Sensor-guided robot-assisted TKA more precisely achieves targeted functional knee phenotypes than conventional robotic-assisted technique.

Abstract

This study conducted a comparison between sensor-guided robotic-assisted (SGR) total knee arthroplasty (TKA) and conventional robotic-assisted (ConR) TKA. The objective was to determine whether the SGR protocol yields superior restoration of targeted knee phenotypes and clinical outcomes. A total of 77 primary TKAs (July 2023-March 2024) were analyzed, comprising the SGR group (n = 40) and ConR group (n = 37) on the same platform. The SGR group followed a planned asymmetric gap target of 17 mm (medial) and 18 mm (lateral) through bony resection, with subsequent sensor-guided soft-tissue release to achieve L‑FKPext‑neutr/L‑FKPflex‑neutr, medial pressure > lateral pressure and ICPD 0-66.0 N. In contrast, the ConR group targeted symmetric 18 mm gaps and used the sensor for data collection only, without feedback. Bony and laxity phenotypes were recorded. Outcomes included VAS, KSS and a 5‑item satisfaction survey. The SGR group achieved higher L-FKPext-neutr/L-FKPflex-neutr rates (p < 0.001) and required more soft tissue releases (85% vs. 43.2%, p < 0.001). At 12 months, SGR group demonstrated superior pain relief (VAS: 1.3 ± 0.9 vs. 1.7 ± 0.6, p = 0.013) and functional outcomes (KSS: 89.2 ± 5.1 vs. 86.9 ± 5.3, p = 0.042). Both groups showed comparable alignment with no complications. The SGR protocol was successful in precisely targeting specific intraoperative bony and laxity phenotypes, without increasing complication risks. Further research is needed to determine if these improvements reach the minimal clinically important difference for long-term postoperative outcomes. Level III.