Nerve to the stapedius

The stapedius nerve ( " stirrup nerve" ) is a branch of the facial nerve ( VII cranial nerve), the motor nerve fibers to the stapedius muscle ( stapedius ) leads in the middle ear.

The stapedius nerve originates in the descending portion of the facial canal ( facial nerve canal ) in the temporal bone and enters the eminence pyramidalis and then into the stapedius muscle. He is the only somatomotor branch of the facial nerve, which originates within the facial canal. The nerve is the efferent limb of the stapedius reflex, and responds only in the context of this reflex, for example, on large noise.

An increased sensitivity to sound ( hyperacusis ) may occur in a facial nerve damage and thus of the stapedius nerve.