The aim of this study was to investigate the impact of the morphometric association between the glenoid fossa and the humeral head on rotator cuff pathology.

Shoulder MRI examinations performed for any cause in study centers between August 2008 and August 2009 were retrospectively evaluated. Shoulder MRI exams having rotator cuff pathology, such as trauma, degeneration, and acromion Type 2, 3 and 4 were excluded. The study included 62 shoulder exams with rotator cuff pathology having Type 1 acromion morphology and 60 shoulder exams without rotator cuff pathology (control group). Glenoid anteroposterior distance and the humeral head diameter in axial images, humeral head diameter and glenoid articular surface diameter in coronal images and their ratios were measured in both groups. Subacromial distance was measured using sagittal images. The rotator cuff was evaluated in fat-suppressed T2-weighted and proton density-weighted images.

The difference between subacromial distances in the rotator cuff pathology group (8.94±1.43 mm) and control group (10.96±1.62 mm) was statistically significant (p<0.001). There was no statistical significance between the two groups in humeral head diameter, glenoid articular surface diameter, glenoid anteroposterior distance and their ratios (p>0.05).

There is no association between the humeral head and the glenoid articular surface which can result in rotator cuff pathology. The glenohumeral joint was determined as a compatible joint morphometrically. Therefore, if they cannot be explained by an extrinsic cause, pathologies related to the rotator cuff itself should be investigated in subjects with rotator cuff pathology