National trends in total and unicompartmental knee arthroplasty: 2020 to 2022

Total knee arthroplasty (TKA) and unicompartmental knee arthroplasty (UKA) are essential treatments for osteoarthritis, with each offering distinct advantages. Advances in TKA and UKA have allowed for a transition from inpatient to outpatient surgical settings. In the wake of this transition, new techniques integrating robotic assistance (RA) have arisen, but clinical benefit over conventional techniques is uncertain. The objective was to assess how technological advancements and changing surgical environments have shaped the delivery and adoption of TKA and UKA.

This retrospective cohort study utilized the MarketScan Commercial Claims Database to identify patients who underwent primary unilateral TKA or UKA for osteoarthritis between April 1, 2020-December 31, 2022. Demographic, geographic, and hospital setting data were analyzed. RA procedures were identified using specific CPT codes, and further classified based on preoperative CT scans obtained within 90 days. Statistical analyses were conducted using STATA.

Among the 85,265 patients included (79,711 TKA; 5554 UKA), 13,194 underwent robotic-assisted procedures. The percentage of procedures conducted in the ambulatory surgery (ASC) setting for both TKA and UKA increased (p < 0.001). Surgeons were more likely to use RA for TKA (p < 0.001) and for UKA (p = 0.006). Inpatient and ASC TKAs were more likely to use CT-guided RA (p < 0.05). CT-based robotic assisted UKA remained stable with respect to time(p > 0.3).

The landscape of TKA and UKA is evolving, with a rise in the number of procedures being performed in the ASC setting. This trend has been supported by the increasing integration of robotic-assisted technology into TKA and UKA, despite increased costs. Even though RA UKA is increasing in overall, CT-guided RA UKA specifically has not increased. Despite the anticipated growth in robotic-assisted procedures, conventional techniques and non-CT-based technologies continue to be widely favored.