Clinical outcomes after decompression of the nerve to the teres minor in patients with idiopathic isolated teres minor fatty atrophy

Background: The purpose of this manuscript is to describe what we believe to be the first series of patients surgically treated for idiopathic isolated teres minor atrophy and to present the results of surgical decompression of the nerve to the teres minor. Methods: This is a retrospective cohort of 22 patients who underwent decompression of the nerve to the teres minor for isolated teres minor atrophy. Clinical data including duration of symptoms, additional diagnoses, concurrent procedures, preoperative physical examination findings, imaging data, and preoperative visual analog scale (VAS), Simple Shoulder Test (SST), and American Shoulder and Elbow Surgeons (ASES) scores were collected from the medical record. Postoperative patient-based clinical outcome measures including VAS, SST, and ASES scores were obtained during clinical examination or by telephone interview. Results: Average length of follow-up was 26months. Nine patients had concurrent procedures performed. Preoperatively, 12 of 14 (86%) had external rotation weakness in Hornblower's position. Postoperatively, pain scores decreased an average of 4 points; ASES scores increased 31.7±20.2 points; SST scores increased 3.1±2.3 points. No external rotation weakness was noted postoperatively in any tested patient. Two patients developed adhesive capsulitis. No other complications occurred. Conclusions: Isolated compression of the nerve to the teres minor is a rare and novel clinical entity. In properly selected cases, open release of the fascial sling enveloping the nerve branches to the teres minor can provide relief of symptoms and clinical improvement.