Helmig P, Søjbjerg J O, Kjaersgaard-Andersen P, Nielsen S, Ovesen J
Biomechanics Laboratory, Orthopaedic Hospital, University of Aarhus, Denmark.
Clin Orthop Relat Res. 1990 Mar(252):139-43.
The object of the present study of autopsy specimens was to evaluate distal humeral migration during abduction allowed by sequential severance of capsular and ligamentous structures stabilizing the shoulder joint. A kinesiologic testing device continuously registered distal humeral migration, abduction angle, rotation, and flexion-extension. No distally directed force was applied to the humerus except the weight of the apparatus. Significant distal migration was recorded in the entire range of abduction (0 degrees -60 degrees) after solitary severance of the coracohumeral ligament as well as the proximal part of the anterior joint capsule. Further sectioning of the proximal part of the posterior capsule did not significantly increase distal humeral migration. Maximum distal migration (25 mm) was measured at 20 degrees of abduction. Applying an internal torque to the humerus significantly prevented distal migration as long as the posterior capsule was kept intact. Clinical testing for distal humeral migration should be performed with the shoulder joint at 20 degrees of abduction and neutral rotation. Furthermore, distal humeral migration can be significantly reduced by internal rotation of the humerus when the posterior joint capsule is intact.
本研究对尸检标本的目的是，通过依次切断稳定肩关节的关节囊和韧带结构，评估外展过程中肱骨远端的移位情况。一种运动学测试装置持续记录肱骨远端的移位、外展角度、旋转以及屈伸情况。除了装置的重量外，未对肱骨施加向远端的力。在单独切断喙肱韧带以及前关节囊近端部分后，在整个外展范围（0度至60度）均记录到明显的远端移位。进一步切断后关节囊近端部分并未显著增加肱骨远端的移位。在外展20度时测量到最大远端移位（25毫米）。只要后关节囊保持完整，对肱骨施加内扭矩可显著防止远端移位。肱骨远端移位的临床测试应在肩关节外展20度且旋转中立位时进行。此外，当后关节囊完整时，肱骨内旋可显著减少肱骨远端移位。
