Objective: To examine the relationship between the morphological parameters of the shoulder joint and supraspinatus tendinosis. Methods: A patient group (n=44) was formed from patients diagnosed with supraspinatus tendinosis from medical records and magnetic resonance imaging (MRI) findings. A control group (n=44) was formed by randomly selecting people of similar age and gender to the patient group, who met the exclusion criteria for the patient group, and had normal rotator cuffs on MRI. Coracoacromial ligament thickness (CLT), acromial angle [(AA), delta angle], acromioglenoid angle (AGA), supraspinatus fossa (SFA) glenoid angle on the axial (SGAX) views, SFA glenoid angle on the anterior-posterior (SGAP) views, acromiohumeral distance (AHD), and coracoacromial arch angle (CAA) were measured on MRI images in both groups. Morphological differences between groups were compared using Student’s t-test. Results: Patient group had statistically significant higher CLT and lower AHD values (0.73±0.33 mm and 6.55±0.97 mm, respectively; p=0.007) than control group (1.02±0.53 mm and 7.45±1.61 mm, respectively; p=0.006). Also, there were statistically significant differences between the groups in terms of acromial angle (3.09±5.04° for patient group and 7.9±8.1° for control group; p=0.006). However, there were no statistically significant differences between the groups for AGA, SGAX, SGAP, and CAA (p>0.05). Conclusion: These findings suggest that CLT, AA, and AHD are important predisposing anatomical factors for developing supraspinatus tendinosis. [ABSTRACT FROM AUTHOR]