Role of the shoulder muscles in controlling the glenohumeral joint and prevention of subacromial impingement in overhead activities: A meta-study.

摘要

Shoulder pain is one of the most common orthopaedic problems among individuals, and especially athletes who engage in repetitive overhead activities. Shoulder impingement syndrome is a common disorder directly related to the unique anatomy, mobility, and biomechanics of the shoulder girdle complex. This is a condition that results from repetitive microtrauma to the structures within the subacromial space, primarily the tendons of the supraspinatus and the long head of the biceps, and the subacromial bursa (Corso, G. 1995. Impingement relief test: An adjunctive procedure to traditional assessment of shoulder impingement syndrome. Journal of Orthopaedic and Sports Physical Therapy, 22(5), 183--192). Glenohumeral joint articulation is dependent upon the delicate balance of muscles, tendons, and ligaments that control the joint's stability. One of the leading causes of subacromial impingement is the weakness and imbalanced parascapular muscles that control the integrity of the glenohumeral joint. Pain and dysfunction due to excessive overhead use or abnormal positioning of the shoulder during overhead type activities such as pitching, swimming stroke, spiking or serving a volleyball, serving a tennis ball, etc., can contribute to the subacromial impingement.; The purpose of this study was to determine, through a meta-study procedure, the role that the various shoulder muscles play in stabilizing the glenohumeral joint and its articulation during overhead activities in order to avoid subacromial impingement. Twenty-four studies met the inclusion criteria requirements. Of the twenty-four studies regarding the overhead activities, three were done on golf, six were done on pitching and throwing, twelve were done on swimming (freestyle, butterfly, breaststroke, and backstroke), one was done on volleyball, one was done on tennis, and one was done on overhead motion using Moire Topographic Analysis. All twenty-four studies were published research papers with the publication dates ranging from 1981 to 1998. Based on the findings of this meta-study, it appears that some of the shoulder muscles which play crucial roles in the stability of the glenohumeral joint are: serratus anterior, rhomboids, infraspinatus, teres minor, subscapularis, latissimus dorsi, pectoralis major, and anterior deltoid. The collective action of some of these muscles is partially responsible for the protraction and adduction of the scapula along with the external rotation of the humerus, which will provide a wider subacromial space during the superior migration of the humeral head when the arm is in overhead position.