Experimental Study On The Effect Of Different Suture Methods On Nerve Regeneration

Objective:Peripheral nerve injury is very common in clinical practice and there is currently no most effective method of treatment.In order to solve this problem,we designed the animal nerve injury model for autologous nerve transplantation for microsurgical technique.The effect of the four experimental groups on the repair of nerve injury was analyzed,and the reason was analyzed,which provided the experimental basis for obtaining the ideal method of peripheral nerve transplantation.Methods: 60 SD rats were randomly divided into four groups: A?B?C and D;15 rats in each group;the right lower limb was the experimental side and the left lower limb as the control side.Each rat was treated with the lower limb,and the left lower limb was not treated,and then compared between the groups.Preoperative conventional surgical instruments were sterilized and the animals were weighed.The rats were anesthetized by intraperitoneal injection of 3% pentobarbital sodium 0.2ml / 100 g by weight,and then half of the dose was given,andthen gradually dosing to anesthesia satisfaction.Intraoperative observation of rat vital signs was conducted,and anesthesia after the onset of the rat prone position fixed to the animal test bed and the surgical area(surgical limb gluteal muscle to the ankle flexor side of the skin)after shearing.2% the medical iodophor solution disinfected,conventional shop towel,and the right side of the thigh in the middle of the incision,and from the right side of the femur after 1/3 across the popliteal fossa to the top of the calf,in the back of the thigh muscle blunt separation revealed sciatic nerve.Take care not to damage the nerves and blood vessels and nourish the blood vessels.Each group was treated as follows: Group A: To avoid the sciatic nerve to support the blood vessels,and select the sciatic nerve cut position in the lower edge of the piliformis muscle outlet 1cm,and the second cut the location of the sciatic nerve for the distal end of the anastomosis is 1cm.This segment was used as a transplanted sciatic nerve,completely free from surrounding tissue.Under the double binocular microscope,the proximal and distal ends of the transplanted neurons were placed in the same direction(The surgical microscope transferred to the appropriate location to ensure a clear vision,the first two ends of the match,if no retraction,indicating that the two ends can be no tension in the match.It will be on the section of the nerve bundle,mesangial paraphase and so on one by one together,then prepare 8-0 non-invasive suture began to suture,in the two ends of the level of both sides of the left and right sides of the stitching,retaining long lines as traction,And then between the two fixed-point line,the outer membrane one by one line off the line suture.After the suture of the anterolateral epicardium,the assistant lifts the contralateral traction line,turns the nerve tip 180 ° to the left and right,and suture the outer serosa in the same way.Stitching process,if the emergence of nerve bundles,micro-tweezers can be used to gently push the exposed nerve beam,and then continue to suture,knotting on both sides of the end of the nerve just right for the best fit.Too tight or too loose is not conducive to nerve regeneration.Group B: The sciatic nerve was transplanted with the surrounding tissue and nourish the blood vessels completely free,reversing the proximal and distal,retrograde placement,sciatic nerve outer suture.Group C: According to the specific situation of the sciatic nerve of the sciatic nerve,free from a soft tissue,which contains nourish the blood vessels,and retained not to be removed,with the same method as the previous cut 1cm sciatic nerve as a transplant,in situ,and a distal consistent antegrade epicardial placement sciatic nerve.Group D: the transplanted nerve with nourishing blood vessels in the proximal and distal,retrograde placed,sciatic nerve outer membrane suture.Observation of the group after the suture of the nerve tension,the effect is satisfactory,layer by layer suture muscles,subcutaneous fascia and skin,with sterile gauze bandage incision,put back cage feeding.The rats were sacrificed at 4,8 and 12 weeks after treatment,and the effects of nerve graft were observed by general observation and anatomical observation,electrophysiological examination,tibial anterior muscle wet weight test and regenerated axon recovery rate.Results: 1.General observation: 4 weeks after almost all rats were limping gait,foot,dorsiflexion dysfunction,varying degrees of foot ulcers,most of the emergence of nails dim or even fall off,and tibialis muscle atrophy was obvious.At the end of 8 weeks and 12 weeks,and the rat foot was improved,and the dorsiflexion function was restored,and the ulcer was completely healed,and the muscle atrophy was gradually restored.The general condition of group C and group D was better than that of group A and group B;2.Microscopic anatomy: 4 weeks after the sciatic nerve HE staining sections observed under light microscope showed nerve fiber degeneration,edema,accompanied by nerve regeneration,myelin has begun to appear.C group and group D can be seen that the new myelination is more with a small amount of myelin degeneration,edema,disintegration and active Schwann cell proliferation in the proximal anastomosis of the transplanted nerve,and some regenerated axons pass;Groups A and B can be seen that the new myelin formation is less,with a large number of myelin deformations,edema,and disintegration.After 8 weeks,12 weeks C,D group showed dense myelination,uniform distribution ? high maturity ? more regenerative nerve fibers? arranged more regular? the surrounding connective tissue less growth?regenerated axons through the distal anastomosis into the sciatic nerve Schwann cell cord and to the distal growth;A,B group can be seen myelination sparse,arranged disorder,scattered in the blood vessels,regeneration of nerve fibers less,irregular arrangement of nerves,and the surrounding connective tissue hyperplasia increased significantly.3.The results of group C and group D were superior to those of group A and group B(P <0.01)in nerve conduction velocity,tibial anterior muscle wet weight and regenerated axon recovery rate.That is,the blood supply group is better than without blood group.There was no significant difference between group C and group D(P <0.05).There was no significant difference between group A and group B(ie,between row and retrograde placement).Conclusion: The effect of different suture method on the regeneration of nerve transplantation:1.Autologous nerve transplantation with blood supply is superior to autologous nerve transplantation without blood supply.2.There was no significant difference in the effect of suturing and retrograde placement of adventitial suture on autologous nerve transplantation.