Heijens E, Kornherr P, Meister C
Gelenkzentrum Rhein-Main, Wilhelmstr.30, 65193 Wiesbaden, Germany.
Dr. Horst Schmidt Kliniken, Ludwig-Erhardt Str. 100, 65199 Wiesbaden, Germany.
Bone Joint J. 2016 May;98-B(5):628-33. doi: 10.1302/0301-620X.98B5.33394.
In patients undergoing medial opening wedge high tibial osteotomy (MOWHTO), soft tissue opening on the medial side of the knee is difficult to predict. When the load bearing axis is corrected beyond a certain point, the knee joint tilts open on the medial side. We therefore hypothesised that there is a tipping point and defined this as the coronal hypomochlion.
In this prospective study of 150 navigated MOWHTOs (144 consecutive patients), data were collected before surgery and at three months post-operatively. In order to calculate the hypomochlion, we compared the respective changes to the joint line convergence angle (JLCA) with the post-operative axis of the leg. The change to the medial proximal tibial angle accounts for only about 80% of the change to the femorotibial angle; 20% of the correction can therefore be attributed to non-osseous, soft-tissue changes.
We were able to demonstrate a linear change of JLCA in a range of 0° to 5° of valgus which started when the post-operative long-leg axis was corrected beyond 2° of valgus.
We found that the coronal hypomochlion occurs at 2° of valgus.
It is recommended to plan realignment for medial open wedge high tibial osteotomy at a maximum of 2° valgus. Cite this article: Bone Joint J 2016;98-B:628-33.
在行内侧开放楔形高位胫骨截骨术（MOWHTO）的患者中，膝关节内侧的软组织开口难以预测。当负重轴矫正超过某一点时，膝关节在内侧倾斜打开。因此，我们假设存在一个临界点，并将其定义为冠状面低力矩点。
在这项对150例导航MOWHTO（144例连续患者）的前瞻性研究中，在手术前和术后三个月收集数据。为了计算低力矩点，我们将关节线汇聚角（JLCA）的各自变化与术后腿部轴线进行了比较。胫骨近端内侧角的变化仅约占股胫角变化的80%；因此，20%的矫正可归因于非骨性的软组织变化。
我们能够证明，当术后长腿轴线矫正超过2°外翻时，JLCA在0°至5°外翻范围内呈线性变化。
我们发现冠状面低力矩点出现在2°外翻时。
建议在内侧开放楔形高位胫骨截骨术的对线调整计划中，外翻角度最大为2°。引用本文：《骨关节杂志》2016年；98-B：628-33。
