Predictors of Facial Synkinesis Severity

Abstract

Background: There is a lack of studies exploring factors that influence synkinesis severity. This study aimed to identify factors that may contribute to variations in severity of facial synkinesis.

Methods: The records of patients with a diagnosis of facial synkinesis presenting between 2009 and 2024 were reviewed. The synkinesis score of the eFACE Facial Nerve Clinician-Graded Scale was analyzed for associations with patient characteristics and facial palsy history using univariable and multivariable analyses.

Results: A total of 249 synkinesis patients were included in the study. The cause of facial palsy was infectious or idiopathic in 185 patients (74%), tumor resection in 40 patients (16%), trauma in 17 patients (7%), and compression of the facial nerve by a benign tumor in 7 patients (3%). Factors independently associated with more severe synkinesis scores included age of facial palsy onset older than 50 years (-7.4; 95% CI, -10.9 to -3.9; P < 0.001), diabetes (-8.6; 95% CI, -14.9 to -2.3; P = 0.007), smoking (-4.9; 95% CI, -8.0 to -1.8; P = 0.003), and intratemporal facial nerve injury (-19.4; 95% CI, -27.8 to -10.8; P < 0.001). Other variables, including sex, race, hypertension, and cause, were not found to be independently associated with synkinesis severity.

Conclusions: Older age at facial palsy onset, diabetes, smoking, and intratemporal facial nerve injury were found to be independently associated with more severe synkinesis. These findings are novel and may aid in prognostication and treatment selection.

Cliincal question/level of evidence: Risk, III.