Experimental Study On A Heterogeneous Biological Amnion To Repair Peripheral Nerve

ObjectiveTo investigate feasibility of biological amnion in using a biological amnion to repair heterogeneous animal peripheral nerve.Methods64 healthy SD white rats were randomly divided into two groups(each group,24).The control group treated with standard neurorrhaphy alone, the repair site of the experimental group were then wrapped with a piece of human amniotic membrane.Maded general observation and compared the conduction of velocity of the distal nerve and histologic evaluation of regeneration of 8 sciatic nerves of the rats of each group was made after sacrificing the rats in 4,8,12and16 weeks after sugery, Observated the results with a transmission electron microscope between experimental group and control group12 and 16 weeks after sugery, All data were analyzed with the spss13,0 software.Results1.General observationEach affected extremity suffered swelling and distension in two weeks after surgery. In the experimental group,the time of lameness is shorter and the cutaneous ulcer of the operative foot soles or toes healed sooner than the control group.The amniotic membrane partly absorbed in 4 weeks after surgery,absorbed in 8 weeeks.In the experimental group there is no obviously conglutination in the repair cite of nerve and the nerve's activity is acceptable.The neuratrophy of the distal nerve in the experimental group recovered faster than the control group.In the control group,there is gradually aggratated conglutination and cicatrix in the repair cite after surgery, the nerve's activity gradually lost.2.Nerve electrophysiologyThe detection of conduction of velocity and evoked potential of the operation nerve: the control group is lower than the experimental group (P﹤0.05): The is obviously statistical significance between two groups.3.Histological observationLight microscope:the growth of nerve fibers can be found in the repair cite of two groups.In the experimental group there is less inflammatory cell surrounding nerve fibers and less desmocyte hyperplasia than the control group.Electron microscope:the distal axon and myelin sheath of the experimental group is thicker and the Schwann cell is abundant compaired to the control group.ConclusionThe heterogeneous biological amnion is a ideal peripheral nerve repair material:①reduce the cicatrix and inflammatory reaction of the the repair site;②increased distal axon,fiber diameters and myelin thickness;③satisfactory biocompatibility and degradation.