Leg positioner improves efficiency on selected steps in robotic-assisted total knee arthroplasty: an analysis of...

Robotic-assisted total knee arthroplasty (TKA) improves surgical precision and reproducibility. Leg positioners are used to stabilize the limb and support workflow, but their impact in robotic-assisted TKA remains unclear. This study examined whether leg positioner use influences surgical efficiency, workflow, and team experience. A retrospective non randomized single-center analysis was conducted on 79 robotic-assisted TKAs performed between 2018 and 2023 with the MAKO system. Fifty-seven procedures (72%) used a leg positioner, while 22 (28%) served as a control group. Three senior surgeons performed the operations, with step durations and system interactions recorded by independent observers. Surgical phases were divided into preparation, cut-to-suture, and wrap-up, and further into robotic-assisted and conventional steps. Postoperative questionnaires based on the NASA-TLX framework were completed by surgeons and scrub technicians. Median cut-to-suture time was 1:29 h, with no significant difference between leg positioner (1:25 h) and control cases (1:35 h, p = 0.251). Robotic-assisted steps (0:28 h) were unaffected (p = 0.763), while conventional steps were significantly longer without the leg positioner (0:41 h vs. 0:34 h, p = 0.006). Sub-analysis showed slower bone registration and robot positioning with the leg positioner, but faster final implantation (3 vs. 5 min, p < 0.001) and suturing (16 vs. 19 min, p = 0.027). Questionnaires indicated high satisfaction overall, though surgeons reported reduced ease of robotic arm operation and confidence in ligament balancing. The leg positioner redistributed time across surgical steps rather than improving overall efficiency. It offers stability benefits but may restrict intraoperative flexibility. Further studies should address ergonomics, cost-effectiveness, and long-term outcomes.