Cost-effectiveness of total hip arthroplasty versus resurfacing arthroplasty: economic evaluation alongside a clinical trial

Objectives: To report on the relative cost-effectiveness of total hip arthroplasty and resurfacing arthroplasty (replacement of articular surface of femoral head only) in patients with severe arthritis suitable for hip joint resurfacing arthroplasty. Design: Cost-effectiveness analysis (cost per QALY) on an intention to treat basis of a singlecentre, single-blind randomised controlled trial of 126 adult patients within 12 months of treatment. Missing data was assessed using multiple imputations with differences in baseline quality of life and gender adjusted using regression techniques. Setting: A large teaching hospital trust in the UK Participants: 126 adult patients with severe arthritis of the hip joint suitable for a resurfacing arthroplasty of the hip. Results: Data was received for 126 patients, 4 of whom did not provide any resource use data. For the remainder, data was imputed for costs or quality of life in at least one time point (baseline, 3 months, 6 months, 1 year) for 18 patients. Patients in the resurfacing arm had higher quality of life at 12 months (0.795 vs. 0.727) and received 0.033 more QALYs within the first 12 months post operation. At an additional cost of £410, resurfacing arthroplasty offers benefits at £12,374 per QALY within the first 12 months of treatment.When covariates are considered, the health economic case is stronger in men than women. Conclusions: Resurfacing arthroplasty appears to offer very short term efficiency benefits over total hip arthroplasty within a selected patient group. This conclusion should be tested over a longer period through longer series following up resurfacing arthroplasty and through decision analytic modelling.