Objective: To investigate how botulinum toxin type A (BoNT/A) enhances fat graft survival in the absence of muscle activity, aiming to clarify its non-muscle-mediated mechanisms.

Hypothesis: BoNT/A improves fat graft retention through mechanisms beyond muscle paralysis. Using the muscle-deficient subcutaneous skull area of nude mice, we propose that BoNT/A promotes graft survival via non-muscular pathways when administered prior to fat grafting.