Nakahara Hiroyuki, Okazaki Ken, Hamai Satoshi, Kawahara Shinya, Higaki Hidehiko, Mizu-uchi Hideki, Iwamoto Yukihide
Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-0054, Japan.
Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-0054, Japan.
Knee. 2015 Jun;22(3):201-5. doi: 10.1016/j.knee.2015.01.002. Epub 2015 Jan 17.
The purpose of this study is to elucidate how the rotational malalignment of prosthesis after total knee arthroplasty affects the rotational kinematics in a weight-bearing condition.
In this study of 18 knees replaced with the posterior stabilizing fixed-bearing system, which has a relatively low-restricting design, rotational angles between the femoral and tibial components and between the femur and tibia during stair climbing were evaluated in vivo in three dimensions using radiologically based image-matching techniques. Rotational alignments of the components were assessed by postoperative CT. The correlations between the rotational alignments and the rotational angles during stair climbing were evaluated.
Rotational alignment of the tibial component significantly correlated with rotational angles between the components as well as between bones during stair climbing. Rotational malalignment of the tibial component toward internal rotation caused a rotational mismatch of the tibial component toward internal rotation relative to the femoral component in 0° extension and caused a rotational mismatch of the tibia (bone) toward external rotation relative to the femur (bone). The knee in which the tibial component was placed close to the AP axis of the tibia did not show any rotational mismatch between either components or bones.
Rotational alignment of the tibial component affects the kinematic rotation of the replaced knee during a weight-bearing condition even though using a low-restricting designed surface, and the AP axis can be a reliable reference in determining rotational alignment for the tibial component.
本研究旨在阐明全膝关节置换术后假体的旋转对线不良如何在负重状态下影响旋转运动学。
在这项对18个采用后稳定型固定平台系统置换膝关节的研究中，该系统设计限制相对较低，使用基于放射学的图像匹配技术在三维空间中对爬楼梯过程中股骨和胫骨部件之间以及股骨与胫骨之间的旋转角度进行了体内评估。通过术后CT评估部件的旋转对线。评估了爬楼梯过程中旋转对线与旋转角度之间的相关性。
胫骨部件的旋转对线与爬楼梯过程中部件之间以及骨骼之间的旋转角度显著相关。胫骨部件向内旋转的旋转对线不良导致在0°伸展时胫骨部件相对于股骨部件向内旋转的旋转不匹配，并导致胫骨（骨骼）相对于股骨（骨骼）向外旋转的旋转不匹配。胫骨部件放置靠近胫骨前后轴的膝关节在部件或骨骼之间均未显示任何旋转不匹配。
即使使用限制较低设计的表面，胫骨部件的旋转对线在负重状态下仍会影响置换膝关节的运动旋转，并且前后轴可以作为确定胫骨部件旋转对线的可靠参考。
