The Establishment Research About The Rat Model Of Ventral Root Avulsion

Pelvic fracture is a common flacture in clinic,which may induce the Ventral root avulsion.or ventral injury with the functional impairment of movement and feeling of lower limb.Nowadays,we have no efficient method to deal with them.At first,we need an animal model of Ventral root avulsion which has not been reported yet.in this article,we emphasis on the building of an animal model of Ventral root avulsion in order to proved the foundation for the further studies about the efficiency of therapy.Part oneObjective To discover a variation of rat sciatic nerve anatomy.Methods:20 adult SD rats were dissected to discuss the rat sciatic nerve anatomy.17 rats's nerve roots of sciatic nerve are L4-6,While others are L4-5.and each tile has its two hypotypes.We also comfinned that L4-5 is the permanent dominant nerve of biceps femoris,triceps surae and tibial muscle,and L6 is the main nerve dominant of triceps surae,but in two rats,L6 has nothing to do with biceps femoris,triceps surae and tibial muscle.Results We results indicate that the components of the sciatic nerve vary from L4 to L6.we also confirm the biceps femoris,triceps surae and tibal muscle's dominant nerve root and contribution through EMG.So it builds a solid base of establishment of the animal model of sacral plexus root avulsion.Part TWOObjective Establish the animal model of sacral plexus root avulsion.Methods 20 adult SD rats were chosen to establish the anirnal model of sacral plexus root avulsion at random after avulsing the right L4-6 out of intervertebral foramina.Then,the models were evaluated by the observation of the survival rates of the rates,BBB scores,SEP and SNAP,horse radish peroxidase(HRP) tracing;weight and muscle fiber CSA(cross section area) of double biceps femoris,triceps surae and tibial muscle.Results 1.The survival rate was 95%because 1 rat had died within 6 weeks postoperatively.And the mean BBB scoring was 10.78±3.15,while the normal was 24.2.The achievement ratios to establish the model was 89.5%according to the criteria of SEP.3.2 rats were positive of the HRP reaction in the spinal segment of L1-4.so the achievement ratio of them was 89.5%according to the criteria of HRP reaction.4.We found a remarkable significances beteen weight and muscle fiber CSA of double biceps femoris,triceps surae and tibial muscle.5,We can find muscle fiber atrophy,nucleus shift,muscle satellite cell which indicate denervation.Conclusion:Avulsion of L4-6 nerve root in the rats is the feasible and ideal model to establish the model of Ventral root avulsion.