has part has part characteristic of inheres in has modifier Abnormal peripheral nerve morphology by anatomical site Abnormal great auricular nerve morphology 2015-08-07T01:08:45Z Any structural anomaly of a great auricular nerve. HP:3000048 The great auricular nerve originates from the cervical plexus and ascends to the posterior inferior region of the parotid gland, where it divides into several small branches. The nerve supplies sensation for an extensive area of the face including the skin over the parotid gland and the mastoid process and the surface of the external ear. The great auricular nerve winds around the posterior aspect of the sternocleidomastoid muscle. After perforating the deep fascia, it ascends upon the sternocleidomastoid muscle beneath the platysma to the parotid gland, where it divides into an anterior and a posterior branch. The anterior branch provides sensory innervation to the skin overlying the parotid gland and communicates with the facial nerve in the substance of the gland. The posterior branch innervates the skin over the mastoid and the posterior surface of the auricle except at its upper part. UMLS:C4073256 morphology abnormal great auricular nerve