Teres major muscle

Teres major muscle is one of the seven scapulohumeral muscles that act around the glenohumeral joint to facilitate shoulder movement.

Summary

• origin: caudal two thirds of lateral border and inferior angle of scapula
• insertion: medial border of the intertubercular groove, which is the crest of lesser tubercle of humerus
• innervation: lower subscapular nerve (C5,C6)
• arterial supply: thoracodorsal branch of the subscapular artery, posterior circumflex humeral artery
• action: medial shoulder rotation, extension and adduction

Gross anatomy

The muscle originates from the dorsal surface of the inferior angle of the scapula and inserts on the medial lip of the intertubercular groove of the humerus. It is related to the latissimus dorsi muscle which wraps around the lower border of teres major. The tendon of the teres major lies posterior to the tendon of the latissimus dorsi and there is a bursa between them.