Corpus: Stapedial nerve
from Latin: stapes - stirrup
1. Definition
The stapedial nerve is a branch of the facial nerve that branches off within the facial nerve canal. It travels through the petrous part of the temporal bone to the middle ear, where it innervates the stapedius muscle.
2. Background
In most people, the stapedius muscle contracts reflexively and involuntarily (stapedius reflex). However, some people are able to trigger a voluntary contraction of the stapedius muscle via the stapedius nerve.
3. Clinic
Hyperacusis can occur if the facial nerve (and thus the stapedius nerve) is damaged.