Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan.
Clin Orthop Relat Res. 2012 Oct;470(10):2746-55. doi: 10.1007/s11999-012-2325-4. Epub 2012 Apr 13.
Forearm kinematics and interosseous membrane function in chronic radial head dislocations sustained in childhood are unknown. Several procedures have been performed to reduce the radial head on the basis of static preoperative assessment in only one forearm position, but clinical results are not always favorable.
QUESTIONS/PURPOSES: We investigated the in vivo three-dimensional (3D) kinematics and length changes of interosseous membrane ligaments during forearm rotation in chronic radial head dislocations using 3D CT registration techniques.
We examined 10 patients with chronic radial head dislocations (seven Type 1 and three Type 4 Monteggia lesions). To quantify kinematics, the axis of rotation (AOR) and radial head motion were investigated using computer bone models constructed from CT data placing the forearm in three positions. We also created six interosseous membrane ligaments and calculated their 3D lengths during forearm rotation.
In Type 1 lesions, the AOR was located 2.4 mm from the center of the radial head (COR). The COR translated 2.8 mm sagittally and 3.4 mm coronally. Three interosseous membrane ligaments showed little change in length. In Type 4 lesions, the AOR was located 6.2 mm from the COR. The COR translated 10.2 mm sagittally and 4.7 mm coronally. No ligament showed an isometric pattern.
In Type 1 lesions, the radial head showed relatively stable motion in the dislocated position and the isometricity of the interosseous membrane remained, which supports the concept of ulnar osteotomy. Conversely, the radial head was unstable and the normal interosseous membrane ligament tautness pattern was disrupted in Type 4 lesions.
Level IV, diagnostic study. See Guidelines for Authors for a complete description of levels of evidence.
儿童期慢性桡骨头脱位的前臂运动学和骨间膜功能尚不清楚。已经进行了几种手术来降低桡骨头的位置，但基于单一前臂位置的静态术前评估，临床结果并不总是令人满意。
问题/目的：我们使用三维 CT 配准技术研究了慢性桡骨头脱位患者前臂旋转过程中骨间膜韧带的三维（3D）运动学和长度变化。
我们检查了 10 例慢性桡骨头脱位患者（7 例 1 型和 3 例 4 型孟氏骨折）。为了定量分析运动学，我们使用从 CT 数据构建的计算机骨骼模型，将前臂置于三个位置，研究了旋转轴（AOR）和桡骨头运动。我们还创建了六个骨间膜韧带，并计算了它们在前臂旋转过程中的 3D 长度。
在 1 型病变中，AOR 位于桡骨头中心（COR）的 2.4 毫米处。COR 矢状位平移 2.8 毫米，冠状位平移 3.4 毫米。三条骨间膜韧带长度变化不大。在 4 型病变中，AOR 位于 COR 6.2 毫米处。COR 矢状位平移 10.2 毫米，冠状位平移 4.7 毫米。没有韧带表现出等长模式。
在 1 型病变中，桡骨头在脱位位置表现出相对稳定的运动，骨间膜的等长性保持不变，这支持了尺骨截骨的概念。相反，在 4 型病变中，桡骨头不稳定，正常的骨间膜韧带紧张模式被破坏。
IV 级，诊断研究。有关证据水平的完整描述，请参见作者指南。
