Effects Of Motor Versus Sensory Nerve Autografts On Peripheral Nerve Regeneration

Purpose Autologous nerve grafting is the current standard of care for nerve injuriesresulting in a nerve gap.But useing sensory grafts to reconstruct motor defects, theconsequences of mismatches between graft and native nerve are unknown. Motorpathways have been shown to preferentially support motoneuron regeneration.Functional outcome of motor nerve reconstruction depends on the magnitude, rate, andprecision of end organ reinnervation. This study examined the role of pathway type onregeneration across a mixed nerve defect.Method&Results Thirty-six SD rats underwent tibial nerve transection and receivedisogeneic motor, sensory or mixed nerve grafts.Histomorphometry of the regeneratingnerves at4weeks demonstrated robust nerve regeneration through both motor andmixed nerve grafts.In contrast, poor nerve regeneration was seen through sensory nervegrafts, with significantly decreased nerve fiber count, percent nerve, and nerve densitywhen compared with mixed and motor groups (P＜0.05).Conclusion These data suggest that use of motor or mixed nerve grafts, rather thansensory nerve grafts, will optimize regeneration across mixed nerve defects.