Background. Periprosthetic joint infection (PJI) following total knee arthroplasty (TKA) is a severe complication in terms of disability, morbidity, and cost. We performed a study to investigate whether early PJI (within 90 days of primary TKA) is associated with increased mortality. Secondary aims were to compare mortality rates over time and between surgical treatment methods. Methods. Patients with suspected PJI were identified by linkage of the Swedish Knee Arthroplasty Register (SKAR) and the Swedish Prescribed Drug Register (SPDR) in 2007–2008 and 2012–2013. Medical records of patients receiving more than 4 weeks of continuous antibiotic therapy were subsequently reviewed to verify the PJI diagnosis. Information on mortality was obtained through the SKAR which is updated daily from the tax agency and patients with PJI were compared to patients without PJI. Results. 466 patients were diagnosed with PJI within 90 days and compared to 40,362 patients without PJI. Mortality rates were significantly higher for PJI patients in both short- and long term: 2.6% vs. 0.8% at 1 year, 4.9% vs. 1.9% at 2 years, 15.7% vs. 7.1% at 5 years, and 38% vs. 21.4% at 10 years. The difference in mortality rate remained after adjusting for sex, age, diagnosis, and time period for surgery with Hazard Ratio 1.8 (95% CI:1.6–2.1). Mortality rates did not differ between time periods, and we found no correlation to surgical treatment. Conclusion. Patients with early PJI after primary TKA have an increased mortality rate compared to TKA patients without PJI. Improvements in surgical treatment strategy has not resulted in better survival. Long term difference in mortality rates indicates that PJI is not the sole reason for mortality suggesting a general frailty in PJI patients

Immigrated Canadians make up approximately 20% of the total population in Canada, and 30% of the population in Ontario. Despite universal health coverage and an equal prevalence of severe arthritis in immigrants relative to non-immigrants, the former may be underrepresented amongst arthroplasty recipients secondary to challenges navigating the healthcare system. The primary aim of this study was to determine if utilization of arthroplasty differs between immigrant populations and persons born in Canada. The secondary aim was to determine differences in outcomes following total hip and knee arthroplasty (THA and TKA, respectively). This is a retrospective population-based cohort study using health administrative databases. All patients aged ≥18 in Ontario who underwent their first primary elective THA or TKA between 2002 and 2016 were identified. Immigration status for each patient was identified via linkage to the ‘Immigration, Refugee and Citizenship Canada’ database. Outcomes included all-cause and septic revision surgery within 12-months, dislocation (for THA) and total post-operative case cost and were compared between groups. Cochrane-Armitage Test for Trend was utilized to determine if the uptake of arthroplasty by immigrants changed over time. There was a total of 186,528 TKA recipients and 116,472 THA recipients identified over the study period. Of these, 10,193 (5.5%) and 3,165 (2.7%) were immigrants, respectively. The largest proportion of immigrants were from the Asia and Pacific region for those undergoing TKA (54.0%) and Europe for THA recipients (53.4%). There was no difference in the rate of all-cause revision or septic revision at 12 months between groups undergoing TKA (p=0.864, p=0.585) or THA (p=0.527, p=0.397), respectively. There was also no difference in the rate of dislocations between immigrants and people born in Canada (p=0.765, respectively). Despite having similar complication rates and costs, immigrants represent a significantly smaller proportion of joint replacement recipients than they represent in the general population in Ontario. These results suggest significant underutilization of surgical management for arthritis among Canada's immigrant populations. Initiatives to improve access to total joint arthroplasty are warranted

In the Unites States, approximately 24% of people undergoing primary total knee or total hip arthroplasty (TKA, THA) are chronic opioid users pre-operatively. Few studies have examined the incidence of opioid use prior to TKA/THA and whether it predicts outcomes post-surgery in the Australian context. The aim was to determine: (i) the proportion of TKA and THA patients who use opioids regularly (daily) pre-surgery; (ii) if opioid use pre-surgery predicts (a) complication and readmission rates to 6-months post-surgery, (b) patient-reported outcomes to 6-months post-surgery. A retrospective cohort study was undertaken utilising linked individual patient-level data from two independent databases comprising approximately 3500 people. Patients had surgery between January 2013 and June 2018, inclusive at Fairfield and Bowral Hospitals. Following data linkage, analysis was completed on 1185 study participants (64% female, 69% TKA, mean age 67 (9.9)). 30% were using regular opioids pre-operatively. Unadjusted analyses resulted in the following rates in those who . were. vs . were not. using opioids pre-operatively (respectively); acute adverse events (39.1% vs 38.6%), acute significant adverse events (5.3% vs 5.7%), late adverse events: (6.9% vs 6.6%), total significant adverse events: (12.5% vs 12.4%), discharge to inpatient rehab (86.4% vs 88.6%), length of hospital stay (5.9 (3.0) vs 5.6 (3.0) days), 6-month post-op Oxford Score (38.8 (8.9) vs 39.5 (7.9)), 6 months post-op EQ-VAS (71.7 (20.2) vs 76.7 (18.2), p<0.001), success post-op described as “much better” (80.2% vs 81.3%). Adjusted regression analyses controlling for multiple co-variates indicated no significant association between pre-op opioid use and adverse events/patient-reported outcomes. Pre-operative opioid use was high amongst this Australian arthroplasty cohort and was not associated with increased risk of adverse events post-operatively. Further research is needed in assessing the relationship between the amount of pre-op opioid use and the risk of post-operative adverse events

Dual mobility (DM) is an established bearing option in Total Hip Arthroplasty (THA). The traditional mono-block DM designs have limited ability for additional fixation, whereas the modular DM designs allow additional screw fixation but limit internal diameter and have the potential to generate metal debris. We report the early results of a CoCrMo alloy mono-block implant manufactured by additive technology with a highly porous ingrowth surface to enhance primary fixation and osseointegration. Prospective follow-up of the Duplex. TM. implant first inserted in March 2016 enrolled into Beyond Compliance (BC). Primary outcome measure was all-cause revision and secondary outcomes dislocation, peri-prosthetic fracture (PPF) and Oxford Hip Score (OHS). Patients were risk stratified and all considered to be high risk for instability. Complications were identified via hospital records, clinical coding linkage using national database and via BC website. 159 implants in 154 patients with a mean age 74.0 years and a maximum F/U of 7 years. Survivorship for all-cause revision 99.4% (95% CI 96.2–99.8). One femoral only revision. Mean gain in OHS 27.4. Dislocation rate 0.6% with a single event. Patients with a cemented Polished taper stem (PTS) had a Type B PPF rate of 2.1% requiring revision/fixation. Compared to conventional THA this cohort was significantly older (74.0 vs 68.3 years), more co-morbidity (ASA 3 46.5% vs 14.4%) and more non-OA indications (32.4% vs 8.5%). Every patient had at least one risk factor for falling and >50% of cohort had 4 or more risk factors using NICE tool. We believe our results demonstrate that risk stratification successfully aids implant selection to prevent dislocation in high-risk patients. This novel design has provided excellent early results in a challenging cohort where individuals are very different to the “average” THA patient. NJR data on DM has reported an increase in revision for PPF. A “perfect storm” maybe created using DM in high-risk falls risk population. This re-enforces the need to consider all patient and implant factors when deciding bearing selection

Aim. Infections represent a serious threat to the successful utilization of implants in modern medicine. Implant-associated infections are difficult to treat, because they involve biofilms that protect bacteria from the immune system and harbour antibiotic-tolerant persister cells. In this work, we developed an antibody-drug conjugate (ADC) containing the anti-neoplastic drug mitomycin C (MMC) as a novel treatment paradigm for implant-associated infections. MMC was chosen as it is a potent antimicrobial against biofilms and its synthesis into an ADC was chosen to alleviate toxicity. Following development and synthesis of the ADC, stability and release of MMC was measured. We then used the ADC to kill bacteria in suspension and in biofilms, in vitro and in vivo. Method. Mitomycin C was conjugated to a commercially available antibody against S. aureus via a disulfide linkage, with a drug release occurred via thiol-disulfide exchange. ADC as tested against S. aureus under various growth conditions (planktonic, persisters and biofilm). In vitro toxicity of ADC vs MMC was measured using a human cell line (MOLT-4). Finally, two independent in vivo experiments were performed in a murine implant-associated osteomyelitis model. In experiment one ADC treatment was compared NaCl, vancomycin and vancomycin + ADC (n=10 for all groups). Subsequently, ADC was compared to NaCl, the antibody used in the ADC construction, MMC and a novel ADC constructed with a non-S. aureus antibody (n=10 for all groups). All treatments were started day 7 post inoculation and were administered for 3 days. CFU enumeration was done following sonication to quantify bacterial load. Results. Drug release could be triggered on demand with N-acetyl cysteine and release occurred, once in contact with free thiols on S. aureus cell surface. The ADCs exhibited a concentration-dependent antimicrobial effect against S. aureus with doses exceeding 0.5 mg/l reducing amount of CFU to below detection limit (p< 0.001). 15 minutes exposure to ADC resulted in an approx. 2 log CFU/ml reduction compared to untreated biofilms (p < 0.01). In vivo ADC treatment was effective compared to NaCl treatment and the vancomycin treatment (p≤ 0.001). Further ADC and MMC treatment were comparable in efficacy, but both were superior than NaCl, pure antibody and the non-specific ADC (p≤ 0.05). Finally, in vitro cytotoxicity was significantly lower for ADC than MMC. Conclusions. In this study we have demonstrated that ADCs can be a novel treatment approach to combat implant-associated infections caused by S. aureus

INTRODUCTION. Since the recall of some metal on metal (MoM) THR bearings, surgeons have seen patients with pain, elevated Co and Cr levels and adverse local tissue reactions (ALTR). While many variables may contribute to THR MoM failures, many times these variables are not present in patients who present with symptoms. We investigate the possible genetic predilection of a group of patients who were revised after MoM THR surgery for pain, high Co/Cr levels and ALTR. METHODS. IRB approval was obtained prior to our study. We have analyzed 19 control (asymptomatic MoM THR patients > 6 years after surgery) and 19 disease (revised MoM THR for high metal ions and ALTR). The 38 sample intensity files were subject to sample Quality Control (QC) using Contrast QC (< 0.4) with an Affymetrix Genotyping Console. The resulting 38 sample files with genotype calls were loaded and further analyzed using the Association Workflow in Partek Genomics Suite 6.6 (Partek, Missouri). Hardy-Weinberg equilibrium test was performed on the single nucleotide polymorphism (SNP) level. The difference between the observed and expected frequencies of each allele at each locus were tested by Fisher's exact test and χ2 test. To get the working SNP list, two filters were used: (1) a SNP no-call rate should be less than 5%, and (2) minor allele frequency of a SNP should be greater than 5%. After filtering, association analysis of the SNPS with disease was done using Chi. 2. Test. In this study, χ. 2. statistic was used to assess the difference in allele frequencies between the control and disease samples. The value of χ2 statistic, degrees of freedom, and the associated p-value for each SNP were calculated. Dot Plot was used to visualize the genotypes of all samples. To measure the non-random association of alleles at different loci, Linkage Disequilibrium analysis was performed using the neighborhood size of 20 and statistic r. 2. The resulting correlations show the value of r. 2. for SNPs. The r. 2. = 1 means that two SNPs are tightly associated. RESULTS. We found that several SNPs are linked to the revision disease group that showed evidence of metal sensitivity. Among them, a strong association in the disease group was found in a SNP called MS1. In the disease group 17/19 patients were either heterozygous or recessive homozygous for MS1, with 17/19 asymptomatic patients were of the homozygous dominant MS1 isoform. Based on the Linkage Disequilibrum analysis results, several other SNPs were also fund to be strongly correlated with the disease group (Fig 1). The controls had an average Co level of 2.4 and Cr level of 1.3 while the disease group 18 and 10.4 respectively. CONCLUSIONS. This study found a strong genetic relationship in a gene we designate as MS1 where the homozygous recessive and heterozygous isoform genotypes were found in the disease group of revised MoM THRs. A strong correlation of several SNPs was also found. This may be a good predictor of failures and an avenue for personalized choice of implants in the future. For figures/tables, please contact authors directly.

Currently 180 days is the target maximum wait time set by all Canadian provinces for elective joint replacement surgery. In Nova Scotia however, only 34% of Total Knee Arthroplasties (TKA) and 51% of Total Hip Arthroplasties (THA) met this benchmark in 2017. Surgery performed later in the natural history of disease is shown to have significant impact on pain, function and Health related Quality of Life at the time of surgery and potentially affect post-operative outcomes. The aim of this study is to describe the association between wait time and acute hospital Length of Stay (LOS) during elective hip and knee arthroplasty in province of Nova Scotia. Secondarily we aim to describe risk factors associated with variations in LOS. Data from Patient Access Registry Nova Scotia (PAR-NS) was linked to the hospital Discharge Access Database (DAD) for primary hip and knee arthroplasty spanning 2009 to 2017. There were 23,727 DAD observations and 21,329 PARNS observations identified. Observations were excluded based on missing variables, missing linkages, revision status and emergency cases. Percentage difference in LOS, risk factors and outcomes were analyzed using Poisson regression for those waiting more than 180 days compared to those waiting equal or less than 180 days. For primary TKA, 11,833 observations were identified with mean age of 66 years, mean wait time of 348 days and mean LOS of 3.6 days. After adjusting for controls, patients waiting more than 180 days for elective TKA have a 2.5% longer acute care LOS (p < 0.028). Risk factors identified for prolonged LOS are advanced age, female gender, higher surgical priority indicator, required blood transfusion, dementia, peptic ulcer disease, cerebrovascular disease, heart failure, chronic kidney disease, malignancy, ischemic heart disease and diabetes. Factors associated with decreased LOS are surgical year, use of local anesthetic, peripheral location of hospital and admission to hospital from home. For primary THA, 6626 observations were identified with mean age of 66 years, mean wait time of 267 days and mean LOS of 4 days. Patients waiting more than 180 days for THA did not show a statistically significant association with LOS. Risk factors and protective factors are the same with exception of CVD and use of local anesthetic. Our findings suggest a positive and statistically significant association for patients waiting more than 180 days for TKA and longer acute care LOS. Longer LOS may be due to deteriorating health status while placed on a surgical waitlist and may represent a delayed and indirect cost to the patient and the healthcare system. Ultimately with projected increase in demand for elective joint replacement surgeries, our findings are aimed to inform physicians and policy makers in management of surgical waitlist efficiency and cost effectiveness. For any reader inquiries, please contact . shahriar-s@hotmail.com

Introduction. Total Elbow Arthroplasty (TEA) is recognized as an effective treatment solution for patients with rheumatoid arthritis or for traumatic conditions. Current total elbow devices can be divided into linked or unlinked design. The first design usually presents a linking element (i.e. an axle) to link together the ulnar and humeral components to stabilize the joint; the second one does not present any linkage and the stability is provided by both intrinsic design constraints and the soft tissues. Convertible modular solutions allow for an intraoperative decision to link or unlink the prosthesis; the modular connections introduce however additional risks in terms of both mechanical strength and potential fatigue and fretting phenomena that may arise not only due to low demand activities loads, but also high demand (HD) ones that could be even more detrimental. The aim of this study was to assess the strength of the modular connection between the axle and the ulnar component in a novel convertible elbow prosthesis design under simulated HD and activities of daily living (ADLs) loading. Methods. A novel convertible total elbow prosthesis (LimaCorporate, IT) comprising both ulnar and humeral components that can be linked together by means of an axle, was used. Both typical ADLs and HD torques to be applied to the axle were determined based on finite element analysis (FEA); the boundary load conditions for the FEA were determined based on kinematics analysis on real patients in previous studies. The FEA resultant moment acting on the axle junction during typical ADLs (i.e. feeding with 7.2lbs weight in hand) was 3.2Nm while for HD loads (i.e. sit to stand) was 5.7 Nm. In the experimental setup, 5 axle specimens coupled with 5 ulnar bodies through a tapered connection (5 Nm assembly torque) were fixed to a torque actuator (MTS Bionix) and submerged in a saline solution (9g/l). A moment of 3.2 Nm was applied to the axle for 5M cycles through a fixture to test it under ADLs loading. After 5M cycles, the axles were analyzed with regards to fretting behavior and then re-assembled to test them against HD loading by applying 5.7 Nm for 200K cycles (corresponding to 20 years function). Results. All 5 samples withstood all 5.2M loading cycles without any mechanical failure. At the end of 5M cycles, each axle was still stable as the measured disassembly torque was 3.96 +/−0.18 Nm. Slight signs of fretting were detected on the tapered connection after 5M cycles, however they did not compromise the mechanical connection nor the stability. Discussion and Conclusions. Currently there are no reference standards that properly define protocols for biomechanical testing of elbow prostheses. In the present study, a test to mechanically assess the strength of an axle connection under both typical ADLs and HD loads was set. The connection was able to withstand the imposed conditions. In general, testing of TEA devices should include not only standard ADLs loads but also HD loads, which could be more detrimental for the long-term survivorship. For any figures or tables, please contact authors directly

Introduction. The interaction between the mobile components of total elbow replacements (TER) provides additional constraint to the elbow motion. Semi-constrained TER depend on a mechanical linkage to avoid dislocation and have greater constraint than unconstrained TER that rely primarily in soft tissue for joint stability. Greater constraint increases the load transfer to the implant interfaces and the stresses in the polyethylene components. Both of these phenomena are detrimental to the longevity of TER, as they may result in implant loosening and increased damage to the polyethylene components, respectively[1]. The objective of this work was to compare the constraint profile in varus-valgus and internal-external rotation and the polyethylene stresses under loads from a common daily activity between two semi-constrained TER, Coonrad/Morrey (Zimmer-Biomet) and Discovery® (DJO), and an unconstrained TER, TEMA (LimaCorporate). Methods. We developed finite element (FE) models of the three TER mechanisms. To reduce computational cost, we did not include the humeral and ulnar stems. Materials were linear-elastic for the metallic components (E. Ti6Al4V. =114.3 GPa, E. CoCr. =210 GPa, v=0.33) and linear elastic-plastic for the polyethylene components (E=618 MPa, v=0.46; S. Y. =22 MPa; S. U. =230.6 MPa; ε. U. =1.5 mm/mm). The models were meshed with linear tetrahedral elements of sizes 0.4–0.6 mm. We assumed a friction coefficient of 0.02 between metal and polyethylene. In all simulations, the ulnar component was fixed and the humeral component loaded. We computed the constraint profiles in full extension by simulating each mechanism from 8° varus to 8° valgus and from 8° internal to 8° external rotation. All other degrees-of-freedom except for flexion extension were unconstrained. Then, we identified the instant during feeding that generated the highest moments at the elbow[2], and we applied the joint forces and moments to each TER to evaluate the stresses in the polyethylene. To validate the FE results, we experimentally evaluated the constraint of the design with highest polyethylene stresses in pure internal-external rotation and compared the results against those from a FE model that reproduced the experimental setup (Fig.1-a). Results. For each design, the constraint profiles in varus-valgus (Fig.2-a) were similar to internal-external rotation (Fig.2-b). All designs showed a lax zone in which the mechanisms rotated freely and an engagement zone in which the mobile components contacted, resulting in load transfer. The laxity of the Coonrad/Morrey and the Discovery® was similar and lower than that of the TEMA. After engagement, the stiffness of the TEMA was less than that of the Discovery® and the Coonrad/Morrey. The TEMA showed the lowest polyethylene stresses of all three designs under demanding loads during feeding. Only Discovery® and Coonrad/Morrey had zones reaching permanent deformation (Fig.3). For the Coonrad/Morrey, with the highest polyethylene stresses, the experimental and computational constraint profiles were similar (Fig.1-b). Discussion. The TEMA unconstrained design transferred less moment than semi-constrained designs, reducing the burden on the implant interfaces. Moreover, the TEMA design had lower stresses in the polyethylene components due to the combination of less constraint and a lack of sharp edges on the articular surfaces. For any figures or tables, please contact the authors directly

In Alberta there are over 2,700 hip fractures per year costing the health system over $24 million in acute care costs alone. 50% of hip fracture patients have had a prior fragility fracture as a result of underlying osteoporosis (OP) that has never been assessed or appropriately treated. The Fracture Liaison Service (FLS) in Alberta aims to improve appropriate osteoporosis care, highlight and address gaps within seniors care through OP management, and provide a geriatric syndrome triage service. The FLS has developed a linkage with the Emergency Department (ED) geriatric team whereby hip fracture patients are identified in ED using a screening tool for geriatric syndromes prior to their surgery, allowing the FLS to follow through on comorbidities likely contributing to falls. An inpatient orthopaedic unit with a dedicated Registered Nurse (RN) and a Care of the Elderly Physician see and assess hip fracture patients after surgery for appropriate osteoporosis management and treatment. Screening tools have been developed to quickly detect underlying dementia and to quantify frailty to determine life expectancy and appropriate osteoporosis therapy. Patients are also referred to Geriatric Assessment Units and fall prevention programs. Patients are then contacted in the community at 3, 6,9,12 months by the FLS RN to follow up on osteoporosis therapy, and arrange other needed tests (i.e. bone mineral density, vitamin D) as needed. Information is sent to their family physician with all results. Prior to the patient's discharge from the FLS at one year, a final hand-over letter from the program will be provided outlining the plan of care for the patient. The FLS launched in June 2015 at the Misericordia hospital in Edmonton, Alberta (with plans to expand provincially). Currently 3 out of 4 hip fracture patients per week are being identified in the ED. Ninety-eight hip fracture patients have been identified post-surgery, with 71 patients eligible for enrollment in the program (five deceased patients). Sixty-six (50%) of those enrolled were discharged on osteoporosis medication compared to 8% prior to the program initiation. Seventeen (26%) of those were new medication starts. Of those not started, 7(11%) was patient choice. 11(31%) will be reassessed at 3 months for appropriate therapy. Nineteen (27%) of patients were referred to other inpatient or outpatient programs (i.e. falls, memory). Three month follow up calls have begun with patients for further data collection and a full 1 year qualitative and quantitative evaluation will be done. The implementation of an FLS with dedicated personnel to proactively manage and treat patients with appropriate investigations and interventions can close the care gap that exists in OP care. It also addresses gaps in senior care and provides appropriate referral to community geriatric programs, to improve quality of life and prevent future fractures

There is widespread appreciation amongst orthopaedic surgeons of the importance of thromboprophylaxis. However much of the evidence is based on surrogate outcomes of clinical end-points. This population-based study aims to identify the incidence and trends in venous thromboembolic disease (VTE) following total hip (THR) and knee arthroplasty (TKR) with death or readmission for VTE up to two years following surgery for all patients in Scotland as the primary outcome. We used the Scottish Morbidity Record (SMR01) system to identify all patients undergoing hip or knee arthroplasty over the ten-year period from 1992 to 2001. Patients undergoing cataract surgery over the same period were identified as a control group. Record linkage for all patients to subsequent SMR01 and Registrar General records provided details of further admissions due to DVT or non-fatal PE and deaths within Scotland up to two years after the operation. The cause of death was determined from the Registrar General Records. The incidence of VTE (including fatal pulmonary embolism (PE)) three months following primary THR was 2.27% and primary TKR was 1.79%. The incidence of fatal PE within three months of THR was 0.22% and TKR was 0.15%. The majority of events occurred in the interval from hospital discharge to six weeks after surgery. There was no apparent trend over the period. An apparent reduction in the overall mortality within 365 days of surgery appears to be due to a reduction in the incidence of acute myocardial infarct. The data support the current advice that prophylaxis should be continued for at least six weeks following surgery. Despite increased uptake of prophylaxis regimens and earlier mobilisation, there has been no apparent change in the incidence of symptomatic VTE over the ten-years from 1992 to 2001

International and national predictions from the late 1990s warned of alarming increases in hip fracture incidence due to an ageing population globally. Our study aimed to describe contemporary, population-based longitudinal trends in outcomes and epidemiology of hip fracture patients in a tertiary referral trauma centre. A retrospective review was performed of all patients aged 65 years and over with a diagnosis of fractured neck of femur (AO classification 31 group A and B) admitted to the John Hunter Hospital, Newcastle, New South Wales between 1st January 2002 and 30th December 2009. Datawas collated and cross referenced from several databases (Prospective Long Bone Fracture Database, Operating Theatre Database and the Hospital Coding Unit). Mortality data was obtained via linkage with the Cardiac and Stroke Outcomes Unit, Planning and Performance, Division of Population Health. Main outcome measures were 30-day mortality, in-hospital mortality, length of stay. The JHH admitted (427 ± 20/year, range: 391–455) patients with hip fractures over the 9 year study period. The number of admissions per year increased over the study period (p = 0.002), with no change in the age-standardised incidence (p = 0.1). The average age (83.5 ± 0.2) and average percentage female (73.7%) did not change. There was an overall trend to decreased 30-day mortality from 12.4% in 2002 to 7% in 2009 (p = 0.05). The factors that were associated with increased mortality were age (p < 0.0001), male gender (p = 0.0004), time to operating theatre (p = 0.0428) and length of stay (p < 0.0001). In accordance with national and international projections on increased incidence of geriatric hip fractures, the incidence of fractured neck of femur in our institution increased from 2002–2009, reflecting our ageing population. 30-day mortality improved and longer length of stay corresponded with increased 30-day mortality

Introduction

There is widespread variation in the management of rare orthopaedic disease, in a large part owing to uncertainty. No individual surgeon or hospital is typically equipped to amass sufficient numbers of cases to draw robust conclusions from the information available to them. The programme of research will establish the British Orthopaedic Surgery Surveillance (BOSS) Study; a nationwide reporting structure for rare disease in orthopaedic surgery.