Decompression of the axillary nerve branch innervating the teres minor muscle. Report of two cases

Abstract

Introduction: Entrapment neuropathy of the axillary nerve branch innervating the teres minor muscle is a rare condition; however, the intensity of the symptoms considerably affects the quality of life of these patients.

Cases presentation: A 59-year-old woman and a 44-year-old man visited the orthopedics and trauma service of a health institution specialized in orthopedics, trauma, and sports injuries located in Barranquilla (Colombia) due to chronic (more than one year) and intense pain (visual analog scale: 8/10) in the right shoulder (dominant limb in both cases) refractory to previous treatments with oral medications and physical therapy. Neither patient had a history of trauma or surgery to the shoulder. On physical examination, both patients had positive hornblower's sign, external rotation strength in abduction at 45° of 3/5, pain in the quadrangular space, and positive Jobe test. A non-contrast MRI showed muscle atrophy and fatty infiltration of the teres minor (grade 2 in the Goutallier classification), so they were diagnosed with entrapment neuropathy of the axillary nerve branch innervating the teres minor. The patients underwent a one-stage surgical procedure involving two phases (shoulder arthroscopy and open neurolysis of the axillary nerve branch innervating the teres minor, respectively), achieving improvement in terms of function and pain up to 4 months of follow-up.

Conclusion: The surgical procedure described here allowed achieving satisfactory outcomes in both patients in terms of pain and function, thus improving their quality of life considerably.