Biofeedback and Motor Reeducation in Facial Synkinesis: Functional Recovery Five Years After Peripheral Facial Palsy

Abstract

Introduction

Up to one in three patients with peripheral facial palsy develops facial synkinesis during the recovery process, and nearly 30% continue to experience symptoms one year after the initial event. Facial synkinesis is characterized by involuntary movements accompanying voluntary facial actions and represents one of the most disabling functional sequelae of the condition, affecting facial expression, communication, and social participation. Although recovery opportunities are often considered limited once chronicity is established, advances in neurorehabilitation suggest that motor reorganization may persist beyond the traditional recovery period. This report presents the case of a patient with chronic facial synkinesis of five years’ duration treated with biofeedback and motor reeducation.

Objective

To describe the clinical, functional, and neurophysiological outcomes of a patient with chronic facial synkinesis secondary to peripheral facial palsy treated with a biofeedback-based motor reeducation program.

Methodology

Case report. A 63-year-old woman with a five-year history of right peripheral facial palsy, previously treated with botulinum toxin type A without significant functional improvement, was referred to physiotherapy due to persistent oculo-oral synkinesis, facial asymmetry, and limitations in social participation.

Assessment included the House-Brackmann scale, Sunnybrook Facial Grading System, Synkinesis Assessment Questionnaire (SAQ), WHODAS 2.0, and muscle activity recordings obtained through surface electromyography integrated into the biofeedback system. A 15-session intervention was delivered over four weeks and consisted of two phases: inhibition of hyperexcitability and motor relearning, followed by selective motor reeducation assisted by biofeedback and visual feedback.

Results

Significant clinical and functional improvements were observed following the intervention. House-Brackmann classification improved from grade V to grade II, while the Sunnybrook score increased from 11 to 88 points. The SAQ score decreased from 73.3 to 31 points, indicating a substantial reduction in synkinesis severity. Likewise, WHODAS demonstrated an improvement from complete to mild restriction in the community, social, and civic participation domain.

Muscle activity recordings obtained through the biofeedback system revealed favorable reorganization of facial activation patterns. Frontal muscle activity decreased from 24.7 µV to 20.7 µV, whereas zygomaticus activity increased from 15.6 µV to 22.6 µV and risorius activity increased from 9.2 µV to 18.7 µV. Clinically, progressive reduction of oculo-oral synkinesis, restoration of dynamic facial symmetry, improved smile control, resolution of involuntary drooling, and reintegration into previously avoided social activities were observed.

Conclusions

Biofeedback combined with motor reeducation represents a promising strategy for promoting functional recovery in patients with chronic facial synkinesis. This case demonstrates that motor reorganization and clinical improvement remain achievable even five years after peripheral facial palsy, supporting the potential of neurorehabilitation interventions to reduce aberrant activation patterns and enhance social participation.