Sangeorzan B J, Wagner U A, Harrington R M, Tencer A F
Surgical Service, Department of Veteran's Affairs Medical Center, Seattle, Washington.
J Orthop Res. 1992 Jul;10(4):544-51. doi: 10.1002/jor.1100100409.
In this study we determined the effects of misalignment of the talar neck on the contact characteristics of the subtalar joint. Each of seven fresh cadaver lower extremities was mounted in a loading jig and a vertical load was applied, 90% of which was directed through the tibia and 10% through the fibula. The foot was allowed to displace freely in the horizontal plane so that relative rotations, known to occur in the subtalar joint, would not be prevented. Pressure-sensitive film, inserted into the posterior and anterior/middle articulations, was used to quantify changes in contact characteristics. After testing in the normal condition, the talar neck was osteotomized and stabilized with internal and external skeletal fixation. Contact characteristics were then determined in each of the following stages: anatomic realignment, or with 2-mm displacement of the talar neck either dorsally, medially, laterally, or complex (dorsal and varus) with respect to the body of the talus. Measurements showed no significant changes in overall contact area or high pressure area in the posterior facet, although four of the seven specimens demonstrated increased localization of the contact area into two discrete regions. The combined anterior/middle facet, on the other hand, was significantly unloaded by all but medial displacement of the talar neck. An extraarticular load path and/or increased loading directly on the talonavicular joint was presumed to account for the loss of load transfer in the talocalcaneal joint.
在本研究中，我们确定了距骨颈对线不良对距下关节接触特性的影响。将七个新鲜尸体下肢分别安装在加载夹具中，并施加垂直载荷，其中90%的载荷通过胫骨传导，10%通过腓骨传导。允许足部在水平面内自由位移，以防止距下关节中已知会发生的相对旋转受到阻碍。插入后关节和前/中关节的压敏膜用于量化接触特性的变化。在正常条件下进行测试后，对距骨颈进行截骨术，并采用内外部骨骼固定进行稳定。然后在以下每个阶段确定接触特性：解剖复位，或距骨颈相对于距骨体在背侧、内侧、外侧或复合（背侧和内翻）方向上有2毫米的位移。测量结果显示，后关节面的总接触面积或高压面积没有显著变化，尽管七个标本中有四个显示接触面积增加并集中在两个离散区域。另一方面，除距骨颈内侧移位外，所有其他移位均使前/中关节面的负荷显著减轻。据推测，关节外负荷路径和/或直接作用于距舟关节的负荷增加是距跟关节负荷传递损失的原因。
