Teres minor muscle

The teres minor (Latin teres meaning 'rounded') is a narrow, elongated muscle of the rotator cuff.

Structure

It arises from the dorsal surface of the axillary border of the scapula for the upper two-thirds of its extent, and from two aponeurotic laminæ, one of which separates it from the infraspinatus muscle, the other from the teres major muscle.

Its fibers run obliquely upward and laterally; the upper ones end in a tendon which is inserted into the lowest of the three impressions on the greater tubercle of the humerus; the lowest fibers are inserted directly into the humerus immediately below this impression.

Relations

The tendon of this muscle passes across, and is united with, the posterior part of the capsule of the shoulder-joint.

Innervation

The muscle is innervated by the posterior branch of axillary nerve where it forms a pseudoganglion. A pseudoganglion has no nerve cells but nerve fibres are present. Damage to the fibers innervating the teres minor is clinically significant.