Aims. COVID-19 represents one of the greatest global healthcare challenges in a generation. Orthopaedic departments within the UK have shifted care to manage trauma in ways that minimize exposure to COVID-19. As the incidence of COVID-19 decreases, we explore the impact and risk factors of COVID-19 on patient outcomes within our department. Methods. We retrospectively included all patients who underwent a trauma or urgent orthopaedic procedure from 23 March to 23 April 2020. Electronic records were reviewed for COVID-19 swab results and mortality, and patients were screened by telephone a minimum 14 days postoperatively for symptoms of COVID-19. Results. A total of 214 patients had orthopaedic surgical procedures, with 166 included for analysis. Patients undergoing procedures under general or spinal anaesthesia had a higher risk of contracting perioperative COVID-19 compared to regional/local anaesthesia (p = 0.0058 and p = 0.0007, respectively). In all, 15 patients (9%) had a perioperative diagnosis of COVID-19, 14 of whom had fragility fractures; six died within 30 days of their procedure (40%, 30-day mortality). For proximal femoral fractures, our 30-day mortality was 18.2%, compared to 7% in 2019. Conclusion. Based on our findings, patients undergoing procedures under regional or local anaesthesia have minimal risk of developing COVID-19 perioperatively. Those with multiple comorbidities and fragility fractures have a higher morbidity and mortality if they contract COVID-19 perioperatively; therefore, protective care pathways could go some way to mitigate the risk. Our 30-day mortality of proximal femoral fractures was 18.2% during the COVID-19 pandemic in comparison to the annual national average of 6.1% in 2018 and the University Hospital Coventry average of 7% for the same period in 2019, as reported in the National Hip Fracture Database. Patients undergoing procedures under general or spinal anaesthesia at the peak of the pandemic had a higher risk of contracting perioperative COVID-19 compared to regional block or local anaesthesia. We question whether young patients undergoing day-case procedures under regional block or local anaesthesia with minimal comorbidities require fourteen days self-isolation; instead, we advocate that compliance with personal protective equipment, a negative COVID-19 swab three days prior to surgery, and screening questionnaire may be sufficient. Cite this article: Bone Joint Open 2020;1-9:520–529

Aims. To investigate the effect of polyethylene manufacturing characteristics and irradiation dose on the survival of cemented and reverse hybrid total hip arthroplasties (THAs). Methods. In this registry study, data from the National Joint Registry of England, Wales, Northern Ireland and the Isle of Man (NJR) were linked with manufacturing data supplied by manufacturers. The primary endpoint was revision of any component. Cox proportional hazard regression was a primary analytic approach adjusting for competing risk of death, patient characteristics, head composition, and stem fixation. Results. A total of 290,770 primary THAs were successfully linked with manufacturing characteristics. Overall 4,708 revisions were analyzed, 1,260 of which were due to aseptic loosening. Total radiation dose was identified as a risk factor and included in the Cox model. For statistical modelling of aseptic loosening, THAs were grouped into three categories: G1 (no radiation); G2 ( > 0 to < 5 Mrad); and G3 ( ≥ 5 Mrad). G1 had the worst survivorship. The Cox regression hazard ratio for revision due to aseptic loosening for G2 was 0.7 (95% confidence interval (CI) 0.58 to 0.83), and for G3 0.4 (95% CI 0.30 to 0.53). Male sex and uncemented stem fixation were associated with higher risk of revision and ceramic heads with lower risk. Conclusion. Polyethylene irradiation was associated with reduced risk of revision for aseptic loosening. Radiation doses of ≥ 5 Mrad were associated with a further reduction in risk. Cite this article: Bone Joint Res 2020;9(9):563–571

Introduction. Studies have addressed the issue of increasing prevalence of work-related musculoskeletal (MSK) pain among different occupations. However, contributing factors to MSK pain have not been fully investigated among orthopaedic surgeons. Thus, this study aimed to approximate the prevalence and predictors of MSK pain among Saudi orthopaedic surgeons working in Riyadh, Saudi Arabia. Methods. A cross-sectional study using an electronic survey was conducted in Riyadh. The questionnaire was distributed through email among orthopaedic surgeons in Riyadh hospitals. Standardized Nordic questionnaires for the analysis of musculoskeletal symptoms were used. Descriptive measures for categorical and numerical variables were presented. Student’s t-test and Pearson’s χ2 test were used. The level of statistical significance was set at p ≤ 0.05. Results. The response rate was 80.3%, with a total number of 179 of Saudi orthopaedic surgeons (173 males and six females). Of our sample, 67.0% of the respondents complained of having MSK pain. The most commonly reported MSK pain was lower back (74.0%), followed by neck (58.2%). Age and body mass index were implicated in the development of more than one type of MSK pain. Increased years of experience (≥ 6 years) was linked to shoulder/elbow, lower back, and hip/thigh pain. Smoking is widely associated with lower back pain development, whereas physicians who do not smoke and exercise regularly reported fewer pain incidences. Excessive bending and twisting during daily practice have been correlated with increased neck pain. Conclusion. MSK pain was found to be common among Saudi orthopaedic surgeons. Further extensive research should be conducted to understand and analyze the risk factors involved and search for possible improvements to avoid further complications. However, ergonomics education during surgical training could be effective at modifying behaviors and reducing MSK pain manifestations

Aims. Primary (or spontaneous) and secondary osteonecrosis of the knee can lead to severe joint degeneration, for which either total or unicompartmental arthroplasty may be considered. However, there are limited studies analyzing outcomes of unicompartmental knee arthroplasties (UKAs) for osteonecrosis involving an isolated compartment of the knee. The aims of this study were to analyze outcomes of UKAs for osteonecrosis with specific focus on 1) survivorship free of any revision or reoperation, 2) risk factors for failure, 3) clinical outcomes, and 4) complications. Patients and Methods. A total of 45 patients underwent 46 UKAs for knee osteonecrosis between 2002 and 2014 at our institution (The Mayo Clinic, Rochester, Minnesota). Twenty patients (44%) were female; the mean age of the patients was 66 years, and mean body mass index (BMI) was 31 kg/m. 2. Of the 46 UKAs, 44 (96%) were medial UKAs, and 35 (76%) were fixed-bearing design. Mean mechanical axis postoperatively was 1.5° varus (0° to 5° varus); 41 UKAs (89%) were performed for primary osteonecrosis. Mean follow-up was five years (2 to 12). Results. Survivorship free of any revision in the cohort was 89% (95% CI 77 to 99) and 76% (95% CI 53 to 99) at five and ten years, respectively. In patients undergoing UKA for primary osteonecrosis survivorship free of any revision was 93% (95% CI 83 to 100)at both five and ten years. Secondary osteonecrosis was a significant risk factor for poorer survivorship free of any revision or reoperation (hazard ratio 7.7, p = 0.03). Three medial UKAs (6.5%) were converted to total knee arthroplasties (TKAs): two for lateral compartment degeneration and one for development of lateral osteonecrosis. No implants were revised for loosening, fracture, or wear. Knee Society scores improved from a mean of 60 (44 to 72) preoperatively to a mean of 94 postoperatively (82 to 100) (p < 0.001). There were no surgical complications. Conclusion. When done for primary osteonecrosis of the knee, UKA resulted in reliable clinical improvement, minimal complications, and durable estimated implant survivorship free of revision at ten years. UKA done for secondary osteonecrosis was substantially less durable at mid-term follow-up. Progression of knee degeneration, rather than implant failure or loosening, was most common indication for conversion to TKA. Cite this article: Bone Joint J 2018;100-B:450–4

Aims. Cigarette smoking has a negative impact on the skeletal system, causes a decrease in bone mass in both young and old patients, and is considered a risk factor for the development of osteoporosis. In addition, it disturbs the bone healing process and prolongs the healing time after fractures. The mechanisms by which cigarette smoking impairs fracture healing are not fully understood. There are few studies reporting the effects of cigarette smoking on new blood vessel formation during the early stage of fracture healing. We tested the hypothesis that cigarette smoke inhalation may suppress angiogenesis and delay fracture healing. Methods. We established a custom-made chamber with airflow for rats to inhale cigarette smoke continuously, and tested our hypothesis using a femoral osteotomy model, radiograph and microCT imaging, and various biomechanical and biological tests. Results. In the smoking group, Western blot analysis and immunohistochemical staining revealed less expression of vascular endothelial growth factor (VEGF) and von Willebrand factor (vWF). The smoking group also had a lower microvessel density than the control group. Image and biochemical analysis also demonstrated delayed bone healing. Conclusion. Cigarette smoke inhalation was associated with decreased expression of angiogenic markers in the early bone healing phase and with impaired bone healing. Cite this article:Bone Joint Res. 2020;9(3):99–107

Aims. Previous studies have reported an increased risk for postoperative complications in the Medicaid population undergoing total hip arthroplasty (THA). These studies have not controlled for the surgeon’s practice or patient care setting. This study aims to evaluate whether patient point of entry and Medicaid status plays a role in quality outcomes and discharge disposition following THA. Methods. The electronic medical record at our institution was retrospectively reviewed for all primary, unilateral THA between January 2016 and January 2018. THA recipients were categorized as either Medicaid or non-Medicaid patients based on a visit to our institution’s Hospital Ambulatory Care Center (HACC) within the six months prior to surgery. Only patients who had been operated on by surgeons (CML, JV, JDS, RS) with at least ten Medicaid and ten non-Medicaid patients were included in the study. The patients included in this study were 56.33% female, had a mean age of 60.85 years, and had a mean BMI of 29.14. The average length of follow-up was 343.73 days. Results. A total of 426 hips in 403 patients were included in this study, with 114 Medicaid patients and 312 non-Medicaid patients. Medicaid patients had a significantly lower mean age (54.68 years (SD 12.33) vs 63.10 years (SD 12.38); p < 0.001), more likely to be black or ‘other’ race (27.19% vs 13.46% black; 26.32% vs 12.82% other; p < 0.001), and more likely to be a current smoker (19.30% vs 9.29%; p = 0.001). After adjusting for patient risk factors, there was a significant Medicaid effect on length of stay (LOS) (rate ratio 1.129, 95% confidence interval (CI) 1.048 to 1.216; p = 0.001) and facility discharge (odds ratio 2.010, 95% CI 1.398 to 2.890; p < 0.001). There was no Medicaid effect on surgical time (exponentiated β coefficient 1.015, 95% CI 0.995 to 1.036; p = 0.136). There was no difference in 30-day readmission, 90-day readmission, 30-day infections, 90-day infections, and 90-day mortality between the two groups. Conclusion. After controlling for patient variables, there was a statistically significant Medicaid effect on LOS and facility discharge. These results indicate that clinically similar outcomes can be achieved for Medicaid patients; however, further work is needed on maximizing social support and preoperative patient education with a focus on successful home discharge. Cite this article: Bone Joint J 2020;102-B(7 Supple B):78–84

Aims. Recent studies have suggested that corticosteroid injections into the knee may harm the joint resulting in cartilage loss and possibly accelerating the progression of osteoarthritis (OA). The aim of this study was to assess whether patients with, or at risk of developing, symptomatic osteoarthritis of the knee who receive intra-articular corticosteroid injections have an increased risk of requiring arthroplasty. Methods. We used data from the Osteoarthritis Initiative (OAI), a multicentre observational cohort study that followed 4,796 patients with, or at risk of developing, osteoarthritis of the knee on an annual basis with follow-up available up to nine years. Increased risk for symptomatic OA was defined as frequent knee symptoms (pain, aching, or stiffness) without radiological evidence of OA and two or more risk factors, while OA was defined by the presence of both femoral osteophytes and frequent symptoms in one or both knees. Missing data were imputed with multiple imputations using chained equations. Time-dependent propensity score matching was performed to match patients at the time of receving their first injection with controls. The effect of corticosteroid injections on the rate of subsequent (total and partial) knee arthroplasty was estimated using Cox proportional-hazards survival analyses. Results. After removing patients lost to follow-up, 3,822 patients remained in the study. A total of 249 (31.3%) of the 796 patients who received corticosteroid injections, and 152 (5.0%) of the 3,026 who did not, had knee arthroplasty. In the matched cohort, Cox proportional-hazards regression resulted in a hazard ratio of 1.57 (95% confidence interval (CI) 1.37 to 1.81; p < 0.001) and each injection increased the absolute risk of arthroplasty by 9.4% at nine years’ follow-up compared with those who did not receive injections. Conclusion. Corticosteroid injections seem to be associated with an increased risk of knee arthroplasty in patients with, or at risk of developing, symptomatic OA of the knee. These findings suggest that a conservative approach regarding the treatment of these patients with corticosteroid injections should be recommended. Cite this article: Bone Joint J 2020;102-B(5):586–592

Aims. The aim of this study was to characterize the relationship between pre- and postoperative opioid use among patients undergoing common elective orthopaedic procedures. Patients and Methods. Pre- and postoperative opioid use were studied among patients from a national insurance database undergoing seven common orthopaedic procedures using univariate log-rank tests and multivariate Cox proportional hazards analyses. Results. A total of 98 769 patients were included; 35 701 patients were opioid-naïve, 11 621 used opioids continuously for six months before surgery, and 4558 used opioids continuously for at least six months but did not obtain any prescriptions in the three months before surgery. Among opioid-naïve patients, between 0.76% and 4.53% used opioids chronically postoperatively. Among chronic preoperative users, between 42% and 62% ceased chronic opioids postoperatively. A three-month opioid-free period preoperatively led to a rate of cessation of chronic opioid use between 82% and 93%, as compared with between 31% and 50% with continuous preoperative use (p < 0.001 for significant changes in opioid use before and after surgery in each procedure). Between 5.6 and 20.0 preoperative chronic users ceased chronic use for every new chronic opioid user. Risk factors for chronic postoperative use included chronic preoperative opioid use (odds ratio (OR) 4.84 to 39.75; p < 0.0001) and depression (OR 1.14 to 1.55; p < 0.05 except total hip arthroplasty). With a three-month opioid-free period before surgery, chronic preoperative opioids elevated the risk of chronic opioid use only mildly, if at all (OR 0.47 to 1.75; p < 0.05 for total shoulder arthroplasty, rotator cuff repair, and carpal tunnel release). Conclusion. Chronic preoperative opioid use increases the risk of chronic postoperative use, but an opioid-free period before surgery decreases this risk compared with continuous preoperative use. Cite this article: Bone Joint J 2019;101-B:1570–1577

Aims. Magnetically controlled growing rods (MCGR) have been gaining popularity in the management of early-onset scoliosis (EOS) over the past decade. We present our experience with the first 44 MCGR consecutive cases treated at our institution. Methods. This is a retrospective review of consecutive cases of MCGR performed in our institution between 2012 and 2018. This cohort consisted of 44 children (25 females and 19 males), with a mean age of 7.9 years (3.7 to 13.6). There were 41 primary cases and three revisions from other rod systems. The majority (38 children) had dual rods. The group represents a mixed aetiology including idiopathic (20), neuromuscular (13), syndromic (9), and congenital (2). The mean follow-up was 4.1 years, with a minimum of two years. Nine children graduated to definitive fusion. We evaluated radiological parameters of deformity correction (Cobb angle), and spinal growth (T1-T12 and T1-S1 heights), as well as complications during the course of treatment. Results. The mean Cobb angles pre-operatively, postoperatively, and at last follow-up were 70° (53 to 103), 35° (15 to 71) and 39° (15 to 65) respectively (p < 0.001). Further, there was a mean of 14° (-6 to 27) of additional Cobb angle correction upon graduation from MCGR to definitive fusion. Both T1-T12 and T1-S1 showed significant increase in heights of 27 mm and 45 mm respectively at last follow-up (p < 0.001). Ten children (23%) developed 18 complications requiring 21 unplanned operations. Independent risk factors for developing a complication were single rod constructs and previous revision surgery. Conclusion. MCGR has the benefit of avoiding multiple surgeries, and is an effective tool in treatment of early-onset scoliosis. It also maintains the flexibility of the spine, allowing further correction at the time of definitive fusion. Cite this article: Bone Joint Open 2020;1-7:405–414

Aims. Trochlear dysplasia is a significant risk factor for patellofemoral instability. The Dejour classification is currently considered the standard for classifying trochlear dysplasia, but numerous studies have reported poor reliability on both plain radiography and MRI. The severity of trochlear dysplasia is important to establish in order to guide surgical management. We have developed an MRI-specific classification system to assess the severity of trochlear dysplasia, the Oswestry-Bristol Classification (OBC). This is a four-part classification system comprising normal, mild, moderate, and severe to represent a normal, shallow, flat, and convex trochlear, respectively. The purpose of this study was to assess the inter- and intraobserver reliability of the OBC and compare it with that of the Dejour classification. Methods. Four observers (two senior and two junior orthopaedic surgeons) independently assessed 32 CT and axial MRI scans for trochlear dysplasia and classified each according to the OBC and the Dejour classification systems. Assessments were repeated following a four-week interval. The inter- and intraobserver agreement was determined by using Fleiss’ generalization of Cohen’s kappa statistic and S-statistic nominal and linear weights. Results. The OBC showed fair-to-good interobserver agreement and good-to-excellent intraobserver agreement (mean kappa 0.68). The Dejour classification showed poor interobserver agreement and fair-to-good intraobserver agreement (mean kappa 0.52). Conclusion. The OBC can be used to assess the severity of trochlear dysplasia. It can be applied in clinical practice to simplify and standardize surgical decision-making in patients with recurrent patella instability. Cite this article: Bone Joint J 2020;102-B(1):102–107

Aims. Few studies dealing with chondrosarcoma of the pelvis are currently available. Different data about the overall survival and prognostic factors have been published but without a detailed analysis of surgery-related complications. We aimed to analyse the outcome of a series of pelvic chondrosarcomas treated at a single institution, with particular attention to the prognostic factors. Based on a competing risk model, our objective was to identify risk factors for the development of complications. Patients and Methods. In a retrospective single-centre study, 58 chondrosarcomas (26 patients alive, 32 patients dead) of the pelvis were reviewed. The mean follow-up was 13 years (one week to 23.1 years). Results. A total of 26 patients (45%) were alive and 32 patients (55%) had died. Overall survival was 76%, 55% and 45% at one, five and ten years post-operatively, respectively. In a competing risk model the cumulative risk of the development of a surgery-related complication was 64% at six months and 69% at one year, post-operatively, respectively. Endoprosthetic reconstruction was a significant risk factor for the development of complications (p = 0.006). Complications were not significantly related to age or the location or grade of the tumour (p = 0.823, p = 0.976, p = 0.858). The development of complications did not have a negative effect on survival (p = 0.147). Conclusion. This is the first study with competing risk analysis of surgery-related complications in patients with a pelvic chondrosarcoma. The surgery in these patients remains prone to complications. Endoprosthetic reconstruction significantly increases the risk of the development of complications (p = 0.006). A competing risk model showed that the development of complications does not have a negative influence on overall survival (p = 0.147). An aggressive, surgical resection with the goal of achieving wide margins whenever possible remains the mainstay of treatment. . Cite this article: Bone Joint J 2017;99-B:686–96

Aims. Osseointegrated prosthetic limbs allow better mobility than socket-mounted prosthetics for lower limb amputees. Fractures, however, can occur in the residual limb, but they have rarely been reported. Approximately 2% to 3% of amputees with socket-mounted prostheses may fracture within five years. This is the first study which directly addresses the risks and management of periprosthetic osseointegration fractures in amputees. Methods. A retrospective review identified 518 osseointegration procedures which were undertaken in 458 patients between 2010 and 2018 for whom complete medical records were available. Potential risk factors including time since amputation, age at osseointegration, bone density, weight, uni/bilateral implantation and sex were evaluated with multiple logistic regression. The mechanism of injury, technique and implant that was used for fixation of the fracture, pre-osseointegration and post fracture mobility (assessed using the K-level) and the time that the prosthesis was worn for in hours/day were also assessed. Results. There were 22 periprosthetic fractures; they occurred exclusively in the femur: two in the femoral neck, 14 intertrochanteric and six subtrochanteric, representing 4.2% of 518 osseointegration operations and 6.3% of 347 femoral implants. The vast majority (19/22, 86.4%) occurred within 2 cm of the proximal tip of the implant and after a fall. No fractures occurred spontaneously. Fixation most commonly involved dynamic hip screws (10) and reconstruction plates (9). No osseointegration implants required removal, the K-level was not reduced after fixation of the fracture in any patient, and all retained a K-level of ≥ 2. All fractures united, 21 out of 22 patients (95.5%) wear their osseointegration-mounted prosthetic limb longer daily than when using a socket, with 18 out of 22 (81.8%) reporting using it for ≥ 16 hours daily. Regression analysis identified a 3.89-fold increased risk of fracture for females (p = 0.007) and a 1.02-fold increased risk of fracture per kg above a mean of 80.4 kg (p = 0.046). No increased risk was identified for bilateral implants (p = 0.083), time from amputation to osseointegration (p = 0.974), age at osseointegration (p = 0.331), or bone density (g/cm2, p = 0.560; T-score, p = 0.247; Z-score, p = 0.312). Conclusion. The risks and sequelae of periprosthetic fracture after press-fit osseointegration for amputation should not deter patients or clinicians from considering this procedure. Females and heavier patients are likely to have an increased risk of fracture. Age, years since amputation, and bone density do not appear influential. Cite this article: Bone Joint J 2020;102-B(2):162–169

Aims. This study aimed to explore whether intraoperative nerve monitoring can identify risk factors and reduce the incidence of nerve injury in patients with high-riding developmental dysplasia. Patients and Methods. We conducted a historical controlled study of patients with unilateral Crowe IV developmental dysplasia of the hip (DDH). Between October 2016 and October 2017, intraoperative nerve monitoring of the femoral and sciatic nerves was applied in total hip arthroplasty (THA). A neuromonitoring technician was employed to monitor nerve function and inform the surgeon of ongoing changes in a timely manner. Patients who did not have intraoperative nerve monitoring between September 2015 and October 2016 were selected as the control group. All the surgeries were performed by one surgeon. Demographics and clinical data were analyzed. A total of 35 patients in the monitoring group (ten male, 25 female; mean age 37.1 years (20 to 46)) and 56 patients in the control group (13 male, 43 female; mean age 37.9 years (23 to 52)) were enrolled. The mean follow-up of all patients was 13.1 months (10 to 15). Results. The two groups had no significant differences in preoperative data. In the monitoring group, ten nerve alerts occurred intraoperatively, and no neural complications were detected postoperatively. In the control group, six patients had neural complications. The rate of nerve injury was lower in the monitoring group than in the control group, but this did not achieve statistical significance. The degree of leg lengthening was significantly greater in the monitoring group than in the control group. In further analyses, patients who had previous hip surgery were more likely to have intraoperative nerve alerts and postoperative nerve injury. Conclusion. Nerve injury usually occurred during the processes of exposure and reduction. The use of intraoperative nerve monitoring showed a trend towards reduced nerve injury in THA for Crowe IV DDH patients. Hence, we recommend its routine use in patients undergoing leg lengthening, especially in those with previous hip surgery. Cite this article: Bone Joint J 2019;101-B:1438–1446

Aims. Varus-valgus constrained (VVC) implants are often used during revision total knee arthroplasty (TKA) to gain coronal plane stability. However, the increased mechanical torque applied to the bone-cement interface theoretically increases the risk of aseptic loosening. We assessed mid-term survivorship, complications, and clinical outcomes of a fixed-bearing VVC device in revision TKAs. Methods. A total of 416 consecutive revision TKAs (398 patients) were performed at our institution using a single fixed-bearing VVC TKA from 2007 to 2015. Mean age was 64 years (33 to 88) with 50% male (199). Index revision TKA diagnoses were: instability (n = 122, 29%), aseptic loosening (n = 105, 25%), and prosthetic joint infection (PJI) (n = 97, 23%). All devices were cemented on the epiphyseal surfaces. Femoral stems were used in 97% (n = 402) of cases, tibial stems in 95% (n = 394) of cases; all were cemented. In total, 93% (n = 389) of cases required a stemmed femoral and tibial component. Femoral cones were used in 29%, and tibial cones in 40%. Survivorship was assessed via competing risk analysis; clinical outcomes were determined using Knee Society Scores (KSSs) and range of movement (ROM). Mean follow-up was four years (2 to 10). Results. The five-year cumulative incidence of subsequent revision for aseptic loosening and instability were 2% (95% confidence interval (CI) 0.2 to 3, number at risk = 154) and 4% (95% CI 2 to 6, number at risk = 153), respectively. The five-year cumulative incidence of any subsequent revision was 14% (95% CI 10 to 18, number at risk = 150). Reasons for subsequent revision included PJI (n = 23, of whom 12 had previous PJI), instability (n = 13), and aseptic loosening (n = 11). The use of this implant without stems was found to be a significant risk factor for subsequent revision (hazard ratio (HR) 7.58 (95% CI 3.98 to 16.03); p = 0.007). KSS improved from 46 preoperatively to 81 at latest follow-up (p < 0.001). ROM improved from 96° prerevision to 108° at latest follow-up (p = 0.016). Conclusion. The cumulative incidence of subsequent revision for aseptic loosening and instability was very low at five years with this fixed-bearing VVC implant in revision TKAs. Routine use of cemented and stemmed components with targeted use of metaphyseal cones likely contributed to this low rate of aseptic loosening. Cite this article: Bone Joint J 2020;102-B(4):458–462

McFarland fractures of the medial malleolus in children, also classified as Salter–Harris Type III and IV fractures, are associated with a high incidence of premature growth plate arrest. In order to identify prognostic factors for the development of complications we reviewed 20 children with a McFarland fracture that was treated surgically, at a mean follow-up of 8.9 years (3.5 to 17.4). Seven children (35%) developed premature growth arrest with angular deformity. The mean American Orthopaedic Foot and Ankle Society Ankle-Hindfoot Scale for all patients was 98.3 (87 to 100) and the mean modified Weber protocol was 1.15 (0 to 5). There was a significant correlation between initial displacement (p = 0.004) and operative delay (p = 0.007) with premature growth arrest. Both risk factors act independently and additively, such that all children with both risk factors developed premature arrest whereas children with no risk factor did not. We recommend that fractures of the medial malleolus in children should be treated by anatomical reduction and screw fixation within one day of injury. Cite this article: Bone Joint J 2013;95-B:419–23

Aims. The aim of this study was to estimate the 90-day risk of revision for periprosthetic femoral fracture associated with design features of cementless femoral stems, and to investigate the effect of a collar on this risk using a biomechanical in vitro model. Materials and Methods. A total of 337 647 primary total hip arthroplasties (THAs) from the United Kingdom National Joint Registry (NJR) were included in a multivariable survival and regression analysis to identify the adjusted hazard of revision for periprosthetic fracture following primary THA using a cementless stem. The effect of a collar in cementless THA on this risk was evaluated in an in vitro model using paired fresh frozen cadaveric femora. Results. The prevalence of early revision for periprosthetic fracture was 0.34% (1180/337 647) and 44.0% (520/1180) occurred within 90 days of surgery. Implant risk factors included: collarless stem, non-grit-blasted finish, and triple-tapered design. In the in vitro model, a medial calcar collar consistently improved the stability and resistance to fracture. Conclusion. Analysis of features of stem design in registry data is a useful method of identifying implant characteristics that affect the risk of early periprosthetic fracture around a cementless femoral stem. A collar on the calcar reduced the risk of an early periprosthetic fracture and this was confirmed by biomechanical testing. This approach may be useful in the analysis of other uncommon modes of failure after THA. Cite this article: Bone Joint J 2019;101-B:779–786

Aims. It is uncertain whether instrumented spinal fixation in nonambulatory children with neuromuscular scoliosis should finish at L5 or be extended to the pelvis. Pelvic fixation has been shown to be associated with up to 30% complication rates, but is regarded by some as the standard for correction of deformity in these conditions. The incidence of failure when comparing the most caudal level of instrumentation, either L5 or the pelvis, using all-pedicle screw instrumentation has not previously been reported. In this retrospective study, we compared nonambulatory patients undergoing surgery at two centres: one that routinely instrumented to L5 and the other to the pelvis. Methods. In all, 91 nonambulatory patients with neuromuscular scoliosis were included. All underwent surgery using bilateral, segmental, pedicle screw instrumentation. A total of 40 patients underwent fusion to L5 and 51 had their fixation extended to the pelvis. The two groups were assessed for differences in terms of clinical and radiological findings, as well as complications. Results. The main curve (MC) was a mean of 90° (40° to 141°) preoperatively and 46° (15° to 82°) at two-year follow-up in the L5 group, and 82° (33° to 116°) and 19° (1° to 60°) in the pelvic group (p < 0.001 at follow-up). Correction of MC and pelvic obliquity (POB) were statistically greater in the pelvic group (p < 0.001). There was no statistically significant difference in the operating time, blood loss, or complications. Loss of MC correction (> 10°) was more common in patients fixated to the pelvis (23% vs 3%; p = 0.032), while loss of pelvic obliquity correction was more frequent in the L5 group (25% vs 0%; p = 0.007). Risk factors for loss of correction (either POB or MC) included preoperative coronal imbalance (> 50 mm, odds ratio (OR) 11.5, 95%confidence interval (CI) 2.0 to 65; p = 0.006) and postoperative sagittal imbalance (> 25 mm, OR 11.0, 95% CI1.9 to 65; p = 0.008). Conclusion. We found that patients undergoing pelvic fixation had a greater correction of MC and POB. The rate of complications was not different. Preoperative coronal and postoperative sagittal imbalance were associated with increased risks of loss of correction, regardless of extent of fixation. Therefore, we recommend pelvic fixation in all nonambulatory children with neuromuscular scoliosis where coronal or sagittal imbalance are present preoperatively. Cite this article: Bone Joint J 2020;102-B(2):261–267

Aims. The primary aim of this study was to determine if delayed clavicular fixation results in a greater risk of operative complications and revision surgery. Patients and Methods. A retrospective case series was undertaken of all displaced clavicular fractures that underwent plate fixation over a ten-year period (2007 to 2017). Patient demographics, time to surgery, complications, and mode of failure were collected. Logistic regression was used to identify independent risk factors contributing towards operative complications. Receiver operating characteristic (ROC) curve analysis was used to determine if a potential ‘safe window’ exists from injury to delayed surgery. Propensity score matching was used to construct a case control study for comparison of risk. Results. A total of 259 patients were included in the analysis. Postoperative infection occurred in 3.9% of all patients (n = 10); the only variable associated was a greater time interval from injury to fixation (p = 0.001). Failed primary surgery requiring revision fixation was required in 7.7% of the cohort (n = 20), with smoking (p < 0.001), presence of a postoperative infection (p < 0.001), increasing age (p = 0.018), and greater time delay from injury to surgery (p = 0.015) identified as significant independent predictors on regression analysis. ROC analysis revealed that surgery beyond 96 days from injury increased the rate of major complications and revision surgery. Using a matched case cohort of cases before (n = 67) and after (n = 77) the ‘safe window’, the risk of postoperative infection increased (odds ratio (OR) 7.7, 95% confidence interval (CI) 1.9 to 62.9; p = 0.028), fixation failure (OR 3.8, 95% CI 1.2 to 12.1; p = 0.017) and revision surgery (OR 4.8, 95% CI 1.5 to 15.0; p = 0.004). Conclusion. A delay to primary fixation of up to three months following injury may be acceptable, beyond which there is an increased risk of major operative complications and revision surgery. Cite this article: Bone Joint J 2019;101-B:1385–1391

Aims. Low haemoglobin (Hb) at admission has been identified as a risk factor for mortality for elderly patients with hip fractures in some studies. However, this remains controversial. This study aims to analyze the association between Hb level at admission and mortality in elderly patients with hip fracture undergoing surgery. Patients and Methods. All consecutive patients (prospective database) admitted with hip fracture operated in a tertiary hospital between 2012 and 2016 were analyzed. We collected patient characteristics, time to surgery, duration and type of surgery, comorbidities, Hb at admission, nadir of Hb after surgery, the use and amount of red blood cells (RBCs) transfusion products, postoperative complications, and death. The main outcome measures were mortality at 30 days, 90 days, 180 days, and one year after surgery. Results. We included 829 patients; the mean age was 81 years (. sd. 11). Mortality at 30 days, 90 days, 180 days, and one year was 5.7%, 12.3%, 18.1%, and 23.5%, respectively. The highest mortality was observed in patients aged over 80 years (162/557, 29%) and in male patients (85/267, 32%). Survival at 90 days, 180 days, and one year after surgery was significantly lower in patients with a Hb level below 120 g/l at admission. In multivariate analysis, Hb level below 120 g/l at admission was found to be an independent factor associated with mortality (adjusted hazard ratio (aHR) 1.68 (95% confidence interval (CI) 1.22 to 2.31); p = 0.001), along with age (aHR 1.06 (95% CI 1.04 to 1.06); p < 0.001), male sex (aHR 2.19 (95% CI 1.61 to 2.96); p < 0.001), and need for RBC transfusions (aHR 1.10 (95% CI 1.02 to 1.19); p = 0.01). Conclusion. Our results suggest that low Hb at admission along with age and RBC transfusions is significantly associated with short- and long-term mortality after hip fracture surgery, independently of comorbidity confounders. Further studies should be performed to understand how preoperative Hb could be taken into account in perioperative management. Cite this article: Bone Joint J 2019;101-B:1122–1128

There is a disparity in sport-related injuries between sexes, with females sustaining non-contact musculoskeletal injuries at a higher rate. Anterior cruciate ligament ruptures are between two and eight times more common than in males, and females also have a higher incidence of ankle sprains, patellofemoral pain, and bone stress injuries. The sequelae of such injuries can be devastating to an athlete, resulting in time out of sport, surgery, and the early onset of osteoarthritis. It is important to identify the causes of this disparity and introduce prevention programmes to reduce the incidence of these injuries. A natural difference reflects the effect of reproductive hormones in females, which have receptors in certain musculoskeletal tissues. Relaxin increases ligamentous laxity. Oestrogen decreases the synthesis of collagen and progesterone does the opposite. Insufficient diet and intensive training can lead to menstrual irregularities, which are common in female athletes and result in injury, whereas oral contraception may have a protective effect against certain injuries. It is important for coaches, physiotherapists, nutritionists, doctors, and athletes to be aware of these issues and to implement preventive measures. This annotation explores the relationship between the menstrual cycle and orthopaedic sports injuries in pre-menopausal females, and proposes recommendations to mitigate the risk of sustaining these injuries.

Cite this article: Bone Joint J 2023;105-B(7):723–728.