Introduction This study investigated the effect of combining hypoglossal-facial nerve "side"-to-side neurorrhaphy and electrical myostimulation in a rat model of facial palsy. Methods Rats with facial nerve crush injury were subjected to control condition, monotherapy of either neurorrhaphy or electrical myostimulation, or bitherapy of the two treatments. After 1, 3, and 6 months, rats were performed the facial symmetry evaluation, electrophysiological examination and the retrograde labeling of motor neurons. Results As early as 3 months after injury, face symmetry significantly improved in rats of the bitherapy group. At 3 or 6 months after injury, either the parameters of electrophysiological examination or the number of labeled motor neurons were significantly increased in the bitherapy group than in any other group. Discussion The combination of neurorrhaphy and electrical myostimulation effectively promoted the functional recovery after facial nerve crush injury.
Keywords: Animal model; Electrical myostimulation; Facial palsy; Motor action potential; Neurorrhaphy; Retrograde labeling.