Neuromuscular Retraining versus BTX-A Injection in Subjects with Chronic Facial Nerve Palsy, A Clinical Trial

INTRODUCTION: Chronic facial nerve palsy has long been known to negatively affect the quality of life in patients. The present study aimed to investigate the efficacy of Botulinum Toxin A (BTX-A) and neuromuscular retraining therapy (NMRT) in the symmetry of chronic facial palsy. MATERIALS AND METHODS: Two groups, namely experimental and control, were considered each consisting of 13 patients. The study population included a total of 15 female subjects. The BTX-A was injected into the synkinetic muscle in the experimental group; nevertheless, the patients in the second group participated in special neuromuscular retraining. The rate of reducing synkinesis and symmetrical improvement was evaluated using the Facial Grading System (FGS) after 4 months of treatment. The independent t-test was performed to compare the two groups. RESULTS: According to the Sunnybrook FGS, the mean changes in Sunnybrook scores in the experimental and neuromuscular retraining groups were 3% and 24%, respectively. The comparison of the mean scores of the two groups was statistically significant after the interventions (P=0.033). A variable ratio of statistically significant improvement was observed in synkinesis in both groups following the treatment (P=0.041). In addition, by comparing the synkinesis scores between the two groups, the reduction of synkinesis was observed to be greater in the neuromuscular retraining group (P=0.041) after the treatment. CONCLUSIONS: The findings of the current study indicated that special neuromuscular retraining leads to significant improvement in the FGS score, compared to botulinum toxin therapy alone. Moreover, it was observed that facial symmetry can be treated with special neuromuscular retraining and the patient can overcome synkinesis.