The great auricular nerve originates from the cervical plexus

Cervical plexus

The cervical plexus is a plexus of the ventral rami of the first four cervical spinal nerves which are located from C1 to C4 cervical segment in the neck. They are located laterally to the transverse processes between prevertebral muscles from the medial side and vertebral from lateral side...

, composed of branches of spinal nerve

Spinal nerve

The term spinal nerve generally refers to a mixed spinal nerve, which carries motor, sensory, and autonomic signals between the spinal cord and the body...

s C2 and C3. It provides sensory innervation for the skin over parotid gland

Parotid gland

The paired parotid glands are the largest of the salivary glands. They are each found wrapped around the mandibular ramus, and secrete saliva through Stensen's ducts into the oral cavity, to facilitate mastication and swallowing and to begin the digestion of starches.-Location:The parotid glands...

 and mastoid process, and both surfaces of the outer ear

Outer ear

The outer ear is the external portion of the ear, which consists of the pinna, concha, and external auditory meatus. It gathers sound energy and focuses it on the eardrum . One consequence of the configuration of the external ear is to selectively boost the sound pressure 30- to 100-fold for...

.

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 Auriculotemporal nerve

Auriculotemporal nerve

The auriculotemporal nerve is a branch of the mandibular nerve that runs with the superficial temporal artery and vein, and provides sensory innervation to various regions on the side of the head.-Origin:...

, which is the less influential of the two.

Path

It is 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

Parotid gland

The paired parotid glands are the largest of the salivary glands. They are each found wrapped around the mandibular ramus, and secrete saliva through Stensen's ducts into the oral cavity, to facilitate mastication and swallowing and to begin the digestion of starches.-Location:The parotid glands...

, 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
  Parotid gland
  The paired parotid glands are the largest of the salivary glands. They are each found wrapped around the mandibular ramus, and secrete saliva through Stensen's ducts into the oral cavity, to facilitate mastication and swallowing and to begin the digestion of starches.-Location:The parotid glands...
  
  , and communicates in the substance of the gland with the facial nerve
  Facial nerve
  The facial nerve is the seventh of twelve paired cranial nerves. It emerges from the brainstem between the pons and the medulla, and controls the muscles of facial expression, and functions in the conveyance of taste sensations from the anterior two-thirds of the tongue and oral cavity...
  
  .

• The posterior branch (ramus posterior; mastoid branch) supplies the skin over the mastoid process
  Mastoid process
  The mastoid process is a conical prominence projecting from the undersurface of the mastoid portion of the temporal bone. It is located just behind the external acoustic meatus, and lateral to the styloid process...
  
   and on the back of the auricula
  Ear
  The ear is the organ that detects sound. It not only receives sound, but also aids in balance and body position. The ear is part of the auditory system....
  
  , 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
  Concha
  Concha can refer to:* The bowl-shaped part of the pinna nearest the ear canal* Concha or Concho, a round decorative piece of metal seen on a western saddle and other horse equipment descended from the Spanish tradition....
  
  . The posterior branch communicates with the smaller occipital, the auricular branch of the vagus, and the posterior auricular branch of the facial.

External links

• Diagram at aapmr.org - "Diagram of the cervical plexus."