上肢过顶投掷类运动中继发性喙突下撞击症的机制探讨——功能解剖和生物力学研究

目的:探讨上肢过顶运动中发生继发性喙突下撞击症的机制和特点,为临床诊疗提供依据。方法:16具成人尸体32例肩关节标本上,在肩胛下肌离断前后,观察上肢过顶运动中肩袖间隙与喙突之间的动态关系;自制生物力学测定仪检测肩外展90°位外旋活动度的变化;以压敏片检测肩外展90°位最大程度外旋时肩袖间隙与喙突间接触面积和压力的改变。结果:(1)肩外展位外旋时,肱骨头有向前方移位的趋势,肩胛下肌离断后肱骨头前移更加明显;(2)肩外展90°位的最大外旋活动度,在肩胛下肌离断后明显增大;(3)肩外展90°位最大程度外旋时肩袖间隙与喙突接触面积和压力,在肩胛下肌离断后明显增大。结论:(1)肩胛下肌损伤后导致肩关节前方不稳定,肩外展外旋时肱骨头前移;(2)肩胛下肌损伤可能导致肩外展外旋时肱骨头与喙突的继发性撞击。

Mechanism of Secondary Subcoracoid Impingement in Overhead Throwing Motion——A Functional Anatomy and Biomechanics Study

Objective To study the mechanism and characteristics of subcoracoid impingement in the overhead throwing motion.Methods On the 32 shoulders form 16 cadavers,the dynamic relation of rotator interval to the coracoid with or without intact subscapularis was observed.When the shoulder externally rotated maximally in the position of 90° abduction,the maximal external rotation of the shoulder was evaluated and the contact area and pressure between rotator interval and coracoid were tested before and after the subscapularis dissection.Results (1) The humeral head had a tendency of anterior translation,which was more significant after the dissection of subscapularis;(2) The degree of shoulder external rotation in the position of 90° abduction increased following dissecting the subscapularis;(3) The contact area and pressure between rotator interval and coracoid increased after dissection of the subscapularis. Conclusion (1) The humeral head displaced anteriorly when the shoulder externally rotated and abducted as a result of subscapularis injury;(2) Subscapularis injury resulted in subcoracoid impingement between humeral head and coracoid in the position of external rotation and abduction of the shoulder.