The Synkinesis between Facial Mimetic and Stapedial Muscles

Abstract

Synkinesis between facial mimetic muscles is most frequently observed in sequelae of facial palsy as compared with crocodile tears, spasms, contractures and aural symptoms. Aural symptoms, such as tinnitus, ear fullness, and hearing loss are considered to be due to abnormal associated movements between facial mimetic and stapedial muscles. We examined the incidence of the synkinesis between facial mimetic and stapedial muscles as sequelae of facial palsy.
To detect these phenomena objectively, the changes in acoustic compliance of the middle ear during voluntary contraction of mimetic muscles were measured in 31 patients who were in a post therapeutic state of peripheral facial palsy.
In total, there were 24 patients with any type of sequela. The synkinesis between facial mimetic muscles was most common and observed in 20 cases. Abnormal associated movements between facial mimetic and stapedial muscles were observed in 16 (66.6%) of the 24 sequelae cases, and in 15 (75.0%) of the 20 in the facial mimetic synkinesis cases. The incidence was higher than that previously reported.