Pediatric Gracilis Free Muscle Transfer for Facial Reanimation: A Systematic Review of Outcomes Based on Donor Nerve

Background: The gracilis free muscle transfer (GFMT) is considered a powerful tool in dynamic facial reanimation but lacks consensus on the optimal donor nerve for pediatric populations. Objective: To compare outcomes in pediatric patients receiving a GFMT for facial reanimation based on donor nerve as measured by commissure excursion, facial symmetry, and spontaneity. Method: A systematic review using PubMed, EMBASE, and Google Scholar was conducted to identify articles that investigated primary GFMT for facial reanimation using a variety of donor nerves for reinnervation in patients under 20 years old. Quantitative meta-analysis stratified by donor nerve was conducted. Results: A total of 19 articles with 304 patients were included in our meta-analysis. The masseteric, cross-facial nerve graft, and dual-innervation techniques were included. Pediatric GFMT significantly improves commissure excursion regardless of donor nerve. There were no significant differences between groups in facial symmetry. Conclusion: Significant improvement in oral commissure excursion is seen following GFMT no matter the donor nerve source. Data on reported outcomes in pediatric patients are limited and heterogenous, which limits conclusions on facial symmetry and spontaneity following this procedure. Future research using standardized outcome reporting is needed to determine the optimal nerve to power a GFMT in facial reanimation.