Introduction. The management of peri-prosthetic distal femur fractures following TKR (Total Knee Replacement) in the elderly remains a challenge with little or no consensus on the best available treatment. Various methods have been described in the management of these complex fractures. Our study compares the outcome and cost of distal femoral arthroplasty to that of Fixation (Plating/Retrograde Nailing). Methods. We retrospectively reviewed our database for patients admitted with peri-prosthetic distal femoral fractures between 2005–2013 (n=61). The patients were stratified into 2 groups based on method of management. The Distal Femoral Arthroplasty group (Group A) had 21 patients, with a mean age of 78 years (68–90. The Fixation group (Group B) had 40 patients, with a mean age of 74 years, 23 of those had plating of the fracture, while 17 had a retrograde nail inserted. Pain scores, Length of stay, intra-operative blood loss, and weight bearing status, were compared. Functional outcomes were also assessed using Oxford knee scores, KSS scores, VAS pain assessment and range of motion from last follow up appointment. Minimum follow-up was 2 years. Cost analysis was done for both groups, which included implant costs, consumable costs (man power included), theatre utilisation time and length of hospital stay. The calculation was done based on the PbR (payment by results) system and “best practise tariffs 2010–11” utilised by the NHS (National Health Service) in England. Results. In group A, the average surgical time was 116 minutes with mean blood loss of 400 ml. In group B, the mean surgical time was 123 minutes with average blood loss of 800 ml. The mean length of hospital stay in group A was 9 days whereas in group B was 32 days. All patients were fully weight bearing by day 1.5(range 1–3 days) in group A, compared to a mean of 11 weeks in group B. Mean Oxford score was 28 and KSS score was 70 in group A compared to 27 and 68 in group B. The pain score on VAS was 2 for group A and 1.5 for group B. The mean ROM of the knee was 95° in group A and 85° in group B. We had 4 complications in group A. There were 2 deaths due to medical co-morbidities, 1 superficial infection, and 1 DVT. In the fixation group, there were 6 deaths due to medical co-morbidities, 1 failure of fixation, 6 mal-unions, 1 non-union and 2 infections. Overall, the distal femoral arthroplasty procedure costs approximately £10000, and the fixation group costs were on average of £9800. Discussion & Conclusion. Distal femoral arthroplasty allowed early mobilisation, thus avoiding prolonged hospital stay and reducing the risk of inpatient related morbidity. Complication rates were lower than the fixation group and the overall costs were comparable to that of fixation. Distal femoral arthroplasty appears to be a promising alternative treatment to internal fixation in elderly patients with distal femoral peri-prosthetic fractures. With appropriate patient selection, the prosthesis is likely to survive for the duration of patient's lifetime

Purpose:. Biomechanical knowledge of the medial collateral ligament (MCL) is important for MCL release during knee arthroplasty. The purpose of this study was to define the influences of the deep medial collateral ligament (dMCL) and the posterior oblique ligament (POL) on valgus and rotatory stability in knee arthroplasty. Methods:. Six cadaveric knees were divided into 2 groups with unique sequential sectioning sequences of the dMCL and the POL. Group A (n = 2) first received femoral arthroplasty only, and thereafter sequentially received medial half tibial resection with spacer, ACL cut, dMCL cut, POL cut, and finally tibial arthroplasty. Group B (n = 4) first received femoral arthroplasty only, and thereafter sequentially received medial half tibial resection with spacer, ACL cut, tibial arthroplasty, dMCL cut, and finally, POL cut. A CT-free navigation system monitored motion after application of valgus loads (10 N-m) and internal and external rotation torques (5 N-m) at 0°, 20°, 30°, 60°, and 90°of knee flexion. Results:. There were no significant differences in medial gaps under valgus loads after cutting dMCL, but significant differences were seen in medial gaps after cutting POL. Internal rotation angles increased after cutting POL under internal rotation torques at over 20°of knee flexion. External rotation angles under external rotation torques increased after cutting dMCL at 90°. In addition, external rotation angles further increased after cutting POL. Accordingly, while increases of medial gap size and rotatory instability were not clearly recognized with the sectioning of the dMCL, significant increases of valgus and rotatory instability were seen on sectioning of the POL

Introduction. Many factors can influence post-operative kinematics after total knee arthroplasty (TKA). These factors include intraoperative surgical conditions such as ligament release or quantity of bone resection as well as differences in implant design. Release of the medial collateral ligament (MCL) is commonly performed to allow correction of varus knee. Precise biomechanical knowledge of the individual components of the MCL is critical for proper MCL release during TKA. The purpose of this study was to define the influences of the deep medial collateral ligament (dMCL) and the posterior oblique ligament (POL) on valgus and rotatory stability in TKA. Materials and Methods. This study used six fresh-frozen cadaveric knees with intact cruciate ligaments. All TKA procedures were performed by the same surgeon using CR-TKA with a CT-free navigation system. Each knee was tested at 0°, 20°, 30°, 60°, and 90° of flexion. One sequential sectioning sequence was performed on each knee, beginning with an intact knee (S0), and thereafter femoral arthroplasty only (S1), tibial arthroplasty (S2), release of the dMCL (S3), and finally, release of the POL (S4). The same examiner applied all external load of 10 N-m valgus and a 5 N-m internal and external rotation torque at each flexion angle for the each cutting state. All data were analyzed statistically using one-way ANOVA and we investigated the correlation between the medial gap and the rotation angle. A significant difference was determined to be present for P < .05. Results. There were no correlation between the medial gap and the rotation angle in S0. A moderate correlation was found in S1 at 0° and 20°, and a considerable correlation was found in S2 at 90°. There was a correlation at all angles in S4, and especially strong at 20°, 60°, 90°. Conclusion. From this study, there were no correlation between medial knee instability and total rotation angles after performing TKA only by releasing dMCL, but by adding POL release, there were correlation in all angles. Therefore, medial knee instability caused by excessive release of the main medial knee structures may promote rotational instability

Introduction. Many factors can influence post-operative kinematics after total knee arthroplasty (TKA). These factors include intraoperative surgical conditions such as ligament release or quantity of bone resection as well as differences in implant design. Release of the medial collateral ligament (MCL) is commonly performed to allow correction of varus knee. Precise biomechanical knowledge of the individual components of the MCL is critical for proper MCL release during TKA. The purpose of this study was to define the influences of the deep medial collateral ligament (dMCL) and the posterior oblique ligament (POL) on kinematics in TKA. Materials and Methods. This study used six fresh-frozen cadaveric knees with intact cruciate ligaments. All TKA procedures were performed by the same surgeon using CR-TKA with a CT-free navigation system. Each knee was tested at 0°, 20°, 30°, 60°, and 90° of flexion. One sequential sectioning sequence was performed on each knee, beginning with femoral arthroplasty only (S1), and thereafter sequentially; medial half tibial resection with spacer (S2), ACL cut (S3), tibial arthroplasty (S4), release of the dMCL (S5), and finally, release of the POL (S6). The same examiner applied all external loads of 10 N-m valgus and 5 N-m internal and external rotation torques at each flexion angle and for each cut state. The AP locations of medial and lateral condyles were determined as the lowest point on each femoral condyle. All data were analyzed statistically using paired t-test. A significant difference was determined to be present for P < .05. Results. All knees showed that posterior femoral translation of the lateral condyle from 0° to 90° was greater than posterior femoral translation of the medial condyle at any step or any tested angle. Posterior femoral translation of the medial femoral condyle under valgus load significantly increased after S4 compared with that at S1 at 20°, 30° and 90°, and after S5 compared with that at S1 at 20° and 30°. Thereafter, significant increase in posterior translation of the medial condyle was seen, at 30° after S6 compared with S1. Posterior femoral translation of the medial femoral condyle under external rotation torque significantly increased after S4 at 90°, and S6 at 0° compared with that at S1. Posterior femoral translation of the medial femoral condyle under internal rotation torque significantly increased after S2 at 0°, after S4 at 60° and 90°, after S5 at 0°, and after S6 at 60° compared with S1. Conclusion. From this study we concluded that retaining of the medial knee structures preserves the valgus and rotatory stability of the knee after TKA. Accordingly, to devise a surgical approach of retaining the dMCL and POL has a possibility to improve outcomes after primary TKA

Introduction. Many factors can influence post-operative kinematics after total knee arthroplasty (TKA). These factors include intraoperative surgical conditions such as ligament release or quantity of bone resection as well as differences in implant design. Release of the medial collateral ligament (MCL) is commonly performed to allow correction of varus knee. Precise biomechanical knowledge of the individual components of the MCL is critical for proper MCL release during TKA. The purpose of this study was to define the influences of the deep medial collateral ligament (dMCL) and the posterior oblique ligament (POL) on valgus and rotatory stability in TKA. Materials and Methods. This study used six fresh-frozen cadaveric knees with intact cruciate ligaments. All TKA procedures were performed by the same surgeon using CR-TKA with a CT-free navigation system. Each knee was tested at 0°, 20°, 30°, 60°, and 90° of flexion. One sequential sectioning sequence was performed on each knee, beginning with femoral arthroplasty only (S1), and thereafter sequentially, medial half tibial resection with spacer (S2), ACL cut (S3), tibial arthroplasty (S4), release of the dMCL (S5), and finally, release of the POL (S6). The same examiner applied all external loads of 10 N-m valgus and 5 N-m internal and external rotation torques at each flexion angle and for each cut state. All data were analyzed statistically using two-way ANOVA and paired t-test. A significant difference was determined to be present for P < .05. Results. There were no significant differences in medial gaps at any sequential step or any tested angle of flexion under valgus loads even after release of the dMCL and the POL compared with those at S1. Internal rotation angles significantly increased after medial half tibial resection with spacer, compared with those after S1, at 0°, 20°, and 30°. Moreover, release of the POL under internal rotation torque resulted in significantly increased internal rotation, compared with that at S1, at 90° of knee flexion. External rotation angles under external rotation torque significantly increased after the ACL cut compared with those at S1 at 0°, and after tibial arthroplasty, significant increase in external rotation angles compared with those at S1 was observed at 60°. Thereafter, significant increase in external rotation angles was seen, at 0°, 30° and 90° after release of the dMCL compared with S1, and significant increase after release of the POL at 30°, 60° and 90° compared to S1. 20°. Rotational angles had correlation with the size of medial gap at 0°, 20° and 90°. Conclusion. From this study we concluded that retaining of the medial knee structures preserves the valgus and rotatory stability of the knee. Accordingly, to devise a surgical approach of retaining the dMCL and POL has a possibility to improve the outcome after primary TKA

Introduction. Modular femoral necks have shown promising clinical results in total hip arthroplasty (THA) to optimize offset, rotation, and leg length. Given the wide variety of proximal femoral morphology, fine-tuning these kinematic parameters can help decrease femoroacetabular impingement, decrease wear rates and help prevent dislocations. Yet, additional implant junctions introduce additional mechanisms of failure. We present two patients who developed an abnormal soft tissue reaction consistent with a metal hypersensitivity reaction at a modular femoral neck/stem junction requiring revision arthroplasty. Methods. Two patients underwent THA for primary osteoarthritis with the same series of components: 50 mm shell, a 36 mm highly-crosslinked polyethylene liner, uncemented titanium alloy modular stem with a 130 degree Cobalt Chromium (CoCr) modular femoral neck, and 36 mm CoCr head with a +5-mm offset. Patient 1 was a 63 year-old female who had an uneventful post-operative course but presented seven months later with progressive pain in the left hip. Patient 2 was an 80 year-old female who did well post-operatively, but presented with limp and persistent pain at 10 months post-op. An initial evaluation of a painful THA to rule out aseptic loosening, infection, mal-positioning, loosening and osteolysis included radiographs, lab work (CBC, ESR, CRP, Cobalt & Chromium levels) and Metal Artifact Reduction Sequence (MARS) MRI. Results. Elevated ion levels (Table 1) and Metal Artifact Reduction Sequence (MARS) MRI were consistent with an abnormal soft tissue reaction. A histological analysis of operative specimens displayed extensive necrosis and lymphocytosis, consistent with the diagnosis of metal hypersensitivity reactions (MHSR). Both patients underwent debridement and revision femoral arthroplasty with non-modular counterparts of the original femoral implant and have been asymptomatic post-operatively at greater than 1 year follow-up. Discussion. MHSR reactions are primarily described in the setting of metal on metal articulations of the head and acetabulum in THA and hip resurfacing. These reactions have not been reported at the modular neck/stem junction. Although modular necks show promise in THA, the advantages of increased component modularity must be carefully weighed against the risks of mechanical wear and subsequent MHSR and/or component failure

Introduction

In response to the COVID-19 pandemic, there was a rapidly implemented restructuring of UK healthcare services. The The Royal National Orthopaedic Hospital, Stanmore, became a central hub for the provision of trauma services for North Central/East London (NCEL) while providing a musculoskeletal tumour service for the south of England, the Midlands, and Wales and an urgent spinal service for London. This study reviews our paediatric practice over this period in order to share our experience and lessons learned. Our hospital admission pathways are described and the safety of surgical and interventional radiological procedures performed under general anaesthesia (GA) with regards to COVID-19 in a paediatric population are evaluated.