Teres major muscle

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"Teres major" redirects here. For the beef cut, see shoulder tender.
Teres major muscle
Teres major.PNG
Posterior view showing the relations between teres major muscle (in red) and the other muscles connecting the upper extremity to the vertebral column.
Teres major muscle back.png
Teres major muscle (in red) seen from back.
Latin Musculus teres major
Gray's p.442
Origin Posterior aspect of the inferior angle of the scapula
Insertion Medial lip of the intertubercular sulcus of the humerus
Artery Subscapular and circumflex scapular arteries
Nerve Lower subscapular nerve (segmental levels C5 and C6)
Actions Internal rotation (medial rotation) of the humerus, Protracts scapula, Depress shoulder
TA A04.6.02.011
FMA FMA:32549
Anatomical terms of muscle

The teres major muscle (Latin teres meaning 'rounded') is a muscle of the upper limb and one of seven scapulohumeral muscles. It is a thick but somewhat flattened muscle, innervated by the lower subscapular nerve (C5 and C6).

Structure[edit]

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 rotator cuff lateral rotator pair of the teres minor and infraspinatus.

The fibers of teres major insert into the medial lip of the intertubercular sulcus of the humerus.

Relations[edit]

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.

The teres major muscle is innervated by the lower subscapular nerve of the brachial plexus.

Function[edit]

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.

Additional images[edit]

See also[edit]

This article uses anatomical terminology; for an overview, see anatomical terminology.

References[edit]

This article incorporates text from a public domain edition of Gray's Anatomy.

External links[edit]