To examine health-related quality of life (HRQoL) after total knee replacement (TKR) or unicompartmental knee arthroplasty (UKA).
Asian adult patients undergoing either TKR or UKA in a hospital in Singapore between 2001 and 2006 were interviewed before surgery and 6 and 24 months postoperatively to obtain demographic information and HRQoL scores using the Short Form-36 Health Survey (SF-36) and the Oxford Knee Score (OKS).
Data were collected from 2243, 1715, and 1113 patients at baseline and at 6 and 24 months, respectively. TKR patients had a lower preoperative OKS than UKA patients and lower preoperative scores on four subscales of the SF-36 (P < 0.01). Both TKR and UKA patients' OKS and SF-36 subscale scores improved 6 months postoperatively except in the general health domain. SF-36 role physical and bodily pain scores showed the most improvement (40.9 and 33.0 points in TKR and 36.9 and 31.4 points in UKA patients, respectively). Two years after surgery, TKR patients' SF-36 scores and OKSs were not significantly different from those of UKA patients except for physical functioning scores. Multiple regression analysis adjusting for demographics showed that baseline scores were a significant predictor of the postoperative OKSs and scores on all SF-36 subscales (P < 0.01), whereas the type of surgery was not associated with the postoperative scores.
Both TKR and UKA patients experienced significant improvements in HRQoL, particularly in the role physical and pain domains. After controlling for potential confounding variables, the type of surgery was not a significant predictor of patients' postoperative HRQoL scores.