Study on the Validity of Surface Electromyography as Assessment Tools for Facial Nerve Palsy

Objectives: The purpose of this study was to find out validity of Surface Electromyography(sEMG) compared with Nerve Conduction Study and clinical assessment scale as assessment factors for facial palsy. Methods: We investigated 50 cases of patients with peripheral facial palsy who had records of sEMG and NCS to check. Then we analyzed the correlation between sEMG and NCS that carried out around 1 week after onset. And we analyzed the correlation between sEMG and clinical assessment scales that were measured three times around 1 week, 3-4 weeks and 5-6 weeks after onset. Clinical assessment scales used in this study were House-brackmann grade, Yanagihara unweighted grading scale and Sunnybrook facial grading system. We used Pearson's correlation for statistical analysis. Results: sEMG and NCS, measured at similar times, were statistically correlated. Especially, the correlation with the forehead region was high. And sEMG and clinical assessment scale, measured at same time, were statistically correlated, especially after 5 weeks from onset. Conclusion: According to this study, sEMG is expected to be useful to assessment facial palsy.