Correlation of some anatomical angles of the shoulder with rotator cuff syndrome

Background: Shoulder movement occurs through the coordinated work of muscles, tendons, ligaments, and bones, primarily that affect the glenohumeral joint. Some distances and the angles between the bones forming this joint are important in shoulder pathologies. In this study, we aimed to determine the evaluation of nine different radiological parameters related to acromion and humerus in rotator cuff syndrome and control group patients. Materials and Methods: A total of 400 patients' routine clinic radiographs were retrospectively assessed, which have rotator cuff syndrome (n = 210), and control group (n = 190). We measured the critical shoulder angle (CSA), distance of glenoid-acromion (GA), distance of glenoid-humeral head (GH), acromial index, lateral acromial angle (LAA), total shoulder arthroplasty angle (TSA), reverse shoulder arthroplasty angle (RSA), Point T represents the superior border of the glenoid cavity, Point S represents the inferior border of the glenoid cavity, point R represents the intersection of the supraspinatus fossa line with the glenoid surface. RST angle, and greater tuberosity angle (GTA) angle. We determined the type of acromion. Results: We determined that the GH, TSA, RST, and GTA were significantly different between rotator cuff syndrome and control group patients. When we evaluated the acromion type, Type 2 was the most common type. Different from the literature, when we evaluated the relationship between acromion types and angles, we determined that LAA, GA, and TSA parameters were significantly different between acromion types. Conclusions: In this study, we determined the importance of measurements and angles in rotator cuff syndrome. We think that the relationship between acromion types and parameters can contribute to the literature. Moreover, we believe that our study will contribute to the literature in terms of gathering many angles that are important in shoulder pathologies in a single study.