Experimental study of vascularized nerve grafts: multifactorial analyses of axonal regeneration of nerves transplanted into an acute burn wound.

Rat sciatic nerves were used in a comparative study of both vascularized and free nerve grafts that were transplanted into an acute burn wound. Electromyographic analyses of axonal regeneration were done at intervals from week 1 through week 24 after surgery. Biopsied sciatic nerves were processed for morphometric studies with the use of a fiber caliber analyzer. Motor nerve conduction velocity was faster in the vascularized nerve graft than in the free nerve graft until week 24 after surgery. Regenerated axons appeared earlier in the vascularized nerve grafts than in the free nerve grafts, and the density of large regenerated axons was greater in the former than in the latter group. It is suggested that preserving the vascular system of vascularized nerve grafts would decrease the likelihood of fibrosis and result in smooth regeneration of axons.