Does robotic surgical assistant (ROSA) functionally aligned TKA lead to higher satisfaction than conventional mechanically aligned TKA: A propensity-matched pair analysis.

Abstract

Total knee arthroplasty (TKA) is the established treatment for severe knee osteoarthritis, with robotic-assisted TKA (rTKA) proposed to enhance surgical precision and potentially improve outcomes. This study investigates whether functionally-aligned rTKA using the ROSA Knee System results in superior functional outcomes and patient satisfaction compared to conventional mechanically aligned TKA (mTKA). We conducted a retrospective, propensity-score matched cohort study including 154 patients (46 rTKA, 108 mTKA) who underwent primary TKA by a single surgeon from October 2020 to October 2023. Functionally-aligned (FA) rTKA was performed using the ROSA Knee System. Patients were assessed using the Short-Form 36 (SF36), Knee Society Knee Score (KSKS), Knee Society Function Score (KSFS), and Oxford Knee Score (OKS) preoperatively and at 6 months postoperatively. Immediate postoperative outcomes such as pain at rest and movement, ambulation distance, and range of motion were measured. Statistical analysis evaluated results at a 95 % confidence interval, with significance at <i>P</i> < 0.05. No significant differences were observed in immediate postoperative pain at rest (<i>P</i> = 0.988), pain during movement (<i>P</i> = 0.634), ambulation distance (<i>P</i> = 0.243), and range of motion (<i>P</i> = 0.752) between the groups. At 6 months, there were no significant differences between rTKA and mTKA in achieving the minimal clinically important difference for SF36 (<i>P</i> = 0.996), KSKS (<i>P</i> = 0.150), KSFS (<i>P</i> = 0.091), and OKS (<i>P</i> = 0.949). No significant differences were noted for satisfaction levels (<i>P</i> = 0.315) and fulfilled expectations (<i>P</i> = 0.557) between both groups. At 6 months postoperatively, FA rTKA demonstrated equivalent outcomes and satisfaction levels compared to mTKA. Future research should focus on examining longer-term follow-up outcomes, quantifying gap balance in MA mTKA to allow direct comparison with rTKA and studying alternative personalised alignment rTKA strategies to enhance patient outcomes.