Bioengineering Laboratory, Department of Orthopaedic Surgery, Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, GRJ 1215, Boston, MA 02114, USA.
Int Orthop. 2012 Jul;36(7):1387-92. doi: 10.1007/s00264-011-1481-6. Epub 2012 Jan 25.
The object of this study was to investigate the in vivo function of the posterior cruciate ligament (PCL) in patients before and after a PCL-retaining total knee arthroplasty (TKA).
Eleven patients with advanced osteoarthritis (OA) of the knee were recruited. Magnetic resonance scans of each OA knee were obtained, and 3D computer models, including the femoral and tibial insertion areas of the anterolateral and posteromedial bundles of the PCL, were created. Before and after PCL-retaining TKA, dual fluoroscopic images of each knee were acquired during weight-bearing knee flexion. The images and computer models were used to reproduce the in vivo motion of the knee. The function of the PCL bundles was described in terms of elongation, elevation and deviation. Twenty-two healthy controls were also included as normal references.
PCL bundles of the OA knees were overstretched during late knee flexion and orientated more medially throughout flexion compared with normal knees. After PCL-retaining TKA, PCL bundles were further overstretched during late flexion and changed from medially directed in normal and OA knees to almost sagittally directed, which may compromise function in controlling knee rotation.
The current PCL-retaining TKA systems and surgical techniques may not adequately re-establish normal biomechanics of PCL bundles after PCL-retaining TKA.
本研究旨在探讨保留后交叉韧带（PCL）的全膝关节置换术（TKA）前后患者体内 PCL 的功能。
招募了 11 例膝关节晚期骨关节炎（OA）患者。对每位 OA 膝关节进行磁共振扫描，并创建包括 PCL 前外侧束和后内侧束股骨和胫骨插入区的 3D 计算机模型。在保留 PCL 的 TKA 前后，在负重膝关节弯曲期间获取每个膝关节的双荧光透视图像。使用这些图像和计算机模型来重现膝关节的体内运动。PCL 束的功能描述为伸长、抬高和偏离。还包括 22 名健康对照作为正常参考。
OA 膝关节的 PCL 束在膝关节晚期伸展过程中过度伸展，并且在整个伸展过程中相对于正常膝关节更向内侧定向。在保留 PCL 的 TKA 后，PCL 束在晚期伸展过程中进一步过度伸展，并且从正常和 OA 膝关节中的内侧定向变为几乎矢状定向，这可能会损害控制膝关节旋转的功能。
目前的保留 PCL 的 TKA 系统和手术技术可能无法在保留 PCL 的 TKA 后充分恢复 PCL 束的正常生物力学。
