The great auricular nerve is a sensory neck of the head and neck. It is the largest ascending branch of the cervical plexus.
It supplies sensation to the skin overlying the external ear, mastoid process, and parotid gland.
Course
The great auricular nerve arises from the ventral rami of the C2 and C3 spinal roots within the cervical plexus.
It emerges approximately halfway along the posterior border of the sternocleidomastoid muscle at Erb’s point. It then ascends vertically across the muscle, accompanied by the external jugular vein.
When it reaches the inferior pole of the parotid gland, the great auricular nerve terminates by dividing into anterior and posterior branches.
Fig 1 – Course of the great auricular nerve after arising from the cervical plexus.
Supply
The great auricular nerve supplies sensation via its two terminal branches:
- Anterior branch (facial branch) – supplies the skin overlying the parotid glands.
- Posterior branch (mastoid branch) – supplies the skin overlying the mastoid process and the posterior aspect of the external ear.
