Gil Jorge N, Gray Chancellor F, Prieto Hernan A, Parvataneni Hari K, Miley Emilie N, Rutledge Rachel S, Horodyski Mary B, Deen Justin T
Department of Orthopaedic Surgery, College of Medicine, University of Florida, Gainesville, Florida.
Florida Orthopaedic Institute, Gainesville, Florida.
J Arthroplasty. 2025 Sep;40(9):2303-2308. doi: 10.1016/j.arth.2025.02.039. Epub 2025 Feb 17.
Postoperative knee range of motion (ROM) is among the most frequently reported functional metrics following total knee arthroplasty (TKA). Despite the major use of ROM as a metric, minimal literature exists assessing the progression of motion postoperatively over time or its implications on patient-reported outcome measures. As such, this study aimed to: (1) determine the recovery trajectory in knee ROM during the first year following primary TKA; and (2) determine if a correlation existed between patients' ROM recovery trajectory and patient-reported outcome measure scores.
Data were collected prospectively on all patients undergoing a unilateral primary TKA between 2017 and 2019. Standardized goniometric measurements were used to measure knee flexion and extension at five time points: preoperatively, intraoperatively, and postoperatively at two weeks, six weeks, and one year. In addition, the Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR) was collected preoperatively and at the 1-year postoperative visit. A total of 306 TKA procedures were performed on 269 patients, and of those patients, 63.9% (N = 172) were women and 36.1% (N = 97) were men who had a mean age of 67 years (range, 29 to 89) and a mean body mass index of 30.8 (range, 18.2 to 49.0).
Mean knee flexion significantly increased from 112.8 (range, 63.0 to 140.0) degrees preoperatively to 119.0 (range, 95.0 to 140.0) degrees at one year postoperatively (mean difference = 4.61, P < 0.001). More specifically, 97.4% of flexion was restored by six weeks (111.2; range, 58.0 to 132.0) postoperatively. Knee extension also significantly improved from 5.9 (range, -5.0 to 32.0) degrees to 0.9 (range, 0 to 8.0) degrees at 1-year follow-up (mean difference = 5.03, P < 0.001). A weak positive correlation existed between preoperative ROM and KOOS JR scores (r = 0.24, P < 0.01).
Knee flexion ROM is restored in a nonlinear trajectory following a primary TKA, with over 90% of the progress occurring within the first six weeks postoperatively. In contrast, knee extension ROM is restored in a more linear manner. At one year postoperatively, target ROM fell between preoperative and intraoperative measurements. Neither ROM nor the recovery trajectory of motion correlates with KOOS JR scores. As such, this information can be valuable when attempting to set expectations for patient recovery.
Level II, Prospective cohort study.
术后膝关节活动范围（ROM）是全膝关节置换术（TKA）后最常报告的功能指标之一。尽管ROM作为一项指标被广泛使用，但评估术后随着时间推移运动进展情况或其对患者报告结局指标影响的文献却很少。因此，本研究旨在：（1）确定初次TKA后第一年膝关节ROM的恢复轨迹；（2）确定患者的ROM恢复轨迹与患者报告结局指标得分之间是否存在相关性。
前瞻性收集2017年至2019年间所有接受单侧初次TKA患者的数据。采用标准化测角法在五个时间点测量膝关节屈伸：术前、术中、术后两周、六周和一年。此外，术前和术后1年随访时收集膝关节损伤和骨关节炎关节置换结局评分（KOOS JR）。共对269例患者进行了306例TKA手术，其中63.9%（N = 172）为女性，36.1%（N = 97）为男性，平均年龄67岁（范围29至89岁），平均体重指数30.8（范围18.2至49.0）。
平均膝关节屈曲度从术前的112.8°（范围63.0至140.0°）显著增加到术后一年的119.0°（范围95.0至140.0°）（平均差值 = 4.61，P < 0.001）。更具体地说，术后六周时97.4%的屈曲度得到恢复（111.2°；范围58.0至132.0°）。膝关节伸展度在1年随访时也从5.9°（范围 -5.0至32.0°）显著改善到0.9°（范围0至8.0°）（平均差值 = 5.03，P < 0.001）。术前ROM与KOOS JR评分之间存在弱正相关（r = 0.24，P < 0.01）。
初次TKA后膝关节屈曲ROM以非线性轨迹恢复，超过90%的进展发生在术后前六周内。相比之下，膝关节伸展ROM以更线性的方式恢复。术后一年时，目标ROM介于术前和术中测量值之间。ROM及其运动恢复轨迹均与KOOS JR评分无关。因此，在试图为患者恢复设定预期时，这些信息可能很有价值。
二级，前瞻性队列研究。
