scholarly journals New surgical instrumentation reduces the revision rate of unicompartmental knee replacement: A propensity score matched comparison of 15,906 knees from the National Joint Registry

The Knee ◽  
2020 ◽  
Vol 27 (3) ◽  
pp. 993-1002 ◽  
Author(s):  
Hasan R. Mohammad ◽  
Gulraj S. Matharu ◽  
Andrew Judge ◽  
David W. Murray
Keyword(s):  
Propensity Score ◽  
Knee Replacement ◽  
Revision Rate ◽  
Unicompartmental Knee Replacement ◽  
National Joint Registry ◽  
Joint Registry ◽  
Surgical Instrumentation ◽  
Unicompartmental Knee ◽  
Matched Comparison

scholarly journals Most unicompartmental knee replacement revisions could be avoided: a radiographic evaluation of revised Oxford knees in the National Joint Registry

2020 ◽  
Vol 28 (12) ◽  
pp. 3926-3934 ◽  
Author(s):  
James A. Kennedy ◽  
Jeya Palan ◽  
Stephen J. Mellon ◽  
Colin Esler ◽  
Chris A. F. Dodd ◽  
...  
Keyword(s):  
Surgical Technique ◽  
Knee Replacement ◽  
Lateral Compartment ◽  
Radiographic Evaluation ◽  
Unicompartmental Knee Replacement ◽  
National Joint Registry ◽  
Level Of Evidence ◽  
Joint Registry ◽  
Unexplained Pain ◽  
Unicompartmental Knee

Abstract Purpose The purpose of this study was to understand why the revision rate of unicompartmental knee replacement (UKR) in the National Joint Registry (NJR) is so high. Using radiographs, the appropriateness of patient selection for primary surgery, surgical technique, and indications for revision were determined. In addition, the alignment of the radiographs was assessed. Methods Oxford UKR registered with the NJR between 2006 and 2010 and subsequently revised were identified by the NJR. A blinded review was undertaken of pre-primary, post-primary, and pre-revision anteroposterior and lateral radiographs of a sample of 107 cases from multiple centres. Results The recommended indications were satisfied in 70%, with 29% not demonstrating bone-on-bone arthritis. Major technical errors, likely leading to revision, were seen in 6%. Pre-revision radiographs were malaligned and, therefore, difficult to interpret in 53%. No reason for revision was seen in 67%. Reasons for revision included lateral compartment arthritis (10%), tibial loosening (7%), bearing dislocation (7%), infection (6%), femoral loosening (3%), and peri-prosthetic fracture (2%, one femoral, one tibial). Conclusions Only 20% of the revised UKR were implanted for the recommended indications, using appropriate surgical technique and had a mechanical problem necessitating revision. One-third of primary surgeries were undertaken in patients with early arthritis, which is contraindicated. Two-thirds were presumably revised for unexplained pain, which is not advised as it tends not to help the pain. This study suggests that variable and inappropriate indications for primary and revision surgery are responsible for the high rates of revision seen in registries. Level of evidence III, Therapeutic study.

scholarly journals Unicompartmental compared with total knee replacement for patients with multimorbidities: a cohort study using propensity score stratification and inverse probability weighting

2021 ◽  
Vol 25 (66) ◽  
pp. 1-126
Author(s):  
Albert Prats-Uribe ◽  
Spyros Kolovos ◽  
Klara Berencsi ◽  
Andrew Carr ◽  
Andrew Judge ◽  
...  
Keyword(s):  
Propensity Score ◽  
Total Knee Replacement ◽  
Knee Replacement ◽  
Inverse Probability Weighting ◽  
Unicompartmental Knee Replacement ◽  
Probability Weighting ◽  
Inverse Probability ◽  
Unicompartmental Knee ◽  
Total Knee ◽  
Propensity Score Stratification

Background Although routine NHS data potentially include all patients, confounding limits their use for causal inference. Methods to minimise confounding in observational studies of implantable devices are required to enable the evaluation of patients with severe systemic morbidity who are excluded from many randomised controlled trials. Objectives Stage 1 – replicate the Total or Partial Knee Arthroplasty Trial (TOPKAT), a surgical randomised controlled trial comparing unicompartmental knee replacement with total knee replacement using propensity score and instrumental variable methods. Stage 2 – compare the risk benefits and cost-effectiveness of unicompartmental knee replacement with total knee replacement surgery in patients with severe systemic morbidity who would have been ineligible for TOPKAT using the validated methods from stage 1. Design This was a cohort study. Setting Data were obtained from the National Joint Registry database and linked to hospital inpatient (Hospital Episode Statistics) and patient-reported outcome data. Participants Stage 1 – people undergoing unicompartmental knee replacement surgery or total knee replacement surgery who met the TOPKAT eligibility criteria. Stage 2 – participants with an American Society of Anesthesiologists grade of ≥ 3. Intervention The patients were exposed to either unicompartmental knee replacement surgery or total knee replacement surgery. Main outcome measures The primary outcome measure was the postoperative Oxford Knee Score. The secondary outcome measures were 90-day postoperative complications (venous thromboembolism, myocardial infarction and prosthetic joint infection) and 5-year revision risk and mortality. The main outcome measures for the health economic analysis were health-related quality of life (EuroQol-5 Dimensions) and NHS hospital costs. Results In stage 1, propensity score stratification and inverse probability weighting replicated the results of TOPKAT. Propensity score adjustment, propensity score matching and instrumental variables did not. Stage 2 included 2256 unicompartmental knee replacement patients and 57,682 total knee replacement patients who had severe comorbidities, of whom 145 and 23,344 had linked Oxford Knee Scores, respectively. A statistically significant but clinically irrelevant difference favouring unicompartmental knee replacement was observed, with a mean postoperative Oxford Knee Score difference of < 2 points using propensity score stratification; no significant difference was observed using inverse probability weighting. Unicompartmental knee replacement more than halved the risk of venous thromboembolism [relative risk 0.33 (95% confidence interval 0.15 to 0.74) using propensity score stratification; relative risk 0.39 (95% confidence interval 0.16 to 0.96) using inverse probability weighting]. Unicompartmental knee replacement was not associated with myocardial infarction or prosthetic joint infection using either method. In the long term, unicompartmental knee replacement had double the revision risk of total knee replacement [hazard ratio 2.70 (95% confidence interval 2.15 to 3.38) using propensity score stratification; hazard ratio 2.60 (95% confidence interval 1.94 to 3.47) using inverse probability weighting], but half of the mortality [hazard ratio 0.52 (95% confidence interval 0.36 to 0.74) using propensity score stratification; insignificant effect using inverse probability weighting]. Unicompartmental knee replacement had lower costs and higher quality-adjusted life-year gains than total knee replacement for stage 2 participants. Limitations Although some propensity score methods successfully replicated TOPKAT, unresolved confounding may have affected stage 2. Missing Oxford Knee Scores may have led to information bias. Conclusions Propensity score stratification and inverse probability weighting successfully replicated TOPKAT, implying that some (but not all) propensity score methods can be used to evaluate surgical innovations and implantable medical devices using routine NHS data. Unicompartmental knee replacement was safer and more cost-effective than total knee replacement for patients with severe comorbidity and should be considered the first option for suitable patients. Future work Further research is required to understand the performance of propensity score methods for evaluating surgical innovations and implantable devices. Trial registration This trial is registered as EUPAS17435. Funding This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 66. See the NIHR Journals Library website for further project information.

Sign in / Sign up

Export Citation Format

Share Document