PATIENT-REPORTED OUTCOME FOLLOWING METAL-ON-METAL RESURFACING OF THE HIP AND TOTAL HIP REPLACEMENT

Abstract

Introduction: Patient-reported outcome and satisfaction scores have become increasingly important in evaluating successful surgery. There is continued enthusiasm for metal-on-metal resurfacing of the hip, particularly as an alternative to total hip replacement (THR) in young, active patients with osteoarthritis. However, although mid-term survivorship data is promising, it remains unclear whether patient-reported outcomes following resurfacing match those following THR.

Patients and Methods: This case-matched control study compared patient-reported outcome and satisfaction data following hip resurfacing and total hip arthroplasty. Thirty-three consecutive patients selected for hip resurfacing were compared with 99 patients undergoing cemented total hip replacement (THR), matched for age, sex and pathology. Participants completed a Short-Form 12 Health Survey (SF-12) and Oxford Hip Score (OHS) questionnaire pre-operatively and 6 months post operatively, with an additional patient satisfaction questionnaire.

Results: There was no difference in length of hospital stay. Both groups reported improved outcome scores, with mean OHS improvements of 19.5 (95% CI: 17.0–22.1), and 20.6 (95% CI: 18.6–22.5) following resurfacing and THR respectively. There were similar improvements in SF-12 PCS of 14.2 (95% CI: 9.5 to 14.2) and 15.2 (95% CI: 13.2 to 18.2) for the resurfacing and THR groups respectively. The improvement in outcome scores did not differ between the two groups on multivariate regression analysis (P=0.509 for OHS, P=0.629 for SF-12 PCS). Both groups reported high levels of satisfaction, which tended to be better in patients undergoing hip resurfacing (97.0% vs 92.9%), with resurfacing patients reporting better pain relief (P=0.022) and better heavy lifting (P=0.038) at 6 months.

Discussion: This study shows that the short-term patient-centred outcome scores for hip resurfacing are at least as good as for conventional hip replacement, with slightly higher levels of satisfaction.