Aims

With up to 40% of patients having patellofemoral joint osteoarthritis (PFJ OA), the two arthroplasty options are to replace solely the patellofemoral joint via patellofemoral arthroplasty (PFA), or the entire knee via total knee arthroplasty (TKA). The aim of this study was to assess postoperative success of second-generation PFAs compared to TKAs for patients treated for PFJ OA using patient-reported outcome measures (PROMs) and domains deemed important by patients following a patient and public involvement meeting.

Abstract

Studies have shown that 10–30% patients do not achieve optimal function outcomes after total hip replacement (THR). High quality randomised controlled trials (RCTs) evaluating the clinical and cost-effectiveness of techniques to improve functional outcomes after THR are lacking. We performed this study to evaluate the feasibility of a RCT comparing patient-reported functional outcomes after hybrid or fully cemented THR (ISRCTN11097021).

Patients were recruited from two centres and randomised to receive either a fully cemented or hybrid THR. Data collection included Patient Reported Outcome Measures (PROMs), non-serious adverse events of special interest (AESI), serious adverse device effects (SADE) and NHS resource use. Qualitative interviews were undertaken to understand a) patient experiences of study processes and their reasons for taking part or not, and b) to understand surgeons’ perceptions of the study, factors affecting willingness to participate, and barriers to implementation of the future RCT findings.

The target of 40 patients were successfully recruited for the feasibility RCT; the ratio of successful recruitment to eligible patients was 0.61 across both sites. Treatment crossovers occurred in four patients, all related to bone quality. Four patients were withdrawn due to not undergoing surgery within the study window because of the pandemic. Follow-up was 100% and PROMs were completed by all patients at all time points. The feasibility of conducting a within-trial cost-utility analysis was demonstrated. Interviews were conducted with 27 patients and 16 surgeons. Patients and surgeons generally found the study procedures acceptable and workable. Some declined participation because they did not want treatment allocated at random, or because blinding was off-putting. Surgeons’ perceptions of equipoise varied, and implementation of findings from the future RCT would need to recognise the ‘craft’ nature of surgery and the issue of training.

We conclude that a full RCT with economic analysis will be both feasible and practicable, although mechanisms to safely implement potential changes to practice because of RCT findings may need consideration by the wider arthroplasty community.

Abstract

Abstract

The Coronavirus pandemic mandated an immediate and dramatic change in the delivery of acute trauma services to minimise face-to-face contact. In our hospital, patients presenting to the Emergency Department with a knee injury and no fracture seen on Xrays were referred to a “Virtual Fracture Clinic” (VFC) where Xrays and clinical notes were reviewed by the duty Trauma and Orthopaedic Consultant the following working day. We present the outcomes of 101 consecutive patients managed through this process and deemed to have a “Soft Tissue Knee Injury” with a minimum follow-up of six months.

All Xrays were reviewed by a sub-specialist knee surgeon blinded to notes or clinical outcomes. Electronic clinical records were reviewed to determine further clinical appointments, surgical treatment and pending interventions.

Of 101 patients, the knee surgeon diagnosed 1 Fracture, 4 Lipo-haemarthroses, 41 significant effusions and 55 patients with normal Xrays. Correlation to urgent surgery was 100% for fracture (1/1), 25% for Lipo-haemarthrosis (1/4), 7.3% for significant effusion (3/41) and 9.1% for normal Xrays (5/55). A further 9.8% (4/41) of the “effusion” group and 7.3% (4/55) of the “normal” group were subsequently listed for non-urgent surgery.

Overall 17% (7/41) of “effusion” patients and 16% (9/55) of “normal” patients required surgery. Management plans from VFC varied within groups.

Acute “soft-tissue” injuries of the knee in adults cannot be reliably managed via VFC based on X-ray findings. A staged review by an appropriately trained health professional could reduce demand on acute knee surgical clinics and may enhance patient outcomes.

The ODEP (Orthopaedic Data Evaluation Panel) rating system should offer a surgeon and patient extra information when making a choice on which implant to use. However, in the current economic environment, ratings may also influence implant choice by contracting bodies. Our aim was to determine the performance of commonly used Acetabular and femoral components in our unit and compare these to their published ODEP ratings (or absence of rating).

We analysed all of the following primary THR components (12,792) for revision for any reason, using same date ranges as ODEP where more than 100 implantations had occurred. Hip components: Trinity (3A in 2013), Trilogy (10A* in 2016), Atlas (10A in 2013), Trilogy TMT (10A 2010) Durom (not rated), BHR (10A, 2010), ACCIS (not rated); Femoral components: Taperfit (10A in 2013), Taperloc (10A* in 2016), Metafix (3A in 2013), CPT (10A in 2012), Ecofit (not Rated), ESOP (not rated), Minihip (3A 2013), Durom (not rated), BHR (10A 2010), ACCIS (not rated).

Analysis of Kaplan Meier survival curves was undertaken for all components. The rated components and non-rated components were compared using HR and logrank tests for all time groups when ratings were introduced. No statistical difference was observed in any group except for the Trinity cup which had a 98.2% (1344 cups) survival at 6 years.

Component survival in our unit was better than ODEP suggested failure for A category of not more than 1% per year, for all components.

Whilst we applaud the intention to improve data available for prostheses, the present ODEP system does not distinguish between performances of different implants in our unit. We therefore recommend care when relying upon ODEP ratings to make clinical or contracting decisions.

Introduction

There is little information available to surgeons regarding how the lateral soft-tissue structures prevent instability in knees implanted with total knee arthroplasty (TKA). The aim of this study was to quantify the lateral soft-tissue contributions to stability following cruciate retaining (CR) TKA.

Aim

The purpose of this study was to quantify the number of children treated with ESIN (elastic stable intra-medullary nails) at our institution and to determine what proportion of these nails have been removed and the time and difficulty taken to do so.

A study to assess the clinical importance of asymmetric thigh creases as the sole clinical sign in the diagnosis of developmental dysplasia of the hip.

Aim

To evaluate the influence of arthrodiatasis in the natural history of the stages of the disease radiologically and also the timing of arthrodiatasis.

Introduction

The advent of double bundle ACL (Anterior Cruciate Ligament) reconstruction had been hailed as potentially allowing for more anatomically and physiologically functioning graft, however until recently there had been little evidence of enhanced functional outcomes.

The aim of this study is to explore whether the dimensions of hamstring two strand single bundle grafts, are predictive of the combined four strand single bundle graft that results from combining the single bundle grafts, as well as the impact of double bundle grafts upon the available healing and attachment area within the bony tunnels.

Subtalar dislocation of the hindfoot is a rare injury and can be associated with poor functional outcomes. We report a case of an irreducible subtalar dislocation in an elite athlete, who returned to elite sport.

A 28 year old competitor in the world mountain bike championships was injured in a high speed fall from his mountain bike during a competitive downhill run in July 2007. He had an obvious deformity at the scene and a fracture dislocation of the ankle was suspected. The injury was closed and neuro-vascular status was intact. Radiographs revealed the ankle mortise was intact with the talus anatomical, but a subtalar dislocation was present which proved irreducible in the emergency department.

The patient was taken to the operating theatre and the dislocation was reduced through a short antero-medial arthrotomy using a blunt lever and traction. Post- reduction, the joint was stable and was supported in a below knee cast. He was kept partial weight bearing for 6 weeks and then had an intensive physiotherapy rehabilitation regime. Serial radiology showed no evidence of avascular necrosis or other skeletal abnormalities.

Our patient has since returned to elite Mountain Biking and won the British National Championships in 2008 and the World Championships in Canberra in 2009.

The aim of this study was to assess the increase in the anterior diameter of the knee and the impact of this increase on the range of motion and function of the knee.

Twenty-eight patients (34 knees) who underwent Patello-femoral replacement with FPV (Wright Medical) prosthesis between 2005 and 2009 who were identified retrospectively and analyzed using chart and radiological review. Oxford and AKSS knee-scores were gathered prospectively pre-operative and at follow-up.

Trochlear height was measured using lateral radiograph. Trochlear height was compared pre and postoperatively. Patellar height was also measured in preoperative and postoperative skyline view and was compared. The range of movement at six weeks and the Oxford and American knee society knee scores at six months postoperatively were noted. Association between increased anterior height and improved range of motion was studied.

All but three-knees regained full knee extension. Postoperative mean range of flexion of the knee joint was 116 degrees. The mean Oxford knee and the mean American Knee Society Knee Scores significantly improved post-operatively

The trochlear height was increased by 4mms. Patellar height was also increased by 3 mms resulting in average total increase of 7 mms in the anterior-posterior diameter of the knee. We found no relationship between range of motion of the knee and the increase in the anterior-posterior diameter. We found a negative correlation between increase in the antero-posterior and preoperative trochlear and patellar height.

We conclude that FPV Patello-femoral replacement results in correct anatomical reconstruction of the trochlear height rather than ‘overstuffing’ of the patellofemoral joint which can lead to stiffness and failure of resolution of pain post-operatively. This should in turn result in durable improvements in pain and function.

Patellofemoral unicompartmental joint replacement is a controversial subject with a relatively small evidence base. Of the 50,000 total knee arthroplasties performed each year in the UK, approximately 10% are performed for predominantly patellofemoral arthritis. There are several patellofemoral unicompartmental prostheses on the market with the National Joint Registry recording 745 such prostheses used in 2007. Most evidence in favour of this procedure comes from experience with the Avon prosthesis (Stryker) predominantly from designer-surgeons.

The FPV patellofemoral joint replacement (Wright Medical) has been in use in Europe for several years. The instruments have recently been redesigned and the device marketed in the UK. In 2007 the FPV had 5.9% market share (n=44). We present our early experience with the FPV patellofemoral joint replacement, which to our knowledge, is the first clinical outcome series for this prosthesis.

33 consecutive FPV joint replacements in 29 patients were performed between April 2007 and September 2009 for unicompartmental patellofemoral OA. All cases were performed or directly supervised by the senior author. Results are presented with a minimum follow-up of six months.

Oxford and American Knee Society scores (AKSS) were obtained on all patients preoperatively and at subsequent outpatient visits. Mean preoperative AKSS knee score was 49.7 points and postoperative scores at 6 months and 1 year were 82.5 and 86.4 respectively. Mean Oxford score preoperatively was 30.4 (37%) and at 6 months and 1 year were 21.3 (56%) and 11.2 (77%) respectively.

There were no complications related to the implant. One knee required a secondary open lateral release due to inadequate balancing at the index procedure.

Further medium to long-term follow up data are required, but our initial experience with this device is encouraging.

Patellofemoral unicompartmental joint replacement is a controversial subject with a relatively small evidence base. Of the 50,000 total knee arthroplasties performed each year in the UK, approximately 10% are performed for predominantly patellofemoral arthritis. There are several patellofemoral unicompartmental prostheses on the market with the National Joint Registry recording 745 such prostheses used in 2007. Most evidence in favour of this procedure comes from experience with the Avon prosthesis (Stryker) predominantly from designer-surgeons.

The FPV patellofemoral joint replacement (Wright Medical) has been in use in Europe for several years. The instruments have recently been redesigned and the device marketed in the UK. In 2007 the FPV had 5.9% market share (n=44). We present our early experience with the FPV patellofemoral joint replacement, which to our knowledge, is the first clinical outcome series for this prosthesis.

33 consecutive FPV joint replacements in 29 patients were performed between April 2007 and September 2009 for unicompartmental patellofemoral OA. All cases were performed or directly supervised by the senior author. Results are presented with a minimum follow-up of six months.

Oxford and American Knee Society scores (AKSS) were obtained on all patients preoperatively and at subsequent outpatient visits. Mean preoperative AKSS knee score was 49.7 points and postoperative scores at 6 months and 1 year were 82.5 and 86.4 respectively. Mean Oxford score preoperatively was 30.4 (37%) and at 6 months and 1 year were 21.3 (56%) and 11.2 (77%) respectively.

There were no complications related to the implant. One knee required a secondary open lateral release due to inadequate balancing at the index procedure.

Further medium to long-term follow up data are required, but our initial experience with this device is encouraging.

We report the clinical results of seven consecutive allograft knee ligament reconstructions using Achilles tendon prepared using a chemical treatment process. Results have been disappointing with six clinical failures at short durations of follow-up. All allografts are not the same and the method of tissue preparation may have important consequences for clinical outcomes.

Debate regarding the use of allograft or autograft tissue for knee ligament reconstruction continues. A variety of allograft tissues are available from commercial and NHS sources: fresh frozen, freeze dried, irradiated or chemically prepared. There are gaps in the literature with respect to clinical outcomes for these various methods of graft preparation. A recent systematic review indicated similar short-term clinical outcomes for fresh frozen allografts and autografts.

The senior author began using allograft Achilles tendon for revision ACL reconstruction or primary multiple ligament reconstruction in 2007. Tissues were obtained from a commercial supplier. These tissues had been harvested in Eastern Europe, transported to the USA and sterilised using a patented “Biocleanse” chemical treatment process. This involves sequential ultrasonic baths of detergent, peroxide and alcohol for fixed periods of time along with pressure and vacuum cycles.

Between April 2007 and April 2009, 7 allograft ligament reconstructions were performed in 5 knees. These comprised 5 ACL and 2 LCL reconstructions. At follow up of between 4 months and 2 years, clinical failure of 6 grafts has been observed. We are aware of one previous series of results for ACL reconstructions using chemically sterilised and irradiated allograft tissues. A 45% graft failure rate was reported. We have not been able to identify any clinical outcome studies for grafts prepared using the “Biocleanse” process.

Our results have prompted us to change to UK sourced, donor screened allografts, which are fresh frozen after decontamination with 70% ethanol.

Aim: To review our experience with epiphysiodesis using three different methods to correct LLD and to establish the efficacy of these procedures.

Method: A retrospective review of 42 patients from 1999 to 2008 with at least one year follow-up recorded type and location of the epiphysiodesis, average operating time and hospital stay, complications, method of prediction, timing and the final LLD. CT scanograms and mechanical axis view with grids were used to assess LLD.

Results: Epiphysiodesis was as per Canale for 26, by Metaizeau screw in 14 and by staples in 2. Average operation time was 42 minutes for Canale type, 45 minutes for the screws and 56 minutes for the staple cases. The pre operative LLD of 3.7 cms In the Canale group, improved to 1.2 cms over an average follow-up of 2.1 yrs. There were 4 minor and 2 major complications with a 92% success rate. For the screw group, the mean change was 1.8 cms over 2.2 yrs with 2 minor and 2 major complications giving a success rate of 85%. With staples the success rate was 100% and the mean change was 1.8 cms at an average of 2.3 yrs. In 14 cases where bone age reports were available, the multiplier method seemed better at predicting estimated LLD at skeletal maturity and timing of epiphysiodesis than the Moseley chart.

Conclusions: Percutaneous epiphysiodesis by any method is reliable, minimally invasive and with acceptable complication rate when compared to a corrective osteotomy or open Phemister-type epiphysiodesis. Our experience suggests that the Canale method has the least complications and best success rate. Paleys multiplier method was better at predicting LLD and timing of epiphysiodesis than the Moseley Chart.

The study aims to determine the effects of obesity on the patients’ symptoms and their knee function before knee arthroplasty, as well as their states of anxiety and depression.

Ethical approval was obtained before the start of the study. Weights and heights of all patients were measured and BMI calculated on admission. Anxiety and depression states were recorded using the Hospital Anxiety and Depression Scale (HADS). The severity of pain and loss of function of the knees undergoing arthroplasty was measured using the Oxford Knee Score and the American Knee Society Score. All scores were measured per-op and again at 6 weeks post-op.

To date, 28 patients were included. The mean body mass index was 28.9. Only six patients had a BMI of < 25. Patients with normal BMI (< 25) had mean anxiety and depression scores of 6.8 and 5.67 respectively. Overweight patients (BMI > 25) had scores of 5.59 and 4.9 respectively. Patients with BMI > 30 had scores of 6.71 (p= 0.22) and 7.0 (p= 0.04) respectively.

Patients with BMI > 30 had an improvement in anxiety scores of 1.33 points compared with 0.55 for patients with BMI < 30 (p= 0.3). Depression scores improved by 4 points in the BMI > 30 group compared with 0.67 in the BMI < 30 group (p= 0.03).

Improvements in the knee scores were comparable in both groups.

Obese patients with BMI of > 30 have higher rates of anxiety and depression pre-operatively. At 6 weeks follow up, there is an improvement in both measures of psychological distress but this is more pronounced for depressive symptoms.

Aim:This study was carried out to assess various factors responsible for the development of avascular necrosis and the effect of treatment on clinical outcome.

Methods: We studied the clinical notes and radiographs of patients presenting with SCFE during the period between 1994 and 2003.

Results: Seventy three patients (n=73) with ninety two (n=92) hips were included in the study. There were 16 acute, 43 acute-on-chronic, 29 chronic and 4 preslips. Seventy Seven (n = 77) slips were classified as stable and 15 as unstable slips. Fifty three slips (57.6%) were mild, 34 (37%) were moderate and five (5.4%) were severe slips. Despite no deliberate attempts to reduce the slip at the time of surgery eighteen hips (n=18) showed a median decrease in slip angle of 8 degrees (range 2–36) in acute and acute-on-chronic slips. The mean preoperative slip angle was 32 degrees (range 9–76) compared to postoperative slip angle of 29.9 degrees (range 10–75) (p=0.004). Four patients developed avascular necrosis (AVN). Intraoperative reduction of the slip was significantly related to development of AVN (p< 0.001). According to the criteria of Heyman and Herndon eight patients had functional deficit at the time of final follow up and clinical outcome was fair, poor or failure. All of these patients had a reduction in the angle of slip at the postoperative radiographs compared to their preoperative radiographs.

Conclusion: Reduction of slipped capital femoral epiphysis is responsible for poor outcome and also related to the development of avascular necrosis. We recommend single in situ pinning for these cases regardless of severity of slip.

Cobalt chrome-on-cobalt chrome bearing surfaces have been re-introduced despite some concerns regarding potential risks posed by soluble metallic by-products. We have investigated whether there are metal-selective differences between the levels of genetic damage caused to a human cell line when cultured with synovial fluids retrieved from various designs of orthopaedic joint replacement prostheses at the time of revision arthroplasty.

Synovial fluids were retrieved from revision hip and knee arthroplasty patients with bearings made from cobalt chrome-on-cobalt chrome, cobalt chrome-on-polyethylene and stainless steel-on-polyethylene. Control synovial fluids were retrieved from primary arthroplasty cases with osteoarthritis. Synovial fluid was cultured with human primary fibroblasts for 48 hours in a cell culture system under standardised conditions. The “Comet” assay was used with an image analysis system to measure levels of DNA damage caused by the various synovial fluid samples.

Synovial fluids from cobalt chrome-on-cobalt chrome and cobalt chrome-on-polyethylene joint replacements both caused substantial levels of genetic damage as detected by the Comet assay. Synovial fluids retrieved from stainless steel-on-polyethylene joints caused low levels of damage. The difference between these groups was highly statistically significant (p< 0.001). Control synovial fluids from osteoarthritic joints caused minimal changes. Atomic absorption spectroscopy demonstrated that the metal-on-metal synovial fluids contained the highest levels of cobalt and chromium. Different alloys used in orthopaedic implants are associated with different levels of DNA damage to cultured human cells in vitro. We are able to demonstrate that this damage is attributable at least in part to the metal content of the synovial fluid samples. We have no evidence for any long-term health risk to patients with such implants.