Introduction. Improvements in function after THA can be evaluated using validated health outcome surveys but studies have shown that PROMs are unreliable in following the progress of individuals. Formal gait lab analysis is expensive, time consuming and fixed in terms of location. Inertial Measurement Units (IMUs) containing accelerometers and gyroscopes can determine aspects of gait kinematics in a portable package and can be used in the outpatient setting (Figure 1). In this study multiple metrics describing gait were evaluated pre- and post THA and comparisons made with the normal population. Methods. The gait of 55 patients with monarthrodial hip arthrosis was measured pre-operatively and at one year post-surgery. Patients with medical co-morbidity or other condition affecting their gait were excluded. Six IMUs aligned in the sagittal plane were attached at the level of the anterior superior iliac spines, mid-thigh and mid-shank. Data was analysed using proprietary software (Figure 2). Each patient underwent a conventional THA using a posterolateral approach. An identical test was performed one year after surgery. 92 healthy individuals with a normal observed gait were used as controls. Results. In the pre-operative test the range of movement in the sagittal plane of both the ipsilateral hip (mean range 20.4) and the contra-lateral non-diseased hip (35.3 degrees) was reduced compared to the control group (40.5 degrees), (P<0.001). The pre-operative range of motion of both knees was also reduced compared with normal (P<0.001). Pelvic movement on the ipsilateral side was increased. After one year the range of movement of the ipsilateral hip significantly improved (Mean range 28.9 deg SD 6.6) but did not attain normal values (P<0.001). Movement measured in the contralateral hip reduced further from its pre-operative value with a mean difference of −5.25 degrees (95% CI −8.06 to −2.43). Measurements of the symmetry of movement were increased. Knee movement on both sides increased but not to normal values (p<0.001). In contradistinction, there was bilateral increased coronal movement at the thigh and calf a year after surgery. Discussion and Conclusion. Gait after routine THA does not return to normal on the ipsilateral or contralateral side. Pathology in one hip causes bilateral gait abnormality that can be quantified by movement at the pelvis, hip, thigh and knee. The ability of a patient to walk normally after surgery will depend on many factors including details of the hip operation such as accurate recreation of the biomechanics of the joint and physical therapy regimens. Advances in technology now allow assessment of gait in large number of patients in the clinic setting and will better allow us to establish the important factors to improve patients gait and thereby potentially improve further satisfaction and PROMS scores. For any figures or tables, please contact authors directly (see Info & Metrics tab above).

Aims. To devise a simple clinical risk classification system for patients undergoing primary total knee arthroplasty (PTKR) to facilitate risk and cost estimation, and aid pre-operative planning. Methods. We retrospectively reviewed a series of consecutive PTKRs performed by the senior author. A classification system was devised to take account of principal risk factors in PTKR. Four groups were devised: 1) Non complex PTKR (CP0): no local or systemic complicating factors; 2) CPI: Locally complex: Severe or fixed deformity and/or bone loss, previous bony surgery or trauma, or ligamentous instability; 3) CPII Systemic complicating factors: Medical co-morbidity, steroid or immunosuppressant therapy, High BMI, (equivalent to ASA of III or more); 3) CPIII: Combination of local and systemic complicating factors (CPI+CPII). The patients were grouped accordingly and the following were compared: 1) length of stay, 2) post-operative complications, and 3) early post-discharge follow-up assessment. The complications were divided into local (wound problems, DVT, sepsis) and systemic (cardiopulmonary, metabolic, and systemic thromboembolic) complications. Results. The total number of patients was 119 (CP0=37,CPI=19,CPII=30,CPIII=33). Multiple regression analysis revealed: 1) no significant difference between complication rates in the CP0 and CPI groups, 2) 3-fold and 4-fold increase in the cumulative risk in the CPII and CPIII groups respectively (p<0.001), 3) significantly increased length of stay in the CPII and CPIII groups (p<0.001). Conclusion. The groups in this classification system correlate well with complication rates from surgery. As such this system has a role in stratifying patients for pre-operative planning and risk counselling. It is reproducible and can be used for larger patient groups via the National Joint Registry. Our findings also have implications for payment by results and fixed tariffs for PTKR, as the higher complication rates in the CPII and CPIII groups are likely to attract greater expense by hospitals in the course of these patients' treatment

Introduction. Following National patient safety alert on cement use in hip fracture surgery, we investigated the incidence and pattern of 72 hours peri-operative mortality after hip fracture surgery in a District General Hospital. Methods. We reviewed all patients who had hip fracture surgery between 2005-April, 2010. We recorded demographic variables, type of fracture, implant used, medical co-morbidity, seniority of operating surgeon and anaesthetist, peri-operative haemodynamic status, time and cause of death. Results. Over a 64 month period 15 cases were identified. Peri-operative death (PAD) was 1% (15/1402). 4/15 patients died intra-operatively. PAD was highest following Exeter Trauma Stem (ETS) implantation (5/85, 6%) and nil following Bipolar arthroplasty, Austin-Moore arthroplasty (AMA) or Cannulated screw fixation. PAD following total hip arthroplasty was 4% (1/25), Thompson's hemi-arthroplasty 2% (3/191), and Dynamic Hip Screw fixation 1% (6/695). Overall mortality after cemented implant was 2%. ETS implantation led to significantly increased peri-operative mortality compared to AMA (p=0.004). Operations were performed by both trainees (12) and Consultants (3). Both trainees (9) and Consultants (6) anaesthetised the patients. None of the patients belonged to ASA I or II (ASA III 6 and IV 9). All patients had significant cardio-vascular or pulmonary co-morbidity (Ca Lung 2, pulmonary fibrosis 1, end stage COAD 1, AF 6). Cemented implant insertion was followed by immediate haemodynamic collapse and death in 4/15, intra-operative haemodynamic instability in 1/15 and peri-operative instability in 5/15. Post-mortem was performed in 5/15: 2/5 were Pulmonary Embolism (PE), 2/5 bronchopneumonia and 1/5 Myocardial infarction (MI). 4/15 had suspected MI and 1/15 suspected PE. Conclusion. There was 1% risk of peri-operative death after hip fracture surgery. This risk was increased following cemented hemiarthroplasty and highest after ETS implantation. Risk was exacerbated in patients with pre-existing cardiovascular morbidity and independent of the seniority of the surgeon or the anaesthetist

INTRODUCTION. Revision knee arthroplasty is increasing and in 2010 constituted 6% of knee replacements done in the UK according to the National Joint Registry. 1. Infection was the 2nd most common cause accounting for 23% of the revision burden. 1. Two-stage revisions are considered the gold standard with success rates from 80–100%. 2. Single-stage revisions are becoming increasingly popular at certain centers with reported benefits of reduced “down-time” for the patient and a decreased financial burden. OBJECTIVES. The senior author (DSB) has been performing single-stage revisions for infections for over 10 years. We were interested in seeing the success rate for this method and possibly identify factors that would portend a poorer result. METHODS. We performed a retrospective review of all single-stage revisions performed at our hospital by the senior author (DSB) from January 2001 to December 2010. In total, 340 revision knee arthroplasties were performed. Of these, 13 (4%) single-stage revisions for infections were identified. The case records of these cases were reviewed and details of the revision as well as medical co-morbidities were assessed to see if any of these factors correlated to a poor outcome. In all, there were 8 women: 5 men with a mean age of 70.9 years (range 49–80 years). 1 case was lost to follow-up and 2 died from unrelated conditions. The mean duration of follow-up for the remaining 10 patients was 4.9 years (range from 1.5 to 7 years). RESULTS. All patients presented with knee pain along with swelling (30%), stiffness (30%), instability (8%). 2 patients had a chronic discharging sinus. Most patients (92%) had at least 1 medical co-morbidity (e.g. steroid use, diabetes, malignancy, Crohn's disease). The mean time from index surgery to revision was 3.5 years (range 1 to 9 years). The causative microbe identified prior to surgery was MRSA (15%), MSSA (30%), coagulase-negative Staphylococcus (30%), Streptococcus Gp D (8%) and polymicrobial growth (MSSA with Pseudomonas) (8%). In 3 cases, no microbe was identified. Intraoperative findings were extensive scarring of the soft tissue in all cases with single component loosening in 30% and both component loosening in 15%. Post-operative complications included 1 case of cellulitis, 1 case of chronic regional pain syndrome and 1 case of hemarthrosis. Most cases had excellent ROM at their last follow-up. The final surgical outcome of the 10 patients at final follow-up were successful infection eradication in 9 (90%) and 1 failure (10%) requiring repeat 2-stage revision. This failure was the only case with a positive polymicrobial culture prior to his surgery growing MSSA with Pseudomonas. Cases in which we failed to identify the causative organism prior to surgery did not appear to impact on the success rate. CONCLUSION. We submit that a high success rate can be achieved using single-stage revision along with the potential for improved patient functional outcome due to a lack of “down-time” during the interval of the 2-stage revisions. We, however, cannot advocate this to be undertaken by all surgeons as we still accept that the gold standard remains the 2-stage revision