604), and post-operative MPTAs (r = 0.690).

Conclusion: Both pre- and post-operative LLR and CTS imaging display very strong correlation for HKA coronal alignment correlation, with strong correlation for other associated angles around the knee. Our results demonstrate that both LLR and CTS can be used interchangeably with similar results.

There is NO Conflict of Interest: Yes

1379 - Staged or Simultaneous Bilateral Total Knee Arthroplasty; When is the most clinically effective time interval to operate on your patients’ undergoing Bilateral Total Knee Replacement?

S. Radha¹, I. Afzal¹, D. Kader¹, R. Field¹

¹SWLEOC, London, United Kingdom

The question, which remains unanswered, is should bilateral Total Knee Replacements (TKRs), be performed simultaneously or staged. If staged, what should the time interval be? To date, there is no peer reviewed evidence in the orthopaedic literature investigating whether the improvement in patient satisfaction and Patient Reported Outcome Scores (PROMs) is influenced by the duration of the interval between first and second TKR when different surgical strategies are used.
We conducted a prospective, multi-surgeon, study on 1308 patients (2616 TKRs) who underwent bilateral TKRs between 2004 and 2015. The aim of this study was to identify whether there was any significant difference in patient satisfaction and PROMs improvement when performing bilateral TKRs. In this study, we used the 12-question validated Oxford Knee Score (OKS) and a visual analogue Patient Outcome Satisfaction score (0:Bad outcome – 100:Great outcome). PROMs were collected pre-operatively, one- year post-operatively and two-year post operatively.  Timing interval between first and second TKR were divided as: Zero (simultaneous), day 1 to 3 months, 3-6, 6-9, 9-12, 12-15, 15-18, 18-21, 21-24 months and > 24 months.
Results from this study showed the greatest change in both knees for the OKS was those patients who had their TKRs day 1-3 months apart. This result was also statistically significant with a p-value of 0.001. The lowest OKS change was those patient who their knee operated on >24 months apart. Patient satisfaction also correlated with these results. Those patients operated on with day 1-3 months had the highest satisfaction of 93.12 and those patients operated on >24 months had the lowest satisfaction of 91.65.
Awareness of the reported outcomes following TKR can be a useful tool for surgeons when suggesting when undertake a bilateral TKR.

There is NO Conflict of Interest: Yes

1423 - An MRI analysis of 500 patients to assess variations in popliteal artery anatomy as predictors for significant intra-operative vascular complications during knee surgery

N. Vetharajan¹, A. Dodds¹, G. Silk¹

¹Gloucestershire Hospitals NHS Foundation Trust, Trauma and Orthopaedics department, Cheltenham General Hospital, Cheltenham, United Kingdom

Background: Although vascular complications associated with knee surgery are rare, with a reported incidence of 0.03-0.12%, they can cause significant morbidity. Variations in the anatomy of the popliteal artery may mean structures are at risk during high tibial osteotomy or arthroplasty surgery.
 
Aims: The aim of this study was to quantify the proportion of patients with an aberrant popliteal artery, and to describe the variation in location of this aberrant vessels in relation to the posterior cortex of the tibia.
 
Materials and methods: In our study three independent observers (two orthopaedic surgeons and MSK radiologist) performed an analysis of 500 consecutive MRI scans (with axial, coronal and sagittal sequences) of knees who had not had prior surgery.
 
Results: 7% (35 patients) were confirmed to have an aberrant high popliteal artery variant. Of these 23 patients show a high separate anterior tibial artery variant that is present anterior to the popliteus muscle adjacent to the posterior tibial cortex. These are found to be largely in the midline posteriorly, at risk of vascular injury during osteotomy or tibial preparation during arthroplasty surgery.The remaining 12 patients had an aberrant artery variation separately with smaller-calibre vessels also anterior to the popliteus muscle which may increase the risk of intra-operative injury.
 
Conclusion: This study aims to highlight a variation in arterial anatomy that was readily identifiable on MRI knee scans. These variations should be identified during pre-operative surgical planning.

There is NO Conflict of Interest: Yes

1718 - Combined Supracondylar Nailing And Lateral Femoral Locking Plate In Complex Distal Femur Fractures: A New Technique And Outcome

K. Natarajan¹, M. Bari¹, R. Swaminathan¹

¹Tameside and Glossop Integrated Care NHS Foundation Trust, Trauma and Orthopedics, Ashton-under-Lyne, United Kingdom

Background: Complex fractures of distal femur are a challenge to treat. The fracture morphology, quality of bone and the size of the distal fragment plays a role in the choice of treatment options. Mechanical studies have shown better axial, torsional loading properties with higher load to failure with the combined nailing and plating of distal femur. We believe that this is the first report of the use of combination of the methods in treating these complex distal femoral fractures.

Objectives: To review the outcomes of combined supracondylar nailing and anatomical lateral femoral locking plate in complex distal femur fractures.

Study Design & Methods: All patients with complex distal femur fractures who underwent combined supracondylar nailing and lateral femoral locking plate fixation were included in this retrospective study. The electronic records and imaging from database were analysed.

Results: A total of 11 patients were identified from the records. 100 % of patients showed evidence of clinical and radiological union at a mean follow up of 3.8 months (range 3 to 5 months). One patient developed infection which needed removal of metal work and subsequently underwent total knee replacement for symptomatic osteoarthritis of knee. Another patient developed a bursitis over the locking plate and the plate had to be removed.

Conclusions: This new technique uses the intramedullary nail to achieve gross reduction of the distal femoral fracture with lateral locking plate, fine tuning the reduction in mediolateral/anteroposterior plane. The use of blocking screw/ pushing screw through the plate achieves anatomical reduction with correction of translation, minor valgus, varus, procurvatum and recurvatum malalignment. We believe that this technique provides stability for immediate weight bearing with higher potential for healing especially in those with osteoporotic distal femoral fractures. The results show maintenance of alignment with 100% of fractures healed.

There is NO Conflict of Interest: Yes

1911 - Early surgery for Medial Meniscal Posterior Root tear results in good clinical and radiological outcomes

H. Singh¹

¹Royal Derby Hospital, Trauma and Orthopaedics, Derby, United Kingdom

Background: Medial meniscus posterior root tear (MMPRT) defunctions the meniscus leading to Medial meniscus extrusion(MME) which can cause progression of arthritis. Early Root repair may improve biomechanics and clinical outcomes.
Methods: 17 patients (7 male,10 female) with MMPRT on MRI were operated with a trans-tibial pull- out repair between 2017-2019. Average age was 41.5 years (range:26-62 years) with mean BMI of 24.71. Patients were classified as type 2 (11 patients), type 4 (4 patients) and type 1 (2 patients) acccording to La Prade Classification. Hip-Knee-Ankle (HKA) xrays were taken to assess limb alignment and Kellgren-lawrence classification used to grade Osteoarthritis. Patients were followed up at 6,12 weeks and 6 monthly thereafter for an average of 20 months (range:14-26 months) with MRI at 6 weeks to assess MME post-op. Range of motion (ROM) and Lysholm scores were used to assess functional outcomes. SPSSTM v26 was used for statistical analysis and p value <0.05 considered significant.
Results: Mean pre-op score was 41.94 (range: 33-55) which improved to a statistically significant mean post op score of 70.24 (range: 60-82) (p<0.05). The mean pre-op Medial Meniscal extrusion (MME)of 3.38 ± 1.11mm reduced to 2.77 ± 0.93 post-op (p<0.05). Weak negative correlation was observed between post op MME and post-op Lysholm scores (r= -0.51, r2= 0.26). Time since symptoms {average:7.6 months (range: 2weeks to 24 months)} showed a negative correlation with post-op scores (r = -0.87; r2=0.65) and weak correlation with post- op MME(r=0.64, r2= 0.41). HKA angle (mean 178.30) and BMI bore no correlation with MME or post op scores. OA grades did not worsen over the follow-up period. Improvements in ROM were clinically beneficial but not significant statistically.
Conclusion: Early operative treatment of MMPRT results in better functional outcomes with improvements in MME and prevents progression of OA over short follow ups.

There is NO Conflict of Interest: Yes

127 - Orientating the tibial component along the Anatomical Tibial Axis may result in patellofemoral problems following total knee replacement

PA Mac Suibhne¹, M Ganapathi¹

¹Ysbyty Gwynedd, Trauma & Orthopaedics, Bangor, United Kingdom

Introduction: Optimal rotational alignment of the tibial component is important for good functional outcome following total knee replacement. Internal rotation of the tibial component has been associated with patella-femoral problems. A commonly used rotational reference is a line drawn from the deepest point of the posterior tibial sulcus to a point dividing the tibial tuberosity into its medial 1/3 and lateral 2/3 (MTA). Another commonly used axis is the Anatomical Tibial Axis (ATA) where a line connecting tibial condylar centres is transected by a perpendicular line through the tibial tuberosity.
Aim: To analyse the degree of variability in inter-axis angular relationships between the ATA and MTA.
Methods: MRI imaging from 350 knees obtained for the purpose of patient specific instrumented TKRs were analysed. The MTA and ATA were identified as described above and the variation in angular relationship between them were measured.
Results: The median angular difference was found to be 6.41^o. The minimum value was -11.950 and the maximum value was 17.69^o with an overall range of 29.64^o.
Conclusion: There is considerable variability in the angular relationships between the two axes of rotation of the proximal tibia. If rotation of the tibial component is based on the ATA, significant internal rotation of the tibial component (in relation to the patellar tendon insertion) will occur in some patients with resultant patellofemoral problems and poor outcome. However, in those patients with large variation between the two axes, tibiofemoral incongruency may occur if more constrained tibial inserts are used and consideration should be given in those cases to use a less constrained insert or mobile bearing insert to avoid the conflict between patellofemoral dysfunction and tibiofemoral incongruency.

There is NO Conflict of Interest: Yes

358 - Soft tissue landmarks for tibial baseplate rotational alignment in total knee arthroplasty. A cadaveric study

O Eseonu¹, M Mactier¹, E Ferguson², F Quondamatteo², B Jones¹

¹Glagow Royal Infirmary, Department of Trauma and Orthopaedics, Glasgow, United Kingdom, ²University of Glasgow, Thomson Building, Glasgow, United Kingdom

Background: The bony landmark of the highest point of the tibial tubercle (HPTT) is used to assess tibial baseplate rotation on post-operative CT scans in total knee arthroplasty (TKA), however this landmark can be difficult to palpate and visualise intra-operatively. Several more easily accessible soft-tissue landmarks have been proposed, including the medial border of the patellar tendon (MBPT) and the junction of the medial third of the patellar tendon (mt-PT). This study aimed to determine the relationship between the HPTT and these soft tissue landmarks, and simulate tibial baseplate rotational alignment if these landmarks were used during TKA.
 
Methods: Measurements of the patellar tendon borders relative to the HPTT were made on both knees from twenty-eight cadavers (14 male). A simulation of tibial baseplate rotation was subsequently carried out on ten post-TKA knee CT scans using the measurements obtained from the cadaveric study.
 
Results: Using the mean measurements of the MBPT, in its anatomical position, resulted in 12.68o of excessive tibial baseplate internal rotation on the CT simulation. The subluxed MBPT (sMBPT) resulted in 6.23o of external rotation; and the mt-PTresulted in 8.29 o of tibial baseplate external rotation.
 
Conclusion: Use of the anatomical MBPT may predispose to internal rotation of the tibial baseplate. However use of sMBPT or mt-PT minimise the risk of internal rotation of the tibial baseplate, which may influence TKA kinematics and development of post-operative pain.

There is NO Conflict of Interest: Yes

387 - Financial analysis of revision knee surgery at a tertiary referral centre as classified according to the Revision Knee Complexity Classification (RKCC)

M Petrie¹, S Salih¹, T Harrison¹, A Gordon¹, A Hamer¹, S Buckley¹, R Kerry¹

¹Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, United Kingdom

Background: Revision TKA (rTKA) can be complex; with greater complication risk and cost to the treating hospital than primary TKA. A rTKA regional network has been proposed with a hierarchy of case complexity appropriate to each unit. The revision knee complexity classification (RKCC) is a system proposed to triage cases to the most appropriate centre. The aim of this work was to accurately quantify costs and reimbursement for the rTKA service, classified according to the RKCC, at a tertiary referral centre.
 
Patients and Methods: A retrospective review of two consecutive financial years 2017 - 2019 was performed of all rTKA performed at our institution. Cases were classified according to the RKCC system and also by mode of failure; “infected” and “non-infected”. Financial data was acquired through PLICS.
 
Results: 159 patients underwent 188 rTKA procedures. 60 (32%) R1 revisions, 46 (24%) R2 revisions and 82 (44%) R3 revisions. Length of stay (LoS) significantly increased between complexity groups (p<0.0001) and for infected revisions (p<0.0001). Cost per inpatient episode increased significantly between complexity groups (p<0.0001) and for infected revisions (p<0.0001). The mean difference between costs and reimbursement resulted in a deficit for all groups but significantly increased with revision complexity and for infected revisions. A mean deficit of £1,903 was seen for the R1 group, £3,260 for the R2 group and £5,269 for the R3 group (p<0.0001). The total deficit to the Trust for the two-year rTKA service was £667,091. 
 
Discussion: The current levels of NHS reimbursement are inadequate for centres which offer a rTKA service. The RKCC correlates well with the increasing costs associated with the more complex cases. An increase in the most complex rTKA at major revision centres will undoubtedly place an even greater strain on the finances of these units without a significant uplift in tariff.

There is NO Conflict of Interest: Yes

448 - Revision anterior cruciate ligament reconstruction with Bone Patellar Tendon Bone Graft- 3 to 16 year result

M Kiran¹, S Roy¹, O Javed¹, N Atwal¹, H Gosal¹

¹Gloucestershire Hospitals NHS Foundation Trust, Cheltenham, United Kingdom

Background: Revision anterior cruciate ligament reconstruction(ACLR) may be influenced by previous tunnel position, tunnel widening, bone loss, graft used during primary surgery, presence of additional joint injury and infection. We present the medium term results of a cohort of patients undergoing single and two-stage revision ACLR with bone patellar tendon bone graft(BPTB).
Methods: All patients who underwent revision ACLR with BPTB between January 2004 and June 2017 were included in this study. Demographic details and symptoms were prospectively in the hospital database. Single or two stage revision was performed based on pre-operative planning. Iliac crest bone graft was used. Pre-operative and follow-up Lysholm and Tegner activity scores and return to sport(RTS) were recorded. Paired t-test was used to analyze improvement in functional score with p<=0.05 considered significant.
Results: Eighty patients with a mean age was 30.6 years were included in this study. Single stage revision ACLR was performed in 68 patients. In 12 patients(15%), revision ACLR was performed in two stages. Additional ALL reconstruction was performed in 7 patients using the iliotibial band. There was a significant improvement in Lysholm score from mean 52.4 to 85.1(p<0.001). The incidence of re-rupture in our cohort was 0%. The median Tegner score 6, RTS at any level was 66.1% and pre-injury level was 36.9%. ALL reconstruction was performed in 7 patients. The mean follow-up was 8.75 years(range 3.25-16 years).
Discussion and Conclusion: Revision ACLR is complicated by the presence of tunnel malposition and widening and additional chondral and meniscal injuries. Thorough pre-operative planning, appropriate staging of procedures, correct tunnel positioning and additional procedures to ensure rotatory stability results in low graft re-rupture rates, good functional scores and return to sport.
Implications: BPTB graft results in low rerupture rates after revision ACLR with careful planning and appropriate staging of surgery.

There is NO Conflict of Interest: Yes

652 - Arthroscopic Menisectomy in Patients Over 55: Does it Work?

M. Walker¹, P. Gallacher¹

¹The Robert Jones and Agnes Hunt Orthopaedic Hospital, Department of Sports Knee Surgery, Oswestry, United Kingdom

Background: Arthroscopic menisectomy for degenerate meniscal tears in older adults is a commonly performed procedure. We examined a cohort of patients over 55 years old at RJAH undergoing arthroscopic meniscectomy, aiming to determine their risk of needing arthroplasty surgery within 5 years, and the efficacy of the procedure.
 
Methods: We prospectively collected data between 2012 and 2013 on patients over 55 years of age undergoing arthroscopic menisectomy alone or menisectomy and chondroplasty. The patient records were reviewed in 2019 to determine if the patient’s symptoms had resolved, and whether they had required subsequent arthroplasty surgery. Data collected included:

• Patient demographics such as age, sex, employment status, symptoms, and which meniscus was injured.
• Whether patients subsequently had any form of knee arthroplasty.
• Whether the patient’s symptoms settled.

Results: 63 patients were included in the study: 28 in the menisectomy group and 35 in the menisectomy and chondroplasty group.

• Mean age was 63.9 in menisectomy group and 64.1 in the menisectomy and chondroplasty group (no significant difference P=0.85).
• There was no significant difference in the patient demographics other than employment status.
• There was a significantly higher rate of patients requiring arthroplasty in the menisectomy and chondroplasty group compared to menisectomy alone, 42.9% and 17.9% respectively P=0.034).
• There was no difference between the two groups in rates of symptoms settling (71.4% for menisectomy alone, 65.7% for menisectomy and chondroplasty P=0.63).

 Conclusions:

• Symptoms will settle in most patients undergoing arthroscopic menisectomy with or without chondroplasty.
• Patients who also undergo additional chondroplasty surgery have a significantly higher risk of requiring subsequent arthroplasty surgery within 5 years.

Implications: When considering menisectomy in older patients, caution should be used in patients with articular surface damage, however those who do not have chondral lesions have a 82% chance of not requiring joint replacement at 5 years.

There is NO Conflict of Interest: Yes

689 - Long term outcomes of a fixed all-polyethylene bearing unicompartmental knee arthroplasty in older patients

D. Bruce¹, M. Hassaballa¹, J. Robinson¹, A. Porteous¹, J. Murray¹, J. Newman¹

¹Avon Orthopaedic Centre, Southmead Hospital, Bristol, United Kingdom

Background: Medial compartment osteoarthritis can be successfully treated with a unicompartmental knee arthroplasty (UKA). An all-polyethylene fixed-bearing UKA can reduce backside wear, preserve tibial bone stock, eliminate the risk of bearing dislocation and is a lower cost implant (Koskinen et al., 2008). However, some studies suggest there may be poorer clinical outcomes and survivorship (Gladnick et al., 2015).
 
Methods: Prospective data was collected for consecutive patients undergoing implantation of an all-polyethylene fixed-bearing Uniglide UKA (Corin Ltd., Cirencester, UK) at a single tertiary hospital between November 2002 and December 2007. Patients met standard criteria for UKA implantation and the mean patient age was 70 (range 41-87). The Oxford Knee Score (OKS), American Knee Society Score (AKSS) and Western Ontario and McMaster Universities Arthritis Index (WOMAC) were collected at one, two, five, eight, 10 and 12 years postoperatively. Data were analysed with SAS University Edition (SAS Institute Inc, NC, USA).

Results: 214 fixed all-polyethylene tibia UKAs were implanted in 184 patients. Overall, Kaplan-Meier survivorship was 89.1% at 10 years. 122 UKAs were implanted in 104 patients who were at least 70 years old at the time of operation and Kaplan-Meier analysis demonstrated 10 year survivorship of 92.4%. Outcome data at 10 years or longer was available for 28 UKAs in this age group. This demonstrated that a significant improvement (p<0.001) was maintained at 10 year follow up with mean scores of: OKS 32.2 (95% CI: 27.6-36.8), AKSS 160.7 (95% CI: 142.5 – 178.9) and WOMAC 27.2 (95% CI: 22.3-32.0).

Conclusions: This fixed all-polyethylene tibia UKA has demonstrated encouraging survivorship in patients over 70 years old and appears to maintain a functional benefit at 10 year follow up. For the treatment of medial compartment osteoarthritis, it remains a reliable and relatively low-cost option and may be particularly suitable for the older patient.

Disclosure: JH Newman was the design surgeon for this implant.

697 - Predictors of Mid-late Term Revision of Knee Replacement: a Nation-wide Retrospective Cohort Study (UK SAFE)

A. Judge¹, C. Garriga-Fuentes², S. Kingsbury³, L. Smith⁴, M. Porter⁵, R. Pinedo-Villaneuva², N. Arden², P. Conaghan³

¹University of Bristol, Musculoskeletal Research Unit, Bristol, United Kingdom, ²Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences (NDORMS), University of Oxford, Oxford, United Kingdom, ³Leeds Institute of Rheumatic and Musculoskeletal Medicine University of Leeds, Leeds, United Kingdom, ⁴Health & Applied Sciences, University of the West of England, Bristol, United Kingdom, ⁵Centre for Hip Surgery, Wrightington Hospital, Wrightington, United Kingdom

Objective: Identify patients likely to require mid-late revision of knee replacement (KR) to inform targeted follow-up
Methods: Setting: Primary care using Clinical Practice Research Datalink (CPRD) data and secondary care using National Joint Registry (NJR) data linked to English Hospital Episode Statistics (HES) and Patient Reported Outcome Measures (PROMs). Patients: Primary elective KRs aged ≥18. Event of interest: Revision surgery ≥5 years after primary. Statistical methods: Cox regression modelling to ascertain influential factors of mid-late term revision. Hazard ratios (HR) and 95% confidence intervals (CI) assessed association of sociodemographic factors, comorbidities, medication, surgical variables and PROMs with mid-late term revision.    
Results: NJR-HES-PROMs data was available from 2008-2011 on 188,509 KR. CPRD-HES data covered 1995-2011 on 17,378 KR. Patients had minimum 5-years post primary surgery to end 2016. Age and gender distribution were similar across datasets; mean age 70 years, 57% female. In NJR there were 8607 (4.6%) revisions, median time-to-revision 1.8 years (range 0-8.8), with 1,055 (0.6%) mid-late term revisions. In CPRD 877 (5.1%) revisions, median time-to-revision 4.2 years (range 0.02-18.3), with 352 (2.0%) mid-late term revisions. Older age was related to significantly lower revision after 5 years (HR: 0.95; 95% CI: 0.95-0.96); male gender increased risk of revision (1.32; 1.04-1.67). Obesity (0.78; 0.64- 0.96), living in deprived areas (0.76; 0.62-0.93), and non-white ethnicity (0.63; 0.47-0.84) were associated with reduced mid-late revision. No implant factors were identified. Patients with less pain and functional limitation at primary surgery (0.29; 0.23-0.36), or moderate anxiety/depression (0.80; 0.70-0.92) had reduced risk for mid-late term revision. Risk was increased when anticonvulsants (gabapentin, pregabalin) (1.58; 1.01-2.47) and opioids (1.36; 1.08-1.71) were required prior to primary surgery.
Conclusion: There appears to be evidence of sociodemographic inequality in mid-late revision KR. Patient case-mix factors for increased risk of revision surgery indicate those requiring closer monitoring for extended follow-up.

There is NO Conflict of Interest: Yes

699 - Does high BMI predict outcomes of patients with ACL reconstruction?

M. Elnaggar¹, O. Riaz¹, B. Patel¹, A. Siddiqui¹

¹Calderdale and Huddersfield Foundation Trust, Huddersfield, United Kingdom

Objectives: Identifying risk factors for inferior outcomes after anterior cruciate ligament reconstruction (ACLR) is important for prognosis and patient information. This study aimed to ascertain if BMI, pre-operative scores, demographic data and concomitant injuries in patients undergoing ACLR affected patient-reported functional outcomes.
Methods: A prospective review collected data from a single surgeon series of 278 patients who underwent arthroscopic ACLR. BMI, age, gender, graft choice, pre-op Lysholm score, meniscal and chondral injuries were recorded. The Lysholm score, hop test and KT1000 were used to measure post-op functional outcome at one year. Multiple regression analysis was used to determine factors that predicted Lysholm scores at one year.  
Results: The mean age was 29 years, with 58 female and 220 male patients. The mean pre-op Lysholm score was 53.8. 179 patients had meniscal injuries, of which 81 were medial, 60 lateral, and 38 bilateral. 18 patients also had chondral injury and 106 patients had no other associated injury. 
Age, gender, graft type and presence of meniscal or chondral injuries did not affect one-year post-operative Lysholm scores. A BMI greater than 30, physio compliance and preoperative Lysholm scores helped predict one-year post-operative Lysholm scores (p=0.02). Pearson’s correlation found a direct link between BMI and post-operative Lysholm (p=0.03) 
Conclusions: BMI, physio compliance and pre-operative Lysholm scores are the most significant determinants of short-term functional outcome after ACLR. However, the effects of associated injuries may be apparent in the long-term as degenerative changes set in or the continued detriment resulting from the concomitant injury affect outcome.

There is NO Conflict of Interest: Yes

976 - OUTCOME STUDY OF A CONSECUTIVE SERIES OF 45 SURGICALLY-MANAGED COMMON PERONEAL NERVE PALSIES

S. Arya¹, M. Nagy¹, S. Yatham¹, C.Y. Ng¹

¹Wrightington Hospital, Trauma and Orthopaedics, Wigan, United Kingdom

Objective: We report the aetiology and outcome of common peroneal nerve (CPN) palsy. 

Methods: This was a retrospective study of patients who had undergone exploration of CPNs.
Demographics, clinical, electrophysiological, radiological and surgical findings were reviewed. The main outcome measures were Medical Research Council (MRC) grading of ankle power, and dorsal sensation (0-10) of the foot. MRC4-5 was considered a good outcome. 
 
Results: Between 2014-2020, 44 patients (45 knees) underwent CPN exploration. There were 31 males and 13 females, with a mean age of 45 years (range 19-87). 31 patients presented with complete foot drop, 7 had partial palsy, 7 had sensory only symptoms. Aetiologies included trauma (n=13), iatrogenic (n=5), primary entrapment (n=8), secondary entrapment (n=14), intraneural ganglion (n=4) and schwannoma (n=1). The traumatic group consisted of knee dislocation (n=6), tibial plateau (n=1), fibular avulsion (n=2), laceration (n=2), direct contusion (n=1) and twisting injury (n=1). 
For the traumatic and iatrogenic groups, the mean time from the index incident to surgery was 167 days. Procedures performed included neurolysis (n=35), nerve transfer (n=4), allograft (n=2), direct repair (n=1), schwannoma excision (n=1) and sural nerve graft (n=2). 
Mean follow-up duration was 12.2 months (range=1 to 18). At final review, 16 patients (42%) had recovered MRC4-5 of ankle dorsiflexion. Dorsal foot sensation improved from a mean of 4.6 to 7.5. Six patients required tibialis posterior tendon transfer. Postoperative complications included a superficial wound infection and a seroma. 
 
Conclusions: There is a spectrum of pathologies causing CPN palsy. Neurolysis can help improve function, even in delayed cases. The results of nerve transfer and grafting remain mixed. Tendon transfer is a salvage option.

There is NO Conflict of Interest: Yes

1194 - Brace before you replace? Our clinical experience of 540 consecutive knees

L. Oliver-Welsh¹, N. Patel¹, M. A. Imam¹, D. Elliott¹, P. Trikha¹

¹Ashford and St Peters Hospital, Trauma and Orthopaedics, Surrey, United Kingdom

Objectives: To investigate the clinical and cost effectiveness of an unloader brace for managing unicompartmental knee osteoarthritis.
Design: A retrospective cohort study of 540 consecutive patients managed with an unloader brace over 5 years at our unit
Setting: District general hospital in Surrey, UK
Participants: Of 540 patients, we excluded 31 patients, based on our eligibility criteria. 
We have included 509 consecutive participants (212 females and 297 males), aged 32 to 91 (mean of 59) years old, who were managed with an unloader brace for unicompartmental arthritis. 
Intervention: Each patient was prescribed an unloader brace, and followed up for a minimum of one year.
Main outcome measures
Failure of the brace was the end point; this was defined by listing those patients for surgery
Results: 447 (87.82%) participants had medial compartment knee OA, and 62 (12.18%) had lateral compartment OA. 409 (80.4%) patients managed with an unloader brace did not require surgery for their knee OA; the mean follow-up was 3 years with a minimum follow-up of 1 year. 100 participants went on to have knee surgery; 96 had a total knee replacement (TKR), and 4 underwent a high tibial osteotomy. Those with lateral OA wore their brace for a mean of 8.3 months prior to surgery, whilst those with medial OA wore the brace for 7.1 months prior to surgery. 
In our unit, we performed 141 fewer TKR’s than expected, in 2019, with an annual saving of £864,820.

There is NO Conflict of Interest: Yes

1195 - Effect of robotics on clinical outcomes in patients following TKA: 850 consecutive patient cohort

K. Marchand¹, L. Scholl², K. Taylor¹, D. Erwin¹, M. Bhowmik-Stoker², E. Hampp², R. Marchand¹

¹Ortho Rhode Island, Wakefield, United States, ²Stryker, Mahwah, United States

Introduction: Optimizing surgical technique in conventional total knee arthroplasty (CTKA) takes years to master. Learning curve with the adoption of new surgical technologies, such as robotic assistance, is often reported by case time efficiency.  The purpose of this study was to assess the patient focused effects of new technology adoption in a large case controlled, cohort study.  We specifically investigated adverse events (AEs) and patient reported outcomes (PROs) in the first 6 months of a single surgeons’ robotic adoption.
Methods: Total knee arthroplasty was performed by a single surgeon on 850 patients. This study considered the last 150 CTKAs prior to adopting (Robotic Assisted Total Knee Arthroplasty) RATKA and first 700 RATKAs after transitioning. All patients received the same implant design, and demographics were similar between groups. AEs and PROs were collected through 6-months postoperatively. PRO was collected through the reduced-WOMAC survey (r-WOMAC). Statistical analysis was performed using a one-way ANOVA (alpha = 0.05).
Results: Patients in the RATKA cohort had significantly improved mean 6-month postoperative r-WOMAC physical function (4±5 vs. 5±4 points, p=0.010), and total scores (7±8 vs. 8±7 points, p=0.023) compared to the CTKA group. Although not statistically significant, RATKA had less r-WOMAC pain (3±3 vs. 3±3 points, p=0.101). At 6-months, there were no reported aseptic failures for the RAKTA and CTKA groups and equivalent rate of manipulations under anesthesia (MUA).
Discussion: This study demonstrated improved clinical outcomes, no revisions, and equivalent rate of MUA during the adoption phase of a new operative technology. PROs and AEs reported in this study corroborate literature from other centers on clinical performance on RATKA. Longitudinal follow-up is needed to support the initial impressions from this analysis.

Disclosure: Laura Scholl, Emily Hampp, and Manoshi Bhowmik-Stoker are paid employees of Stryker. Dr. Robert Marchand is a paid consultant of Stryker. 

1273 - Analysis of the relationship between surgeon procedure volume and the risks of revision and deep infection after total knee arthroplasty using a propensity matched cohort study

T. Okoro¹, S. Tomescu², J.M. Paterson³, B. Ravi²

¹Robert Jones and Agnes Hunt Orthopaedic Hospital NHS Foundation Trust, Arthroplasty, Oswestry, United Kingdom, ²Sunnybrook Holland Orthopaedic and Arthritic Center, Toronto, Canada, ³Institute for Clinical Evaluative Sciences (ICES), Toronto, Canada

Background: To identify a threshold in annual surgeon volume associated with increased risk of revision (for any cause) and deep infection requiring surgery following primary elective total knee arthroplasty (TKA), and to quantify this risk, if any.
Methods: A propensity score matched cohort study was undertaken in Ontario, Canada. The participants were 169,713 persons who received their first primary TKA between 2002-2016, and were followed for three years post-operatively. The outcome measures assessed were revision arthroplasty (for any cause), and the occurrence of deep surgical infection requiring surgery at three years follow-up.
Results: Based on restricted cubic spline analysis, the threshold for increased probability of revision (for any cause) and deep infection requiring surgery was <70 cases per year. After matching of 51,658 TKA recipients from surgeons performing <70 cases/year to TKA recipients from surgeons with greater than 70 cases/year, patients in the former group had a higher rate of revision (for any cause) within three years (2.23% (95% CI 1.39 - 3.07) versus 1.70% (95% CI 0.85 – 2.55) ; HR 1.33, 95% CI 1.21-1.47, p<0.0001) and deep infection requiring surgery within three years (1.29% (95% CI 0.44 - 2.14) versus 1.09% (95% CI 0.24 – 1.94) ; HR 1.33, 95% CI 1.17-1.51, p<0.0001).
Conclusions: In a cohort of primary TKA recipients, we found that cases performed by surgeons who had performed fewer than 70 TKA procedures in the year prior to the index TKA were at 31% increased relative risk of revision (for any cause), and 18% increased relative risk for deep surgical infection requiring surgery, at 3 years follow up.
Implications: Three years following primary TKA, the risks for revision (for any cause) or infection requiring surgery is higher in patients whose surgeons have carried out less than 70 procedures in the preceding year.

Disclosure: This study was supported by a grant from the Canadian Institutes of Health Research and by the Institute for Clinical Evaluative Sciences, a non-profit research institute funded by the Ontario Ministry of Health and Long-Term Care.

1306 - LONG TERM SURVIVORSHIP AND CLINICAL OUTCOMES OF NAVIGATED LATERAL OPENING WEDGE DISTAL FEMORAL OSTEOTOMY FOR OSTEOARTHRITIS OF LATERAL COMPARTMENT OF KNEE

V. Kandhari¹, D. Angadi¹, D. Myat¹, B. Fritsch¹, D. Parker¹, M. Coolican¹

¹Sydney Orthopaedic Research Institute, Orthopaedic Knee surgery, Chatswood, Australia

Objectives: To determine the outcomes and survivorship of navigated lateral opening wedge distal
femoral osteotomy (DFO) for valgus knees with lateral compartment arthrosis.
Methods: Navigated lateral opening wedge DFOs operated between 2006 and 2012 were included.
Patients were contacted to get information on patient reported outcomes and complications. Data
on conversion to arthroplasty was verified with the Australian National Joint Replacement Registry.
Prospectively collected data including demographics, limb alignment, and cartilage and meniscal
status were analyzed to evaluate their influence on outcomes and survivorship.
Results: Nineteen DFOs in 17 patients (11 males) with mean age 46.6 years were included. The mean
pre-operative mechanical alignment 7.1° valgus was corrected to 2.1° varus and mean preop flexion
contracture 6.8° was corrected to 1°. Survivorship at mean of 9.1 years follow-up was 78.9%; 4 DFOs
were converted to TKA at mean follow-up of 5.5 years. Additional procedures (except conversion to
TKA) occurred in 10 knees (52.6%) including arthrolysis, hardware removal, bone grafting and
revision fixation. Patients with ICRS grade 2 or more cartilage wear in medial compartment and
higher pre-op valgus had significantly higher likelihood of conversion to TKA (PCC – 0.72). At long-
term follow-up the mean IKDC score was 55.35 and KOOS scores were symptoms-57.93, pain-72.71,
daily living-83.5, sports related-60.36 and quality of life-43.93.
Conclusions: The long-term survivorship of navigated lateral opening wedge DFOs is 78.9%. Patients
with early stages of cartilage wear in the medial compartment and more higher pre-op valgus have
significantly higher chance of conversion to TKA.

Disclosure: *Vikram Kandhari, Darshan Angadi, Darli Myat - None.
Brett Fritsch, David Parker, Myles Coolican - Consulting work for 360 Knee Systems, Global Orthopaedics, Omni, Smith and Nephew; Institutional support Zimmer, Smith and Nephew, Global Orthopaedics, Corin, Arthrex; Paid presentations Smith and Nephew, J&J DePuy, Medacta.

1476 - "Can we ignore the patello-femoral joint?" Severe medial patello-femoral osteoarthritis does not diminish the excellent outcomes of isolated fixed-bearing partial knee arthroplasty

N. London¹, A. Mannan², C. Bennett³, K. Mason², E. London⁴, T. Idrees⁵, W. Manning², J. Ansari², D. Duffy²

¹Harrogate District hospital, Department of Trauma & Orthopaedics, Harrogate, United Kingdom, ²Harrogate, Department of Trauma & Orthopaedics, Harrogate, United Kingdom, ³Harrogate, Harrogate District hospital, Harrogate, United Kingdom, ⁴West Middlesex Hospital, Middlesex, United Kingdom, ⁵Harrogate District hospital, Harrogate, United Kingdom

Introduction: Patello-femoral osteoarthritis (PFJOA) is still viewed by many surgeons as a contraindication to isolated medial partial knee arthroplasty (PKA), despite published outcomes from mobile-bearing advocates. This study, supported by The European Knee Society, prospectively examined clinical outcomes from a large series of fixed-bearing medial PKA.
 
Methods: We prospectively studied 240 consecutive, fixed-bearing PKA cases. Broad selection criteria included patients with PFJOA providing it was not significantly symptomatic. Patients diagnosed with extensive lateral PFJOA were excluded. Pre and post-operative (1 and 2-year) data documenting OKS, KOOS PS, UCLA and FJS-12 was collected. Intra-operative examination was made of each compartment with regards to severity and location of arthritic disease.  
 
Results: From February 2017, 240 fixed-bearing PKA were performed in 229 consecutive patients. Mean age at time of surgery was 68yrs (range 41-89), mean BMI 29.1 (range 20 – 47). Mean OKS increased from 24.9 (pre-op) to 43.7 and 44.4 at one and two years respectively. Mean KOOS PS, UCLA (1-10) and FJS-12 all showed improvement to 83.1, 6.6 and 76.6 (one year) and 84.9, 6.5 and 79.8 (two years post-op). Grade III and IV osteoarthritis of the medial, central and lateral PFJOA was observed in 99, 86 and 28 cases respectively. No significant difference was demonstrated in 1 or 2-year post-operative outcomes with comparison of cases demonstrating nil PFJOA vs those with grade III / IV PFJOA involving medial, central or lateral facets. 95.9% patients declared they were satisfied (one-year) and only one patient has required a revision procedure (tibial loosening).

Discussion and Conclusion: Excellent functional outcomes are confirmed with fixed-bearing PKA for the treatment of severe medial compartmental arthritis. Our study supports the use of isolated fixed-bearing PKA in patients with co-existing PFJOA and such patients should be included in the selection criteria although severe lateral PFJOA remains a relative contraindication.

Disclosure: Nick London / David Duffy: Zimmer Biomet 

1613 - Patients have a wider stance following valgus high tibial osteotomy

A. Kinghorn^1,2, J. Bowd¹, G. Whatling¹, C. Wilson², D. Mason¹, C. Holt¹

¹Cardiff University, The Biomechanics and Bioengineering Research Centre Versus Arthritis, Cardiff, United Kingdom, ²Cardiff and Vale University Health Board, Department of Trauma and Orthopaedics, Cardiff, United Kingdom

Objectives: Valgus high tibial osteotomy (HTO) represents an effective treatment for patients with medial compartment osteoarthritis (OA) in a varus knee. However, the mechanisms which cause this clinical improvement are unclear. Previous studies suggest a wider stance gait can reduce medial compartment loading via reduction in the external knee adduction moment (KAM); a measure implicated in progression of medial compartment OA. This study aimed to measure whether valgus HTO is associated with a postoperative increase in static stance width. 
 
Methods: 32 patients, recruited in the Biomechanics and Bioengineering Centre Versus Arthritis HTO study, underwent valgus (medial opening wedge) HTO. Weightbearing pre- and post- operative radiographs were taken showing both lower limbs. The horizontal distance, measured from a fixed point on the right talus to the corresponding point on the left, was divided by the talus width to give a standardised “stance width” for each radiograph. The difference between pre- and post- operative stance width was compared for each patient using a paired sample t-test. 
 
Results: Preoperatively, mean stance was 4.00 talar-widths but postoperatively this increased to 5.41. This mean increase of 1.42 talar-widths was statistically significant (p=0.001) and represents a mean proportional increase in stance width of 35.5% following HTO. Of the 32 patients, 23 showed increased stance width and 9 decreased (range -4.64 to 6.00 talar-widths). 
 
Conclusions: These findings indicate an association of frontal plane surgical realignment at the proximal tibia via a medial opening wedge HTO with an increased stance width on postoperative radiographs. Considering both wider stance gait and HTO have been shown to affect the progression of medial compartment OA, these results may explain one mechanism contributing to the efficacy of HTO surgery. However, the range of changes in stance width suggests significant variability in how patients adapt at a whole-limb and whole-body level following HTO.

There is NO Conflict of Interest: Yes

​​​​​1724 - The impact of ethnicity on knee joint laxity in the osteoarthritic population

C. Thomson¹, J. Setsoafia¹, S. Deshpande¹

¹New Cross Hospital, Trauma and Orthopaedics, Wolverhampton, United Kingdom

Introduction: Current understanding suggests that soft tissue balancing has a crucial role to play in the outcome of total knee arthroplasty (TKA), but appropriate balancing is often based on subjective assessment and experience. There appears to be considerable variation between individuals, genders, and ethnic groups when it comes to “normal” varus/valgus knee laxity. However, much of the existing data relates to healthy young volunteers, and it is not clear how this information should map against the elderly osteoarthritic population who require TKA. Computer navigated TKA procedures routinely generate precise data about varus/valgus laxity as an immediate prelude to the arthroplasty procedure. We wished to use a database of such measurements to understand “normal” pre-operative varus/valgus laxity, and how this was influenced by both gender and ethnicity.
Method: The Precision Navigation System (Stryker, Kalamazoo, Michigan, USA) is used by a single surgeon at our institution to perform all TKA procedures. Dynamic varus/valgus laxity measurements (typically between 0-50degrees of extension/flexion) are recorded using infrared sensors attached to pins in both femur and tibia at the start of the procedure. We retrospectively analysed data collected between 2015-2019, comparing maximum varus/valgus laxity between genders and ethnic groups. The demographic data was cross checked with the clinical record.
Results: We obtained complete data for 146 TKA procedures, including 87 ethnic south asian patients and 59 caucasian patients. M:F split was 1:1.47. The median maximum varus/valgus laxity was 13.06 degrees in the asian knees and 10.14 degrees in the caucasian knees (Mann-Whitney U= 4007.5, p<0.001, two tailed). The median maximum varus/valgus laxity was 12.00 degrees in the female and 11.96 degrees in the male knees (Mann-Whitney U= 2625.5, p<0.816, two tailed).
Conclusion: Ethnicity has a significant impact on pre-operative varus/valgus laxity and should be considered when making subjective judgements about appropriate soft tissue balancing in TKA.

There is NO Conflict of Interest: Yes

1789 - Multi-ligament knee injury: Staged management with Posterior Cruciate Ligament (PCL) bracing is a viable treatment option

C. Goodland¹, M. Arneill¹, L. O'Connor¹, P. Archbold¹, R. Napier¹, C. Stevenson¹

¹Royal Victoria Hospital, Trauma and Orthopaedics, Belfast, United Kingdom

Background: The ideal management of PCL injuries in Multi-ligament Knee injury (MLKI) remains uncertain and controversial. The Royal Victoria Hospital, Belfast, is the tertiary referral center for multi-ligament knee trauma in Northern Ireland. The aim of this study was to review the management and clinical outcome of PCL injuries.
Methods: Patients were identified from the Trauma Research Database from 2011-2019. Data were obtained from patient’s clinical notes, telephone consultations and clinical review.
Results: In total 84 patients (87 knees) had a MLKI, 61 of which involved the PCL. 5 patients were excluded from analysis (one had less than 12-month follow-up, one primary amputation and three patients had grade 1 injuries managed conservatively). Of the remaining 56 PCL grade 2-3 injuries: 40 were treated conservatively in a dynamic PCL brace for 3 months. The remaining 16 patients underwent surgical management consisting of; early fixation of PCL tibial avulsion fracture (3), definitive management in an external-fixator (5), and early total reconstruction (8). At 12-month minimum follow-up, only 3 patients treated conservatively had symptomatic instability requiring delayed PCL reconstruction (7.5%). There were no complications in the bracing group.
Conclusion: The management of multi-ligament knee injury should be individualized to the patient and injury pattern. Our data highlights that the use of dynamic PCL bracing is not only safe and effective but also reduces the requirement and unnecessary risk associated with PCL reconstruction.

There is NO Conflict of Interest: Yes

1858 - RETURN TO PLAY AND GRAFT RUPTURE RATES IN YOUNGER PATIENTS FOLLOWING ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION

D. Cooper¹, P. McQuail¹, E.P. Murphy¹, F.J. Shannon^1,2

¹University Hospital Galway, Dept. of Orthopaedics, Galway, Ireland, ²Bon Secours Hospital, Dept. of Orthopaedics, Galway, Ireland

Introduction: The anterior cruciate ligament (ACL) is one of the most commonly injured ligaments of the knee. Patients who undergo ACL reconstruction (ACLR) often express concern with regards to the likelihood of graft rupture. Rates of graft rupture vary throughout the literature, (1.4%-25%). This wide range suggests a multifactorial cause for graft rupture.
Our primary objective was to determine the rate of graft rupture in a younger patient cohort (<20 years old) who have had ACLR performed by a single surgeon. Secondary objectives included ascertaining patient and surgical characteristics associated with re-rupture, and establishing correlations between risk factors for rupture and return to play (RTP).
Methods: All cases of primary ACLR for patients under 20 performed by a single surgeon between 2010 and 2018 inclusive with a minimum of 12 months follow-up were included. We retrospectively collected data on RTP rates, patient factors and surgical factors. A telephone survey was used to further these data sets.
Results: 104 patients met our inclusion criteria. The graft rupture rate was 8.65%. 83.81% of patients had a successful RTP following ACLR. Of the 16.19% who did not return to play, 52.9% had a hamstring graft while 47% had a BPTB reconstruction. 14% reported a drop in their level of sport/activity while 83% returned to their pre-injury levels or better. 41.9% of patients reported a repeat injury to their ipsilateral knee on follow-up. 79.5% of these (33% of total), required/sought medical attention, with 45% of the re-injured cohort undergoing some form of surgical management. 16% of patients throughout the entire cohort suffered a contralateral ACL injury following their ALCR.
Conclusions: This retrospective study provides us with an overview of the rates of graft rupture, contralateral injury, RTP rates, the level of RTP, and patient satisfaction across a range of varying patient and surgical factors.

There is NO Conflict of Interest: Yes

19 - Long term surgical management of symptomatic osteonecrosis and utility of core decompression of the femoral head in young people with acute lymphoblastic leukaemia recruited into UKALL 2003

A. Fishlock¹, N. Amin¹, J. Kraft¹, C. Holton¹, A. White¹, B. James¹, S. Kinsey², R. Feltbower

¹Leeds General Infirmary, Leeds, United Kingdom, ²Leeds Children’s Hospital, University of Leeds, Leeds, United Kingdom

Aims: It has been recognised that osteonecrosis can cause considerable morbidity in young people being treated for acute lymphoblastic leukaemia (ALL). The purpose of this work was to determine surgical procedures used for osteonecrosis in this population in the UK, timing of procedures and sequential procedures used in different joints. We also aimed to ascertain if core decompression (CD) is warranted as a method of preventing joint collapse.

Patients and methods: UK treatment centres were contacted to obtain details regarding surgical interventions and long term outcomes for patients who were treated for ALL and developed osteonecrosis in UKALL 2003. Radiographic imaging for patients with osteonecrosis affecting the femoral head was requested. Diagnostic imaging was used to score all lesions, with subsequent imaging used to determine final grade. Kaplan-Meier failure time plots were used to compare use of CD with no joint preserving surgical intervention.

Results: Detailed information was received for 85 patients who had developed osteonecrosis during the course of their ALL treatment. A total of 206 joints were affected by osteonecrosis. Of all joints affected by osteonecrosis, 21% required arthroplasty, and 43% of all hips affected went on to be replaced. CD was performed in 30% of hips affected by osteonecrosis. The majority of hips were grade 4 or 5 at initial diagnosis of osteonecrosis. There was no significant difference in time to joint collapse between those joints in which CD was performed, compared with no joint preserving surgical intervention.

Conclusion: There is a high burden of surgery in young people who have received treatment for ALL and have developed osteonecrosis. These results suggest that CD of the femoral head in this patient group does not delay or improve rates of hip survival.

There is NO Conflict of Interest: Yes

24 - The cuneiform osteotomy for patients with slipped capital femoral epiphysis (SCFE): A 14-year experience from a tertiary paediatric referral unit

J Craven¹, A Truss¹, V Bucknall¹, R Walton¹, C Bruce¹, C Talbot¹

¹Alder Hey Children's Hospital, Orthopaedics, Liverpool, United Kingdom

Background: To report the outcomes of the cuneiform osteotomy through an anterior approach in the treatment of slipped capital femoral epiphysis from a tertiary paediatric referral unit over a 14 year period.

Methods: A single centre retrospective study was undertaken. All patients presenting with SCFE between 2004 and 2018 treated with cuneiform osteotomy through the anterior approach were included. Patient demographics, type of SCFE and outcomes were recorded.

Results: 37 cuneiform osteotomies [24 left;13 right] were performed in 35 patients [22 females;13 males]. The mean age at surgery was 12.2 years. The mean pre op slip angle was 53 degrees [range 88-25] with a mean correction of 43 degrees [range 18-81], and a residual slip angle of 10 degrees [2-29]. There were 32 unstable and 5 stable SCFE, of which 20 had an ‘acute’,13 ‘acute on chronic’ and 4 ‘chronic’ presentation. The mean number of days from symptom onset to surgery was 39.1 days (1- 180). Minimum follow up was 14 months. The overall rate of avascular necrosis (AVN) was 35.1%, developing in 13 of the 37 hips [11 unstable, 2 stable]. The mean presentation of AVN was 5.3 months following surgery. Other complications included chondrolysis (n=1), implant failure (n=2), hip dislocation (n=1), meralgia paraesthetica (n=2), delayed union (n=1), heterotrophic ossification (n=3), contractures (n=2) and wound infection (n=1). 14 patients required further surgery, 13 as a result of AVN including; removal of metalwork, hip distraction, pelvic support osteotomy, soft tissue releases, epiphysiodesis. 4 patients had a residual leg length discrepancy > 2.0cm.

Conclusion: Our experience of the cuneiform osteotomy highlights the effectiveness in correcting deformity of the slipped capital epiphysis. However, the risk profile including AVN described is significant and must be considered when counselling patients undergoing this procedure.

There is NO Conflict of Interest: Yes

29 - The unstable slipped capital femoral epiphysis: Does timing and type of surgery really matter?

J Craven¹, A Truss¹, V Bucknall¹, R Walton¹, C Bruce¹, C Talbot¹

¹Alder Hey Children's Hospital, Orthopaedics, Liverpool, United Kingdom

Background: We undertook this retrospective cohort study to determine the outcomes of surgical management of the unstable slipped capital femoral epiphysis (SCFE)

Methods: All patients diagnosed and treated at Alder Hey Children’s Hospital with a Loder classified unstable SCFE over 20 years were identified. Patient demographics, timing to theatre, surgical procedure, avascular necrosis (AVN) and outcomes were reviewed. Follow up was taken a time to last clinic review or time to discharge.

Results: There were 67 unstable SCFE in 65 patients [37 Left: 30 Right]. Mean age was 13 years [7 to 16]. Thirty-two cuneiform osteotomies, 30 closed reduction and percutaneous pinning (CRPP), 3 ‘Parsch’ reduction and pinning, and 2 surgical hip dislocations with modified Dunn osteotomy were performed. 5 patients (4 CRPP and 1 ‘Parsch’) lost to follow up. The overall AVN rate was 34.3% [n=23]; cuneiform [34%; n=11/32], CRPP [42%; n=11/26], ‘Parsch’ [50%; n=1/2], Modified Dunn [0%; n=0/2]. No difference was found between cuneiform and CRPP (p=0.268). Median follow up 31 months [6-71]. Mean time to AVN following surgery was 5.5 months [6 weeks – 14 months]. The relative risk for AVN rates in CRPP when treated <24 hours and >24 hours was 0.86, p=0.371. The relative risk for AVN rates in cuneiform when treated <7 days and >7 days was 0.95, p=0.472. Further surgery and leg length discrepancy were more frequent in the cuneiform group compared to CRPP group (40% vs. 23% and 31% vs 17% respectively).

Conclusion: Our experience highlights the AVN and complication rates are similar in both cuneiform osteotomy and CRPP groups for the unstable SCFE. Despite previous work, timing may not have a significant effect on AVN rates. An adequately powered multicenter national trial is required to determine the gold standard treatment for the ‘unstable’ SCFE.

There is NO Conflict of Interest: Yes

225 - OVER THE TOP ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION WITH LATERAL RECONSTRUCTION IN PATIENTS WITH OPEN PHYSES: A LONG-TERM FOLLOW-UP STUDY

R. Lanzetti¹, V. Pace², A. Ciompi³, D. Perugia⁴, M. Spoliti¹, F. Falez³, C. Park⁵, A. Caraffa²

¹San Camillo - Forlanini Hospital, T&O, Rome, Italy, ²University of Perugia, T&O, Perugia, Italy, ³Santo Spirito Hospital, T&O, Rome, Italy, ⁴La Sapienza University, T&O, Rome, Italy, ⁵North West Thames, T&O, London, United Kingdom

Anterior Cruciate Ligament (ACL) rupture in skeletally immature athletes is becoming an injury with increasing incidence. Choices of treatments are still debated, including conservative management vs various surgical techniques. Lack of long-term reports has been highlighted in the literature. Our aim was to evaluate long-term results of ACL reconstructions performed in skeletally immature patients using the Over the Top technique with lateral extra-articular tenodesis.
Retrospective study. All surgeries performed by same team. 42 patients included. All patients had preoperative and postoperative radiological studies. 30 males-12 females. Average age: 12.5 years (range 11-14 years). Average follow-up: 96.1 months. Clinical evaluation: Pedi-IKDC, Tegner-Lysholm, KT-1000, plain radiographs. Standardized rehabilitation protocol.
No instability nor leg length discrepancy recorded. Time from injury to surgery: 3.2 months (range 0.5-5). Average pre-op Tegner-Lysholm and Pedi-IKDC: 55 and 40; 94.8 (p<0.05) and 94.78 at final follow-up (p<0.05). Average post-op (1 month) Tegner-Lysholm: 75 (range: 62-79). Median post-op Tegner: 8. Mean side-to-side (KT-1000): 1,2mm. 22 patients could go back to pre-injury sport activity. Average rehabilitation: 7.3 months. The most common sports were soccer (35.1%), skiing
(21.7%), and rugby (22.4%).
A significant amount of cases was included in our structured standardised study and follow up. Functional scores were overall excellent. Excellent results are testified by final achievement of 22 patients to go back to pre-injury sport activity in keeping with literature. Our experience exhibited a low complication rate and no metalwork failure. We correlate our results to the use of the over the top technique with lateral extra-articular tenodesis. The studied procedure seems to be an excellent option strategy and an effective, feasible and safe technique when treating ruptured ACLs in skeletally immature patients. Studies with higher level of evidence are needed in order to further validate our results.

There is NO Conflict of Interest: Yes

348 - Day-case pelvic osteotomy for Developmental Dysplasia of the Hip (DDH)

D Moore¹, G Sheridan², DP Moore²

¹Children's Health Ireland at Crumlin, Orthopaedics, Dublin 12, Ireland, ²Childrens Health Ireland at Crumlin, Orthopaedics, Dublin 12, Ireland

Background: We report the results of a pilot study analysing the feasibility and financial implications of performing pelvic osteotomies for DDH as day-case's. This is a novel process that hasn't been described to date in the literature.

Methods: This was a prospective study analysing Salter and Pemberton osteotomies for DDH over a 3 year period from 2017 to 2019. Anaesthetic involvement with a dedicated analgesic protocol on discharge was provided along with parental instruction and phone call the following day. Clinical review was as per standard practice. Economic costings were sourced from the official ‘HSE specialty costing report 2018’.

Results: Eighty-four osteotomies were performed from 2017 to 2019. Thirty-five were performed as day-cases. Considering the standard number of in-patient days for the same procedure is 2 days, a reduction in 70 in-patient bed-days were reported. Discharge costs for a single inpatient were €5,752. For 35 in-patient osteotomies, this would have amounted to €201,320. The total discharge cost of a day case was €2,670. Calculating the difference, a total saving of €102,696 was made by the hospital. Only 7 patients re-attended due to inadequate analgesic control, and all were discharged without issue the following day. The savings made per patient amounted to €3,082 for every osteotomy performed as a day-case.

Conclusion: Day case pelvic osteotomies can significantly reduce the number of inpatient bed days in an elective paediatric setting. Economic gains made by treating only 35 patients in this manner amounted to €102,696. There was no adverse impact on the standard of clinical care. We propose that the introduction of day case pelvic osteotomy procedures can significantly improve the cost-effectiveness of managing DDH in a paediatric population. Provided there is a stringent analgesic protocol provided on discharge with close clinical follow-up, this is a safe and effective innovation in this field.

There is NO Conflict of Interest: Yes

362 - Litigation costs in paediatric trauma and orthopaedics: a 15 year trend comparison to paediatric surgery

G Hodhody¹, S Afzal¹

¹Manchester Childrens Hospital, Paediatric Orthopaedics, Manchester, United Kingdom

Background: The surgical management of the paediatric patient is challenging and complex. There are many factors to consider in the diagnosis and treatment of a paediatric patient, in particular the inclusion of an adult with parental responsibilities with whom the legal right of consent lies.
This study looks at litigation trends in the paediatric population. Much work has been published looking at litigation in the adult patient, however we believe this to be the first study to scrutinise the litigation figures in the UK for the paediatric patient.

Methods: We focused on a 15 year time frame, the financial years of 2003-2018. Data was obtained from NHS Resolution, via the Freedom of Information Act 2000. All claims pertaining to children aged 16 and under who had received care under these subspecialties, were collated.

Results: A total of 1435 closed claims were found resulting in £162 million of costs across both specialties. 1119 claims (79%)  were for T&O with 728 claims (65%) paying out for damages. 44% of total claims (n=318) were due to delay in treatment or diagnosis and 10% (n=44) were due to intraoperative complications. A total of £45million was paid out for delayed diagnosis and delayed treatment with a grand total of £112million paid out over 15 years in T&O alone.

Conclusion: Litigation is a growing burden on the NHS budget with increasing demands every year.
Delays in diagnosis and treatment were identified as the biggest cause for litigation in the paediatric orthopaedic population which is in keeping with previous studies in the adult population.

Implications: A large proportion of the claims from their cause data can be recognised as potentially avoidable. The results point to the need for further education and reflection within this aspect of trauma and orthopaedics.

There is NO Conflict of Interest: No

866 - Can Virtual Reality headsets be used safely as a distraction method for Paediatric Orthopaedic patients? A feasibility study.

K. Shepherd¹, Y. Shanmugharaj², M. Kokkinakis¹, O. Kattan²

¹Evelina Children's Hospital, Paediatric Orthopaedics, London, United Kingdom, ²Kings College London, London, United Kingdom

Background: Virtual Reality (VR) has been shown to decrease pain and anxiety in clinical areas. Venepuncture, Plaster Room procedures and the Operating Theatre environment can provoke anxiety in Paediatric Orthopaedic patients. The purpose of this study was to assess the feasibility of the ‘Rescape DR:VR’ headset as a distraction method within these Paediatric Orthopaedic settings.

Methods: An internal risk assessment by medical engineers was carried out to determine the safety of the VR-Headset in the three clinical areas. The device was deemed safe to be used only in the Venepuncture and Plaster Rooms, while further investigation is needed to establish its safety in the operating theatre/anaesthetic room. Thirty-three children (age range:2 -15 years) were given the option to use a VR-headset while they underwent venepuncture or a cast procedure. Anxiety scores, measured on a Likert scale, were collected pre and post-procedure. Participants were asked if they would use the device again. Subjective feedback was also collated from the supervising clinical staff.

Results: 64% (21) showed a reduction in anxiety scores, 27% (9) had no change in score; all scores being mild, 1-3 on the Likert scale. 6% (2) showed an increase in post procedure score. All participants stated they would use the device again. One patient declined the headset. Health professionals also gave positive subjective feedback and they would all use it again with their paediatric patients. No adverse events were recorded.

Conclusion/Findings: The ‘Rescape DR:VR’ headset has been found to be safe and a feasible distraction method for use within the Venepuncture and Plaster Room. Further research is required to assess its use safety and effectiveness in other clinical areas including the Paediatric Orthopaedic operating theatre.

Disclosure: The Virtual Reality Headset and kit was loaned to the Evelina Children's Hospital by Rescape Innovation Ltd for a trial period and returned after the designated period.

There is NO Conflict of Interest: No

1067 - 128 consecutive ACL reconstructions at a Children's Hospital: Low revision rates with a delayed return to sports at 5 years mean follow up.

H. Mills^1,2, P. Jose³, D. O'Dowd³, G. Davies³, F. Ali^3,4, N. Nicolaou³ 
1University of Sheffield, Sheffield, United Kingdom, ²Kingston Hospital, London, United Kingdom, ³Sheffield Children's Hospital, Sheffield, United Kingdom, ⁴Chesterfield Royal Hospital, United Kingdom 

Background: Isolated studies of Paediatric ACL reconstruction are limited. Re-operation rates are high with little mid-term data on functional outcomes. This study reports on the functional outcomes and reoperation rates for a young cohort treated at one institution with a delay in return to contact sports of minimum 1 year from the time of surgery.

Methods: Ethical approval for the study was granted. All patients with >1 year of follow up post-surgery were contacted and asked to complete functional scores including Pedi-IKDC, Pedi-KOOS, Tegner, IKDC, KOOS and EQ-5D depending on age. Data on surgical technique, bone age, post-op growth disturbance/ mechanical axis deviation, re-operation or revision was collected.

Results: 138 cases of primary ACL reconstruction with at least one year follow up were identified. 10 cases were excluded as congenital ACL. Mean follow up was 5 years (range 1-14) for the 128 patients treated for traumatic ACL rupture at a mean age of 15 (6-17). None were treated within 6 weeks of injury. 86% underwent transphyseal reconstruction with hamstring graft. Re-ruptures occurred in 11% of patients, 64% requiring revision. Contralateral rupture occurred in 5%. 63% had a meniscal tear at the time of surgery, treated with medial menisectomy (12%), medial repair (16%), lateral menisectomy (16%) and lateral repair (19%). Further meniscal surgery was required in 18% of which 43% had revision fixation, 61% meniscectomy and 4% meniscal transplant. There were 2 radiological valgus deformities not requiring treatment and 4 further arthroscopies. 1 case of failure was due to tunnel malposition. There were statistically significant improvements in functional scores from pre-operative values with improvement over time.

Conclusions: Meniscal injury rates are high in this cohort due in part to delay in presentation and treatment. Reinjury rates are low, possibly due to a determined effort to delay return to pivoting sports.

There is NO Conflict of Interest: No

1124 - A prediction model for treatment decisions in distal radial physeal injuries. A multicentre retrospective study

S. Kannan^1,2, H. Hong Chong³, A. Fadulelmola¹, H. Lennox-Warburton¹, G. Mcconaghie⁴, B. Emmerson⁵, S. Venkatachalam⁶, A. Abraham⁷, P. Henman⁶

¹Health Education England- North East, Newcastle, United Kingdom, ²Newcastle University, Newcastle, United Kingdom, ³Health Education England- East Midlands, Leicester, United Kingdom, ⁴Health Education England- West Midlands, Oswestry, United Kingdom, ⁵Northumbria Hospitals NHS Foundation Trust, Newcastle, United Kingdom, ⁶Newcastle Upon Tyne Hospitals NHS Foundation trust, Newcastle, United Kingdom, ⁷University Hospitals of Leicester, Leicester, United Kingdom

Background: Distal radius fractures are the most frequent fractures seen in the pediatric  population and they constitute approximately 1/6 of fractures treated in the emergency department. About 15% of these fractures involve physis. Despite being common there are no clearly defined treatment guidelines for the management of distal radial physeal injuries(DRP). To support shared decision-making, we developed the first prediction model for patients with DRP. The personalised model, predicts the risk of deformity, physeal damage and remanipulation. Our aim was to identify patients who have a high risk of poor radiological outcome the following injury and develop a prediction model. To our knowledge, this is the single the largest study on DRP injuries.

Methods: The study was conducted across multiple centers in the UK. We included all patients under 16 years with isolated DRP injuries. Data were analysed using SPSS. Nomogram was developed using R. The predictive accuracy of the validated model was assessed using sensitivity, specificity, PPV, and NPV.

Results: Our study included 479 patients. 6.6%(32/479) patients had a second procedure. The rate of physeal closure was 10.2%(49/479). 6%(28/479) of patients had a distal radius deformity at the end of follow-up. The occurrence of distal radius deformity had a strong correlation with age (p 0.04) and immobilization duration (p 0.003). ROC analysis showed that age >12.5 years (p 0.006) and sagittal angulation of >21.7° (p 0.002) had a higher odds of distal radius deformity. Immobilisation < 4.5 weeks (p 0.01) had a higher revision rate. The nomograms showed good calibration, with a sensitivity of 70% and specificity of 75%.

Conclusion: The prediction model is the first of it’s kind for prognosticating the outcomes for distal radial physeal injuries. The developed model shows good sensitivity and specificity to provide a reliable prediction of poor outcomes.

There is NO Conflict of Interest: Yes

1625 - QUALITY OF LIFE IMPROVEMENT AFTER PAEDIATRIC TOTAL HIP REPLACEMENT

J. Barrow¹, A. Foster², M. Kenawey², T. Board¹

¹Wrightington, Centre for Hip Surgery, Wigan, United Kingdom, ²Royal Manchester Children's Hospital, Trauma and Orthopaedics, Manchester, United Kingdom

Background:  The decision to undertake THA in a child is complex and surgery challenging. Pre-operatively patients’ typically have significant pain and mobility restriction. Little is published on the functional gains after THA in this group. The aim of this study was therefore to measure the impact THA had on the PROMS in our young patients undergoing THA, to determine QoL improvement.
 
Methods: This was a prospective, consecutive cohort study of patients under the age of 17 years undergoing THA by a single surgeon in a tertiary referral centre. Patient electronic notes, radiographs and PROMS (EQ5D-Y, Oxford Hip Score (OHS) and modified Harris Hip Score (mHHS)) were reviewed.
 
Results: 12 children (8 females and 4 males) underwent THA before their 17th birthday, with 5 undergoing bilateral operations (17 THA total). The mean age was 14.6 years (10.75-16.9) and mean follow-up 1.7 years. Nine of the THA were undertaken for congenital syndromes, 4 for AVN, 2 for Perthe’s disease and 1 for dysplasia and idiopathic chondrolysis. The mean pre-operative OHS was 15 (1-33) improving to 31 (19-39) at 6-weeks, 44 (42-46) at a year and 48 (47-48) at 3 years. mHHS improved from a pre-operative mean of 25 (0-56) to 60 (37-92) at 6-weeks, 65 (38-84) at a year and 91 (91) at 3 years. The EQ-VAS mean score pre-operatively was 35 (8-100) improving at 6-weeks to 73 (55-96), 84 (76-96) at a year and 92 (76-100) at 3 years. All patients achieved MCID or higher for OHS. 6 patients were wheelchair users preop. All patients were independent walkers at follow-up. There were no complications.
 
Discussion: THA in children is safe and leads to a significant positive impact on QoL as measured with validated PROMS scores. Wheelchair users can reliably gain independent walking. Further follow-up is required understand the long-term outcomes.

Disclosure: J. Barrow: None Declared, A. Foster: None Declared, M. Kenawey: None Declared, T. Board received grant/research support from: DePuy Synthes, is consultant for: DePuy Synthes, is a paid instructor for: DePuy Synthes, has a conflict with: Royalties from Springer, Associate Editor of Hip International, Research Committee Member for BOA

There is NO Conflict of Interest: No

1761 - OUTCOME OF MENISCAL REPAIRS IN PAEDIATRIC POPULATION: A TERTIARY CENTRE EXPERIENCE

A. Gabr¹, S. Williams¹, S. Dodd¹, N. Barton-Hanson¹

¹Alder Hey Children's NHS Foundation Trust, Trauma and orthopaedics, Liverpool, United Kingdom

Background: Meniscal sparing surgery is a widely utilised treatment option for unstable meniscal tears. The aim of this study was to assess the re-operation rate and functional outcomes of meniscal repairs in children and adolescence.

Methods: We performed a retrospective review of all patients who underwent arthroscopic meniscal repair surgery between January 2007 and January 2018. All patients were under the age of 18 at the time of surgery. Procedures were all performed by a single surgeon. Information was gathered from our hospital Electronic Patient Records (EPR) system. The primary outcome measure was re-operation rate (need for further surgery on the same meniscus).

Results: We identified 59 patients who underwent 66 All-inside meniscal repairs (32 medial meniscus and 34 lateral meniscus). There were 37 males and 22 females with an average age of 14 years (range 6-16). The average follow-up time was 53 months (range 16-140). Six patients had concomitant ACL reconstruction surgery along with the meniscal repair. There were no intra-operative complications. The re-operation rate for meniscal repairs was 16.6% (11 cases) with 2 patients requiring further meniscal repairs and 9 patients underwent partial meniscectomies. The mean postoperative IKDC score was 88 (44-100), Tegner score was 7(2-10) and Lysholm score was 94 (57-100).

Conclusion: Our results showed that arthroscopic repair of meniscal tears in the paediatric population is an effective treatment option that has a low failure rate and good postoperative clinical outcomes with the advantage of preserving meniscal tissues.

There is NO Conflict of Interest: Yes

1910 - Predicting paediatric anterior cruciate ligament injury: The influence of steep lateral posterior tibial slope & its relationship to the lateral meniscus

T. Edwards¹, A.Z. Naqvi¹, N. Dela Cruz¹, C. Gupte¹

¹Imperial College London, MSk Lab, London, United Kingdom

Background: This study examines the relationship between posterior tibial slope & lateral meniscal bone angle (LMBA) on anterior cruciate ligament (ACL) tear risk in a pediatric population.

Methods: In this case-control study, non-contact, ACL-injured, pediatric patients with no significant lateral meniscal lesions were age and gender matched in a 1:1 ratio to a group of radiologically normal controls. Knee magnetic resonance imaging (MRI) studies were analysed by 2 independent, blinded observers measuring the medial posterior tibial slope (MTS), lateral posterior tibial slope (LTS) and LMBA. Sagittal slope asymmetry was calculated as the absolute difference in ° between slopes & the relationship between LMBA & LTS was calculated as a ratio. Binary logistic regressions identified independent predictors of ACL injury. Receiver operator characteristics were performed to determine predictive accuracy.

Results: 20 study patients (mean age 14.8 ± 2.42 years) were compared with 20 gender & age-matched controls (mean age 14.55 ± 2.04). LTS was significantly higher in the ACL-injured group (11.35±3.79° vs 7.04±2.65°, p =0.0002) as were the absolute slope difference (7.09±3.02° vs 3.06± 2.77°, p=0.0001) and LTS:LMBA ratio (0.47±0.18 vs 0.27±0.12, p=0.0001). No significant differences were observed for MTS or LMBA. Independent predictors were LTS (OR: 1.56 [95% CI:1.16-2.10], p=0.003), LTS:LMBA ratio (OR: 3.07 [95% CI: 1.43-6.62], p=0.004) and absolute slope difference (OR: 1.72 [95% CI: 1.20-2.46], p=0.003). Absolute slope difference and LTS:LMBA ratio were the strongest predictors (area under the curve: 0.85 & 0.87 respectively).

Conclusion: This study suggests LTS, absolute slope difference & LTS:LMBA ratio are significant pediatric ACL-injury risk factors. All three demonstrate good predictive accuracy, however sagittal slope asymmetry & the relationship between steep LTS & shallow LMBA were stronger predictors than LTS in isolation. These criteria could be used to risk-assess athletes with a view to developing injury prevention strategies.

There is NO Conflict of Interest: Yes

62 - Outcome Analysis Of Ender Nail In Paediatric Femoral Shaft Fracture

RR Akhtar¹

¹Benazir Bhutto Hospital,Rawalpindi Medical University, Rawalpindi, Pakistan

Background: Usage of spica casting as the treatment for children with femoral shaft fractures is a controversy. Operative approach is the main stand for the management of femoral shaft fractures in children presently. The advantages of flexible intramedullary nails as a fixation device are closed insertion of the device, with preservation of fracture hematoma and minimal risk of fracture site infection, no reaming is required and as such the endosteal blood supply is essentially preserved.

Objectives: To assess the treatment outcome of ender nail in paediatric femoral shaft fractures in terms of union,function and limb length discrepancy.

Study Design & Methods: This case series was done using non-probability purposive sampling technique at department of orthopedic surgery from March 2015 to October 2017. We enrolled 83 children 6 -13 years of age with fracture shaft of femur and children with skeletal dysplasia, malignancy, pathological fracture were excluded from the study. We recorded time of surgery, infection, implant failure, union, limb length discrepancy and functional outcome. Time of surgery, infection, implant failure, limb length discrepancy was recorded clinically while union and functional outcome was observed using radiographic and Flynn criteria.

Results: There were 49 (59.03%) male and 34 (40.96%) female children. Mean age was 7.89 ± 3.43 years. The mean duration of surgery was 20 ± 6.12 mins.There were 04 (4.8%) superficial and no case of deep infection. There was no implant failure. The time duration from clinical & radiographic union to full weight bearing was 7.2 weeks (5-12weeks). On Flynn criteria 57 (68.7%) has excellent and 26 (31.3%) had satisfactory functional outcome. There was no limb length discrepancy in 7 (85.8%) children with mean of 5.23mm discrepancy in 10 (14.2%) children.

Conclusions: Ender nail is a good treatment option for paediatric femoral shaft fracture in terms of union and functional outcome with low rate of infection, implant failure and limb length discrepancy.

There is NO Conflict of Interest: Yes

202 - The Inpatient Cost of Developmental Dysplasia of the Hip: Is delayed presentation more expensive?

T Walton¹, K Hughes¹, S Maripuri¹, T Crompton¹

¹Brighton and Sussex University Hospitals NHS Trust, Trauma and Orthopaedics, Brighton, United Kingdom

Background: Developmental dysplasia of the hip (DDH) can be treated using conservative management, provided diagnosis is made early. In the UK, selective screening is used to guide the need for definitive imaging and subsequent treatment. The aim of this study was to determine the total cost of inpatient admissions for DDH at a large NHS trust, and identify any association with newborn screening status on the total cost of treatment.

Methods: All inpatient episodes between 01/01/2014 to 30/06/2019 with an ICD-10 code stem of Q65 ‘congenital deformities of hip’ were retrospectively screened. Data was obtained from electronic and paper records. Patients were divided into ‘screening-positive’ (diagnosed through selective screening) and ‘screening-negative’ (not diagnosed through screening). The tariff paid for each inpatient episode was identified, and the number of individual clinic attendances, surgical procedures and radiological examinations performed (USS, XR, CT, MRI) were recorded.

Results: 41 patients were admitted for inpatient management. 44% (n=18) were screening-positive, diagnosed at mean age 6.7 weeks. 56% (n = 23) were screening-negative, diagnosed at mean age 26 months. During the study period, the total cost of inpatient care in the screening-positive group was £171,471 (£9,526.18 per-patient) compared to £306,615 (£13,331.10 per-patient) for screening-negative cases. In the screening-positive group, there were 99 clinic attendances, 47 surgical procedures and 160 radiological examinations performed (36 USS, 107 XR, 17 CT). This compared to 148 clinic attendances, 56 surgical procedures and 215 radiological examinations (187 XR, 26 CT, 2 MRI) in the screening-negative group.

Conclusion: This study demonstrates that ‘screening-negative’ patients account for a greater proportion of inpatient admissions related to DDH. They incur a higher cost from inpatient treatment per patient, and necessitate more resources. This study adds to the ongoing conversation around the cost-effectiveness of selective screening for DDH in the UK.

There is NO Conflict of Interest: Yes

263 - A retrospective review of patients treated surgically for developmental dysplasia of the hip

M Sharrock¹, C Whelton¹, Q Choudhry², R Paton²

¹School of Surgery, North West Deanery, Manchester, United Kingdom, ²Royal Blackburn Teaching Hospital, East Lancashire Hospitals NHS Trust, Blackburn, United Kingdom

Purpose: The aim of this retrospective study is to identify trends in presentation, surgical treatment and outcomes of patients with developmental dysplasia of the hip in a single centre cohort, over a 22 year period.

Methods: The available clinical records and imaging were reviewed of 106 children (117 hips) treated surgically. Demographic data, age and mode of presentation, and surgical treatments were reviewed, as well as outcomes, re-operation rate and AVN incidence. Early presentation was defined as less than 4 months to include those patients identified during the six week check.

Results: 106 children (16 male, 90 female) underwent surgery from 1997 to 2017, (79.3% Caucasian). 85 children presented with dislocation, 24 with dysplasia (3 had both dislocation and dysplasia in different hips), and 13 patients had bilateral dislocations. The mean age at presentation was 12.1 months, with 45 patients (42.5%) diagnosed early (younger than four months of age), and 61 patients presenting late (subgroup mean age for late presentation 20.9 months). After accounting for variations in birth-rate within the trust’s catchment area, there was an increasing trend in late presentation, but constant rate of early presentation. This has also been associated with an increasing trend in the operative rate per 1000 births. Of the patients requiring surgery for dislocation (n=85), 25 were reduced closed, 55 required open reduction, with 20 femoral osteotomies and 40 pelvic osteotomies. 33 (39%) patients underwent further surgery for dislocation, and 4 (4.7%) patients were diagnosed with AVN.

Conclusion: This study demonstrates an increasing trend in late presentation (> 4 months age) and surgical management, over time. This suggests that screening is failing to identify these children within a reasonable time, and therefore, increasingly aggressive surgical management is indicated.

There is NO Conflict of Interest: Yes

848 - The treatment of DDH using a Pavlik Harness – The Alder Hey Experience over >20 years

I. Jaly¹, G. Laing¹, I. Shah¹, S. Saville¹, R. Davies¹, C. Bruce¹, N. Garg¹, D. Perry¹, C. Talbot¹

¹Alder Hey Children's Hospital NHS Foundation Trust, Trauma & Orthopaedics, Liverpool, United Kingdom

Background: Use of the Pavlik harness has become the accepted first line option of initial treatment in neonates/young infants for the treatment of developmental dysplasia of the hip (DDH). We aim to describe the Alder Hey method in treating DDH in a Pavlik Harness and to present our outcomes over the last 20 years.

Method: This was a retrospective cohort study. All patients who underwent Pavlik Harness treatment for DDH using our standard treatment protocol at Alder Hey were identified. Our treatment protocol dictates immediate discontinuation of the harness on achievement of a Graf I hip, with no weaning. Following achievement of a stable Graf I hip, patients are followed up in clinic up until the age of 5 years. Those who failed treatment and required surgery were followed up until skeletal maturity. Demographics, time in harness, success rates are described. All data was collated and analysed on Excel.

Results: A total of 1392 patients were included. 18 % male, 82% female. Mean age at harness application was 52 days. Mean duration of treatment in Harness was 8.9 weeks. A total of 315 Graf IIA, 475 Graf IIB, 513 Graf IIC, 487 Graf III, 3 Graf IV were treated. 86% of our cohort were successfully treated in a Pavlik Harness.

Conclusions: Our experience of non-weaning Pavlik Harness treatment for DDH is consistent with quoted literature of success rates. It remains a safe and valuable 1st line treatment method for DDH.

There is NO Conflict of Interest: Yes

913 - The safety and efficacy of ring splints in the management of the dysplastic hip in older infants

S. McMahon¹, R. McKenna¹, A. Cosgrove¹

¹Royal Belfast Hospital for Sick Children, Belfast, United Kingdom

Introduction: We aim to assess the effectiveness and safety of ring splints in the management of the dysplastic hip in patients between 6 and 12 months of age.

Method: All infants who had full-time application of ring splints for hip dysplasia initiated between 6 and 12 months of age, with no prior treatment, between 2012 and 2016 were included. Acetabular index (AI) was measured on radiographs at the start and the end of treatment. A comparator group who had two interval radiographs, but no treatment, was identified.

Results: 186 hips (133 patients) were included. The mean age at initiation of treatment was 221 (185-347) days. The mean duration was 85.6 (55-112) days. The mean starting AI was 32.5° (30-40°) and the mean final AI was 25.3° (16-32°), with a mean change in AI of 7.2° (1-17°). Three hips (1.6%) did not tolerate treatment and four hips (2.2%) were lost to follow-up. There was one (0.5%) femoral nerve palsy leading to abandonment. No patients had AVN and three (1.6%) underwent arthrogram. One (0.5%) has persistent dysplasia requiring surveillance for a future corrective procedure. The comparator group comprised of 85 hips (52 patients). The mean age at first radiograph was 216 (184-299) days, with a mean AI of 29.4° (27-33°). The mean interval between radiographs was 91.3 (77-113) days and the mean change in AI was 2.0° (-3-12°). This was significantly less than the treated group (p=0.0001). No secondary procedures were required in this cohort.

Conclusion: Treated hips showed a greater magnitude of AI change than the comparator group. There was a high compliance rate, low complication rate and only one patient requiring a future corrective procedure.

Implications: This data suggests that ring splints are both safe and effective in treating dysplastic hips in this older cohort.

There is NO Conflict of Interest: Yes

1268 - Distal Tibial Fractures in Children: Management Remains Unclear

L. Render¹, A. Rammohun¹, D. Bodansky¹, J. Himsworth¹, N. Giannakakis¹, V. Parnami², N. Nicolaou³, V. Muthukumar², A. Christou³, D. Perry¹

¹Alder Hey Children's Hospital, Liverpool, United Kingdom, ²Royal Manchester Children's Hospital, Manchester, United Kingdom, ³Sheffield Children's Hospital, Sheffield, United Kingdom

Background: Paediatric distal tibial fracture management is diverse and optimal treatment is controversial. We present the management and outcomes in three large UK tertiary centres.
 
Method: We undertook a retrospective review of all patients with distal tibial physeal fractures, presenting to three UK paediatric trauma centres (2017-19).  

Results: Of 129 patients, median age was 12 (IQR2), with 85 males. Fractures were grouped according to Salter-Harris classification: 3 SH1;  78 SH2; 19 SH3; 29 SH4. Nine fractures were open (3 SH1, 6 SH2). 24 were excluded through inaccessible follow-up data.
All SH 1 fractures were treated with K-wires with one physeal arrest. Of 78 SH2 fractures, 33 were stable and treated conservatively with a cast, 22 with screws, 9 external fixator and 14 with K-wires. One patient with screw fixation had physeal arrest. SH2 patients treated by cast were followed-up for a median of 39 days (IQR28); K-wires 173 days (IQR87); screws 357 days (IQR199) and 622 days (IQR325) for external-fixation. Twelve SH3 patients received screws and 7 received casts.
7 of 29 SH4 patients received casts, 2 plate fixation, 18 screws and two K-wires. SH4 follow-up for casts was a median 141 days (IQR179); plate fixation 115 days; screws 309 days (IQR266) and K-wires 138 days.

Conclusion/Findings: All treatment options had low complication rates. Within unstable fractures, particularly SH2 and SH4, there is variation in treatment for similar injuries. There was no association between complications and any particular fixation method. Conservative management in stable fractures had a shorter hospital stay. K-wire fixation had a low complication rate but required later removal. Treatment choice should be influenced by cost-effectiveness, burden of total procedures and total time under orthopaedic care.

Implications: Different treatments are currently utilised in treating unstable physeal injuries, with similar complication rates. Cost-effectiveness and efficacy should be considered.

There is NO Conflict of Interest: Yes

1555 - Will it get worse? Predicting which immature hips will develop into developmental dysplasia of the hip

B. Marson¹, J. Hunter², K. Price²

¹University of Nottingham, Trauma and orthopaedics, Nottingham, United Kingdom, ²Nottingham University Hospitals, Trauma and Orthopaedics, Nottingham, United Kingdom

Background: It is unclear which children with physiologically immature hips will develop dysplasia requiring treatment, so most will be monitored with the accompanying anxiety and inconvenience for new families. The aim of this project is to identify if there are predictive features to identify which hips will develop dysplasia to help target investigations and interventions for those most at risk.

Methods: Children with risk factors or concerns from GP assessments were all assessed in a single one-stop hip clinic. Outcomes from all patients presenting to the paediatric hip clinic between 1/9/2014 and 1/10/2019 were prospectively collected. Children with immature (Graf IIa) hips were included.
Parents were advised to use double nappies, avoid swaddling and to return for a repeat scan to confirm normal development. Potential predictive covariates were analysed through logistic regression.

Results: 9,119 children were reviewed in the clinic of which 532 (5.8% of referrals) had immature hips. The mean age at first scan was 36.8 days (SD 23.7).
Thirty-nine (7.3%) of children with immature hips subsequently developed dysplasia including four children with Graf III and 2 children with Graf IV hips. All children that developed dysplasia were successfully treated using a Pavlik harness.
Breech presentation, family history, clicky hip, CETV, limited abduction or leg length discrepancy and time of first scan (within 28 or 42 days) were not significant predictors of dysplasia. Half of the children who developed Graf III of IV hips were referred with a dislocatable hip (HR for all DDH 7.6 95% CI 3.2-18.7).

Conclusions: Immature hips are a common finding during hip screening and can be treated in the majority with minimal intervention. Children with dislocatable hips at birth should be observed closely, though the sensitivity of 23% is low. We therefore recommend repeat ultrasound to confirm hip stability and avoidance of dysplasia.

There is NO Conflict of Interest: Yes

1766 - Ultrasound follow-up after successful treatment in Pavlik harness for Developmental Dysplasia of the Hip. Seven years’ experience from a paediatric tertiary referral centre

K. Studnicka¹, E. Spink¹, C. Talbot¹

¹Alder Hey Children's Hospital, Liverpool, United Kingdom

Introduction: A national newborn screening aims to recognise Developmental Dysplasia of the Hip (DDH) at the earliest possible stage where treatment with Pavlik harness is most successful. Apart from ultrasound (USS) monitoring of hip development in harness, we perform USS four weeks after successfully completed treatment.

Aims: To verify if the 4 week USS follow-up has influence on treatment.

Methods: Patients with DDH hips IIc-IV according to Graf, successfully treated with Pavlik harness between 2012 and 2019 identified. Babies who failed harness treatment were excluded. Details of referral, surgical treatment, and follow-up obtained from electronic notes. USS reports and radiological follow-up images reviewed on PACS.

Results: Majority of 342 babies referred from Maternity Unit with dislocatable hip. The average waiting time for the first appointment was 35 days (0-67).
USS performed on the day of Pavlik harness application identified 161 right and 273 left Graf IIc-IV hips. Treatment lasted on average for 60 days (29-149). On removal of the harness, the average alpha angle in either hip was 64°. 76 % of babies had USS follow-up showing average left and right hip’s alpha angle of 63° (57-75; 54-72). The average age on the most recent follow up was 44 months (2-86) with an acetabular index of 20° and 22°.
Despite Graf I hip at the time of removal of the harness, two hips regressed to IIb on follow-up scan. Both were followed up radiologically and didn’t require surgical treatment. Four hips with normal parameters on follow-up scan were found subluxed on subsequent radiographs and required surgical treatment.

Conclusion: USS surveillance during the period in Pavlik harness is an excellent adjunct in monitoring the treatment and filtering the cases requiring surgical intervention. The 4 weeks follow-up hasn’t influenced the surgical management of monitored hips and will be discontinued.

There is NO Conflict of Interest: No

157 - Application of E3 method (educate, engange and empathesize) enhances the patient satisfaction after TKR

A. Doshi¹, S. Londhe²

¹Meril Life Sciences, Orthopaedics, Mumbai, India, ²Holy Spirit Hospital, Orthopaedics, Mumbai, India

Introduction: TKR is the most successful operation in modern day orthopedics. Still about 20-30% remain dissatisfied with the operation. Various factors like sex, BMI have been studied for their effect on the patient satisfaction. In this study we employed a counsellor to educate,engage and provide empathy to the patient undergoing TKR. The counselling started preoperatively and continued throughout the perioperative period upto six months post operatively. We started the study with null hypothesis.

Material and Methods: 100 patients were divided into group A and group B. Both the groups were matched for age, sex, BMI, coexistent co-morbidities. Group B received preoperative counselling by the surgeon whilst group A received counselling by the counsellor in the preoperative, perioperative and post operative period (at 1 week, 2 week, 4 week, 8 week, 16 week and 24 weeks post operatively). The counsellor educated the patient about the TKR procedure, the modalities of pain management and the post operative ambulation programme. The counsellor was trained to alleviate the the patient fears and reassure the patient on the course of recovery. At 24 weeks after the operation patient satisfaction and consumer gap was recorded by an independent observer.

Results: The patient satisfaction with the TKR procedure was significantly better with group A than group B (88% with group A versus 74% with group B). Consumer gap was present only in 6 % of patients in group A as against 16% of patients in group B. This difference is statistically significant. P value 0.005

Conclusion: This study clearly demonstrates that the use of counsellor for the patient undergoing TKR in the preoperative, peri operative and post operative period significantlly improves the patient satisfaction scores and reduces the consumer gap. Hence we strongly advocate the employment of a trained counsellor for the patients undergoing TKR procedure in the pre operative, peri operative and post operative period.

There is NO Conflict of Interest: Yes

204 - Peri-operative administration of tranexamic acid in lower limb arthroplasty: a multicentre, prospective cohort study

T. Lloyd^1,2,3, G. Neal-Smith², J. Fennelly², H. Claireaux^2,1, C. Bretherton^2,1, A. Carr¹, M. Murphy³, B. Kendrick^4,1, A.J.R. Palmer¹

¹University of Oxford, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Science, Oxford, United Kingdom, ²Oxord Surgical Collaborative for Audit and Research (OxSCAR), Oxford, United Kingdom, ³NHS Blood and Transplant, Oxford, United Kingdom, ⁴Oxford University Hospitals NHS Trust, Department of Orthopaedics, Oxford, United Kingdom

Introduction: Tranexamic acid is recommended for all surgery where expected blood loss exceeds 500mls. However, the optimal dose, route and timing of administration is not known. This study aimed to evaluate current practice of peri-operative tranexamic acid administration in patients undergoing primary hip and knee arthroplasty in the UK.

Methods: Patients undergoing primary total hip arthroplasty, total knee arthroplasty or unicompartmental knee arthroplasty during a two-week period were eligible for inclusion in this prospective study. The primary outcome was the proportion of patients receiving tranexamic acid in the peri-operative period. Secondary outcomes included: dose, route, and timing of tranexamic acid administration, prevalence of pre- and postoperative anaemia, estimated blood loss and red blood cell transfusion rates. Regional variation in practice was explored by country, with England sub-divided into Public Health England regions.

Results: 1701 patients were recruited from 56 NHS hospitals. 1523/1701 (89.5%) patients received tranexamic acid, of these 1052/1523 (69.1%) received a single dose of 1g intravenously either pre- or intra-operatively. 571/1701 (33.6%) and 1386/1701 (81.5%) patients were anaemic (Hb<130g.l-1) in the pre- and postoperative period, respectively. Mean (SD) estimated blood loss for all included patients was 792(453) ml and 54 patients (3.1%) received a red blood cell transfusion postoperatively. The lowest rate of preoperative anaemia was in North East England (22.0%) and the highest rate was recorded in Yorkshire and Humber (49.5%). Blood transfusion rates were lowest in Northern Ireland (0%) and highest in Yorkshire and Humber (7.6%).

Conclusions/Findings: Current standard of care in the UK is to administer 1g of tranexamic intravenously either pre- or intra-operatively. Approximately one-third of patients present for surgery with anaemia, although the overall red blood cell transfusion rate is low.

Implications: These data provide useful comparators when assessing the efficacy of tranexamic acid and other patient blood management interventions in future studies.

There is NO Conflict of Interest: Yes

381 - Can introducing a hyponatremia protocol with a direct endoctine pathway help reduce hyponatremia in elective knee and hip replacement patients? A closed loop audit and service evaluation study

M Waller¹, M Hampton¹, T Harrison¹, J Stoddard¹

¹Sheffield Teaching Hospitals Trust, Orthopaedics, Sheffield, United Kingdom

Background: Hyponatremia has a prevalence of up to 30% after orthopaedic surgery(1) and is associated with poor outcomes postoperatively, including mortality of up to 20%(2) and longer stay(1).
This study assessed the prevalence of hyponatremia following total hip & knee replacement (THR & TKR), the causes identified, further tests and management, effect on length of stay, ICU admission and the impact of an endocrinology agreed hyponatremia protocol.
 
Methods: Post-op U&E's for patients undergoing elective TKR/THR replacement were reviewed. Retrospective data was gathered through ICE. Parameters included demographics, procedure, sodium pre and post op, Endocrine input, HDU admissions and length of stay.
A hyponatremia protocol based on NICE guidance was then developed and agreed with STHT's endocrinology department and a second audit cycle was initiated. SPSS software was used for data analysis.
 
Results: Hyponatraemia was found in 12% of patients, resulted in a significantly longer stay (7.7 days vs 4.6t=-4.6p=<0.00001) and multiple critical care admissions (8 ICU days). It was more common in TKR (X2=5.5194P=0.018807) and older age (t=-2.81083p=0.002619). Prior to implementation of the endocrine pathway it was under investigated(38%), and in both cycles the precipitating factors such as age and use of diuretics corroborated with prior research(3,1).
 
Conclusion/Findings: Implementation of the hyponatremia protocol resulted in quicker referrals to Endocrinology (2.3vs3.6 days), reduced the length of stay by almost a day(t=-2.40973p=0.008144) and reduced the number of ICU days to 0(X2=4.6189p=0.031622).
 
Implications: This endocrine pathway is easily reproducible should other departments also wish to trial it. It may help reduce waiting times and improve outcomes for TKR/THR’s within the NHS.

Disclosure: This study was based within one unit in STHT limiting its relevance to the wider population and audit cycles only assessed patients over four-month periods limiting reliability.

There is NO Conflict of Interest: Yes

593 - The right thing to do: “Showing Acts of Kindness”. The Torbay experience of improving departmental morale

A. Roberton¹, R. Ramesh¹

¹Torbay Hospital, Trauma and Orthopaedics, Torquay, United Kingdom

Background: Progressing from Medical Student to Junior Doctor can be overwhelming and stressful.  Burnout can affect 1 in 3 Junior Doctors and has significant implications for their quality of life, workforce retention and patient care.  The GMC National Trainee Survey (NTS) identified “lack of support” as a reason for low morale in our hospital.  The Boorman review recognises that an organisational culture is required for effective change to improve staff wellbeing. This is our strategy.
 
Methods: We have introduced the philosophy of “Showing Acts of Kindness”.  This started as a process where Junior Doctors were enabled to “buddy-up” with colleagues and had prescribed Acts of Kindness such as coffee rounds, checking-in phone calls and regular meetings.  The philosophy has grown to encompass many of the common features of a positive work environment identified by Health Education England. Specifically, good rota management, regular teaching including daily “Pearls-of-Wisdom”, a 4pm on-call meeting, feedback meetings and creation of a WhatsApp group. 
 
Results: Successive GMC NTS suggest Junior Doctors in our department feel valued, supported and enjoy their placement.  Significant improvement was demonstrated in; Supportive Environment (67.69% to 81.11%), Adequacy of Experience(71.21% to 90.00%), Local Teaching (46.81% to 84.78%) and Overall Satisfaction (70.63% to 88.83%).  Junior colleagues feel confident to bring up concerns and there is a stronger sense of “team”, which has been eroded since moving away from “Firm” structures.
 
Conclusion: A departmental philosophy of kindness is a powerful tool to improve Junior Doctor morale. Since introduction the Registrar feedback has also demonstrated the placement to be well regarded and popular. The Covid crisis further highlights the stress Junior Doctors face and the importance of support measures. Campaigns such as “Showing Acts of Kindness” are critical for this and have a positive impact on retention, recruitment and patient care.

There is NO Conflict of Interest: Yes

792 - Multi-Disciplinary Service Improvement to Improve Imaging Access for Suspected Cauda Equina

P. Mahapatra¹, P. Beak¹, E. Chew¹, M. Hindawi¹, I. Gill¹

¹Kingston Hospital NHS Foundation Trust, Trauma and Orthopaedics, London, United Kingdom

Background: The GIRFT Spinal services report and SBNS/BASS Standards of care set out a clear path for investigation of suspected cauda equina syndrome (CES). The ENTICE Audit demonstrated a significant burden of out-of-hours referrals to specialist centres, substantial costs of transferring patients, and staffing difficulty within MRI departments. Working together, we agreed a local protocol for MRI investigation of suspected CES in conjunction with radiology and radiography departments to allow rapid early scanning of suspected CES patients, including out-of-hours facilities.

Methods: Retrospective collection of data from pre- and post-implementation of new suspected CES MRI protocol. We included all patients over 18 presenting with atraumatic back pain who underwent an MRI for investigation of CES. Data collected over a 2-month period included timings of presentation, scanning, transfer and/or discharge.

Results: Thirty-five patients were eligible for inclusion across the 2-month period. We observed an average reduction of over 5 hours (pre 14.1, post 8.4) from orthopaedic review to MRI performed. We also observed a significant reduction (pre 41.1, post 25.6, p=0.06) in hours between MRI performed and discharge. Of those patients who were transferred for scans post-implementation, 60% required subsequent surgical intervention.

Conclusion/Findings: Information available from GIRFT, SBNS/BASS and ENTICE can be used to justify development of local pathways for MRI investigation of suspected CES within district general hospital (DGH) settings. The new protocol enabled earlier scanning and discharge. This has positive implications both clinically for the patient and financially for the hospital.

Implications: DGHs should review their current practice for investigation suspected CES and if required design/revise protocol to ensure clear pathway for 24-hour MRI is available. Ideally with local adjustment to enable provision of appropriately trained radiographers out-of-hours.

There is NO Conflict of Interest: Yes

986 - Has the Getting It Right First Time (GIRFT) programme made an impact in litigation? A review of clinical negligence claims against orthopaedic surgery in England 2007/2008 to 2011/12 and 2013/14 to 2017/18

J. Machin¹, J. Hardman², C. Deacon¹, D. Ferguson³, D. Foward¹, T. Briggs⁴

¹Nottingham University Hospitals NHS Trust, Trauma & Orthopaedic Surgery, Nottingham, United Kingdom, ²Whittington Health NHS Trust, London, United Kingdom, ³Barts Health NHS Trust, London, United Kingdom, ⁴Royal National Orthopaedic Hospital NHS Trust, London, United Kingdom

Introduction: Orthopaedics has historically had the highest annual volume of claims compared to other specialties. In response to this the GIRFT litigation workstream was set up in 2012 to review claims and provide guidance on how to learn from claims to improve patient care and reduce claim volume.
Methods: A data sharing agreement was set up between GIRFT and NHS Resolution to access data regarding all claims involving orthopaedic surgery between April 2007 and April 2018. This included claim status, clinical details, and cost breakdown. A predetermined protocol was used to classify claims by orthopaedic surgeons through a claim by claim review to provide a clinical analysis.

Results: After the initial orthopaedic GIRFT visits in 2013/14 a fall in claim volume was observed over a four year period with claim numbers starting at 1617 in 2013/14 and falling to 1202 in 2017/18. The year on year fall in claims volume during this period was 6.06%, 8.76%, 9.02% and 4.68% respectively. There were an estimated 264 fewer orthopaedic claims than would have been expected.

Conclusions: In the context of the national clinical negligence bill increasing significantly orthopaedics has bucked the trend with annual costs remaining below 2013/14 levels for the years reviewed. The positive change in orthopaedics in comparison to other specialties has resulted in the specialty falling from its historical top ranking in claims volume to second behind emergency medicine with a respective fall in its share of clinical negligence costs from 10% in 2013/14 to 4% in 2017/18. Correlation between any one factor and litigation trends is not directly possible however it seems apparent that notifying clinicians of claims to facilitate and ensure learning from the incidents behind them must contribute to the improvement of patient care and limits the risk of future litigation.

There is NO Conflict of Interest: Yes

1145 - Reducing the duration of post-operative antibiotics in surgical prophylaxis for lower limb arthroplasty is safe; results of a quality improvement project

T. Okoro¹, M. Wan², T. Mukabeta³, E. Malev⁴, C. Williams⁴, M. Gross⁴, P. Craig⁴, J. Murnaghan⁴

¹Robert Jones and Agnes Hunt Orthopaedic Hospital NHS Foundation Trust, Arthroplasty, Oswestry, United Kingdom, ²Unity Health Toronto, Pharmacy, Toronto, Canada, ³Royal Devon and Exeter Hospital, Exeter Hip Unit, Exeter, United Kingdom, ⁴Sunnybrook Holland Orthopaedic and Arthritic Center, Toronto, Canada

Background: This quality improvement (QI) study assessed the impact of a reduction in the number of doses administered in the prophylactic antibiotic regimen for lower limb arthroplasty (primary total hip and knee arthroplasty (THA/TKA)) at a tertiary referral centre.

Methods: Following Ethical approval, a QI project was undertaken at the busiest arthroplasty unit in Canada (~ 2400 operations/year). Multidisciplinary meetings were held with various stakeholders prior to the change. The previous regime ((PR); September 2018 - December 2018) of a single pre-operative dose (cefazolin 2g intravenously (IV)), and two subsequent antibiotic doses (cefazolin 2g IV at 2 hours and cefazolin 1g IV at 8 hours), was compared to the new regime ((NR); January to April 2019) i.e. a weight-based pre-operative dose (cefazolin 2g IV for patients <120kg; cefazolin 3g IV for patients >120kg) and a single subsequent dose (cefazolin 2g IV at 2 hours). The primary outcome was surgical site infection (SSI) incidence at 12-month follow-up. 

Results: A total of n=1273 operations (THA n=534, TKA n= 739) were performed over the study period in n=1264 patients (males n=493, females n= 771).  For the PR group (n=669;) the mean age was 69.3 ±11.9 years, whilst for the NR group (n= 595) the mean age was 68.8 ±10.5 years. There was no statistically significant difference in deep incisional infection rate between the PR and NR groups (0.74% (5/675) vs. 0.66% (4/598); fishers exact test p=1.00), nor in the superficial incisional infection rate (PR 2.07% (14/675) vs. NR 1.50% (9/598); fishers exact test p= 0.53) at 12 months following surgery. 

Conclusions: Reducing the number of post-operative antibiotic doses had no adverse impact on SSI incidence, at 12 months following surgery, in this patient population. 

Implications: Use of a weight-based regime, with reduced duration, for antibiotic prophylaxis is safe in lower limb arthroplasty.

There is NO Conflict of Interest: Yes

1197 - The importance of early MRI in the diagnosis of acute occult scaphoid fractures: an audit of MRI waiting times and diagnostic results in a Major Trauma Centre

R.L. Donovan¹, E. Lostis¹, A. Bott¹, N. Blewitt¹, M.B. Kelly¹

¹North Bristol NHS Trust, Trauma & Orthopaedic Surgery, Bristol, United Kingdom

Introduction: Magnetic Resonance Imaging (MRI) is considered the ‘gold standard’ for the investigation of suspected occult scaphoid fractures. In May 2018, 68% of surgeons attending the British Society for Surgery of the Hand (BSSH) Conference reported that an ‘MRI Scaphoid’ could be completed within 2 weeks of request at their institutions. Our study aimed to audit MRI waiting times for the investigation of acute occult scaphoid fractures at our institution against a BSSH members consensus timeframe, and to evaluate the clinical importance of early scanning in patients with wrist trauma and persistent symptoms despite normal radiographs.

Methods: We conducted a retrospective audit of all MRI requests investigating suspected occult scaphoid between February and August 2019 at our regional Major Trauma Centre. Waiting times, from request to scan, and their results were reviewed to assess the pickup rate of occult fracture and other significant diagnoses. MRI requests for atraumatic causes or chronic conditions were excluded.

Results: We analysed 200 MRI Wrist requests over six months. 134 patients met the inclusion criteria. The mean time-to-MRI was 20.8 days. Four patients (3%) underwent same-day MRIs, 26 patients (19%) had an MRI within 7 days, and 84 patients (63%) achieved MRI within 14 days. Early imaging with MRI detected acute occult scaphoid fractures in 16 patients (12%) and high rates other non-scaphoid related injuries.

Conclusions: We confirm in our trust, the value of MRI as an early diagnostic tool in occult scaphoid fractures. However, a third of patients wait longer than 2 weeks for their investigation. We, therefore, suggest that national standards of care in regard to scaphoid fractures may help hospitals develop efficient MDT pathways for these potentially complex injuries.

There is NO Conflict of Interest: Yes

1330 - Torbay Charts as an efficient Patient Decision Aid (PDA) in the management of hip and knee arthritis

R. Ramesh¹

¹Torbay Hospital, Department of Trauma & Orthopaedics, Paignton, United Kingdom

Background: To make an informed decision in collaboration (Shared Decision Making - SDM), one requires enthusiastic clinicians, willing patients, and a good information repository like Patient Decision Aids (PDA). Surgical rates decrease by a minimum of 11.5% (Sepucha et al, 2017) when PDA are used. Current PDA have unattractive, cumbersome layouts and can be impractical during consultations. NICE recognises the limitations of the current PDA (June 2020). Torbay Charts (TC) PDA has a novel infographic overview of disease progression where treatment options are listed to the stage of the disease and provide a focal point during SDM conversation. Web-version allows the users to have a side-by-side comparison of risks, benefits, burden, and costs with links to a video library.

Methods: Our objective was to evaluate TC to enable SDM. Pilot testing was conducted over an 8-week period and was focused on the management of hip and knee arthritis (107 patients). Additional testing was conducted at a different hospital (14 patients). Thus, 121 patients used TC to reach a collaborative decision. The outcome was evaluated with a questionnaire.

Result: 92% strongly agreed that TC helped their SDM process. 91% strongly agreed they understood various treatment options. Healthcare practitioners felt they had an engaging consultation with TC’s focused approach. 13.2% chose non-operative treatment. 7.4% of patients who came expecting surgery opted for conservative treatments.

Conclusion: TC multi-layer, multi-formatted approach addresses many of the limitations of current PDAs. In 8w of its trial a potential cost avoidance of a minimum £45,000 was achieved with 7.4% choosing non-operative methods. Using NJR data, with a conservative 2% surgery avoidance, over £26 million per year could be potentially saved.

Implications: TC revolutionary approach enhances SDM, saves money, and allows a “Montgomery compliant” choice exercise for patients before choosing the most appropriate personalised cost-effective treatment.