Pain around the ear in Bell's palsy is referred pain of facial nerve origin: the role of nervi nervorum.
General somatic afferents of facial nerve innervate skin of the concha, the posterior external ear canal and a small area behind the ear. But pain around the ear that precedes or develops at the same time as Bell's palsy frequently is beyond the territory of sensory innervations of facial nerve. Cranial nerves are richly innervated by their own nerves called nervi nervorum that have nociceptive function. So, stimulation of nervi nervorum dominating facial nerve trunk can be transmitted to trigeminocervical nuclear complex and make referred pain on the craniofacial region segmentally. The reason why referred pain of facial nerve origin develops around the ear is that facial nerve and its ensheathing connective tissue are derivatives of second branchial arch which is homologous to the somites of body.
Han
Dong-Gyun
DG
Department of Neurolgy, DaeJeon HanKook Hospital, ChungCheongNam-Do, Republic of Korea. tashihan@empal.com
D020330:Bell Palsy / Q000150:complications* / Q000503:physiopathology*; D004433:Earache / Q000209:etiology* / Q000503:physiopathology*; D005154:Facial Nerve / Q000503:physiopathology*; D006801:Humans; D008959:Models, Neurological; D010146:Pain / Q000503:physiopathology*