Department of Orthopaedic Surgery, Tokyo Women's Medical University, 8-1 Kawada-cho, Shinjuku-ku, Tokyo, 162-8666, Japan.
BMC Musculoskelet Disord. 2022 Jun 13;23(1):568. doi: 10.1186/s12891-022-05526-z.
Change in the joint line convergence angle (JLCA) of the knee after high tibial osteotomy (HTO) is difficult to predict accurately. Given that any change in JLCA is intra-articular, the shape of the articular surface, including the bone morphology of the proximal tibia, may affect the alignment of the knee joint postoperatively. The purpose of this study was to investigate the relationship between the shape of the tibial plateau and postoperative alignment of the knee joint by focusing on changes in JLCA.
One hundred and nine knees that underwent HTO were retrospectively reviewed. The shape of the tibial plateau was classified based on the slope of the medial and lateral articular surfaces as depressed, flat (within 3 degrees), or convex (pagoda-like). The relationship between the shape of the tibial plateau and radiological parameters was investigated.
The shape of the tibial plateau was depressed in 38 knees, flat in 52 knees, and pagoda-like in 19 knees. There was a moderate correlation between the postoperative change in JLCA and the preoperative hip-knee-ankle angle for knees with a pagoda-shaped tibial plateau (r = 0.56) but not for the other two shapes.
These findings suggest that knees with marked varus deformity before HTO are likely to show more change in JLCA postoperatively if the tibial plateau is pagoda-shaped than if it has a depressed or flat shape. The advantage of focusing on the bone morphology of the proximal tibia is that surgeons can easily perform visual assessment using preoperative radiograph.
胫骨高位截骨术（HTO）后膝关节对线的关节线会聚角（JLCA）变化难以准确预测。鉴于 JLCA 的任何变化都是关节内的，关节表面的形状，包括胫骨近端的骨形态，可能会影响术后膝关节的对线。本研究的目的是通过关注 JLCA 的变化来研究胫骨平台形状与膝关节术后对线的关系。
回顾性分析 109 例接受 HTO 的膝关节。根据内侧和外侧关节面的斜率将胫骨平台的形状分为凹陷、平坦（<3 度）或凸面（宝塔状）。研究了胫骨平台形状与影像学参数之间的关系。
胫骨平台的形状在 38 个膝关节中为凹陷，在 52 个膝关节中为平坦，在 19 个膝关节中为凸面。对于胫骨平台呈宝塔形的膝关节，术后 JLCA 的变化与术前髋膝踝角之间存在中度相关性（r=0.56），而对于其他两种形状则没有相关性。
这些发现表明，在 HTO 之前有明显内翻畸形的膝关节，如果胫骨平台呈宝塔形，则术后 JLCA 的变化更有可能发生。关注胫骨近端骨形态的优势在于，外科医生可以使用术前 X 线片轻松进行直观评估。
