Yeh Ming-Long, Lintner David, Luo Zong-Ping
Department of Orthopedic Surgery, Baylor College of Medicine, 6550 Fannin, Suite 451, Houston, TX 77030, USA.
Am J Sports Med. 2005 Mar;33(3):395-401. doi: 10.1177/0363546504268404.
Superior labrum anterior posterior lesions are common among athletes participating in overhead throwing sports. One described mechanism of injury is application of high local stress via repetitive loading of the long head of the biceps tendon attached to the superior labrum; however, the stress environment within the labrum has not been investigated to date.
Biceps origin locations and throwing phases determine the stress distributions causing lesions of the superior labrum within the labrum itself.
Descriptive laboratory study.
Three-dimensional finite element models of the labrum glenoid complex with anterior, central, and posterior biceps origins were developed at 4 orientations to simulate the phases of pitching: early cocking, late cocking, acceleration, and deceleration.
The stress magnitudes at the labrum glenoid interface for the deceleration phase were highest for all biceps origins. Anatomical variations of the biceps insertion affected the stress only during the deceleration phase. Both the biceps origin and throwing phase influenced the location of high stress.
Deceleration could be the throwing phase that causes tearing at the superior labrum. This finding provides further understanding for localizing the possible initiation of superior labrum anterior posterior lesions.
上盂唇前后部损伤在从事过顶投掷运动的运动员中很常见。一种描述的损伤机制是通过反复加载附着于上盂唇的肱二头肌长头施加高局部应力；然而，迄今为止尚未对上盂唇内的应力环境进行研究。
肱二头肌起点位置和投掷阶段决定了上盂唇内导致上盂唇损伤的应力分布。
描述性实验室研究。
开发了具有前、中、后肱二头肌起点的盂唇-关节盂复合体的三维有限元模型，以4种取向模拟投球阶段：早期引臂、晚期引臂、加速和减速。
所有肱二头肌起点在减速阶段的盂唇-关节盂界面处的应力大小最高。肱二头肌止点的解剖变异仅在减速阶段影响应力。肱二头肌起点和投掷阶段均影响高应力的位置。
减速可能是导致上盂唇撕裂的投掷阶段。这一发现为定位上盂唇前后部损伤的可能起始部位提供了进一步的认识。
