Great auricular nerve

The great auricular nerve originates from the cervical plexus, composed of branches of spinal nerves C2 and C3. It provides sensory innervation for the skin over parotid gland and mastoid process, and both surfaces of the outer ear. Pain resulting from parotitis is caused by an impingement on the great auricular nerve.
Path.
It is the largest of the ascending branches of the cervical plexus. It arises from the second and third cervical nerves, winds around the posterior border of the sternocleidomastoideus, and, after perforating the deep fascia, ascends upon that muscle beneath the platysma to the parotid gland, where it divides into an anterior and a posterior branch.