Cost-utility analysis of robotic and conventional total knee arthroplasty: A 200-patient micro-costing study in a public sector institution
摘要
Robotic-arm assisted total knee arthroplasty (RO TKA) has been developed to improve surgical precision and reproducibility compared with conventional techniques. However, the economic implications of adopting robotic technology remain uncertain, particularly within publicly funded healthcare systems. This study aimed to evaluate the in-hospital costs and health-related quality of life outcomes associated with RO TKA compared with conventional TKA (CO TKA) using a cost-utility framework within a UK National Health Service (NHS) institution. A propensity-matched cohort cost-utility analysis was performed including 200 patients undergoing primary TKA for end-stage osteoarthritis at a single high-volume tertiary centre. 100 patients underwent RO TKA and 100 underwent CO TKA, matched 1:1 for age, sex and American Society of Anesthesiologists (ASA) grade. Direct in-hospital costs were obtained using a micro-costing approach. Health-related quality of life was measured using the EQ-5D-3 L preoperatively and at one year postoperatively to estimate quality-adjusted life years (QALYs). The primary outcome was the incremental cost-effectiveness ratio (ICER). Deterministic and probabilistic sensitivity analyses were performed to assess uncertainty. Mean total in-hospital costs were higher for RO TKA compared with CO TKA (£6,517 vs. £6,204), representing an incremental cost of £313 per patient. Patients undergoing RO TKA demonstrated a significantly shorter length of stay (2.3 vs. 3.1 days; p = 0.008) and lower ward (p = 0.029) and drug and pharmacy (p = 0.041) costs. One-year postoperative EQ-5D-3 L scores were higher in the RO TKA cohort (0.82 vs. 0.75; p < 0.001), resulting in a greater mean QALY gain (0.192 vs. 0.140). The incremental QALY gain of 0.052 produced an ICER of £6,019 per QALY gained, well below the National Institute for Health and Care Excellence (NICE) willingness-to-pay threshold of £20,000–£30,000 per QALY. Sensitivity analyses confirmed the robustness of these findings. RO TKA demonstrated improved postoperative health utility and is likely to achieve cost-effectiveness despite modestly higher upfront costs. Within a publicly funded healthcare system, RO TKA is likely to represent a clinically and economically viable innovation in knee arthroplasty, under the costing assumptions applied in this analysis.