Morphofunctional analysis of rotator cuff in subjects with glenohumeral instability

Abstract

Previously studies in shoulder instability demonstrated that morphologic changes occur in the rotator cuff, which would impair the functional ability and also shoulder stability. To the best of our knowledge, until this moment no study evaluated both morphologic and functional characteristics of rotator cuff in those patients. The aim of this study is to establish the morphologic changes of rotador cuff in patients with anterior shoulder instability and surgery indication, correlating these findings with muscular performance measured by isokinetic dynamometry. To achieve our goals, we will select 40 male subjects between 18 to 30 years, with regular participation in overhead sports, separated in two groups: 1) Surgery group (n=20): overhead athletes with surgery indication to instability correction; 2) Control group (n=20): overhead athletes without instability and matched by age, sport and time of training with surgery group. All subjects will undergo a force accuracy and steadiness test of abductors/adductors and external/internal rotators in an Isokinetic Dynamometer (Biodex Multi Joint System 3, Biodex Medical Systems Inc.) in isometric, concentric and eccentric modes. Only Surgery Group will be submitted to muscles biopsies of Supraspinatus, Infraspinatus and Subscapularis during the surgical repair of anterior instability and will be analyze with qualitative and morphometric measurements. All statistics will be perform using the statistical package SPSS for Windows (version 13.0), and a p value of <0.05 will be considered as a statistically significant difference. (AU)