The teres major muscle
is a muscle of the upper limb
and one of six scapulohumeral muscles. It is a thick but somewhat flattened muscle, innervated by the lower subscapular nerve
Origin and insertion
It arises from the oval area on the dorsal surface of the inferior angle of the scapula
, and from the fibrous septa
interposed between this muscle and the rotor cuff
lateral rotator pair of the teres minor
The fibers of teres major insert into the medial lip of the bicipital groove of the humerus
The tendon, at its insertion, lies behind that of the latissimus dorsi
, from which it is separated by a bursa
, the two tendons being, however, united along their lower borders for a short distance.
Together with teres minor muscle
, teres major muscle forms the axillary space
, through which several important arteries and veins pass. Teres major is not
part of the rotator cuff of the shoulder, but it does combine with the deltoideus
to make the six scapulohumeral muscles.
The teres major muscle is innervated by the lower subscapular nerve of the brachial plexus.
The teres major is a medial rotator and adductor of the humerus and assists the latissimus dorsi in drawing the previously raised humerus downward and backward (extension, but not hyper extension). It also helps stabilize the humeral head in the glenoid cavity
Image:Gray411.png|Deep muscles of the chest and front of the arm, with the boundaries of......