Association of Supraspinatus Tear Type and Localisation Between Humeral Head Bone Cyst

Objective: This study aims to comprehensively explore the association between different types and locations of supraspinatus tendon tears and the presence of humeral head bone cysts. Specifically, the study seeks to investigate how the location and grade of supraspinatus tears, as classified by the Elmann system, correlate with the occurrence, size, and distribution of humeral cysts. Additionally, the study examines the relationship between tear dimensions (measured anteroposteriorly), the presence of joint and subacromial fluid, and the anatomical localization of the tears (footprint, critical zone, musculotendinous junction, or both). By evaluating a large cohort of shoulder MRI scans, this research aims to provide deeper insights into the clinical and diagnostic implications of supraspinatus tear characteristics in relation to cyst formation in the humeral head. Material and Methods: 350 shoulder MRIs taken in our radiology department between June 2023 and December 2023 were retrospectively evaluated by two different radiologists. The total number of patients included in the study is 290. MRI examinations were performed with a dedicated shoulder coil on a 1.5 T system MRI in the supine position of patients as the arm lying beside the body in neutral rotation. Supraspinatus tears were evaluated according to location as footprint, critical zone, both footprint and critical zone and musculotendinous junction location. Supraspinatus tear diameters were measured anteroposteriorly on sagittal images. The tear diameters were measured and their grades were determined according to the Elmann classification Results: A significant relationship was found between the location of the supraspinatus tear and the presence of a humeral cyst (P<0.05). A significant relationship was found between the type of supraspinatus tear and the presence of cysts on the humeral head (P:0.04). There is a significant relationship between the type and diameter of the tear and the presence of joint fluid. There is a significant relationship between the tear location and subacromial fluid (P: 0.01). Conclusion: This study demonstrates a significant association between supraspinatus tear types, particularly tear location, and the presence of humeral head cysts. The findings highlight that specific tear localizations, such as those in the critical zone and musculotendinous junction, exhibit a stronger correlation with cyst formation. Although no significant relationship was observed between tear diameter and cyst presence, the results underscore the importance of assessing tear characteristics to better understand cyst formation mechanisms in the humeral head. These insights may improve diagnostic accuracy and inform treatment decisions in patients with rotator cuff pathologies.