Neck surface electromyography as a measure of vocal hyperfunction before and after injection laryngoplasty

Objectives: The goal of this preliminary study was to determine whether neck surface electromyography (sEMG) is sensitive to possible changes in vocal hyperfunction associated with injection laryngoplasty, particularly with respect to alterations in the degree of vocal hyperfunction. Methods: Thirteen individuals undergoing office-based injection laryngoplasty for glottal phonatory insufficiency were prospectively studied with a battery of acoustic, aerodynamic, endoscopic, and anterior neck sEMG assessments before the procedure and approximately 1 week afterward. Results: Anterior neck sEMG values were not significantly reduced (p < 0.05) after the procedure; however, perceptual ratings of strain and false vocal fold compression were both significantly reduced, reflecting a decrease in vocal hyperfunction. Conclusions: The results do not support the use of anterior neck sEMG measures to assess vocal hyperfunction, and place into question the use of some other measures (estimates of anterior-posterior supraglottic compression, quantitative measures of anterior-posterior and false vocal fold supraglottic compression, and acoustic vowel rise times) that have been considered reflective of vocal hyperfunction.