Teres Major Muscle, Anterior View

Description

Arising from the posterior surface of the inferior angle and adjacent lateral border of the scapula, the teres major sweeps superolaterally to its insertion on the medial lip of the intertubercular sulcus (crest of the lesser tubercle) of the humerus. From an anterior perspective, its thick tendon can be appreciated coursing anterior to the long head of the triceps brachii as the muscle wraps around the inferior border of the scapula. Lateral to it, the latissimus dorsi converges toward the floor of the intertubercular sulcus, with the two muscles forming a close functional pair at the posterior axillary fold. A clean relationship. This angle matters when teaching axillary anatomy because the teres major marks the inferior boundary of the quadrangular space and helps define the interval that transmits the circumflex scapular vessels through the triangular space. Clinically, distinguishing teres major from latissimus dorsi is useful during physical examination and operative planning for tendon transfer or reconstruction, where the teres major tendon can be mobilized near its humeral insertion while protecting the posterior circumflex humeral vessels and the axillary nerve in the adjacent quadrangular space. It is also a practical orientation for correlating anterior shoulder pain with internal rotation and adduction overuse patterns. Use this illustration in gross anatomy or kinesiology teaching to reinforce scapulohumeral muscle lines of pull, or in surgical education materials describing posterior axillary fold exposure and regional neurovascular corridors. It also suits publisher layouts discussing shoulder tendon transfers, athletic overuse injuries, or axillary space boundaries in cross-referenced atlases. Anatomical accuracy verified by SciePro's Medical Advisory Board.