Total Knee Arthroplasty Hospital Costs by Time-Driven Activity-Based Costing: Robotic vs Conventional

Background: Total knee arthroplasty (TKA) represents a major national health expenditure. The last decade has seen a surge in robotic-assisted TKA (roTKA); however, literature on the costs of roTKA as compared to conventional TKA (cTKA) is limited. The purpose of this study was to assess the costs associated with roTKA as compared to cTKA.Methods: This was a retrospective cohort cost-analysis study of patients undergoing primary, elective roTKA or cTKA from July 2020 to March 2021. Time-driven activity-based costing (TDABC) was used to determine granular costs. Patient demographics, medical/surgical details, and costs were compared. Results: A total of 2058 TKAs were analyzed (1795 cTKAs and 263 roTKAs). roTKA patients were more often male (50.2% vs 42.3%; P = .016), and discharged home (98.5% vs 93.7%; P = .017), and had longer operating room (OR) time (144.6 vs 130.9 minutes; P < .0001), and lower length of stay (LOS) (1.8 vs 2.1 days; P < .0001). roTKA costs were 2.17x greater for supplies excluding implant (P < .0001), 1.18x for total supplies (P < .0001), 1.12x for OR personnel (P < .0001), and 1.05x for total personnel (P = .0001). Implant costs were similar (P = .076), but 0.98x cheaper for post-anesthesia care unit personnel (P =.018) and 0.84x for inpatient personnel (P < .0001). Overall hospital costs for roTKA were 1.10x more than cTKA (P < .0001).Conclusion: roTKA had higher total hospital costs than cTKA. Despite a lower LOS, the longer OR time with higher supply and personnel costs resulted in a costlier procedure. Understanding the costs of roTKA is essential when considering the value (ie, outcomes per dollars spent) of this modern technology.(c) 2021 The Authors. Published by Elsevier Inc. on behalf of The American Association of Hip and Knee Surgeons. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/ licenses/by-nc-nd/4.0/).