ABSTRACT

Surgical reanimation of long-standing facial paralysis utilizing free muscle transfers continues to be a clinical battleground, due to long rehabilitation and outcome inconsistency. Our technique employing a free rectus abdominus neurovascular flap in a one-step reanimation procedure has the potential for reduced morbidity, better function, and shortened recovery time, compared to previously described two-stage reconstructions. Past efforts at free flap reanimation resulted in facial movements that lacked spontaneity and inappropriately elicited, but the main criticism of the two-stage procedure is that the inter-stage period adds nearly 12 months to an already significant rehabilitation. Our aims are to 1) Demonstrate a novel technique in free flap facial reanimation; 2) Impart clear functional improvement in facial movement, 3) Illustrate via EMG studies quantifiable difference in muscle activity; 4) Reduce the morbidity and shorten the recovery time in free flap facial reanimation. Methods: 5 patients with longstanding unilateral facial paralysis underwent our single –stage facial reanimation. Briefly, the deep inferior epigastric artery and vein are identified and 6-10 cm pedicle length is obtained. The intercostals nerve is stimulated to assure contraction of the muscle segment to be harvested. A 4 by 5 cm segment of muscle is harvested, and then the neurovascular mircoanastamosis were completed. Patients underwent pre- and postoperative EMG testing, and followed postoperatively with EMG testing for an average of 16.2 months (range 6-44 months). Peak muscle activity was recorded from each zygomaticus and levator muscle groups were obtained during voluntary movement. The Facial Grading Scale (FGS), which assesses impairments at rest, voluntary movement, and synkenisis was obtained at each visit. Results: All five patients in the series showed an improvement in FGS at most recent follow-up, with an average score of 41 (range 26-55) and an average improvement of 186%. The average initial EMG readings for the levators were increased from 8.6¼V to 13.6¼V. All five patients displayed increased EMG potential at muscle site, at an average of 115% improvement (range 10-400%) The average EMG readings for the zygomaticus muscle group was increased from 11.2 ¼V to 27.6 ¼V with a mean increase of 219%. Conclusions: The rectus abdominus has the distinct advantage of having tendinous inscriptions surrounding the muscle, making it possible to have reliable points of insertion in the recipient site. The pedicle length of this vascular supply provides ample work distance for a number of insertion and anastomosis options. The rectus abdominus is segmentally innervated from the terminal branches of the lower six intercostals nerves, to sufficiently traverse the distance to the contralateral facial nerve with more than one branch available for anastamosis. Combined with the ability to separate the tissue into several distinct muscle bellies each with its own nerve fascicle, the rectus can be inserted reliably into a number of different structures, to provide consistently firm support and dynamic movement. . The EMG and FGS scores imply that this one-stage reanimation procedure can afford reliably superior clinical outcome.