Anterior Rami of Cervical Nerves (Left)

Description

The anterior (ventral) rami of the cervical nerves arise from the first to eighth cervical nerves (C1-C8). They are one of the two terminal branches of these spinal nerves, the other being the posterior (dorsal) rami.

The anterior rami of the first four cervical nerves (C1—C4) contribute to the formation of the cervical plexus, while the anterior rami of the latter four cervical nerves (C5—C8) join with the anterior ramus of the first thoracic nerve to form the brachial plexus.

As part of the cervical plexus, the C1—C4 anterior rami are interconnected in the form of neuronal loops and give off branches to various structures. These branches include the superficial cutaneous, deep muscular, and communicating branches.—The superficial cutaneous branches can be seen in the posterior triangle beneath the inferior (posterior) border of the sternocleidomastoid muscle. Its branches include the lesser occipital, great auricular, transverse cervical, and supraclavicular nerves.—The deep muscular branches have many sub-branches, such as the phrenic nerve, and innervate several groups of muscles including prevertebral and lateral vertebral muscles. They also contribute to the superior and inferior roots of the ansa cervicalis.

As part of the brachial plexus, the C5—C8 anterior rami contribute to the formation of trunks, divisions, cords, and multiple branches. These provide somatic motor and sensory innervation to the upper limb.

The anterior rami of the cervical nerves receive gray communicating branches (gray rami communicantes containing postganglionic sympathetic fibers) from the superior cervical sympathetic ganglion.