Great auricular nerve

Origin and course

The great auricular nerve is the largest ascending branch of cervical plexus, arising from the anterior rami of spinal nerves C2 and C3. The nerve arises just behind the middle portion of the sternocleidomastoid muscle and shortly thereafter curves around its posterior border and emerges on the muscle’s anterior surface. Here, the great auricular nerve perforates the deep cervical fascia and takes an ascending course, passing under the platysma muscle along the external jugular vein. As it reaches the parotid gland, the great auricular nerve divides into its terminal branches.

The Erb’s point, or punctum nervosum, is the site where all the cutaneous branches of the cervical plexus converge, pierce the deep cervical fascia and become superficial. Aside from the great auricular nerve, these branches also include lesser occipital, transverse cervical and supraclavicular.

The nervous system is a nightmare for many. Try out nervous system quizzes and diagrams and soon you will see there’s nothing to be afraid of!

Branches and innervation

The great auricular nerve gives off two terminal branches:

• The anterior branch, also called the facial branch, which innervates the skin over the parotid gland. This branch immerses into the substance of the parotid gland, where it establishes a connection with the facial nerve.
• The posterior branch, also called the mastoid branch, which supplies the skin over the mastoid process and the posterior surface of the auricle. This branch gives off a small lateral filament, which supplies the lobule and concha. Along its course, the posterior branch communicates with the lesser occipital nerve, the auricular branch of vagus nerve (CN X) and the auricular branch of posterior auricular nerve.

Learn more about the great auricular nerve here.