肩の挙上動作に影響を与える小円筋の非定型石灰性腱炎：症例報告

Calcific tendinitis is a common cause of shoulder pain, with the supraspinatus tendon most frequently affected. In contrast, involvement of the teres minor tendon is exceptionally rare. We report an unusual case of a 55-year-old woman experiencing persistent left shoulder pain for six months, exacerbated by overhead activities. Clinical examination revealed point tenderness over the posterolateral shoulder and restricted abduction and external rotation. Imaging identified a 1.8 cm calcification within the teres minor tendon. Given the unresponsiveness to non-operative treatments, arthroscopic removal of calcifications and teres minor tendon repair was performed, resulting in pain-free motion and a return to overhead activities. Postoperative MRI confirmed tendon integrity and absence of calcification recurrence. This case highlights the importance of considering atypical presentations of calcific tendinitis, particularly in the context of isolated posterior shoulder pain. Recognition of this rare tendon involvement is essential to avoid misdiagnosis and to guide appropriate surgical planning when conservative measures fail. Furthermore, this report demonstrates that arthroscopic intervention, including targeted debridement and teres minor tendon repair, can yield excellent clinical outcomes even with unusual presentation. Raising awareness of such rare cases may support earlier diagnosis and tailored treatment, ultimately improving patient outcomes. LEVEL OF EVIDENCE: Level V, Case report.