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.

Terminology
Although this nerve is frequently referred to as the "greater" auricular nerve, this is not the proper nomenclature since there is no "lesser" auricular nerve. Great refers to the distinction between it and the posterior auricular nerve, which is the less influential of the two.

Path
It the largest of the ascending branches. 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.

Branches

 * The anterior branch (ramus anterior; facial branch) is distributed to the skin of the face over the parotid gland, and communicates in the substance of the gland with the facial nerve.


 * The posterior branch (ramus posterior; mastoid branch) supplies the skin over the mastoid process and on the back of the auricula, except at its upper part; a filament pierces the auricula to reach its lateral surface, where it is distributed to the lobule and lower part of the concha. The posterior branch communicates with the smaller occipital, the auricular branch of the vagus, and the posterior auricular branch of the facial.