Department of Medical Biophysics, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada; Imaging Research Laboratories, Robarts Research Institute, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada; Surgical Innovation Program, Lawson Health Research Institute, London, Ontario, Canada.
Division of Orthopaedic Surgery, Department of Surgery, Schulich School of Medicine and Dentistry, Western University and London Health Sciences Centre, London, Ontario, Canada.
J Arthroplasty. 2020 Jan;35(1):272-277. doi: 10.1016/j.arth.2019.07.046. Epub 2019 Aug 6.
There is controversy regarding the superiority of posterior-stabilizing (PS) total knee arthroplasty (TKA) and cruciate-retaining (CR) TKA. Substantial work has made comparisons between PS and CR TKA at follow-ups of less than 5 years. It was the goal of the present study to compare the kinematics at greater than 5 years postoperatively between CR and PS TKA, with a secondary goal of comparing patient function.
A total of 42 knees were investigated, with equal representation in the PS and CR TKA groups. Patients underwent radiostereometric analysis imaging at 0°, 20°, 40°, 60° 80°, and 100° of flexion. Contact position, magnitude of excursion, and condylar separation on each condyle were measured. A Timed-Up-and-Go functional test was also performed by patients, with the total test time being measured. Preoperative and postoperative clinical outcome scores were also collected.
There were differences in contact position on both the medial and lateral condyles at multiple angles of flexion (P < .05). There was no difference (P = .89) in medial excursion; however, PS TKA had greater lateral excursion than CR TKA (P < .01). No difference (P > .99) was found in frequency of condylar separation. PS TKA was associated with faster (P = .03) total Timed-Up-and-Go test times. There were no differences in clinical outcome scores between the groups preoperatively or postoperatively.
We found kinematic and functional differences that favor PS TKA. Our results suggest posterior cruciate ligament insufficiency in CR TKA, indicating that perhaps the cam/post systems in PS TKA better maintain knee kinematics and function long term.
关于后稳定（PS）全膝关节置换术（TKA）和保留交叉韧带（CR）TKA 的优越性存在争议。大量研究已经在随访时间少于 5 年的情况下对 PS 和 CR TKA 进行了比较。本研究的目的是比较 CR 和 PS TKA 术后超过 5 年的运动学，次要目标是比较患者的功能。
共纳入 42 例膝关节，PS 和 CR TKA 组各有 21 例。患者在 0°、20°、40°、60°、80°和 100°屈曲时接受放射立体测量分析成像。测量每个髁的接触位置、活动度大小和髁间分离。患者还进行了计时起立行走功能测试，测量总测试时间。还收集了术前和术后的临床结果评分。
在多个屈曲角度下，内侧和外侧髁的接触位置存在差异（P<.05）。内侧活动度没有差异（P=.89）；然而，PS TKA 的外侧活动度大于 CR TKA（P<.01）。髁间分离的频率没有差异（P>.99）。PS TKA 与更快的总计时起立行走测试时间相关（P=.03）。两组患者术前和术后的临床结果评分均无差异。
我们发现了有利于 PS TKA 的运动学和功能差异。我们的结果表明 CR TKA 中后交叉韧带功能不全，这表明 PS TKA 中的凸轮/后稳定系统可能更好地长期维持膝关节的运动学和功能。
