Outcomes and Innervation of Gracilis for Pediatric Facial Paralysis: A Systematic Review.

Abstract

This systematic review aims to describe and compare outcomes of innervation techniques for gracilis free muscle transfers for facial reanimation in the pediatric population. CINAHL, PubMed, and SCOPUS were systematically queried from inception to November 18, 2025. Eligible studies included pediatric patients (≤ 18 years old) who underwent free gracilis muscle transfer for facial reanimation. Outcomes extracted included commissure excursion, facial asymmetry, validated instruments, patient satisfaction, and complications. Study quality was assessed using the Joanna Briggs Institute appraisal tool. A total of 15 retrospective studies were included for review, covering cross-facial nerve graft, masseteric innervation, and dual-innervation. The mean age at time of surgery was 9.0 ± 0.8 years with a mean follow-up time of 3.0 ± 0.5 years. Muscle innervation was achieved primarily with CFNG (52.1%), followed by masseteric (33.2%). Masseteric innervation generally produced the largest amount of commissure excursion (range: 6.1-8.6 mm), while CFNG also yielded moderate improvements (range: 4.6-6.9 mm). Overall satisfaction was high for all innervation techniques, ranging from 83% to 100%. Complications were infrequent and minor. Gracilis free muscle transfer is safe and effective for pediatric facial reanimation. Masseteric innervation provides strong, volitional smiles, while CFNG provides spontaneous smiles, with dual-innervation offering a balance of the two.