The Probert Encyclopaedia of Medicine

TERES MAJOR

The teres major is a short and thick, somewhat flattened muscle that extends from the scapula to the humerus. It originates from the inferior angle and lower portion of the scapula and inserts in the intertubercular groove of the humerus. The teres major is innervated by the fifth and sixth cervical nerves and supplied by the dorsal subscapular artery which branches from the subscapular artery. This muscle creates part of the posterior wall of the armpit and helps adduct the arm. It also rotates the arm medially behind the back. The teres major tenses when the arm lies next to the body. When the arm is extended the teres major is stretched, becoming elongated and thinner.
Research Teres Major