Effects of robot-assisted total knee arthroplasty on joint function within the learning curve:a propensity score-matched study
Feng Zeyu
Xu Jiazheng
Ren Haichao
Ji Quanbo
Chen Jiying
Zhang Guoqiang
Abstract：Objective By comparing patients undergoing conventional manual total knee arthroplasty(CM-TKA)and robot-assisted total knee arthroplasty(RA-TKA)during the same period,this study aims to evaluate the learning curve and operative time of RA-TKA,assess its impact on patient outcomes,and examine whether the learning phase negatively impacts clinical outcomes.Methods A retrospective analysis was conducted on 176 TKA cases(86 RA-TKA,90 CM-TKA)performed across five Chinese medical centers from June 2023 to December 2023.The cumulative sum(CUSUM)method was used to plot the RA-TKA learning curve,stratifying cases into learning-phase and proficiency-phase groups.Total operative time,registration time,and osteotomy time were compared between the learning phase group,the proficiency phase group,and the manual group.Propensity score matching(PSM)was applied to compare postoperative 180-day range of motion(ROM)and Knee Society Score(KSS)between the manual group and the learning phase group.Results The RA-TKA learning curve demonstrated an inflection point at 8 cases.Both the learning phase group and the proficiency phase group exhibited significantly longer total operative times than the manual group(P1:156.7±26.2 min vs.101.4±23.6 min,P＜0.001;P2:115.1±22.6 min vs.101.4±23.6 min,P=0.006),though P2 showed significant reduction compared to P1(P＜0.05).Femoral/tibial registration time and femoral osteotomy time were longer in P1 than P2(P＜0.05),while tibial osteotomy time showed no difference.After PSM,41 RA-TKA learning-phase cases and 41 CM-TKA cases were matched.At 180-day follow-up,no significant differences were observed in ROM,total KSS,KSS objective score,KSS satisfaction score,KSS expectation score,or KSS functional score between learning-phase RA-TKA and CM-TKA.Conclusion RA-TKA demonstrates a distinct learning curve with initially prolonged operative times compared to CM-TKA,but efficiency improves with procedural experience.Despite extended operative durations during the learning phase,patient functional recovery and satisfaction remained unaffected,confirming the procedural safety of RA-TKA even in its early adoption stage.
Keywords：Total knee replacement surgeryRobot assisted surgeryLearning curveJoint function recovery
Publication Date：2025-06-30
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：6( 465-470 )