Cervical Plexus (Left)

Description

The cervical plexus is made up of the anterior rami of upper four cervical nerves (C1-C4). The anterior rami are interconnected in the form of neuronal loops, which give off superficial and deep branches to various structures.

The superficial cutaneous branches can be seen in the posterior triangle and include the:

—lesser occipital nerve;

—great auricular nerve;

—transverse cervical nerve;

—supraclavicular nerve.

The deep branches of the cervical plexus innervate several groups of muscles including prevertebral and lateral vertebral muscles. They include the:

—phrenic nerve; —ansa cervicalis;

—muscular branches.

Communicating branches emerge from the loop between the first and second cervical nerves and connect with the sympathetic trunk, as well as the vagus and hypoglossal nerves. Others arise from second, third, and fourth cervical nerves and connect with spinal accessory nerve.

Each anterior ramus receives a gray communicating branch (gray ramus communicans containing postganglionic sympathetic fibers) from the superior cervical sympathetic ganglion.