OVERALL PAIN IS THE MOST IMPORTANT PREDICTOR OF PATIENT SATISFACTION FOLLOWING TOTAL AND UNICOMPARTMENTAL KNEE ARTHROPLASTY

Aims The Oxford Knee Score (OKS) is a validated questionnaire for measuring outcomes following knee arthroplasty. Of the 12 individual questions, some may have more clinical importance than others. The aim of this study was to identify the OKS question(s) most associated with patient satisfaction to inform clinical practice and future research. Patients and methods The New Zealand Joint Registry (NZJR) has captured patient satisfaction data for all knee arthroplasty patients since 2021. A total of 9,384 total knee (TKA) and 2,424 unicompartmental knee arthroplasty (UKA) with satisfaction scores recorded in the NZJR up to 15-year follow-up were included. Associations between individual OKS questions and satisfaction were assessed using logistic regression and receiver operating characteristic analyses. Results The most important question associated with patient satisfaction was on ‘overall pain’ for both TKA (6 months: odds ratio (OR) 1.6, p<0.01; 5 years: OR 1.5, p=0.04; 10 years: OR 1.7, p=0.02; 15 years: OR 1.7, p=0.05) and UKA (6 months: odds ratio (OR) 1.9, p<0.01; 5 years: OR 2.0, p=0.01; 10 years: OR 1.7, p=0.15; 15 years: OR 1.4, p=0.49). Additional questions found to be associated with satisfaction were ‘getting in and out of the car’, ‘limping when walking’ and ‘knee giving way’, however these were mostly limited to TKA patients at early to mid-term follow-up (prior to 5 years). Conclusion The best predictor of patient satisfaction following knee arthroplasty was ‘overall pain’. Future research and clinical practice focused on improving knee arthroplasty patient satisfaction should take into consideration patients’ level of post-operative pain.