Surface Electrical Stimulation for Facial Paralysis Is not Harmful.

Introduction: Does electrical stimulation (ES) of denervated muscles delay or prevent reinnervation, or increase synkinesis? This retrospective study evaluated the outcome with and without ES of patients with acutely denervated facial muscles. Methods: The effect of ES was analyzed in two experiments: In 39 patients (6 with home-based ES, median 17.5 months) undergoing facial nerve reconstruction surgery (FNRS). Time to recovery of volitional movements was analyzed. The second experiment involved 13 patients (7 with ES, median 19 months) during spontaneous reinnervation. Sunnybrook and eFACE scoring provided functional outcome measures. Results: No difference in time of reinnervation after FNRS was found between the patients with and without ES (median (IQR) 4.5(3.0, 5.25) vs. 5.7(3.5, 9.5) months; p=0.2). After spontaneous reinnervation less synkinesis was noted (Sunnybrook synkinesis: 3.0(2.0, 3.0) vs. 5.5(4.75, 7.0); p=0.02) with ES. Discussion: We find no evidence that ES prevents or delays reinnervation or increases synkinesis in facial paralysis.