Supervised neuromuscular exercise prior to hip and knee replacement: 12-month clinical effect and cost-utility analysis alongside a randomised controlled trial

Purpose: To analyse cost-utility of supervised neuromuscular exercise prior to total hip replacement (THR) and total knee replacement (TKR). Methods: Cost-utility analysis was performed alongside a randomised controlled trial including 165 patients scheduled for THR or TKR (Clinical Trials registration no.: NCT01003756). An 8-week preoperative supervised neuromuscular exercise program was provided twice weekly in addition to standard THR or TKR regimen compared to standard THR and TKR regimen alone. The analysis applied the health care sector perspective and used the intention-to-treat approach. The intervention cost was based on tariff-based costs for physiotherapy. Individual resource use and tariff-based costs (2012-EUR) for health care visits in primary and secondary care were extracted from The Danish National Health Insurance Service Registry and The Danish National Health Registry. Utility was expressed as quality adjusted life years (QALY), based on weighted EQ-5D-3L scores. Missing EQ-5D-3L data was imputed with the linear trend at point method. Incremental net monetary benefit was analysed to estimate the probability for the intervention being cost effective and presented in cost effectiveness acceptability curve (CEAC). The robustness of the cost-utility result was tested by changing perspective, applying a per-protocol analysis and limiting analysis to complete item response. The time horizon was 61 weeks including assessment of clinical outcomes at baseline, post-intervention, and 6 weeks, 3 months and 12 months post-surgery. Results: A non-significant total cost of €132 (95CI -3942 to 3679) was observed between the groups. There was a significant QALY gain of 0.06 (95CI, 0.02 to 0.09) in the intervention group as compared to the control group. At the conventional threshold of €40.000, the intervention was found to be cost effective at 89utility analysis was found to be robust (Figure). Conclusions: Preoperative supervised neuromuscular exercise was cost-effective in patients scheduled for THR and TKA surgery at conventional thresholds for willingness to pay.