The lower subscapular nerve, also known as the inferior subscapular nerve, is the third branch of the posterior cord of the

brachial plexus The brachial plexus is a network () of nerves formed by the anterior rami of the lower four cervical nerves and first thoracic nerve ( C5, C6, C7, C8, and T1). This plexus extends from the spinal cord, through the cervicoaxillary canal in t ...

. It innervates the inferior portion of the

subscapularis muscle The subscapularis is a large triangular muscle which fills the subscapular fossa and inserts into the lesser tubercle of the humerus and the front of the capsule of the shoulder-joint. Structure It arises from its medial two-thirds and So ...

and the teres major muscle.

Structure

The lower subscapular nerve contains

axons An axon (from Greek ἄξων ''áxōn'', axis), or nerve fiber (or nerve fibre: see spelling differences), is a long, slender projection of a nerve cell, or neuron, in vertebrates, that typically conducts electrical impulses known as action p ...

from the

ventral rami The ventral ramus (pl. ''rami'') (Latin for ''branch'') is the anterior division of a spinal nerve. The ventral rami supply the antero-lateral parts of the trunk and the limbs. They are mainly larger than the dorsal rami. Shortly after a spinal ...

of the C5 and C6 cervical

spinal nerves A spinal nerve is a mixed nerve, which carries motor, sensory, and autonomic signals between the spinal cord and the body. In the human body there are 31 pairs of spinal nerves, one on each side of the vertebral column. These are grouped into the ...

. It is the third branch of the posterior cord of the

. It gives branches to 2 muscles: *

. It usually gives 4 branches to innervate the subscapularis, and can give up to 8 branches. * teres major muscle.

Function

The lower subscapular nerve innervates the

and the teres major muscle. These muscles

medially rotate Motion, the process of movement, is described using specific anatomical terms. Motion includes movement of organs, joints, limbs, and specific sections of the body. The terminology used describes this motion according to its direction relative ...

and

adduct An adduct (from the Latin ''adductus'', "drawn toward" alternatively, a contraction of "addition product") is a product of a direct addition of two or more distinct molecules, resulting in a single reaction product containing all atoms of all co ...

the

humerus The humerus (; ) is a long bone in the arm that runs from the shoulder to the elbow. It connects the scapula and the two bones of the lower arm, the radius and ulna, and consists of three sections. The humeral upper extremity consists of a r ...

Additional images

File:Brachial plexus.svg, Brachial plexus File:Gray809.png, The right brachial plexus (infraclavicular portion) in the axillary fossa; viewed from below and in front. File:Brachial_plexus_color.svg, Brachial plexus with courses of spinal nerves shown

References

Nerves of the upper limb {{Portal bar, Anatomy