The Phrenic Nerve as a Motor Nerve Donor for Facial Reanimation with the Free Latissimus Dorsi Muscle

Free functional muscle transfer for acquired facial paralysis most often involves two stages. In this report, we describe single-stage free muscle transfer using the phrenic nerve as the donor motor nerve. Six patients with unilateral facial paralysis underwent single-stage facial reanimation using a free latissimus dorsi muscle with the ipsilateral phrenic nerve as the donor nerve. These cases were retrospectively studied to review technique and to determine outcomes including time to muscle reinnervation, patient satisfaction, smile symmetry, and complications. The mean age was 33 years. Five patients had complete unilateral facial paralysis and one had incomplete. There was no flap loss. The transferred muscle demonstrated active contraction in all patients at a mean of 14 weeks postoperatively (range, 12 to 16 weeks). Good dynamic symmetry was achieved by 6 to 9 months in all patients. All patients underwent rehabilitation including nerve reeducation. No clinically significant pulmonary morbidity was observed after the unilateral transection of the phrenic nerve. Using the phrenic nerve in free muscle transfer for facial paralysis allows a single-stage procedure with no requirement for nerve grafting and a rapid reinnervation time, shortening the time required for restoring facial animation.