Teres Major Under the Skin

Description

Posterior surface anatomy of an adult male shoulder girdle is presented with the scapula and proximal humerus visible beneath translucent soft tissues, centering attention on the teres major as it courses from the inferior angle and adjacent lateral border of the scapula toward the medial lip of the intertubercular sulcus (crest of the lesser tubercle) of the humerus. Its thick muscular belly lies inferior to teres minor and posterior to the axillary interval, with the latissimus dorsi positioned more inferiorly and often blending near the humeral insertion. Overlying contours of the posterior deltoid occupy a more superolateral position, while the spine and ribs provide midline and thoracic reference. Teres major matters because it is a consistent landmark for the posterior axillary fold and a practical guide to the quadrangular and triangular spaces, where the axillary nerve and posterior circumflex humeral artery, and the radial nerve with profunda brachii artery, travel in close surgical proximity. Strain or tendinopathy at the humeral insertion can mimic latissimus dorsi pain in throwing athletes, and hypertrophy or scarring in this region can complicate posterior shoulder approaches and axillary dissections. Short. Its relationship to the scapular inferior angle also helps teach how scapulothoracic position changes the line of pull for adduction, extension, and medial rotation of the humerus. Use this artwork in gross anatomy and kinesiology modules covering the posterior shoulder and axilla, in orthopedic and sports medicine texts discussing posterior axillary fold injuries, and in surgical education materials for posterior shoulder exposure and axillary neurovascular mapping. Anatomical accuracy verified by SciePro's Medical Advisory Board.