Teres Minor Under the Skin

Description

Posteriorly, the scapulae sit lateral to the thoracic vertebrae and ribs, with the proximal humeri aligned at the glenohumeral joints. Along the dorsal surface of each scapula, the infraspinous fossa is occupied by infraspinatus, while teres minor runs immediately inferior to it at the lateral border, coursing superolaterally toward the greater tubercle of the humerus. Near the posterolateral shoulder, teres minor lies superior to teres major and deep to the posterior deltoid as it approaches the quadrangular space adjacent to the surgical neck. Small, but specific. Teres minor is the rotator cuff muscle most tied to the axillary nerve, and this posterior perspective makes that relationship easier to teach even when the nerve itself is not drawn. In traumatic anterior shoulder dislocation or proximal humeral fractures at the surgical neck, axillary nerve injury can denervate teres minor, producing disproportionate loss of external rotation strength with the arm in abduction and visible posterior shoulder contour change. The same anatomy matters in the posterior approach to the shoulder and in reverse total shoulder arthroplasty planning, where fatty infiltration or atrophy of teres minor can predict weaker postoperative external rotation. Use this artwork for rotator cuff modules in gross anatomy and kinesiology courses, for orthopedic and sports medicine texts discussing external rotation deficits, and for patient education sheets explaining posterior shoulder pain patterns and dislocation-associated nerve injury. Anatomical accuracy verified by SciePro's Medical Advisory Board.