Introduction. LIMB-Q Kids is a new patient-reported outcome measure (PROM) for children with Lower limb differences (LLDs). The objective is to conduct an international field test study. Materials & Methods. A mixed method multiphase approach was used to develop LIMB-Q Kids. In phase one, a systematic review was conducted to identify concepts from existing PROMs used in research with children with LLDs. A preliminary conceptual framework derived from the systematic review informed an international qualitative study. The data from qualitative interviews were used to form the LIMB-Q Kids, which was further refined through multiple rounds of cognitive debriefing interviews with children. Input was obtained from parents and healthcare professionals from Australia, Canada, Ethiopia, India, UK, and the USA. LIMB-Q Kids was translated and culturally adapted into multiple languages. Results. The final field-test version consists of 11 scales (159 items) that measure appearance, physical function, symptoms (hip, knee, ankle, foot, and leg), leg-related distress, and school, social and psychological function. This version was rigorously translated into Danish and German. Translations that are in progress include Arabic, Finnish, Hindi, Swahili, Portuguese, Spanish, and Luganda. An international field-test study is underway in nine countries (15 sites with a target recruitment of 150 participants per country). At the time of abstract submission, 190 patients from seven sites have completed LIMB-Q Kids. The UK collaborative has worked on language adaption for the UK and is currently validating the score across five paediatric limb reconstruction units. Conclusions. No internationally applicable PROM exists for children with LLDs. We present the current progress in developing and validating such a score. Data from the international field-test study will be used to reduce items and perform psychometric testing of LIMB-Q Kids. The rigorous translation and cultural adaption process will provide versions of LIMB-Q Kids in different languages. Once completed, the LIMB-Q Kids will provide a common metric for outcome assessment for children with lower limb differences internationally

Increased collection of patient-reported outcome measures (PROM) in registries enables international comparison of patient-centered outcomes after knee and hip replacement. We aimed to investigate 1) variations in PROM improvement, 2) the possible confounding factor of BMI, and 3) differences in comorbidity distributions between registries. Registries affiliated with the International Society of Arthroplasty Registries (ISAR) or OECD membership countries were invited to report aggregate EQ-5D, OKS, OHS, HOOS-PS and KOOS-PS values. Eligible patients underwent primary total, unilateral knee or hip replacement for osteoarthritis within three years and had completed PROMs preoperatively and either 6 or 12 months postoperatively, excluding patients with subsequent revisions. For each PROM cohort, Chi-square tests were performed for BMI distributions across registries and 12 predefined PROM strata (male/female, age 20-64/65-74/>75, high or low preoperative PROM scores). Comorbidity distributions were reported for available comorbidity indexes. Thirteen registries from 9 countries contributed data, n~130000 knee (range 140 to 79848) and n~113000 hip (range 137 to 85281). Mean EQ-5D index values (10 registries) ranged from 0.53 to 0.71 (knee) and 0.50 to 0.70 (hips) preoperatively and 0.78 to 0.85 (knee) and 0.83 to 0.87 (hip) postoperatively. Mean OKS (6 registries) ranged from 19.3 to 23.6 preoperatively and 36.2 to 41.2 postoperatively. Mean OHS (7 registries) ranged from 18.0 to 23.2 preoperatively and 39.8 to 44.2 postoperatively. Four registries reported KOOS-PS and three reported HOOS-PS. Proportions of patients with BMI >30 ranged from 35 to 62% (10 knee registries) and 16 to 43% (11 hip registries). For both knee and hip registries, distributions of patients across six BMI categories differed significantly among registries (p30 were for patients in the youngest age groups (20 to 64 and 65 to 74 years) with the lowest baseline scores. Additionally, females with lowest preoperative PROM scores had highest BMI. These findings were echoed for the OHS and OKS cohorts. Proportions of patients with ASA scores ≥3 ranged from 7 to 42% (9 knee registries) and 6 to 35% (8 hip registries). PROM-score improvement varies between international registries, which may be partially explained by differences in age, sex and preoperative scores. BMI and comorbidity may be relevant to adjust for

Given the low prevalence of sarcoma, international cooperation is necessary to recruit sufficient numbers of patients for surgical trials. The PARITY (Prophylactic Antibiotic Regimens in Tumour Surgery) trial is the first international multicentre trial in orthopedic oncology and successfully achieved target enrollment of 600 patients across 12 countries. It is important to reflect upon the challenges encountered and experiences gained to inform future trials. The objective of this study is to describe recruitment patterns and examine the differences in enrollment across different PARITY sites and identify variables associated with varying levels of recruitment. Data from this study was obtained from the PARITY trial Methods Centre and correspondence data. We performed descriptive statistics to demonstrate the recruitment patterns over time. We compared recruitment, time to set up, and time to enroll the first patient between North American and international sites, and sites that had dedicated research personnel. Two-tailed non-paired t-tests were performed to compare average monthly recruitment rates between groups with significance being set at alpha=0.05. A total of 600 patients from 48 clinical sites and 12 countries were recruited from January 2013 through to October 2019. Average monthly enrollment increased every year of the study. There were 36 North American and 12 international sites. North American sites were able to set up significantly faster than international sites (19.3 vs. 28.3 months p=0.037). However, international sites had a significantly higher recruitment rate per month once active (0.2/month vs. 0.62/month, p=0.018). Of active sites, 40 (83%) had research support personnel and 8 (17%) sites did not. Sites with research personnel were able to reach ‘enrolment ready’ status significantly faster than sites without research support (19.6 vs. 30.7 months, p=0.032). However, there was no significant difference in recruitment rate per month once the sites began enrolling (0.28/month vs. 0.2/month, p=0.63). Trial sites that took longer than 1 year to recruit their first patient had 3x lower average recruitment rate compared to sites that were able to recruit their first patient within a year of being enrolment ready. The PARITY trial is the first multicentre RCT in orthopaedic oncology. The PARITY investigators were able to increase the recruitment levels throughout the trial and generally avoid trial fatigue. This was a North American based trial which may explain the longer start up times internationally given the different regulatory bodies associated with drug-related trials. However, international sites should be considered critical as they were able to recruit significantly more patients per month once active. The absence of research support personnel should not preclude a site from inclusion. These sites took longer to setup but had no difference in monthly recruitment once active. This study will create a framework for identifying and targeting high yield sites for future randomized control trials within orthopaedic oncology to maximum recruitment and resource allocation. Data quality is another consideration that will be addressed in future analyses of the PARITY trial

The Canadian Institute for Health Information (CIHI) and the Organisation for Economic Co-operation and Development (OECD) have partnered to advance international patient-reported outcome measures (PROMs) collection and reporting standards for hip and knee arthroplasty. This project is part of the OECD's Patient-Reported Indicator Survey (PaRIS) initiative, which aims to address the need for internationally comparable patient-reported outcome and experience measures in order to better monitor health system performance and drive continuous improvement. PROMs are in varying stages of implementation across OECD health systems, with differences in collection and reporting practices across existing programs. CIHI and the OECD are leading an international working group for PROMs in hip and knee replacement surgery in order to build consensus on PROMs data collection standards and develop indicators for international reporting. Working group members include patient representatives, clinicians, national arthroplasty registries, the International Society of Arthroplasty Registries (ISAR), experts in PROMs measurement, and government representatives of several OECD member countries. Activities of the working group focus on two main priorities: 1) Use existing PROMs programs to maximize pilot comparable reporting in OECD's Health at a Glance 2019 report, and 2) Advance new PROMs standards and data collection to maximize comparable reporting beyond Health at a Glance 2019. An environmental scan of PROMs in hip and knee arthroplasty found that a number of countries are collecting this data, however, there are variations in survey instruments as well as administration and reporting methods within and across countries. As part of priority 1, the working group has achieved consensus on a number of aspects around pilot reporting. The project is compiling data from existing PROMs programs in order to report results in the Health at a Glance 2019 publication. For priority 2, the most notable challenge is establishing an agreement across countries on common survey tools, as well as a minimum data set that works for all, given the disparities of existing collection across countries. Many international programs lack the flexibility to change PROMs tools or collections methods, and have concerns regarding the break in trend for PROMs data within their own countries if they were to change methods. The project is exploring the use of crosswalks and other opportunities for comparable reporting, such as the use of single-item anchor questions. To date, the working group continues to develop consensus on international standards for PROMs collection and reporting. Results of the international consensus building and work to date will be shared. PROMs incorporate the patient's perspective into the delivery of treatments and care – such as hip and knee arthroplasty – that aim to improve a patient's quality of life. Alignment of standards in PROMs collection across countries will make comparable data available for reporting, in order to inform quality improvement initiatives within health systems to provide better care for patients. CIHI and the OECD will continue to work with member countries to develop international data collection and reporting standards for PROMs, and encourage the adoption of common approaches across countries

Aim. Deep infection following endoprosthetic replacement (EPR) of long bones is a devastating complication occurring in 15% of musculoskeletal tumour patients. The recently published PARITY Trial demonstrated that extending antibiotic prophylaxis from 24 hours to 5 days does not reduce infection rates. However, questions remain about the optimal antibiotic choice and dose. Method. A 23-question multiple-choice questionnaire was designed and piloted through an iterative feedback process until the final version was agreed by all authors. Open and closed-ended questions were used to gather information on practice and Likert-type scale responses were used to grade responses to ascertain surgeon perceptions and preferences. The online survey was sent to all surgeon delegates of the 34th Annual Meeting of the European Musculo-Skeletal Oncology Society in London in October 2022. Results. Amongst 61 respondents, 43 were based in Europe and 18 outside of Europe. The majority (48/61) had been in clinical practice over 11 years. Antibiotic choice. 1st or 2nd generation cephalosporins were the first line choice practiced among 49 (80.3%) of respondents. Of these, 39 responded had a 2nd line protocol for beta-lactam allergy which was most commonly clindamycin (18), vancomycin (11) or a combination of a glycopeptide or clindamycin plus gentamicin (4). Respondents changed their first line regimen for radiotherapy in 6/61, chemotherapy in 8/61 and tumour site in 20/61. Re-dosing. Intraoperative re-dosing intervals of 1st and 2nd generation cephalosporins ranged from 2 to 8 hourly. Re-dosing for blood loss ranged from never to when 2 litres was lost. Of the 47 respondents, 24 said intraoperative re-dosing is always reliably administered. Duration. Six (10%) of 61 respondent routinely cover the intraoperative period only, whereas 30 (49%) give 24 hours, 16 (give 48 hours or longer and 8 continue until surgical drains are removed. 31 of 61 change duration depending on clinical situation. The most common reasons for changing were patient risk factors, soft tissue status and previous radiotherapy. 57/61 surgeons were aware of the PARITY Trial. When these respondents were asked whether they had changed practice based on PARITY, 12 said yes, 24 said no and 21 said they always give 24 hours anyway. Conclusions. Amongst an international cohort of orthopaedic oncology surgeons there was a wide variation in practice. Further research should focus on the optimum choice and re-dosing strategy, which have not been defined

Excessive postoperative opioid prescribing is a significant contributor to the opioid crisis. Prescribing in orthopaedic surgery is often further complicated by high use of opioid-based preoperative analgesia. ‘Opioid PrEscRiptions and usage After Surgery’ (OPERAS) is an international multicentre prospective student- and trainee-led collaborative study which aims to quantify the amount of opioids prescribed at discharge after common orthopaedic surgeries against what is consumed by patients at 7-days, and assess the impact of opioids on patient-reported outcomes. Data is being collected over 6 14-day periods on consecutive adult patients undergoing shoulder arthroplasty, rotator cuff repair, shoulder labral repair, anterior cruciate ligament repair, hip arthroplasty, and knee arthroplasty, with follow-up via telephone call at 7-days after discharge. The primary outcome is the proportion of oral morphine equivalents (OME) of prescribed opioids versus consumed opioids at 7-days post-discharge. This ongoing study is actively recruiting in over 20 countries. Globally, 65 centres are collecting orthopaedic, including 10 New Zealand centres and 17 Australian centres. To date, 284 orthopaedic patients have been prospectively enrolled with complete data (mean age 59.6 ± 16.7 years; 51.6% female). Overall, 77% and 89% of patients were prescribed opioids on discharge in New Zealand and Australia respectively. On average, 60% of prescribed opioids were consumed at 7-days post-discharge globally (150 OME (75-500) vs. 90 OME (15-200); p<0.01). In New Zealand and Australia, 42.1% (285 OME (150-584) vs. 120 OME (6-210); p<0.01) and 63.3% (150 OME (86-503) vs. 95 OME (28-221); p<0.01) of prescribed opioids were consumed at 7-days, respectively. OPERAS will provide the first high-quality global data on opioid prescription and consumption patterns with patient perspectives. These data can inform prescribing practice and inform guidelines. The growing interest in New Zealand and Australia in student- and trainee-led orthopaedic collaborative research, as evidenced by this study should be actively encouraged and fostered

Aim. Suppressive antimicrobial therapy (SAT) is used worldwide for patients with a prosthetic joint infection (PJI but clear definitions or guidelines regarding the indications, antimicrobial strategy or treatment duration are currently lacking in the literature. The aim of this study was to identify the global differences in the clinical practice of SAT for PJI. Method. An online survey was designed to investigate the current opinion on indication and treatment goals, preferred antimicrobial drugs, dosing and treatment duration and follow-up of patients with PJI on suppression. The survey was distributed using e-mail lists of several international bone and joint infection societies and study groups. Recipients were asked to share the survey with colleagues who were not a member of one of the societies but who were involved in PJI care. Results. The questionnaire was fully completed by 330 physicians from 43 different countries on six continents (Europe, n=134, 41%; Oceania n=112, 34%; North America, n=51, 16%; other, n=33, 10%; total response rate 14%). Antimicrobial treatment for PJI was discussed in a multidisciplinary team in Europe (90%), Oceania (42%) and North America (12%). In six of eight (75%) different clinical scenarios, respondents from North America would most often place a patient on SAT. In seven of eight (88%) scenarios, SAT was started least often by European respondents. The presence of a fistula was considered a contra-indication for suppression by 74 respondents (22%). First choices of SAT for staphylococcal PJI were: oral cephalosporins (39%) and tetracyclines (31%) in North America; anti-staphylococcal penicillins (55%) and oral cephalosporins (24%) in Oceania; tetracyclines (27%) and anti-staphylococcal penicillins (22%) in Europe. For streptococcal PJI, most clinicians preferred penicillins (91% in Oceania, 67% in Europe, and 53% in North America). Preferred SAT for gram negative PJI was: fluoroquinolones and a penicillin/betalactamase inhibitor in North America (26% and 18%, respectively) and Oceania (23% and 27%, respectively); fluoroquinolones (31%) and Cotrimoxazole (28%) in Europe. The dosage of SAT was never lowered (n=126, 38%), standardly lowered for all antibiotics (n=79, 24%) or only lowered for specific antibiotics (n=125, 38%). SAT was prescribed for an indefinite duration (n=43, 13%), as fixed duration between six months and three years (n=104, 32%) or for an undetermined prespecified duration (n=154, 47%). Conclusions. Substantial variation in the practice of SAT for PJI exists between physicians worldwide and throughout the different continents. This reflects the paucity of data regarding the indication and treatment of PJI with SAT

Introduction. In January 2000, the Bone and Joint Decade was formally launched at the headquarters of the World Health Organization in Geneva, Switzerland. The goal was “to improve the health-related quality of life for people with musculoskeletal disorders throughout the world”. They aimed to do this, in part, by “raising awareness of the growing burden of musculoskeletal disorders on society”. The Bone and Joint Decade has 63 supporting governments, over 700 supporting government and non-government organisations and a budget in the millions. It was the largest musculoskeletal health promotion campaign in history. Aim. To determine the impact of the Bone and Joint Decade on the International Press. Methods. LexisNexisTM Professional search engine utilised to retrieve articles from all known English language national newspapers internationally containing the term “Bone and/& Joint Decade” from January 1999 to January 2010. Results. Only 56 articles were found from the all the worlds English language national newspapers. These came from 13 countries; only 2 were part of the EU. Australia mentioned it most- 12 times in 10 years. The Bone & Joint Decade was the main topic of the article in only 23%. In only 48% was the role of the Bone and Joint Decade mentioned- in 20% of these its role was incorrectly quoted. In only 23% was someone from the organisation quoted and in only 27% was a medical professional quoted. The portrayal of the Bone and Joint Decade was of a neutral tone-93%, positive tone-2% and a negative tone-5%. Conclusions. The Bone and Joint Decade has ended and very few were made aware that it started. The media coverage of the largest musculoskeletal health campaign in history has been woefully inadequate

Background. Standard preoperative protocols in total joint arthroplasty utilize the International Normalized Ratio (INR) to determine patient coagulation profiles. However, the relevance of preoperative INR values in joint arthroplasty remains controversial. Acceptable INR cutoff values for joint replacement are inconsistent, and are often based on studies of primary arthroplasty, or even non-orthopedic procedures. This analysis examined the relationship between preoperative INR values and post-operative outcomes in revision total hip arthroplasty (rTHA). Optimal cutoff INR values correlated with specific outcomes were subsequently determined. Methods. The American College of Surgeons National Surgical Quality Improvement Program (NSQIP) was retrospectively queried for revision total hip arthroplasty procedures performed between 2006 and 2017. Patients with a preoperative INR collected no later than 1 day prior to surgery were further stratified for analysis. INR values which correlated with specific outcomes were determined using receiver operating characteristics (ROC) curves for each outcome of interest. The optimal cutoff INR value for each outcome was then obtained using univariate and multivariate models which determined INR values that maximized both sensitivity and specificity. Results. There were a total of 11,393 patients who underwent a revision total hip arthroplasty from 2006–2017 recorded in NSQIP. Of the 2,012 patients who met inclusion and exclusion criteria, 858 had an INR < 1.0, 931 had an INR > 1.0 to 1.25, 175 had an INR > 1.25 to 1.5, and 48 patients had an INR > 1.5. Patients with progressively higher INR values had a significantly different risk of mortality within 30 days (p=0.005), bleeding requiring transfusion (p< 0.001), sepsis (p=0.002), stroke (p<0.001), failure to wean from ventilator within 48 hours (p=0.001), readmission (p=0.01), and hospital length of stay (p< 0.001). Similar results were obtained when utilizing optimal INR cutoff values. When correcting for other factors, the following poor outcomes were significantly associated with the respective INR cutoff values (Estimate, 95% CI, p value): LOS (1.67, 1.34–2.08, p <0.001), bleeding requiring transfusion (1.65, 1.30–2.09, p<0.001), sepsis (2.15, 1.11–4.17, p 0.02), and any infection (1.82, 1.01–3.29, p 0.04). Conclusions. INR values >1.65, >1.67, >1.82, and >2.15 were correlated with increased transfusion requirements, LOS, any infection, and sepsis respectively. Therefore, even subtherapeutic elevations in INR may predict poor outcomes following revision total joint replacement. Surgeons and perioperative medical specialists should consider more stringent INR goals when optimizing patients prior to revision arthroplasty. Level of Evidence. Prognostic Level IV. For any figures or tables, please contact authors directly

Introduction. The number of young and more active patients requiring total knee replacement (TKR) is increasing. Preclinical evaluation and understanding the long-term failure of TKR is therefore important. Preclinical wear simulation of TKR is usually performed according to the International Standards Organization (ISO) recommendations. Two international standards for preclinical wear simulation of TKRs have been developed so that the anterior-posterior (AP) translation and internal-external (IE) rotation can be driven in either force or displacement control. However, the effects of using different control regimes on the kinematics and wear of the same TKR have not been investigated. The current study investigated the kinematics, contact mechanics and wear performance of a TKR when running under ISO force and displacement control standards using an experimentally validated computational model. Materials/Methods. Three different ISO control standards were investigated using a size C Sigma curved TKR (DePuy, UK), with moderately cross-linked UHMWPE curved inserts; ISO-14243-3-2004, ISO-14243-3-2014 and ISO- 14243-1-2009. Axial force and flexion-extension angle are common for the three standards. AP and IE motions are displacement controlled in ISO-14243-3-2004 and ISO-14243-3-2014, with the only difference being a reversal of AP polarity between the two standards, and are force controlled in ISO-14243-1-2009. The test setup and soft tissue constraints were defined in accordance with ISO recommendations. The wear model was based on the modification of Archard's law where the wear volume is defined as a function of contact area, sliding distance, cross-shear and contact stress. The simulation framework has been independently validated against experimental wear rates under three different standard and highly demanding daily activities (Abdelgaied et al. 2018). Results. Reversing AP in the displacement control ISO-2014, compared to ISO-2004, resulted in high contact stresses of more than 70 MPa in the posterior direction. The predicted AP and IE from the force control ISO-2009 were in different directions and magnitudes to ISO-2014 AP and IE. The predicted wear rates were 1.8, 2.0, and 5.5 [mm. 3. /mc] for ISO-14243-3-2004, ISO-14243-3-2014 and ISO-14243-1-2009 respectively. Discussion. Reversing AP in the displacement control ISO-2014, without revising the femoral centre of rotation, resulted in high stress edge loading in the posterior direction, due to femoral rollback, and more than 10% increase in wear rate compared to ISO-2004. The predicted AP and IE from the force control ISO-2009 had different polarities and magnitudes to the corresponding displacement control ISO-2014 AP and IE. In addition, the predicted wear rate under the force control ISO-2009 was more than double that measured under displacement control standards due to the increased AP and IE motions predicted under the force control standard. In addition to the previous validation of the model, the predicted wear rate under the force control ISO-2009 of 5.5 mm. 3. /mc was within the 95% confidence limits of the reported experimental wear rate for the same TKR of 4.71±1.29 mm. 3. /mc (Johnston et al. 2018) which gives more confidence in the model. Conclusion. The study showed significant differences between ISO force and displacement control standards and between ISO displacement standards with different AP polarities. These differences should therefore be considered when choosing a control regime for preclinical simulation of TKR

Background. In the late 1980's Michael Freeman conceived the idea that knee replacement would most closely replicate the natural knee joint, if the medial Tibio-Femoral articulation was configured as a “ball-in-socket”. Over the last three decades, medial rotation and medial pivot designs have proved successful in clinical use. Freeman's final iteration of the medial ball-in-socket concept was the Medial Sphere knee. We report the three-year survivorship, clinical outcomes, patient reported outcome measures (PROMs) and radiographic analysis of this implant in a multi-centre, multi-surgeon, prospective observational study. Methods. Patients awaiting total knee replacement were recruited by four centres. They had no medical contraindication to surgery, were able to provide informed consent and were available for follow-up. Primary outcome was implant survival at six months, one, two, three and five years. Secondary outcomes were patient reported outcome measures: Oxford Knee Score (OKS), Euroqol (EQ-5D), International Knee Society Score (IKSS), IKSS Functional score and Health State score, complications and radiographic outcomes. Radiographic analysis was undertaken using the TraumaCad software and data analysis was undertaken using SPSS. Results. To date, 328 female and 202 male patients with a mean age 66.9 years and mean body mass index 30.0 were recruited. Three year Kaplan-Meier survivorship analysis of cumulative failure showed an implant survival of 99.46% (95% confidence interval 100 – 96.74), when deaths and withdrawals were treated as censored data. Twelve patients withdrew (2.26%), seven died (1.32%) and two knees were revised (0.38%). The mean EQ5D, Health State Scores, OKS, IKSS & IKSS Function scores at three years improved significantly from pre- operative scores (Health State Score: 9.91 (65.59 pre-op to 75.50); OKS: 18.82 (19.90 pre-op to 38.72); IKSS: 39.87 (44.39 pre-op to 92.09); IKSS Function Score: 35.03 (49.42 pre-op to 84.45). The mean improvement of EQ5D at three years was: 0.34 (0.48 pre-op to 0.82). Discussion. Survival of the GMK Sphere to three years in this study was over 99%. Risk of revision compares favourably with UK National Joint Registry (NJR) data. The improvements that are seen in patient reported outcome measures reflect an enhancement in patient function and quality of life. Conclusion. At three years follow-up, the implant demonstrates satisfactory survival and outcomes. Patient matching and evaluation of more cases, at more time points will allow outcome comparison with other implant options

Aim

Prosthetic joint infection (PJI) due to Candida spp. is a severe complication of arthroplasty but is little reported. This study describes Candida PJI epidemiology, management, and outcome.

Introduction. Patellar resurfacing is performed in more than 90% of primary total knee arthroplasties (TKAs) in the United States, yet far fewer patellae are resurfaced internationally. Multiple randomized controlled trials have shown decreased revision rates in patients with resurfaced patellas (RP) vs. non-resurfaced (NR). However, most of these studies showed no difference in patient satisfaction, anterior knee pain, or knee society scores. (Figure 1) Given uncertain benefits, the purpose of this study was to determine if the rates of patellar resurfacing have changed over the past 10 years worldwide. Methods. Data was obtained via direct correspondence with registry administrators or abstracted from the annual reports of six national joint registries: Australia, Denmark, England, New Zealand, Norway, and Sweden. Rates of patellar resurfacing between 2003 and 2013 were collected. Where data was available, subgroup analysis was performed to examine revision rates among RP and NR TKAs. Results. The average rates of patellar resurfacing from 2003 to 2013 ranged from 5% (Norway) to 71% (Denmark). Three countries showed a decreased rate of patellar resurfacing over this time period while two demonstrated an increase. The largest decrease in resurfacing rates was in Sweden (15% to 2%), while the biggest increase was in Australia (44% to 53%). (Figure 2) In 2010, 48,367 of 137,813 (35%) primary TKAs from all six countries were resurfaced. (Figure 3) Among RP and NR TKAs, Australia documented a 10-year cumulative revision rate (CRR) of 4.9% and 6.0%, respectively. Sweden showed a 10-year CRR of 4% in both groups. Conclusion. While not all national joint registries report rates of patellar resurfacing, it is clear that most countries outside of the US continue to resurface a much smaller proportion of patellas in primary TKA. Worldwide, the rates of patellar resurfacing have changed little in the past decade

Orthopaedic International Medical Graduates (IMGs) have provided an invaluable service and source of workforce relief mainly in rural and outback Australia. Queensland has relied more heavily than any other state on overseas trained doctors to provide general practitioners and specialists around the state, particularly in areas deemed ‘an area of need’ (AON). The AON designation was seen to be a way of easy recruitment but is a two-edged sword for both the state government and for the IMG. While overseas trained doctors may be more compliant with administrators' wishes than what locally trained doctors might be, they have not necessarily passed a local medical examination or even sat a medical examination in English before coming to Australia. Meticulous and drawn out medical qualification checks, health and security checks are carried out which can take a long time to perform and could frustrate the end user who is often dependent on that doctor arriving by a certain date to cover a call roster and maintain a continuum of care for a specific district. The many and varied steps have been changing over the past few years and so this presentation is meant to clear up some of the misunderstandings that exist for the various parties involved. This would include some guidelines to the IMG and to the recipient hospital or practice recruiting that IMG, outlining some of the traps and pitfalls for all to consider. State government administrators also need to show leadership when advertising, interviewing and employing IMGs, as this may have implications for all of us into the next decade. A frank look at our present and future workforce needs by the whole Orthopaedic community is necessary. The challenges and solutions of how Orthopaedic Surgery will be provided both publically and privately into the future is resting with us now

Aim. Gram negative bacteria (GNB) are emerging pathogens in chronic post-traumatic osteomyelitis. However, data on multi-drug (MDR) and extensively drug resistant (XDR) GNB are sparse. Methods. A multi-centre epidemiological study was performed in 10 countries by members of the ESGIAI (ESCMID Study Group on Implant Associated Infections). Osteosynthesis-associated osteomyelitis (OAO) of the lower extremities and MDR/XDR GNB were defined according to international guidelines. Data from 2000 to 2015 on demographics, clinical features, microbiology, surgical treatment and antimicrobial therapy were retrospectively analyzed. Cure was assessed after the end of treatment as the absence of any sign relevant to OAO. Factors associated with cure were evaluated by regression analysis. Results. A total of 53 infections of OAO of the lower extremities (hip, femur, tibia) were evaluated. Patients were female (n=32, 60.4%), with a mean age (SD) 57(3) years, history of trauma (83%), comorbidities (26.4%). The most frequent GNB were: E.coli (n=15), P.aeruginosa (n=14), Klebsiella spp (n=8), Enterobacter spp (n=8) and Acinetobacter spp (n=5). P.aeruginosa predominated the XDR group than the MDR one (n=6/10 vs n=8/43, p=0.01). Antibiotics were given mostly in combinations (64%) for a median duration of 117 days (SD:31.5). Carbapenems were the most frequently used agents (54.7%), followed by colistin (18.8%) and fluoroquinolones (15%). Surgical treatment included debridement with implant retention (n=22), implant explantation (n=22), new osteosynthesis (n=3), others(n=6). Only failure of the surgical treatment for OAO was associated with lack of cure [OR 8.924 (CI95%: 3.006–26.495), p<0.001] at the end of treatment, for a 12-month follow-up period. Patients' age, gender, comorbidities, history of trauma and surgery, clinical presentation of OAO, type of antimicrobial treatment (use of fluoroquinolones, carbapenems or colistin as monotherapy or in combination) as well as type of surgical intervention (explantation vs implant retention) were not found to significantly influence the patients' outcome. Overall, cure was assessed in 31 patients (58.5%). Death occurred in 7 patients, all older than 60, with failure of surgical treatment (p=0.016). These patients presented with many comorbidities (57%) and without difference in treatment outcome between XDR and MDR infection (p=0.114). Conclusion. Osteosynthesis-associated infections of the lower extremities caused by MDR/XDR GNB are a severe complication in orthopaedic surgery. The role of surgical treatment is independently associated with outcome regardless of the type of intervention (explantation or implant retention) and the type of antimicrobial treatment

Aim

It is unclear if the prevalence of resistance organisms causing (PJI) in total hip/knee arthroplasty is different among North/South American and European countries. Therefore, we sought to compare causative organisms, rates of resistant organisms, and polymicrobial infections in hospitals in North/South America, and Europe.

Femoroacetabular impingement (FAI) is a common cause of hip pain in the young adult. Uncertainty regarding surgical indications, outcome assessment, management preferences and perceptions of the literature exist. We conducted a large international survey assessing the perceptions and demographics of orthopaedic surgeons regarding FAI. A survey was developed using previous literature, focus groups and a sample-to-redundancy strategy. The survey contained forty-six questions and was emailed to national orthopaedic associations and orthopaedic sports medicine societies for member responses. Members were contacted on multiple occasions to increase response rates. Nine hundred orthopaedic surgeons from twenty national and international organisations completed the survey. Surgeons responded across 6 continents, 58.2 % from developed nations with 35.4 % having sports fellowship training. North American and European surgeons reported significantly greater exposure to hip arthroscopy during residency and fellowships in comparison to international respondents (48.0% vs. 44.5% vs. 25.6% respectively; p<0.001). Surgeons performing a higher volume of FAI surgery (over 100 cases per year) were significantly more likely to have practiced for more than 20 years (OR 1.91; 95% CI 1.01 to 3.63), be practicing at an academic hospital (OR 2.25; 95% CI 1.22 to 4.15), and have formal arthroscopy training (OR 46.17; 95% CI 20.28 to 105.15). High volume surgeons were over two-fold more likely to practice in North America and Europe (OR 2.26; 95% CI: 1.08 to 4.72). The exponential rise in the diagnosis and surgical management for FAI appears to be driven largely by experienced surgeons in developed nations. Our analysis suggests that although FAI management is early in the innovation cycle we are at a tipping point towards wider uptake and utilisation. The results of this survey will help guide further research and study

Generic walking profiles applied to mechanical knee simulators are the gold standard in wear testing of total knee replacements (TKRs). Recently, there was a change in the international standard (ISO) for knee wear testing (ISO 14243-3): the direction of motion in the anterior/posterior (AP) and internal/external (IE) directions were reversed. The effects of this change have not been investigated, therefore it is not known whether results generated by following this new standard can be compared to historical wear tests which used the old standard. Using a finite element analysis (FEA) model of a TKR in parallel with an energy based wear model and adaptive remeshing, we investigated differences in wear between the newest ISO standard developed in 2014, and the previous ISO standard developed in 2004. CAD models of a left sided NexGen Cruciate Retaining (CR) TKR (Zimmer, Warsaw, IN) were used to create the FEA model (Figure 1). The loads and motions specified by simulator standards ISO 14243-3(2004) and ISO 14243-3(2014) were applied to the model. Analyses were run using ABAQUS v6.13-2 Standard (Dassault Systèmes, Waltham, MA). 8 node hexahedral elements were used to model the UHMWPE component. The contact was modeled as penalty contact, with the friction coefficient set to 0.04 on the articular surface. The cobalt chromium molybdenum femoral component was modeled as a rigid surface, utilizing a mix of 2. nd. order quadrilaterals and tetrahedrons. Wear of the polyethylene (PE) component was predicted to 1,000,000 cycles using a previously published frictional energy-based wear model. The wear model, developed from data generated in wheel-on-flat tests, utilizes two parameters defining the frictional energy required to remove a unit volume of material both parallel (3.86E8 J/mm. 3. ) and perpendicular (3.55E7 J/mm. 3. ) to the primary polyethylene fibril direction. Primary fibril direction for the analysis was set to the AP direction. Wear for each simulation of a gait cycle was scaled to 500,000 cycles. Two gait cycles were simulated representing 1,000,000 cycles in total. Adaptive remeshing was driven by the wear model, with the mesh being updated every time increment to simulate material ablation. The time step size was variable with a maximum of 0.01s. The FEA predicted higher wear rates for the newest ISO standard (7.34mg/million cycles) compared to the previous standard (6.04mg/million cycles) (Figure 2). Comparing the predicted wear scars (Figure 3), the new version of the standard covered a larger percentage of the total articular surface, with wear being more spread out as opposed to localized. This is more similar to what is seen in patient retrievals. The results of the study suggest that major differences between the old and the new ISO standard exist and therefore historical wear results are not comparable to newly obtained results. In addition, this study demonstrates the utility of FEA in wear analysis, though the wear model needs further work and validation before it can be used as a supplement to simulator testing. Validation of the wear model against simulator tests and pin-on-disk experiments is currently underway. For figures/tables, please contact authors directly.

Background. Vertebral body compression fractures (VCFs) impair quality of life (QOL) and increase patient morbidity and mortality. The international, multicentre, randomised, controlled Fracture Reduction Evaluation (FREE) trial was initiated to compare effectiveness and safety of Balloon kyphoplasty (BKP) to non-surgical management (NSM) for the treatment of acute painful VCFs. We describe the primary endpoint of the ongoing 2-year study. Methods. Patients with 1-3 non-traumatic VCFs (< 3 months old) were randomised to either BKP or NSM. The primary endpoint was the change in QOL as measured by the SF-36 Health Survey Physical Component Summary (PCS) at one month, and device/procedure-related safety. Secondary endpoints included SF-36 subscales, the EQ-5D, self-reported back pain and function using the Roland Morris Disability Questionnaire (RMDQ). All patients were given osteoporosis medical therapy. Results. Among the BKP (N=149) and NSM (N=151) cohorts, mean patient age was 73 years and 77% were female. Most patients had VCFs due to primary osteoporosis; 8 patients due to corticosteroid-induced osteoporosis, and 4 had cancer-related fractures. Thirty-nine BKP (26%) and 36 NSM (24%) patients had >1 VCF treated. At one month follow-up, the mean improvement in the PCS was in favour of BKP over NSM (p<0.0001). All physical component SF-36 subscales and the total EQ-5D score were significantly improved for BKP compared to NSM. Mean improvements in back pain at 7 days and 1 month were significantly greater for BKP compared to NSM (p<0.0001 at both time points). The improvement in RMDQ for BKP over NSM was also significant (p<0.0001). There was one soft tissue haematoma and urinary tract infection, with no bone cement-related serious adverse events. Conclusions. Compared to non-surgical management, balloon kyphoplasty demonstrated superior short-term pain, function and quality of life outcomes with no difference in serious adverse events for the treatment of acute, painful vertebral compression fractures. (Clinical trials.gov number, NCT00211211)

To compare 24-month patient-reported outcomes after surgical treatment or casting in patients age 60 years of age or older with unstable distal radius fractures (DRF's).

The Wrist and Radius Injury Surgical Trial (WRIST), is the largest randomized, multicenter trial in Hand Surgery, which enrolled 304 adults with isolated, unstable DRF's at 24 institutions. WRIST participants were followed for 24 months- longest follow-up among prospective studies comparing four treatment methods. Patients who agreed to surgical treatment (n=187) were randomized to internal fixation with volar plate (VLPS), external fixation, or percutaneous pinning; patients who preferred conservative management (n=117) received casting. The primary outcome was 24-month Michigan Hand Outcomes Questionnaire (MHQ) Summary score. Secondary outcomes were MHQ Domain scores.

At 24-month assessment, participants' mean MHQ Summary score was 86 (95% CI: 83,88), representing good hand function. Participants reported good return of their Activities of Daily Living (ADLs) with a mean MHQ ADL score of 88 (95% CI: 85,91). Finally, participants were satisfied, with a mean MHQ Satisfaction score of 84 (95% CI: 80,88). There were no significant differences in score by treatment group in any MHQ domain at 24 months. Six weeks after surgery, VLPS participants scored significantly higher than the other three groups on (ADLs) and Satisfaction (both p<0.0001), whereas participants who received external fixation scored significantly lower than the casting and VLPS groups on the same domains. By the 3-month assessment, the gap between VLPS and casting had disappeared but external fixation participants continued to report significantly worse scores. External fixation participants did not report comparable ADL scores to the other three groups until 12 months after surgery.

Participants reported good outcomes 24 months after DRF regardless of treatment. Casting and VLPS are both acceptable treatments for older adults. The decision between the two treatments should be made considering patient goals regarding recovery speed and desire to avoid surgical risks. External fixation should be avoided because of worse outcomes in the year after surgery and the risk of pin site infections.