Background: Humeral head cysts are not uncommon in individuals with rotator cuff disorders. The cysts are usually considered an indicator of rotator cuff pathologies; however, they may have different meanings in different regions.
Purpose: To determine the frequency of cysts within and adjacent to the lesser tuberosity and the relationship between these cysts and subscapularis, supraspinatus, and long head of the biceps tendon (LHBT) disorders.
Material and methods: We retrospectively reviewed 760 consecutive shoulder magnetic resonance imaging (MRI) examinations. Among these MRIs, we selected a group of patients with cysts located around the lesser tuberosity. The study population was also divided into two subgroups, patients with cysts within the lesser tuberosity and those with cysts adjacent to the lesser tuberosity. In addition to the number and size of cysts, the MRI appearance of the tendons was evaluated.
Results: Eighty-one (10.7%) patients had cysts within and/or adjacent to the lesser tuberosity, 34 (42%) patients had cysts within the lesser tuberosity, and 47 (58%) patients had cysts adjacent to it. LHBT and subscapularis tendon disorders were significantly related to more than one cyst. In a univariate analysis, cysts within the lesser tuberosity were significantly associated with LHBT and subscapularis tendon disorders; however, multivariate analyses showed that only LHBT disorders were significantly associated with cysts within the lesser tuberosity.
Conclusion: Cysts within the lesser tuberosity were less common than cysts adjacent to it. LHBT and subscapularis tendon disorders were more frequently found in patients with more than one cyst within and/or adjacent to the lesser tuberosity. In addition, cysts within the lesser tuberosity were associated with LHBT disorders.
Keywords: MRI; cysts; extremity; shoulder; tendons.
© The Foundation Acta Radiologica 2014.