Metal-on-metal hip resurfacing is commonly performed for osteoarthritis in young active patients. We have observed cystic or solid masses, which we have called inflammatory pseudotumours, arising around these devices. They may cause soft-tissue destruction with severe symptoms and a poor outcome after revision surgery. The aim of this study was to determine the incidence of and risk factors for pseudotumours that are serious enough to require revision surgery. Since 1999, 1419 metal-on-metal hip resurfacings have been implanted by our group in 1224 patients; 1.8% of the patients had a revision for pseudotumour. In this series the Kaplan-Meier cumulative revision rate for pseudotumour increased progressively with time. At eight years, in all patients, it was 4% (95% confidence interval (CI) 2.2 to 5.8). Factors significantly associated with an increase in revision rate were female gender (p < 0.001), age under 40 (p = 0.003), small components (p = 0.003), and dysplasia (p = 0.019), whereas implant type was not (p = 0.156). These factors were inter-related, however, and on fitting a Cox proportional hazard model only gender (p = 0.002) and age (p = 0.024) had a significant independent influence on revision rate; size nearly reached significance (p = 0.08). Subdividing the cohort according to significant factors, we found that the revision rate for pseudotumours in men was 0.5% (95% CI 0 to 1.1) at eight years wheras in women over 40 years old it was 6% (95% CI 2.3 to 10.1) at eight years and in women under 40 years it was 13.1% at six years (95% CI 0 to 27) (p < 0.001). We recommend that resurfacings are undertaken with caution in women, particularly those under 40 years of age but they remain a good option in young men. Further work is required to understand the aetiology of pseudotumours so that this complication can be avoided

Aims. The role of high tibial osteotomy (HTO) is being questioned by the use of unicompartmental knee arthroplasty (UKA) in the treatment of medial compartment femorotibial osteoarthritis. Our aim was to compare the outcomes of revision HTO or UKA to a total knee arthroplasty (TKA) using computer-assisted surgery in matched groups of patients. Patients and Methods. We conducted a retrospective study to compare the clinical and radiological outcome of patients who underwent revision of a HTO to a TKA (group 1) with those who underwent revision of a medial UKA to a TKA (group 2). All revision procedures were performed using computer-assisted surgery. We extracted these groups of patients from our database. They were matched by age, gender, body mass index, follow-up and pre-operative functional score. The outcomes included the Knee Society Scores (KSS), radiological outcomes and the rate of further revision. Results. There were 20 knees in 20 patients in each group. The mean follow-up was 4.1 years (2 to 18.7). The mean total KSS at last follow-up was 185.7 (standard deviation (. sd. ) 5) in group 1 compared with 176.5 (. sd. 11) for group 2 (p = 0.003). The mean hip-knee-ankle angle was 180.2° (. sd. 3.2°) in group 1 and 179.0° (. sd. 2.2°) in group 2. No revision was required. Conclusion. We found that good functional and radiological outcomes followed revision of both HTO and UKA to TKA. Revision of HTO showed significantly better functional outcomes. These results need to be further investigated by a prospective randomised controlled trial involving a larger group of patients. Cite this article: Bone Joint J 2016;98-B:1620–4

Objectives. The primary purpose of this meta-analysis was to determine whether statin usage could reduce the risk of glucocorticoid-related osteonecrosis in animal models. Methods. A systematic literature search up to May 2015 was carried out using the PubMed, Ovid, EBM reviews, ISI Web of Science, EBSCO, CBM, CNKI databases with the term and boolean operators: statins and osteonecrosis in all fields. Risk ratio (RR), as the risk estimate of specific outcome, was calculated along with 95% confidence intervals (CI). The methodological quality of individual studies was assessed using a quantitative tool based on the updated Stroke Therapy Academic Industry Roundtable (STAIR) recommendations. Results. A total of 11 eligible studies were included according to predetermined criteria. The pooled data demonstrated that animals with statin usage, either alone or combined with other treatments, were at a decreased risk of developing glucocorticoid-related osteonecrosis (RR = 2.06, 95% confidence interval (CI) 1.71 to 2.50). Moreover, subgroup analysis revealed that compared with statins alone, statins combined with other treatments significantly decreased the risk of osteonecrosis (RR = 1.23, 95% CI 1.02 to 1.47). However, we could find no significant risk difference for different gender, or for different time points. Conclusions. The present study suggests that statins combined with other treatments are efficient in preventing the development of glucocorticoid-related osteonecrosis in animals. These results might shed light on clinical practice when glucocorticoids are prescribed, and could be further investigated in high-quality clinical trials. Cite this article: Z. Yang, H. Liu, D. Li, X. Xie, T. Qin, J. Ma, P. Kang. The efficacy of statins in preventing glucocorticoid-related osteonecrosis in animal models: A meta-analysis. Bone Joint Res 2016;5:393–402. DOI: 10.1302/2046-3758.59.2000500

Aims. Risk of revision following total knee arthroplasty (TKA) is higher in patients under 55 years, but little data are reported regarding non-revision outcomes. This study aims to identify predictors of dissatisfaction in these patients. Patients and Methods. We prospectively assessed 177 TKAs (157 consecutive patients, 99 women, mean age 50 years; 17 to 54) from 2008 to 2013. Age, gender, implant, indication, body mass index (BMI), social deprivation, range of movement, Kellgren-Lawrence (KL) grade of osteoarthritis (OA) and prior knee surgery were recorded. Pre- and post-operative Oxford Knee Score (OKS) as well as Short Form-12 physical (PCS) and mental component scores were obtained. Post-operative range of movement, complications and satisfaction were measured at one year. Results . Overall, 44 patients with 44 TKAs (24.9%) under 55 years of age were unsure or dissatisfied with their knee. Significant predictors of dissatisfaction on univariate analysis included: KL grade 1/2 OA (59% dissatisfied), poor pre-operative OKS, complications, poor improvements in PCS and OKS and indication (primary OA 19% dissatisfied, previous meniscectomy 41%, multiply operated 42%, other surgery 29%, BMI > 40 kg/m. 2. 31%, post-traumatic OA 45%, and inflammatory arthropathy 5%). Poor pre-operative OKS, poor improvement in OKS and post-operative stiffness independently predicted dissatisfaction on multivariate analysis. Conclusion. Patients receiving TKA younger than 55 years old should be informed about the increased risks of dissatisfaction. Offering TKA in KL 1/2 is questionable, with a dissatisfaction rate of 59%. Cite this article: Bone Joint J 2016;98-B:1625–34

Aims. Advocates of debridement, antibiotics and implant retention (DAIR) in hip periprosthetic joint infection (PJI) argue that a procedure not disturbing a sound prosthesis-bone interface is likely to lead to better survival and functional outcome compared with revision. This case-control study aims were to compare outcome of DAIRs for infected primary total hip arthroplasty (THA) with outcomes following primary THA and two-stage revision of infected primary THAs. Patients and Methods. We retrospectively reviewed all DAIRs, performed for confirmed infected primary hip arthropasty (n = 82) at out institution, between 1997 and 2013. Data recorded included full patient information and type of surgery. Outcome measures included complications, mortality, implant survivorship and functional outcome. Outcome was compared with two control groups matched for gender and age; a cohort of primary THAs (n = 120) and a cohort of two-stage revisions for infection (n = 66). Results. Mean age at DAIR was 69 years (33 to 87) and mean follow-up was eight years (2 to 17; standard deviation (. sd). 5). A total of 52 (63%) of DAIRs were for early PJI (less than six weeks). Greater success in the eradication of infection with DAIR was identified with early PJI, comprising an interval less than a week between onset of symptoms and exchange of modular components with the DAIR procedure. Eradication of infection, complications and re-operation rates were similar in the DAIR and two-stage revision groups. For hips with successful eradication of infection with DAIR, the five-year survival (98%; 95% confidence interval (CI) 94 to 100) was similar to the primary THA group (98%; 95% CI 95 to 100) (n = 43; p = 0.3). The DAIR group had inferior mean Oxford Hip Scores (OHS) (38; 12 to 48) compared with the primary THA group (42; 15 to 48) (p = 0.02) but a significantly better mean OHS compared with the two-stage revision group (31; 0 to 48) (p = 0.008). Patients who required only one DAIR for eradication of infection had a similar mean OHS (41; 20 to 48) to the primary THA group (p = 0.2). Conclusion. The DAIR procedure is associated with a similar complication rate and ability to eradicate infection as two-stage revision. This study emphasises the need for exchange of modular components for improved chances of eradication of infection. This is the first study showing that DAIR is better than a two-stage revision regarding functional outcome. Cite this article: Bone Joint J 2017;99-B:614–22

Aims. To evaluate whether an ultra-low-dose CT protocol can diagnose selected limb fractures as well as conventional CT (C-CT). Patients and Methods. We prospectively studied 40 consecutive patients with a limb fracture in whom a CT scan was indicated. These were scanned using an ultra-low-dose CT Reduced Effective Dose Using Computed Tomography In Orthopaedic Injury (REDUCTION) protocol. Studies from 16 selected cases were compared with 16 C-CT scans matched for age, gender and type of fracture. Studies were assessed for diagnosis and image quality. Descriptive and reliability statistics were calculated. The total effective radiation dose for each scanned site was compared. Results. The mean estimated effective dose (ED) for the REDUCTION protocol was 0.03 milliSieverts (mSv) and 0.43 mSv (p < 0.005) for C-CT. The sensitivity (Sn), specificity (Sp), positive predictive value (PPV) and negative predictive value (NPV) of the REDUCTION protocol to detect fractures were 0.98, 0.89, 0.98 and 0.89 respectively when two occult fractures were excluded. Inter- and intra-observer reliability for diagnosis using the REDUCTION protocol (κ = 0.75, κ = 0.71) were similar to those of C-CT (κ = 0.85, κ = 0.82). Using the REDUCTION protocol, 3D CT reconstructions were equivalent in quality and diagnostic information to those generated by C-CT (κ = 0.87, κ = 0.94). Conclusion. With a near 14-fold reduction in estimated ED compared with C-CT, the REDUCTION protocol reduces the amount of CT radiation substantially without significant diagnostic decay. It produces images that appear to be comparable with those of C-CT for evaluating fractures of the limbs. Cite this article: Bone Joint J 2016;98-B:1668-73

The epidemiological data and intra-operative findings from 260 consecutive arthroscopically-diagnosed acetabular labral tears seen over a ten-year period were analysed. Radiographs of 128 of these patients were assessed for dysplasia using established radiological parameters. Patients with acetabular dysplasia were then compared against those without in order to identify any differences in gender, age, the side of the tear, the pattern of the tear, the number of quadrants involved, the quadrant preference and the prevalence of intra-articular comorbidity. Dysplasia was found in 46% (59 of 128) of the hips. No significant differences existed between the dysplastic and non-dysplastic subgroups as regards gender distribution, the side of the lesion, the number of quadrants involved or the distribution of tears among the quadrants. However, tears associated with dysplasia were diagnosed in an older age group, had a different pattern and were associated with a much higher prevalence of osteoarthritis

Nerve palsy is a well-described complication following total hip arthroplasty, but is highly distressing and disabling. A nerve palsy may cause difficulty with the post-operative rehabilitation, and overall mobility of the patient. Nerve palsy may result from compression and tension to the affected nerve(s) during the course of the operation via surgical manipulation and retractor placement, tension from limb lengthening or compression from post-operative hematoma. In the literature, hip dysplasia, lengthening of the leg, the use of an uncemented femoral component, and female gender are associated with a greater risk of nerve palsy. We examined our experience at a high-volume, tertiary care referral centre, and found an overall incidence of 0.3% out of 39 056 primary hip arthroplasties. Risk factors found to be associated with the incidence of nerve palsy at our institution included the presence of spinal stenosis or lumbar disc disease, age younger than 50, and smoking. If a nerve palsy is diagnosed, imaging is mandatory and surgical evacuation or compressive haematomas may be beneficial. As palsies are slow to recover, supportive care such as bracing, therapy, and reassurance are the mainstays of treatment. Cite this article: Bone Joint J 2017;99-B(1 Supple A):46–9

Aims. We investigated changes in the axial alignment of the ipsilateral hip and knee after total hip arthroplasty (THA). . Patients and Methods. We reviewed 152 patients undergoing primary THA (163 hips; 22 hips in men, 141 hips in women) without a pre-operative flexion contracture. The mean age was 64 years (30 to 88). The diagnosis was osteoarthritis (OA) in 151 hips (primary in 18 hips, and secondary to dysplasia in 133) and non-OA in 12 hips. A posterolateral approach with repair of the external rotators was used in 134 hips and an anterior approach in 29 hips. We measured changes in leg length and offset on radiographs, and femoral anteversion, internal rotation of the hip and lateral patellar tilt on CT scans, pre- and post-operatively. . Results. The mean internal rotation increased by 11° (-15° to 46°) and was associated with underlying disease (OA), pre-operative range of internal rotation, gender, surgical approach, leg lengthening, and change of femoral anteversion (adjusted R. 2. : 0.253, p < 0.001). The mean lateral patellar tilt increased by 4° (-5° to 14°) and was associated with age, leg lengthening, and increment of hip internal rotation (adjusted R. 2. : 0.193, p < 0.001). Conclusion. Both internal rotation of the hip at rest and lateral patellar tilt are increased after THA. Changes in rotation after THA may affect gait, daily activities, the rate of dislocation of the hip, and ipsilateral knee pain. Take home message: Internal rotation of the hip at rest and lateral patellar tilt increase after THA. Cite this article: Bone Joint J 2016;98-B:349–58

Aims. Total wrist arthrodesis (TWA) produces a spectrum of outcomes. We investigated this by reviewing 77 consecutive TWA performed for inflammatory and post-traumatic arthropathies, wrist instability and as a salvage procedure. . Patients and Methods. All operations were performed by a single surgeon using a specifically designed pre-contoured dorsally applied non-locking wrist arthrodesis plate at a single centre. . Results. Median post-operative Buck-Gramcko Lohman (BGL), Disabilities of the Arm, Shoulder and Hand and Patient Rated Wrist Evaluation scores at six years (interquartile range (IQR) 3 to 11) were 9 (IQR = 6 to 10), 19 (IQR = 7 to 45) and 13 (IQR = 1 to 31) respectively. Polyarticular inflammatory arthritis and female gender were associated with poorer patient-reported outcomes, although the effect of gender was partly explained by higher rates of inflammatory disease among women. Return to work was negatively influenced by workers’ compensation and non-inflammatory wrist pathology. There was no difference in complication rates for inflammatory and non-inflammatory indications. . Take home message: Polyarticular inflammatory arthritis is a risk factor for adverse patient-reported outcomes in TWA. Furthermore, when compared with patients without inflammatory arthritis, dorsally applied pre-contoured plates can be used for wrist arthrodesis in patients with inflammatory arthritis without an increased risk of complications. Cite this article: Bone Joint J 2016;98-B:647–53

We validated the North American Spine Society (NASS) outcome-assessment instrument for the lumbar spine in a computerised touch-screen format and assessed patients’ acceptance, taking into account previous computer experience, age and gender. Fifty consecutive patients with symptomatic and radiologically-proven degenerative disease of the lumbar spine completed both the hard copy (paper) and the computerised versions of the NASS questionnaire. Statistical analysis showed high agreement between the paper and the touch-screen computer format for both subscales (intraclass correlation coefficient 0.94, 95% confidence interval (0.90 to 0.97)) independent of computer experience, age and gender. In total, 55% of patients stated that the computer format was easier to use and 66% preferred it to the paper version (p < 0.0001 among subjects expressing a preference). Our data indicate that the touch-screen format is comparable to the paper form. It may improve follow-up in clinical practice and research by meeting patients’ preferences and minimising administrative work

Aims. The aim of this study was to identify risk factors for prosthetic joint infection (PJI) following total knee arthroplasty (TKA). . Patients and Methods. The New Zealand Joint Registry database was analysed, using revision surgery for PJI at six and 12 months after surgery as primary outcome measures. Statistical associations between revision for infection, with common and definable surgical and patient factors were tested. Results. A total of 64 566 primary TKAs have been recorded on the registry between 1999 and 2012 with minimum follow-up of 12 months. Multivariate analysis showed statistically significant associations with revision for PJI between male gender (odds ratio (OR) 1.85, 95% confidence interval (CI) 1.24 to 2.74), previous surgery (osteotomy (OR 2.45 95% CI 1.2 to 5.03), ligament reconstruction (OR 1.85, 95% CI 0.68 to 5.00)), the use of laminar flow (OR 1.6, 95% CI 1.04 to 2.47) and the use of antibiotic-laden cement (OR 1.93, 95% CI 1.19 to 3.13). There was a trend towards significance (p = 0.052) with the use of surgical helmet systems at six months (OR 1.53, 95% CI 1.00 to 2.34). Conclusion. These findings show that patient factors remain the most important in terms of predicting early PJI following TKA. Furthermore, we found no evidence that modern surgical helmet systems reduce the risk of PJI and laminar flow systems may actually increase risk in TKA. The use of this registry data assists the estimation of the risk of PJI for individual patients, which is important for both informed consent and the interpretation of infection rates at different institutions. . Take home message: Infection rates in TKA are related to both individual patient and surgical factors, and some modern methods of reducing infection may actually increase infection risk. . Cite this article: Bone Joint J 2016;98-B:334–40

Aims. To determine whether there is any difference in infection rate at 90 days between trauma operations performed in laminar flow and plenum ventilation, and whether infection risk is altered following the installation of laminar flow (LF). Patients and Methods. We assessed the impact of plenum ventilation (PV) and LF on the rate of infection for patients undergoing orthopaedic trauma operations. All NHS hospitals in England with a trauma theatre(s) were contacted to identify the ventilation system which was used between April 2008 and March 2013 in the following categories: always LF, never LF, installed LF during study period (subdivided: before, during and after installation) and unknown. For each operation, age, gender, comorbidity, socio-economic deprivation, number of previous trauma operations and surgical site infection within 90 days (SSI90) were extracted from England’s national hospital administrative Hospital Episode Statistics database. Crude and adjusted odds ratios (OR) were used to compare ventilation groups using hierarchical logistic regression. Subanalysis was performed for hip hemiarthroplasties. Results. A total of 803 065 trauma operations were performed during this time; 19 hospitals installed LF, 124 already had LF, 13 had PV and the type of ventilation was unknown in 28. Patient characteristics were similar between the groups. The rate of SSI90 was similar for always LF and PV (2.7% and 2.4%). For hemiarthroplasties of the hip, the rates of SSI90 were significantly higher for LF compared with PV (3.8% and 2.6%, OR 1.45, p = 0·001). Hospitals installing LF did not see any statistically significant change in the rate of SSI90. Conclusion. The results of this observational study imply that infection rate is similar when orthopaedic trauma surgery is performed in LF and PV, and is unchanged by installing LF in a previously PV theatre. Cite this article: Bone Joint J 2016;98-B:1262–9

Aims. Hemiarthroplasty of the hip is usually carried out through either a direct lateral or posterior approach. The aim of this prospective observational study was to determine any differences in patient-reported outcomes between the two surgical approaches. . Patients and Methods. From the Swedish Hip Arthroplasty Register we identified patients of 70 years and above who were recorded as having had a hemiarthroplasty during 2009. Only patients who had been treated with modern prostheses were included. A questionnaire was posted to those who remained alive one year after surgery. A total of 2118 patients (78% of those available) with a mean age of 85 years (70 to 102) returned the questionnaire. . Results. Patients who had undergone surgery through a posterior approach reported a higher health-related quality of life (HRQoL, EQ-5D mean 0.52 versus 0.47, p = 0.009), less pain (visual analogue scale mean 17 versus 19, p = 0.02) and greater satisfaction with the result of surgery (visual analogue scale mean 22 versus 24, p = 0.02) than those who had a direct lateral approach. However, after adjusting for age, gender, cognitive impairment and American Society of Anesthesiologists grade, no association was found between surgical approach and HRQoL, residual pain or patient satisfaction. Take home message: The surgical approach for hemiarthroplasty does not seem to affect the patient-perceived HRQoL, residual pain or patient satisfaction one year after surgery on elderly patients. The choice of approach should be based on other factors, such as the risk of dislocation. Cite this article: Bone Joint J 2016;98-B:542–7

The objective of this study was to validate the efficacy of Takeuchi classification for lateral hinge fractures (LHFs) in open wedge high tibial osteotomy (OWHTO). In all 74 osteoarthritic knees (58 females, 16 males; mean age 62.9 years, standard deviation 7.5, 42 to 77) were treated with OWHTO using a TomoFix plate. The knees were divided into non-fracture (59 knees) and LHF (15 knees) groups, and the LHF group was further divided into Takeuchi types I, II, and III (seven, two, and six knees, respectively). The outcomes were assessed pre-operatively and one year after OWHTO. Pre-operative characteristics (age, gender and body mass index) showed no significant difference between the two groups. The mean Japanese Orthopaedic Association score was significantly improved one year after operation regardless of the presence or absence of LHF (p = 0.0015, p < 0.001, respectively). However, six of seven type I cases had no LHF-related complications; both type II cases had delayed union; and of six type III cases, two had delayed union with correction loss and one had overcorrection. These results suggest that Takeuchi type II and III LHFs are structurally unstable compared with type I. Cite this article: Bone Joint J 2015;97-B:1226–31

Aims. To explore the of age of onset distribution for Perthes’ disease of the hip, with particular reference to gender, laterality and conformity to the lognormal distribution. Patients and Methods. A total of 1082 patients were identified from the Liverpool Perthes’ Disease Register between 1976 and 2010, of which 992 had the date of diagnosis recorded. In total, 682 patients came from the geographical area exclusively served by Alder Hey Hospital, of which 673 had a date of diagnosis. Age of onset curves were analysed, with respect to the predefined subgroups. Results. The age of onset demonstrated a positive skew with a median of 5.8 years (interquartile range 4.6 to 7.5). Disease onset was a mean five months earlier in girls (p = 0.01) and one year earlier in those who went on to develop bilateral disease (p < 0.001). There was no difference in the age of onset between geographical districts with differing incidence rates. The entire dataset (n = 992) conformed to a lognormal distribution graphically and with the chi-squared test of normality (p = 0.10), but not using the Shapiro-Wilk test (p = 0.01). The distribution for the predefined geographical subgroup (n = 673) conformed well to a lognormal distribution (chi-squared p = 0.16, Shapiro-Wilk p = 0.08). Given the observed lognormal distribution it was assumed that Perthes’ disease followed on incubation period consistent with a point-source disease exposure. The incubation period was further examined using Hirayama’s method, which suggested that the disease exposure may act in the prenatal period. Conclusion. The age of onset in Perthes’ disease conforms to a lognormal distribution, which allows comparisons with infectious disease epidemiology. Earlier onset in girls and those who develop bilateral disease may offer clues to understanding the aetiological determinants of the disease. The analysis suggests that an antenatal aetiological determinant may be responsible for disease. Take home message: Perthes’ disease age of onset conforms to a lognormal model, which is most typical of infectious diseases. The shape of the distribution suggests that an aetiological trigger in the pre-natal period may be an important determinant of disease. Cite this article: Bone Joint J 2016;98-B:710–14

Aims. The aims of this study were to evaluate the clinical and radiological outcomes of instrumented posterolateral fusion (PLF) performed in patients with rheumatoid arthritis (RA). . Methods. A total of 40 patients with RA and 134 patients without RA underwent instrumented PLF for spinal stenosis between January 2003 and December 2011. The two groups were matched for age, gender, bone mineral density, the history of smoking and diabetes, and number of fusion segments. . The clinical outcomes measures included the visual analogue scale (VAS) and the Korean Oswestry Disability Index (KODI), scored before surgery, one year and two years after surgery. Radiological outcomes were evaluated for problems of fixation, nonunion, and adjacent segment disease (ASD). The mean follow-up was 36.4 months in the RA group and 39.1 months in the non-RA group. Results. Both groups had significant improvement in symptoms one year after surgery, while the RA group showed some deterioration of outcome scores owing to complications during the second year after surgery. Complications occurred at a higher rate in the group with RA (19 patients, 47.5%) than in those without RA (23 patients, 17.1%) (p < 0.001). A total of 15 patients in the RA group (37.5%) required revision surgery, mainly for implant failure and post-operative infection. . Discussion. Multimodal approaches should be considered when performing instrumented PLF in patients with RA to reduce the rate of complications, such as problems of fixation, post-operative infection and nonunion. Take home message: Specific strategies should be undertaken in order to optimise outcomes in patients with rheumatoid arthritis. Cite this article: Bone Joint J 2016;98-B:102–8

We wished to estimate the incidence of surgical-site infection (SSI) after total hip replacement (THR) and hemiarthroplasty and its strength of association with major risk factors. The SSI surveillance service prospectively gathered clinical, operative and infection data on inpatients from 102 hospitals in England during a four-year period. The overall incidence of SSI was 2.23% for 16 291 THRs, 4.97% for 5769 hemiarthroplasty procedures, 3.68% for 2550 revision THRs and 7.6% for 198 revision hemiarthroplasties. Staphylococcus aureus was identified in 50% of SSIs; 59% of these isolates were methicillin-resistant (MRSA). In the single variable analysis of THRs, age, female gender, American Society of Anesthesiologists (ASA) score, body mass index, trauma, duration of operation and pre-operative stay were significantly associated with the risk of SSI (p < 0.05). For hemiarthroplasty, the ASA score and age were significant factors. In revision THRs male gender, ASA score, trauma, wound class, duration of operation and pre-operative stay were significant risk factors. The median time to detection of SSI was eight days for superficial incisional, 11 days for deep incisional and 11 days for joint/bone infections. For each procedure the mean length of stay doubled for patients with SSI. The multivariate analysis identified age group, trauma, duration of operation and ASA score as significant, independent risk factors for SSI. There was significant interhospital variation in the rates of SSI. MRSA was the most common pathogen to cause SSI in hip arthroplasty, especially in patients undergoing hemiarthroplasty, but coagulase-negative Staph. aureus may be more important in deep infections involving the joint

Aims. We assessed the difference in hospital based and early clinical outcomes between the direct anterior approach and the posterior approach in patients who undergo total hip arthroplasty (THA). Patients and Methods. The outcome was assessed in 448 (203 males, 245 females) consecutive patients undergoing unilateral primary THA after the implementation of an ‘Enhanced Recovery’ pathway. In all, 265 patients (mean age: 71 years (49 to 89); 117 males and 148 females) had surgery using the direct anterior approach (DAA) and 183 patients (mean age: 70 years (26 to 100); 86 males and 97 females) using a posterior approach. The groups were compared for age, gender, American Society of Anesthesiologists grade, body mass index, the side of the operation, pre-operative Oxford Hip Score (OHS) and attendance at ‘Joint school’. Mean follow-up was 18.1 months (one to 50). Results. There was no significant difference in mean length of stay (p = 0.07), pain scores on the day of surgery, the first, second and third post-operative days (p = 0.36, 0.23, 0.25 and 0.59, respectively), the day of mobilisation (p = 0.12), the mean OHS at six and 24 months (p = 0.08, and 0.29, respectively), the incidence of infection (p = 1.0), dislocation (p = 1.0), re-operation (p = 0.21) or 28 days’ re-admission (p = 0.06). Significantly more patients in the DAA group achieved a planned discharge target of three days post-operatively (68% vs 56%, p = 0.007). The rate of periprosthetic femoral fractures was significantly higher in the DAA group (p = 0.04). Conclusion. We conclude that there is no difference in clinical outcomes between the DAA and the posterior approach in patients undergoing THA when an ‘Enhanced Recovery’ pathway is used. However, a significantly higher rate of periprosthetic femoral fractures remains a concern with the DAA, even in experienced hands. Take home message: Our results show that the DAA for THA is not superior to posterior approach when ‘Enhanced Recovery’ pathway is used. Cite this article: Bone Joint J 2016;98-B:754–60

The aims of this study were to identify the early in-hospital mortality rate after hip fracture, identify factors associated with this mortality, and identify the cause of death in these patients. A retrospective cohort study was performed on 4426 patients admitted to our institution between the 1 January 2006 and 31 December 2013 with a hip fracture (1128 male (26%), mean age 82.0 years (60 to 105)). Admissions increased annually, but despite this 30-day mortality decreased from 12.1% to 6.5%; 77% of these were in-hospital deaths. Male gender (odds ratio (OR) 2.0, 95% confidence interval (CI) 1.3 to 3.0), increasing age (age ≥ 91; OR 4.1, 95% CI 1.4 to 12.2) and comorbidity (American Society of Anesthesiologists grades 3 to 5; OR 4.2, 95% CI 2.0 to 8.7) were independently and significantly associated with increased odds of in-hospital mortality. From 220 post-mortem reports, the most common causes of death were respiratory infections (35%), ischaemic heart disease (21%), and cardiac failure (13%). A sub-group of hip fracture patients at highest risk of early death can be identified with these risk factors, and the knowledge of the causes of death can be used to inform service improvements and the development of a more didactic care pathway, so that multidisciplinary intervention can be focused for this sub-group in order to improve their outcome. Cite this article: Bone Joint J 2015;97-B:246–51