Muscle Flap Mass Preservation by Sensory Reinnervation with End-to-Side Neurorrhaphy: An Experimental Study in Rats

ABSTRACT The purpose of this study was to determine whether sensory reinnervation with end-to-side neurorrhaphy preserves muscle mass in pedicled muscle flaps. A new muscle flap model innervated by the common peroneal nerve (CPN) was tested in rats. Animals were divided into group 1 (CPN transected without repair), group 2 (CPN transected and immediately repaired by end-to-end neurorrhaphy), and groups 3A and 3B (CPN transected and repaired with the sural nerve, by end-to-end and end-to-side neurorrhaphy, respectively). We evaluated the muscle-preserving effect by measuring muscle weight and performed histological and morphometric analyses 3 months after the procedure. Sensory reinnervation significantly preserved the muscle mass, although less than motor reinnervation. There was no significant difference between the end-to-end and end-to-side procedures. Results of morphometric analysis in each group paralleled those of mean muscle weight. Sensory reinnervation with end-to-side neurorrhaphy appears to be useful in the preservation of muscle flap mass.