Modification of tension on muscle insertion improves smile in free-muscle transplantation

A functional free muscle without creation of different vectors and tension adjustment is an insufficient substitute for the mimetic muscles in the reanimation of facial paralysis. Placement of the lower 3 slips of the serratus anterior muscle and their tension adjustment were revised in 2 patients with facial paralysis to provide stronger upper lip movement and coordinated movement of the corner of the mouth superiorly and laterally. The slips were harvested with gradually decreasing lengths and separated from each other on both sides of their common neurovascular pedicle. The 9th slip was oriented at 55 to 60 degrees to the upper lip with the greatest tension. The 8th slip exerted original strength of tension to the modiolus at 45 degrees. The 7th slip was placed horizontally with the least tension. The results were evaluated according to open and closed lip smile and excursion of the modiolus. Stronger upper lip elevation and sufficient elevation of the modiolus with a proper 3-directional movement were demonstrated.