Kage Tomofumi, Kono Kenichi, Tomita Tetsuya, Yamazaki Takaharu, Taketomi Shuji, Yamagami Ryota, Kawaguchi Kohei, Murakami Ryo, Arakawa Takahiro, Kobayashi Takashi, Inui Hiroshi, Tanaka Sakae
Department of Orthopaedic Surgery, Faculty of Medicine The University of Tokyo Bunkyo-ku Tokyo Japan.
Graduate School of Health Sciences Morinomiya University of Medical Sciences Osaka Japan.
J Exp Orthop. 2024 Dec 18;11(4):e70013. doi: 10.1002/jeo2.70013. eCollection 2024 Oct.
The efficacy of medial pivot total knee arthroplasty (MP TKA) in treating valgus knees that may cause medial instability is unknown. The purpose of this study was to investigate the in vivo kinematics of MP TKA for the valgus knees and compare them to those for the varus knees.
The kinematics of 19 valgus knees and 19 varus knees operated in the MP TKA were investigated under fluoroscopy during squatting using a two- to three-dimensional registration technique. Accordingly, the valgus and varus knees were evaluated and compared in terms of knee flexion angle, anteroposterior translation for the medial and lateral low contact points, axial rotation and valgus-varus angle of the femoral component relative to the tibial component, as well as kinematic pathways.
The knee flexion angle was found to be identical in both knees. There was no anterior translation on the medial side of the valgus knees, and no difference was detected between the two knees. On the lateral side, posterior translation was observed in both knees, with no difference between the two. Femoral external rotation was observed in both knees, and no difference was detected between the two. There was no valgus-varus change in the valgus knees, nor was there a difference between the two knees. The valgus knees demonstrated MP motion, whereas the varus knees demonstrated MP motion and bicondylar rollback.
The medial side of the valgus knees treated with MP TKA showed comparable stable kinematics to the varus knees. The MP TKA is an effective procedure for valgus knees to stabilize the medial compartment.
Level Ⅲ.
内侧旋转全膝关节置换术（MP TKA）治疗可能导致内侧不稳定的外翻膝的疗效尚不清楚。本研究的目的是研究MP TKA治疗外翻膝的体内运动学，并将其与内翻膝的运动学进行比较。
采用二维到三维配准技术，在透视下对19例接受MP TKA手术的外翻膝和19例内翻膝在蹲坐过程中的运动学进行研究。据此，从膝关节屈曲角度、内侧和外侧低接触点的前后平移、股骨部件相对于胫骨部件的轴向旋转和内外翻角度以及运动路径等方面对外翻膝和内翻膝进行评估和比较。
发现两组膝关节的屈曲角度相同。外翻膝内侧无向前平移，两组之间未检测到差异。在外侧，两组膝关节均观察到向后平移，两者之间无差异。两组膝关节均观察到股骨外旋，两者之间未检测到差异。外翻膝无内外翻变化，两组之间也无差异。外翻膝表现为MP运动，而内翻膝表现为MP运动和双髁后滚。
MP TKA治疗的外翻膝内侧显示出与内翻膝相当的稳定运动学。MP TKA是稳定外翻膝内侧间室的有效手术方法。
Ⅲ级。
