The Teres Major Muscle Viewed Posteriorly in a Male

Description

Positioned on the posterior scapulohumeral region, the teres major occupies the inferolateral border of the scapula, running superolaterally from the dorsal surface of the inferior angle toward its insertion on the medial lip of the intertubercular sulcus of the humerus. Superior to it, the smaller teres minor sits along the lateral border of the scapula and blends with the posterior capsule as part of the rotator cuff, while the infraspinatus lies more superior and medial within the infraspinous fossa. Laterally, the deltoid caps the shoulder, and inferiorly the latissimus dorsi converges with teres major to form the posterior axillary fold adjacent to the axilla. Fiber direction is clear. This posterior perspective matters because teres major is frequently confused with teres minor during physical exam and in operative anatomy, yet the clinical implications differ: teres minor weakness points toward axillary nerve injury in the quadrangular space, while teres major pain often reflects overload during powerful adduction and internal rotation (rowing, climbing, swimming) or traction injuries at its humeral insertion. The relationship between teres major, latissimus dorsi, and the long head of the triceps also frames the boundaries of the triangular and quadrangular spaces, a practical map when evaluating posterior shoulder pain or planning a posterior approach to the proximal humerus. Distinguish the rotator cuff from the axillary fold. Use this asset in upper limb gross anatomy teaching to anchor scapular landmarks, in orthopedic or sports medicine publications addressing posterior shoulder strains and axillary nerve palsy, and in surgical education when orienting the posterior axillary fold for latissimus dorsi or teres major tendon transfer discussions. Anatomical accuracy verified by SciePro's Medical Advisory Board.