Experimental Study Of Motor Functional Recovery After Repair Of Sciatic Nerve With Acellular Nerve Allografts In Rat

ObjectiveThe repair of peripheral nerve long defect needs a graft between two ends of nerve to recover the continuous. Presently, the autologous nerve grafting is an important method in reconstructive surgery of peripheral nerve lesions. However, there are still unresolved problems. The availability of autografts is limited and the harvesting of autografts result in donor site morbidity such as sensory defects , scarring and neuroma formation. So the study of ideal graft is an important subject of peripheral nerve surgery. In our former experiment, we have successful made natural biodegradable nerve graft which can promote the peripheral nerve regeneration. This study was designed to investigate the motor functional recovery of regenerated nerve after reconstruction by histochemical methods and electrophysiologic test.MethodsWistar rat was used to make acellular rat sciatic nerve (ARSN) and SD rat was divided into two groups randomly.In experiment group, the ARSN was transferred into the defect of sciatic nerve of 10mm length and the autologous nerve graft was used in control group. The rat was breeded for 6 months after transplanta-tion, the histochemical method and electrophysiologic test were used in different times.ResultsImmediately after surgery, all rats dragged their operated paws and the swelling or ulcer was observed gradually at the skin of foot. After 12 weeks of transplantation, these phenomena disappeared gradually and the tiptoes can stretch followed the foot on ground ; After 24 weeks, the operated leg could walk on the ground and the step tended to be normal; At 12 and 24 weeks, the wet weight of tibialis anterior and the conducted velocity of regenerated nerve were similar to auto-grafts group. There wasnt significant difference between them. Positive acetylcholinesterase histochemical reaction was observed in the gastrocnemias muscle in 12 weeks while the regenerated nerve terminals were found to grow into the motor end - plate; The positive reaction is deeper and lined in the middle of gastrocnemias tidily at 24 weeks. At the same time we saw the regenerated nerve bundle and nerve terminals combining with motor end - plate.Conclusion1 Acellular nerve allograft is an ideal graft for reparing defected nerve.2 After defected sciatic nerve is repaired by acellular nerve al-lografts, the atrophy muscle tissue innervated by which can recover.3 Acellular nerve allografts which repair defected sciatic nerve can improve the regeneration of defected nerve, to recover the trans-duction of the nerve and the innervation to muscle.