Department of Orthopaedic Surgery, Kyushu University, Maidashi Higashi-ku, Fukuoka City, Japan.
J Orthop Res. 2011 Jun;29(6):919-24. doi: 10.1002/jor.21335. Epub 2011 Jan 21.
A disadvantage to using extramedullary alignment guides of the tibia for total knee arthroplasty (TKA) is difficulty in correctly identifying the ankle center. The anterior border of the tibia is easily palpable, as it is not covered by muscles and its shape is convex anteriorly. We hypothesized that appropriate points exist along the anterior border that can be used as landmarks for extramedullary guides. Prior to TKA, computed tomographic images of the entire tibia were obtained from 101 osteoarthritic knees with varus deformities. The relationship between the lines connecting two points on the anterior border and the mechanical axis was evaluated using 3D imaging software. The mean angles between each of 10 determined axes and the mechanical axis varied from 3.2° varus to 2.1° valgus in the coronal plane. In the sagittal plane, all axes referencing the anterior border of the tibia showed anterior inclination to the mechanical axis. The line connecting the medial one-third of the patellar tendon attachment and the distal one-fourth of the anterior border, however, was highly consistent and parallel to the mechanical axis in the coronal plane. This axis can be effectively used as a landmark for extramedullary guides during TKA.
使用胫骨的髓外定位导板进行全膝关节置换术（TKA）的一个缺点是难以正确确定踝关节中心。胫骨的前缘很容易触及，因为它没有被肌肉覆盖，并且其形状是向前凸的。我们假设胫骨前缘存在合适的点，可以作为髓外导板的标志。在 TKA 之前，从 101 例有内翻畸形的骨关节炎膝关节中获得了整个胫骨的计算机断层扫描图像。使用三维成像软件评估了连接胫骨前缘两点的线与机械轴之间的关系。在冠状面，10 个确定轴中的每个轴与机械轴之间的平均角度从 3.2°的内翻到 2.1°的外翻。在矢状面，参考胫骨前缘的所有轴都向机械轴的前方倾斜。然而，连接髌腱附着的内侧三分之一和前缘的远端四分之一的线在冠状面高度一致且与机械轴平行。该轴可有效地用作 TKA 期间髓外导板的标志。
