Abstract. Objectives. The aim of this study was to investigate whether mechanical loading induced by physical activity can reduce risk of sarcopenia in middle-aged adults. Methods. This was a longitudinal study based on a subset of UK Biobank data consisting of 1,918 participants (902 men and 1,016 women, mean age 56 years) who had no sarcopenia at baseline (assessed between 2006 and 2010). The participants were assessed again after 6 years at follow-up, and were categorized into no sarcopenia, probable sarcopenia, or sarcopenia according to the definition and algorithm developed in 2018 by European Working Group on Sarcopenia in Older People (EWGSOP). Physical activity was assessed at a time between baseline and follow-up using 7-day acceleration data obtained from wrist worn accelerometers. Raw acceleration data were then analysed to study the mechanical loading of physical activity at different intensities (i.e. very light, light, moderate-to-vigorous). Multinominal logistic regression was employed to examine the association between the incidence of sarcopenia and physical activity loading, between baseline and follow up, controlled for other factors at baseline including age, gender, BMI, smoking status, intake of alcohol, vitamin D and calcium, history of rheumatoid arthritis, osteoarthritis, secondary osteoporosis, and type 2 diabetes. Results. Among the 1918 participants with no sarcopenia at baseline, 230 (69 men and 161 women) developed probable sarcopenia and 37 (14 men and 23 women) developed sarcopenia at follow-up. Physical activity loading at moderate-to-vigorous intensity was higher in men (p<0.05), while women had higher physical activity loading at very light intensity (p<0.05). No significant difference was found in physical activity loading at light intensity between men and women (p>0.05). Logistic regression models showed that increase in physical activity loading at moderate-to-vigorous intensity significantly reduced the risk of sarcopenia (odds ratio = 0.368, p<0.05), but not probable sarcopenia (odds ratio = 0.974, p>0.05), while loading at light or very light activity intensity were not associated with the risk of sarcopenia or probable sarcopenia (p>0.05). Conclusion. Loading of physical activity at moderate-to-vigorous intensity could reduce risk of sarcopenia in middle-aged adults. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

In a clinical setting, there is a need for simple gait kinematic measurements to facilitate objective unobtrusive patient monitoring. The objective of this study is to determine if a learned classification model's output can be used to monitor a person's recovery status post-TKA. The gait kinematics of 20 asymptomatic and 17 people with TKA were measured using a full-body Xsens model. 1. The experimental group was measured at 6 weeks, 3, 6, and 12 months post-surgery. Joint angles of the ankle, knee, hip, and spine per stride (10 strides) were extracted from the Xsens software (MVN Awinda studio 4.4). 1. . Statistical features for each subject at each evaluation moment were derived from the kinematic time-series data. We normalised the features using standard scaling. 2. We trained a logistic regression (LR) model using L1-regularisation on the 6 weeks post-surgery data2–4. After training, we applied the trained LR- model to the normalised features computed for the subsequent timepoints. The model returns a score between 0 (100% confident the person is an asymptomatic control) and 1 (100% confident this person is a patient). The decision boundary is set at 0.5. The classification accuracy of our LR-model was 94.58%. Our population's probability of belonging to the patient class decreases over time. At 12 months post-TKA, 38% of our patients were classified as asymptomatic

The Royal College of Surgeons of England (RCS) Good Surgical Practice guidance identifies essential criteria for surgical operation note documentation. The current quality improvement project aims to identify if using pre-templated operation notes for documenting fractured neck of femur surgery results in improved documentation when compared to free hand orthopaedic operation notes. A total of fourteen categories were identified from the RCS guidance as required across all the operations identified in this study. All operations for the month of October 2021 were identified and the operation notes analysed. Pre-templated operation notes were compared to free hand operation notes. 97 cases were identified, of which 74 were free hand operation notes and 23 were pre-templated fractured neck of femur operation notes. All fourteen categories were completed in 13 (57%) of the templated operation notes vs 0 (0%) in the free hand operation notes (odds ratio 0.0052, 95% CI 0.0003 to 0.0945, p < 0.001). The median total number of completed categories was significantly higher in the templated op-note group compared to the free hand op-note group (templated median 14, range 12-14, vs. free hand median 11, range 9 to 13, p < 0.001). Logistic regression analysis of operation notes written by Registrars or Consultants identified Registrars as more likely to document the antibiotic prophylaxis given (p = 0.025). Use of pre-templated operation notes results in significantly improved documentation. Adoption of generic pre-templated operation notes to improve surgical documentation should be considered across all operations

We investigated factors associated with postoperative lipiduria and hypoxemia in patients undergoing surgery for orthopedic fractures. We enrolled patients who presented to our emergency department due to traumatic fractures between 2016 and 2017. We collected urine samples within 24 hours after the patients had undergone surgery to determine the presence of lipiduria. Hypoxemia was defined as an SpO2 <95% determined with a pulse oximeter during the hospitalization. Patients’ anthropometric data, medical history, and laboratory test results were collected from the electronic medical record. Logistic regression analyses were used to determine the associations of clinical factors with postoperative lipiduria and hypoxemia with multivariate adjustment. A total of 144 patients were analyzed (mean age 51.3 ± 22.9 years, male 50.7%). Diabetes (odd ratio 3.684, 95% CI 1.256-10.810, p=0.018) and operation time (odd ratio 1.005, 95% CI 1.000-1.009, p=0.029) were independently associated with postoperative lipiduria, while age (odd ratio 1.034, 95% CI 1.003-1.066, p=0.029), body mass index (odd ratio 1.100, 95% CI 1.007-1.203, p=0.035), and operation time (odd ratio 1.005, 95% CI 1.000-1.010, p=0.033) were independently associated with postoperative hypoxemia. We identified several factors independently associated with postoperative lipiduria and hypoxemia in patients with fracture undergoing surgical intervention. Operation time was associated with both postoperative lipiduria and hypoxemia, and we recommend that patients with prolonged operation for fractures should be carefully monitored for clinical signs related to fat embolism syndrome

Glutamate regulates the expression of apoptosis-related genes and triggers the apoptosis of fibroblasts in rotator cuff tendons. Subacromial bursitis is always accompanied by symptomatic rotator cuff tear (RCT). However, no study has been reported on the presence of glutamate in subacromial bursa and on its involvement of shoulder pain in patients who had RCT. The purposes of this study were to determine whether the glutamate expression in subacromial bursa is associated with the presence of RCT and with the severity of shoulder pain accompanying RCT. Subacromial bursal tissues were harvested from patients who underwent arthroscopic rotator cuff tendon repair or glenoid labral repair with intact rotator cuff tendon. Glutamate tissue concentrations were measured, using a glutamate assay kit. Expressions of glutamate and its receptors in subacromial bursae were histologically determined. The sizes of RCT were determined by arthroscopic findings, using the DeOrio and Cofield classification. The severity of shoulder pain was determined, using visual analog scale (VAS). Any associations between glutamate concentrations and the size of RCT were evaluated, using logistic regression analysis. The correlation between glutamate concentrations and the severity of pain was determined, using the Pearson correlation coefficient. Differences with a probability <0.05 were considered statistically significant. Glutamate concentrations showed significant differences between the torn tendon group and the intact tendon group (P = 0.009). Concentrations of glutamate significantly increased according to increases in tear size (P < 0.001). In histological studies, the expressions of glutamate and of its ionotropic and metabotropic receptors have been confirmed in subacromial bursa. Glutamate concentrations were significantly correlated with pain on VAS (Rho=0.56 and P =0.01). The expression of glutamate in subacromial bursa is significantly associated with the presence of RCT and significantly correlated with its accompanying shoulder pain. Acknowledgements: This research was supported by the Basic Science Research Program, through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2015R1D1A3A01018955 and 2017R1D1A1B03035232)

Determine the prevalence, etiologies, and risk factors of unplanned return to the OR (UROR) in adult orthopaedic trauma patients. Retrospective review of a trauma prospective registry from 2014 – 2019 at a Level 1 academic hospital. An UROR was defined as a patient returning to OR unexpectedly following a planned definitive surgery to either readdress the presenting diagnosis or address a complication arising from the index procedure. Univariate and multivariate logistic regression was performed comparing those patients with an UROR versus those without. A total of 1568 patients were reviewed. The rate of UROR was 9.8% (153 patients). Symptomatic implant was the leading cause of UROR (60%). Other significant UROR causes were infection (15%) and implant failure (9%). The median time between index procedure and UROR was 301 days. For the univariate and multivariate analysis, open fracture (p< 0.05), fracture complexity (p<0.01), and weekend procedure (p< 0.01) were all associated with increased risk of UROR. All other variables were not statistically significant for any associations. Those patients with an UROR for reasons other than symptomatic implants were more likely to have polyorthopaedic injuries (p < 0.05), ISS > 15 (p < 0.05), osteoporosis (p < 0.01), ICU status (p < 0.05), psychiatric history (p < 0.05), compartment syndrome (p < 0.05), neurovascular injury (p < 0.01), open fracture (p < 0.05), and fracture complexity (p < 0.05). The rate of UROR in the orthopaedic trauma patient population is 10%. Most of these cases are due to implant-related issues. UROR for reasons other than symptomatic implants tend to be polytraumatized patients with higher-energy injuries, multiple complex fractures, and associated soft tissue injuries. Future focus on improved implant development and treatments for polytraumatized patients with complex fractures is warranted to decrease a relatively high UROR rate in orthopaedic trauma

Quantitative ultrasound (QUS) is a promising tool to estimate bone structure characteristics and predict fragile fracture. The aim of this pilot cross-sectional study was to evaluate the performance of a multi-channel residual network (MResNet) based on ultrasonic radiofrequency (RF) signal to discriminate fragile fractures retrospectively in postmenopausal women. Methods. RF signal and speed of sound (SOS) were obtained using an axial transmission QUS at one‐third distal radius for 246 postmenopausal women. Based on the involved RF signal, we conducted a MResNet, which combines multi-channel training with original ResNet, to classify the high risk of fragility fractures patients from all subjects. The bone mineral density (BMD) at lumber, hip and femoral neck acquired with DXA was recorded on the same day. The fracture history of all subjects in adulthood were collected. To assess the ability of the different methods in the discrimination of fragile fracture, the odds ratios (OR) calculated using binomial logistic regression analysis and the area under the receiver operator characteristic curves (AUC) were analyzed. Results. Among the 246 postmenopausal women, 170 belonged to the non-fracture group, 50 to the vertebral group, and 26 to the non-vertebral fracture group. MResNet was discriminant for all fragile fractures (OR = 2.64; AUC = 0.74), for Vertebral fracture (OR = 3.02; AUC = 0.77), for non-vertebral fracture (OR = 2.01; AUC = 0.69). MResNet showed comparable performance to that of BMD of hip and lumbar with all types of fractures, and significantly better performance than SOS all types of fractures. Conclusions. the MResNet model based on the ultrasonic RF signal can significantly improve the ability of QUS device to recognize previous fragile fractures. Moreover, the performance of the proposed model modified by age, weight, and height is further optimized. These results open perspectives to evaluate the risk of fragile fracture applying a deep learning model to analyze ultrasonic RF signal

Summary Statement. In a retrospective study, FE-based bone strength from CT data showed a greater ability than aBMD to discriminate proximal femur fractures versus controls. Introduction. Personalised Finite Element (FE) models from Computed Tomography (CT) data are superior to bone mineral density (BMD) in predicting proximal femoral strength in vitro [Cody, 1999]. However, results similar to BMD were obtained in vivo, in retrospective classification of generic prevalent fractures [Amin, 2011] and in prospective classification of femoral fractures [Orwoll, 2009]. The aim of this work is to test, in a case-control retrospective study, the ability of a different, validated FE modelling procedure [Schileo, 2008] to: (i) discriminate between groups of proximal femoral fractures and controls; (ii) individually classify fractures and controls. Patients & Methods. 55 women (22 incident low-trauma proximal femur fractures and 33 controls) were enrolled in 3 clinical centres in Emilia Romagna region, Italy. All received a full femoral CT and DXA exams (in acute conditions for fractured cases) with a standardised protocol. Femoral neck aBMD was measured from DXA. FE models were built from CT (right femur for controls, intact for fractured) [Schileo, 2008]. Differently from existing works, FE strength was calculated for a range of 12 physiological directions of hip joint reactions [Bergmann, 2001] and 10 fall directions [Grassi, 2012]. Bone strength (in stance and fall) was the minimum load inducing on the femoral neck surface an elastic principal strain value greater than the yield limit [Bayraktar, 2004]. Fracture classification was analysed through logistic regressions and AUC of ROC curves. Results. Mean FE strength and aBMD were significantly lower in the fractured than in the control group (33%, p<0.0001 for strength; 12% p=0.01 for aBMD). Logistic regression on single variables. All classifiers were significant (p<0.001, AUC=0.88 for both stance and fall FE strength, p=0.02, AUC=0.72 for aBMD). The statistical power of the logistic regressions [Vaeth, 2004] was >0.9 for FE strength, 0.86 for aBMD. Logistic regressions on multiple variables. Only FE strength was retained significant (p<0.001, AUC=0.88) when including aBMD in the regression. Adding age to the logistic regression, FE strength and age (but not aBMD) remained significant, with AUC=0.95. Discussion. FE strength could discriminate the fractured group better than aBMD and than [Keyak, 2011]. FE strength was a better fracture classifier than aBMD, and obtained AUC values slightly higher than [Amin, 2011; Orwoll, 2009]. The high statistical power mildens the small sample numerosity. Cases and controls were not age matched, but FE strength and age were found to be independent classifiers. In conclusion the proposed FE method was superior to aBMD in the classification of proximal femoral fractures

Open tibial fractures can be difficult to manage, with a range of factors that could affect treatment and outcome. We present a large cohort of patients, and analyse which factors have significant associations with infection outcome. Elucidation will allow clinicians to strive for treatment optimisation, and patients to be advised on likely complications. Open tibia fractures treated at a major trauma centre between 2015-2021 were included. Mean age at injury was 55.4 (range 13-102). Infection status was categorized into no infection, superficial infection, and osteomyelitis. Age, mode of injury, polytrauma, fibula status, Gustilo-Anderson (GA) classification, wound contamination, time from injury to: first procedure/definitive plastics procedure/definitive fixation, type of definitive fixation, smoking and diabetic status, and BMI, were collected. Multicollinearity was calculated, with highly correlated factors removed. Multinomial logistic regression was performed. Chi Squared testing, with Post Hoc Bonferroni correction was performed for complex categorical factors. Two hundred forty-four patients with open tibial fractures were included. Forty-five developed superficial infection (18.4%), and thirty-nine developed osteomyelitis (16.0%). Polytrauma, fibula status, and type of definitive fixation were excluded from the multivariate model due to strong multicollinearity with other variables. With reference to the non-infected outcome; superficial infection patients had higher BMI (p<0.01), higher GA grade (p<0.01), osteomyelitis patients had longer time to definitive fixation (p=0.049) and time to definitive plastics procedure (p=0.013), higher GA grade (p<0.01), and positive wound contamination(p=0.015). Poc hoc analysis showed “no infection” was positively associated with GA-I (p=0.029) and GA-II (p<0.01), and negatively associated with GA-IIIC (p<0.01). Osteomyelitis was positively associated with GA-IIIc (p<0.01). This study investigated the associations between the injury and presentation factors that may affect infection outcome. The variables highlighted are the factors clinicians should give extra consideration to when treating cases, and take preventative measures to optimize treatment and mitigate infection risk

With the coronavirus disease 2019 (COVID-19) pandemic, remote working has been ubiquitously implemented to reduce disease transmission via minimization of in-person interactions. Low back pain (LBP) is the first cause of disability worldwide and is frequently reported by workers with sedentary occupations. This cross-sectional study aimed to assess the role of remote working in a population of adults affected by LBP through an online questionnaire. We enrolled 136 teleworkers affected by LBP. A total of 101 responses were received and 93 suitable questionnaires were included in the final analysis. Demographic data, remote working features and tasks, and LBP burden were analysed. The psychological burden of remote working was evaluated with the World Health Organization Five Well-Being Index (WHO-5) and the Patient Health Questionnaire-2 (PHQ-2). LBP severity was evaluated using a visual analog scale (VAS). LBP-related disability was assessed using the Oswestry Disability Index (ODI). The effect of LBP on working capacity was examined with the Occupational Role Questionnaire (ORQ). Independent risk factors related to LBP worsening were identified using a multivariate logistic regression model. LBP severity was significantly higher compared to previous in-person working (p<0.0001) as well as average weekly work hours (p<0.001). Furthermore, the risk of LBP deterioration was associated with being divorced (OR: 4.28, 95% CI: 1.27-14.47; p=0.019) or living with others (OR: 0.24, 95% CI: 0.07-0.81; p=0.021), higher ill-being (OR: 0.91, 95% CI: 0.83-0.99; p=0.035) and depression scores (OR: 1.38, 95% CI: 1.00-1.91; p=0.048), as well as having reported unchanged (OR: 0.22, 95% CI: 0.08-0.65; p=0.006) or decreased job satisfaction (OR: 0.16, 95% CI: 0.05-0.54; p=0.003) and increased stress levels (OR: 3.00, 95% CI: 1.04-8.65; p=0.042). These findings highlight key factors to consider for improving remote workers’ physical and mental wellbeing and decrease their LBP burden

A hot swollen joint is a commonly encountered condition in clinical practice. With a broad range of differentials, septic arthritis (SA) is perhaps one of the most concerning. Treated by culture-specific antibiotics and arthroscopic lavage, some patients require multiple washouts. We aimed to determine:. (1) What are the risk factors for development of SA?. (2) What are the risk factors for repeat washout in SA patients?. (3) What are the important clinical differences between a periprosthetic joint infection (PJI) and SA cohort?. All patients presenting to the emergency department, orthopaedic, and rheumatology clinics between January 2020 to January 2021 with a hot, swollen joint were retrospectively evaluated. Patients with previous trauma on the ipsilateral joint, with data missing from their medical records in any of the variables required for analysis, <24 months follow-up were excluded. Variables of interest in the three-month period preceding the diagnosis of SA were compared between SA and non-SA patients. Factors with a p-value of p<0.100 in univariate analysis were included in a stepwise multivariate logistic regression model. Similar analyses were performed to compare SA patients with multiple washouts with those needing one washout. Demographical and clinical data for PJI patients were collected to delineate important differences with SA cohort. 211 patients were included (SA:28;PJI:24;pseudogout:32;gout:26;others:101). Multivariate analysis showed rheumatoid arthritis (RA), skin infection, and liver disease were risk factors for SA. Amongst patients with septic arthritis, multivariate analysis showed that WBC levels above normal limits (3.6-10.5×109 cells/L) and RA were risk factors for multiple washouts. Between the SA and PJI cohorts, BMI (p=0.002) was significantly lower in the former, whilst WBC level (p=0.023) and CRP (p<0.0001) was significantly higher in the former. Early diagnosis of septic arthritis requires understanding the risk factors, namely RA, skin infection, and liver disease. Considering PJI and septic arthritis as the same entity can lead to wrong clinical judgement, and clinicians should be aware of important differences. We believe that the models in this study are of prognostic value to clinicians who are presented with the common presenting compliant of a hot swollen joint

Anterior approach total hip arthroplasty (AA-THA) has a steep learning curve, with higher complication rates in initial cases. Proper surgical case selection during the learning curve can reduce early risk. This study aims to identify patient and radiographic factors associated with AA-THA difficulty using Machine Learning (ML). Consecutive primary AA-THA patients from two centres, operated by two expert surgeons, were enrolled (excluding patients with prior hip surgery and first 100 cases per surgeon). K- means prototype clustering – an unsupervised ML algorithm – was used with two variables - operative duration and surgical complications within 6 weeks - to cluster operations into difficult or standard groups. Radiographic measurements (neck shaft angle, offset, LCEA, inter-teardrop distance, Tonnis grade) were measured by two independent observers. These factors, alongside patient factors (BMI, age, sex, laterality) were employed in a multivariate logistic regression analysis and used for k-means clustering. Significant continuous variables were investigated for predictive accuracy using Receiver Operator Characteristics (ROC). Out of 328 THAs analyzed, 130 (40%) were classified as difficult and 198 (60%) as standard. Difficult group had a mean operative time of 106mins (range 99–116) with 2 complications, while standard group had a mean operative time of 77mins (range 69–86) with 0 complications. Decreasing inter-teardrop distance (odds ratio [OR] 0.97, 95% confidence interval [CI] 0.95–0.99, p = 0.03) and right-sided operations (OR 1.73, 95% CI 1.10–2.72, p = 0.02) were associated with operative difficulty. However, ROC analysis showed poor predictive accuracy for these factors alone, with area under the curve of 0.56. Inter-observer reliability was reported as excellent (ICC >0.7). Right-sided hips (for right-hand dominant surgeons) and decreasing inter-teardrop distance were associated with case difficulty in AA-THA. These data could guide case selection during the learning phase. A larger dataset with more complications may reveal further factors

Revision knee arthroplasty is a complex procedure with the number and cost of knee revision procedures performed per year expected to rise. Few studies have examined adverse events following revision arthroplasty. The objective of this study was to determine rates of serious adverse events in patients undergoing revision knee arthroplasty with consideration of the indication for revision (urgent versus elective indications) and to compare these with primary arthroplasty and re-revision arthroplasty. Patients undergoing primary knee arthroplasty were identified in the UK Hospital Episode Statistics. Subsequent revision and re-revision arthroplasty procedures in the same patients and same knee were identified. The primary outcome was 90-day mortality and a logistic regression model was used to investigate factors associated with 90-day mortality and secondary adverse outcomes including infection (undergoing surgery), pulmonary embolism, myocardial infarction, stroke. Urgent indications for revision arthroplasty were defined as infection or fracture, and all other indications were included in the elective indications cohort. 939,021 primary knee arthroplasty cases were included of which 40,854 underwent subsequent revision arthroplasty, and 9,100 underwent re-revision arthroplasty. Revision surgery for elective indications was associated with a 90-day rate of mortality of 0.44% (135/30,826; 95% CI 0.37-0.52) which was comparable to primary knee arthroplasty (0.46%; 4,292/939,021; 95% CI 0.44-0.47). Revision arthroplasty for infection, however, was associated with a much higher mortality of 2.04% (184/9037; 95% CI 1.75-2.35; odds ratio [OR] 3.54; 95% CI 2.81-4.46), as was revision for periprosthetic fracture at 5.25% (52/991; 95% CI 3.94-6.82; OR 6.23; 95% CI 4.39-8.85). Higher rates of pulmonary embolism, myocardial infarction, and stroke were also observed in the infection and fracture cohort. These findings highlight the burden of complications associated with revision knee arthroplasty. They will inform shared decision-making for patients considering revision knee arthroplasty for elective indications. Patients presenting with infection of a knee arthroplasty or a periprosthetic fracture are at very high risk of adverse events. It is important that acute hospital services and tertiary referral centres caring for these patients are appropriately supported to ensure appropriate urgency and an anticipation for increased care requirements

Fracture related infections (FRI) are debilitating complications of musculoskeletal trauma surgery that can result in permanent functional loss or amputation. This study aims to determine risk factors associated with FRI treatment failure, allowing clinicians to optimise them prior to treatment and identify patients at higher risk. A major trauma centre database was retrospectively reviewed over a six-year period. Of the 102 patients identified with a FRI (66 male, 36 female), 29.4% (n=30) had acute infections (onset <6 weeks post-injury), 34.3% (n=35) had an open fracture. Open fractures were classified using Gustilo-Anderson (GA) classification (type 2:n=6, type 3A:n=16, type 3B:n=10, type 3C:n=3). Patients with periprosthetic infections of the hip and knee joint, those without prior fracture fixation, soft tissue infections, diabetic foot ulcers, pressure sore infections, patients who died within one month of injury, <12 months follow-up were excluded. FRI treatment failure was defined as either infection recurrence, non-union, or amputation. Lifestyle, clinical, and intra-operative data were documented via retrospective review of medical records. Factors with a P-value of p<0.05 in univariate analysis were included in a stepwise multivariate logistic regression model. FRI treatment failure was encountered in 35.3% (n=36). The most common FRI site was the femoral shaft (16.7%; n=17), and 15.7% (n=16) presented with signs of systemic sepsis. 20.6% (n=21) had recurrent infection, 9.8% (n=10) had non-union, and 4.9% (n=5) required an amputation. The mean age at injury was 49.71 years old. Regarding cardiovascular risk factors, 37 patients were current smokers (36.3%), 31 patients were diabetics (30.4%), and 32 patients (31.4%) were obese (BMI≥30.0). Average follow-up time was 2.37 (range: 1.04-5.14) years. Risk factors for FRI treatment failure were BMI>30, GA type 3c, and implant retention. Given that FRI treatment in 35.3% (36/102) ended up in failure, clinicians need to take into account the predictive variables analysed in this study, and implement a multidisciplinary team approach to optimise these factors. This study could aid clinicians to redirect efforts to improve high risk patient management, and prompt future studies to trial adjuvant technologies for patients at higher risk of failure

Abstract. Objective. To estimate the effect of calcar collar separation on the likelihood of calcar collar contact during in vitro periprosthetic fracture. Methods. Three groups of six composite femurs were implanted with a collared cementless femoral stem. Neck resection was increased between groups (group 1 = normal, group 2 = 3mm additional, group 3 = 6mm additional), to simulate failure to obtain calcar collar contact. Prior to each trial, the distances between anterior (ACC) and posterior (PCC) collar and the calcar were measured. Periprosthetic fractures of the femur were simulated using a previously published technique. High speed video recording identified when collar to calcar contact (CCC) occurred. The ACC and PCC were compared between trials where the CCC was and was not achieved. Regression estimated the odds of failing to achieve CCC for a given ACC or PCC. Results. CCC was achieved prior to fracture in all cases in group one, 50% in group two and 0% in group three. The median (range) ACC for those trials where CCC was achieved was 0.40 (0.00, 3.37) mm versus 6.15 (3.06 to 6.88) mm, where CCC was not achieved (p <0.01). The median (range) PCC for those trials where CCC was achieved was 0.85 (0.00 to 3.71) mm versus 5.97 (2.23 to 7.46) mm, where CCC was not achieved (p <0.01). Binomial logistic regression estimated risk of failure to obtain CCC increased 3.8 fold (95% confidence interval 1.6 to 30.2, p <0.05) for each millimetre of PCC. Conclusions. Increased separation between collar and calcar reduced the likelihood of calcar collar contact during a simulated periprosthetic fracture of the femur. Surgeons should aim to achieve a calcar-collar distance of less than 1mm following implantation to ensure calcar collar contact during periprosthetic femoral fracture and to reduce the risk of fracture. Declaration of Interest. (a) fully declare any financial or other potential conflict of interest

Abstract. Objectives. Modular dual-mobility (MDM) constructs are used to reduce dislocation rates after total hip replacement (THR). They combine the advantages of dual mobility with the option of supplementary acetabular screw fixation in complex revision surgery. However, there are concerns about adverse reaction to metal debris (ARMD) as a result of fretting corrosion between the metal liner and shell. Methods. The aim of this systematic review was to find and review all relevant studies to establish the outcomes and risks associated with MDM hip replacement. All articles on MDM THRs in the Medline, EMBASE, CINAHL, Cochrane Library, and Prospero databases were searched. A total of 14 articles were included. A random intercept logistic regression model was used for meta-analysis, giving estimated mean values. Results. There were 6 cases of ARMD out of 1312 total. Estimated median incidence of ARMD from meta-analysis was 0.3% (95% CI 0.1 – 1.4%). Mean postoperative serum Cobalt was 0.81 μg/L (95% CI 0.33 – 1.29 μg/L), and Chromium was 0.77 μg/L (95% 0.35 – 1.19 μg/L), from 279 cases in 7 studies. Estimated median incidence of a serum cobalt or chromium ion measurement ≥1 μg/L was 7.9% (95% CI 3.5 – 16.8%), and ≥7 μg/L was 1.8% (95% CI 0.7 – 4.2%). Conclusions. ARMD is a rare but significant complication following total hip replacement using a MDM construct. Its incidence appears higher than that reported in non-metal-on-metal (MoM) hip replacements but lower than that of MoM hip replacements. MDM hip replacements are associated with raised serum metal ion levels postoperatively, but there was no correlation with worse clinical hip function within studies. Studies were poor quality and at high risk of confounding. Pending further work, MDM constructs should be used with caution, reserved for select cases at particularly high risk of dislocation. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

Objectives. Modular dual-mobility (MDM) constructs are used to reduce dislocation rates after total hip replacement (THR). They combine the advantages of dual mobility with the option of supplementary acetabular screw fixation in complex revision surgery. However, there are concerns about adverse reaction to metal debris (ARMD) as a result of fretting corrosion between the metal liner and shell. Methods: The aim of this systematic review was to find and review all relevant studies to establish the outcomes and risks associated with MDM hip replacement. All articles on MDM THRs in the Medline, EMBASE, CINAHL, Cochrane Library, and Prospero databases were searched. A total of 14 articles were included. A random intercept logistic regression model was used for meta-analysis, giving estimated average values. Results: There were 6 cases of ARMD out of 1312 total. Estimated median incidence of ARMD from meta-analysis was 0.3% (95% CI 0.1 – 1.4%). Mean postoperative serum Cobalt was 0.81 μg/L (95% CI 0.33 – 1.29 μg/L), and Chromium was 0.77 μg/L (95% 0.35 – 1.19 μg/L), from 279 cases in 7 studies. Estimated median incidence of a serum cobalt or chromium ion measurement ≥1 μg/L was 7.9% (95% CI 3.5 – 16.8%), and ≥7 μg/L was 1.8% (95% CI 0.7 – 4.2%). Conclusions: ARMD is a rare but significant complication following total hip replacement using a MDM construct. Its incidence appears higher than that reported in non-metal-on-metal (MoM) hip replacements but lower than that of MoM hip replacements. MDM hip replacements are associated with raised serum metal ion levels postoperatively, but there was no correlation with worse clinical hip function within studies. Studies were poor quality and at high risk of confounding. Pending further work, MDM constructs should be used with caution, reserved for select cases at particularly high risk of dislocation

The CCI mobile bearing ankle implant used at our orthopedic department 2010–2013, was abandoned due to failures and findings of bone loss at revision. The aim of this study was to a) Determine our true revision rate, b) Investigate accuracy of measuring prevalence, size and location of periprosthetic bone cysts through X-ray and CT and c) Relate these findings to implant alignment and patient reported outcome measurements (PROMs). 51 primary surgeries were performed, prior to this study 8 had been revised. Out of 43 un-revised patients, 36 were enrolled and underwent evaluation with metal artefact reduction CT-scans and conventional X-ray. They filled out 3 PROMs; SEFAS, SF-12, EQ-5D. Cyst volume larger than 0.1 ml was measured using VITREA volume tools for CT-scans and calculation of spherical volume for X-rays; using AP- and lateral projections. Location of lesions was recorded, according to their position relative to the implant. Medial-/lateral- and anterior-/posterior tilt of the implant parts was measured using IMPAX built in measuring tools, applied to AP- and lateral X-ray projection. The relation between lesions location and alignment of components was analyzed by logistic regression. Bias and ICC estimation between CT and X-ray was analyzed by mixed effect model. Log transformation was used to fit the normal distribution assumption. PROMs association to osteolytic volume was analyzed by linear- and logistic regression. P-values of 0.05 were considered statistically significant. Finding large osteolytic lesions caused 4 additional patients to undergo revision and 7 are being monitored due to high risk of failure. Of the original 51 implants 14 have been revised. 8 cases because of osteolytic lesions and aseptic loosening (true revisions w. exchange of components or bone transplants), 3 periprosthetic fractures (2 non-traumatic fractures) and 3 cases of exostosis. The 3- and 5 year revision rate was 14% and 16% for true revisions and 17% and 27% overall. Cystic lesions were found in 81% of participants. Total cyst-volume was on average 13% larger on X-ray, however this difference was not significant (p = 0.55), with intraclass correlation being 0.66. Total cystic volume was not significantly related to PROM-scores (P 0.16–0.5). Location of cysts showed association with alignment of components (P 0.02–0.08). Mean tibia component anterior tilt was 89 degrees (SD 4). Mean medial tilt was 91 degrees (SD 3) for the tibial and 90 degrees (SD 4) for the talar component. The implant investigated performs below standard, compared to public registries. 1, 2. that report overall 5 year revision rates at 5 – 6.5%. We obtained larger measurements from X-rays than CT, unlike previous studies comparing these modalities. Cysts were common and large. Correlation between lesion location and alignment of implant, with valgus and anterior tilt of components causing more lesions in adjacent zones, may suggest a link between implant failure and alignment of components

Introduction. Patellofemoral pain and instability can be quantified by using the tibial tuberosity to trochlea groove (TT-TG) distance with more than or equal to 20mm considered pathological requiring surgical correction. Aim of this study is to determine if knee joint rotation angle is predictive of a pathological TT-TG. Methods. One hundred limbs were imaged from the pelvis to the foot using Computer Tomography (CT) scans in 50 patients with patellofemoral pain and instability. The TT-TG distance, femoral version, tibial torsion and knee joint rotation angle ((KJRA) were measured. Limbs were separated into pathological and non-pathological TT-TG. Significant differences in the measured angles between the pathological and non-pathological groups were estimated using the t test. The inter- and intraobserver variability of the measurement was performed. Logistic regression analysis was used to find the best combination of rotational angle predictors for a pathological TT-TG. Results. The intraclass correlation coefficients for inter- and intraobserver variability of the measured parameters was higher than 0.94 for all measurements. A statistically significant difference (P=0.024) was found between the KJRA between the pathological (mean=10.6, SD=7.79 degrees) and the non-pathological group (mean=6.99, SD=5.06 degrees). Logistic regression analysis showed that both femoral version (P=0.03, OR = 0.95) and KJRA (P=0.004, OR=1.15) were, in combination, significant predictors of an abnormal TT-TG. Tibial torsion was not a significant predictor. Conclusion. The KJRA can be used as an alternative measurement when the TT-TG distance cannot be measured as in cases of severe trochlea dysplasia and may act as a surrogate for pathological TT-TG

Acute lateral ankle sprain accounts for 85% of sprains. The lateral sprain is associated with other ligament injuries e.g. medial and syndesmosis sprain. Long-term, approximately 20% of acute lateral sprains develop into chronic lateral ankle instability (CLAI) which includes persistent pain, and recurring ankle sprains. This study evaluated the grade of an ankle ligament injury by ultrasonography (US) and compared the findings to the outcome of patient-reported questionnaires. 48 subjects (18–40 years) diagnosed with an ankle sprain attended a clinical and US examination of ankle ligaments within two weeks after the sprain. Evaluation was done by US of acute lateral ligament injuries (ATFL, CFL), syndesmosis injury (AiTFL), and medial injury (dPT, TCt) only in participants with the positive clinical signs of medial injury. Participants were then mailed a questionnaire (PROMQ) every third month for a year. 29 women and 19 men participated with a mean age at 26.50 years. One-year follow-ups need to be analyzed further for final results. Temporary results include data based on the initial 26 patients: Two clinical signs statistically correlated. Multiple logistic regression analysis confirmed the results. Positive palpated tenderness AiTFL predicted with partial ruptured ATFL and reported pain during active plantar flexion of ankle predicted with normal CFL confirmed by the US. Patients with partial rupture of ATFL presented with tenderness at AiTFL point. Patients presenting with intact CFL reported pain during active plantar flexion. Compared to the US findings, the overall examinations were inconclusive in predicting ATFL, CFL, AiTFL, and medial ligament injuries