11-year-old boy with history of lupus and 6 weeks of shoulder pain. ROTATOR CUFF: The rotator cuff tendons are intact. There is inflammatory change surrounding the muscle bellies of the infraspinatus and teres minor. The supraspinatus and subscapularis appear normal.SUPRASPINATUS OUTLET: There is a minimal amount of fluid in the subacromion/subdeltoid bursa.GLENOHUMERAL JOINT AND GLENOID LABRUM: Glenohumeral joint alignment is normal and the glenoid labrum is intact. A very small amount of fluid is seen in the joint space.BICEPS TENDON: The biceps tendon is well-positioned within the bicipital groove and intact. A minimal, normal amount of fluid is seen in the biceps tendon sheath. ADDITIONAL
Inflammation of the infraspinatus and teres minor muscles without rotator cuff tear. These findings are most suggestive of myositis and, given the patient's history, likely due to lupus. Other, less likely differential considerations include dermatomyositis, polymyositis, trauma, or infection.