The Contribution of Surface Electromyographic Assessment for Defining the Stage of Peripheral Facial Paralysis: Flaccid or Sequelae Stage

Abstract

Introduction Surface electromyographic activity may not be symmetric, even in subjects with no facial paralysis history. Objective To evaluate the contribution of the index of electromyographic (IEMG) activity in the identification of the two extremes of the facial paralysis course. Methods Thirty-four subjects with unilateral peripheral facial paralysis were selected. A control group was composed of volunteers without a history of facial paralysis. The electromyographic assessment of the facial muscle was performed by placing surface electrodes during movements of the forehead, eyes and lips using MIOTEC equipment, such as the MIOTOOL (Miotec, Porto Alegre, Brazil) software. The electromyographic activity was also recorded in other channels during the primary activity to identify the presence of synkinesis. The statistical analysis was performed using the Statistical Package for Social Sciences for Macintosh (SPSS Inc, Chicago, IL, USA). The IEMG activity was obtained from the division of the electromyographic activity root mean square (RMS) values on both sides. Results There was a statistically significant difference among the groups in all the analyzed indexes. The ocular-oral synkinesis in all patients must be correctly identified (with 100% sensitivity and specificity) using an IEMG activity of 1.62 as a cutoff point. The oral-ocular synkinesis must be correctly identified (93.3% sensitivity and 95.9% specificity) using the IEMG activity of 1.79 as a cutoff point. Conclusion The IEMG activity is below the normal scores in patients in the flaccid stage, whereas patients in the sequelae stage can either show normal values or values above or below the normal scores. The IEMG activity was shown to have high sensitivity and specificity in the identification of synkinesis.

Electromyography of Extrinsic and Intrinsic Ear Muscles in Healthy Probands and Patients with Unilateral Postparalytic Facial Synkinesis

“…Needle electromyography is the standard method to objectively confirm facial synkinesis—that is, the abnormal involuntary facial movement that occurs with voluntary movement of a different facial muscle group [ 3 ]. Surface EMG also makes it possible to prove facial synkinesis [ 17 ]. The present study is the first to systematically show that postparalytic synkinesis also includes the extrinsic and intrinsic ear muscles.…”

Learning from EMG: semi-automated grading of facial nerve function

“…This might be useful in case of synkinesis. Bernardes et al [ 26 ] showed that there is significant synkinesis even in healthy patients between both halves. This suggests a need for an objective but still comparable parameter which can evaluate the healthy and affected half of the face separately.…”

The impact of occlusal plane rehabilitation on the face of a patient with traumatic peripheral facial paralysis by Timpanic jugular tumor – case report

“…It is performed with individuals sitting in a chair with a vertical backrest and with their feet supported on a rubber mat. The skin must be cleaned with 70 % alcohol to obtain better attachment of the electrodes [11].…”