Knee replacement surgery can greatly improve pain, disability, quality of life and ability to work. Socioeconomic deprivation is associated with multiple poor health outcomes, partly due to reduced access to services, including surgery. We investigated whether deprivation was associated with characteristics at presentation, and outcomes following knee arthroplasty. We linked data from 2358 knee arthroplasty cases with the Index of Multiple Deprivation, and mortality data after mean 7.6 years follow up. A locally developed scoring system was used prospectively to categorise case complexity.Abstract
Introduction
Methodology
MRI scanning is the establish method of defining intra- and extra-articular diagnoses of patients with non-arthritic knee problems. Discrepancies in reporting have been noted in previous historic studies and anecdotally. The aim of this study was to analyse the reporting of intra-articular pathology and discrepancies in knee MRI reports by two clinician groups, consultant radiologists and consultant knee surgeons in a district hospital setting. A retrospective case-controlled cohort study was conducted using data collected from an outpatient physiotherapy-led knee clinic. Seventy-four patients in the cohort were referred for an MRI scan of their knee(s) following a clinical examination and history. MRI reports from both the consultant knee surgeon and the radiologist were entered into a database with other clinical details. Reports were analysed to determine number of diagnoses and degree of agreement. Each report was deemed to either completely agree, completely disagree or partially agree.Abstract
Introduction
Methods
The most frequent mode of aseptic failure of primary total knee replacements is tibial baseplate loosening. This is influenced by stresses across the implant-bone interface which can be increased in obese patients leading to potentially higher rates of early failure. The evidence is mixed as to the true effect of elevated BMI (body mass index) on revision rates. We present the experience of early tibial failures in our department and how our implant choices have evolved. We retrospectively reviewed our unit's arthroplasty database and identified all patients who had sustained mechanical tibial failure. Data were collected on patient demographics, operative details of primary and revision operations, components used, alignment pre and post operatively and indication. Complications and further surgery performed were recorded.Abstract
INTRODUCTION
METHODOLOGY
Orthopaedic practice is increasingly guided by conclusions drawn from analysis of Joint Registry Data. Analysis of the England and Wales National Joint Registry (NJR) led Sibanda et al to conclude that UKR should be reserved for more elderly patients due to higher revision rates in younger patients. To determine our UKR revision rates at the Great Western Hospital we requested knee arthroplasty data from the NJR, Hospital Episode Statistics (HES) data submitted by our centre to the Primary Care Trust, and interrogated our internal theatre implant database. This revealed significant discrepancies between different data sources. We collected data from each source for 2005, 2006, and 2007. Operations were classified as TKR, UKR, Other or Unspecified. Results are illustrated in the attached table: Key findings: Our theatre implant database appears most accurate and includes a greater number of joint replacement operations than NJR or HES data and fewer ‘unspecified’ procedures. On average 15% NJR, 0% HES and 0.3% theatre data procedures were ‘unspecified’. NJR data comprises an average 17 fewer, and HES data an average 36 fewer procedures each year compared with our theatre data. Up to 80% UKRs performed are recorded as TKR in HES data. In summary there is significant inaccuracy in our NJR data which may affect the validity of conclusions drawn from NJR data analysis. HES data is even less accurate with implications for hospital funding. We strongly advise other centres to continue to maintain accurate implant data and to perform a similar audit to calculate error rates for NJR and HES data. Further analysis is required to identify at which stage of data collection inaccuracies occur so that solutions can be devised. We are currently analysing data from 2008 and 2009.
Unicompartmental knee replacement (UKR) is an established treatment for single compartment end-stage arthrosis with good recorded survivorship. UKRs are often implanted into more active younger patients, but patient selection remains controversial. A recent study, led by the Royal College of Surgeons Clinical Effectiveness Unit, demonstrated that prosthesis revision rates decrease strongly with age (Van Der Meulen et al 2008). It has therefore been suggested that UKR should only be considered in elderly patients. This contrasts our observed experience of early revision cases leading us to compare these patients with a control group. Between September 2002 and 2008, 812 Oxford Mobile Bearing Medial UKRs were implanted. We compared all patients who underwent UKR revision to Total Knee Replacement (TKR) against a control group of 50 consecutive UKR patients. 20 implants have required revision to TKR in 19 patients since 2002. Median age at index surgery was 68 (range 48-81), median BMI was 31 (range 25-41.5), 17 patients were female (85%), and median implant survival was 25 months (range 6-57). Control group median age at index surgery was 66 (range 46-81), median BMI was 30 (range 22-51), and 27 patients were female (54%). Median Oxford Knee Score recorded in September 2009 was 36 (range 14-54) for revision patients and 21 (range 14-39) for the control group (p=0.021). Our UKR patients with early failure requiring revision are far more likely to be female (p=0.015), as well as older and with a higher BMI than the control group. We feel this is a subset of patients at high risk of failure, despite meeting all criteria for UKR. The underlying causes are likely to be multifactorial, but a key factor may be that this group has varus tricompartment osteoarthritis rather than classical anteromedial osteoarthritis. Our data counters recent advice based on National Joint Registry data.
The Oxford mobile bearing unicompartmental knee replacement (UKR) is a validated, highly successful implant with an excellent ten-year survivorship. From November 2001 to September 2006 three hundred and eighty two patients who had a medial cemented Oxford Unicompartmental knee replacement (Biomet, Bridgend, UK) via a minimally invasive approach were prospectively entered into a database and followed up as per departmental policy in the specialist joint assessment clinic. We have noted a minority of patients have persistent postoperative pain and/or mechanical symptoms resistant to the standard postoperative therapies. We report the outcome of 22 patients who had an arthroscopy for persistent pain and/or mechanical symptoms a median of 15 months (range 4 months – 31 months) following medial unicompartmental knee replacement. The median follow up time following arthroplasty was 38 months (range 16 months – 63 months). Post arthroscopy we divided our study patients into two groups; those who had an improvement in symptoms and those who had none. These groups were then compared, with particular reference to demographics, check radiographs and arthroscopic findings. The results showed that patients with anterior or anteromedial symptoms in whom a medial rim of scar tissue was identified and debrided sixty seven percent had a significantly increased probability of symptomatic improvement (p<0.005). In addition men appeared to significantly improve more that women (p<0.043). When performed this therapeutic intervention many prevent or at least defer the need for early revision to total knee replacement in some cases and we have no complications as a result of the arthroscopic intervention. This observational study provides evidence for a role for arthroscopy in selected patients with pain following unicompartmental knee replacement.
