Effect Of Passive Exercise On Neural Functional Recovery Of Rabbits After Peripheral Nerve Crushed Injury

Objective:Regeneration of peripheral nerve after crushed injury is a very complicated course,the recovery of configuration and function is related to degree of injury and suitable therapy. 24 rabbits were used as objects of study in the test. A special advice named Kyphon with aerocyst was used to crush the tibial nerve for establishing model of crushed injury in the condition of sterility.Using strict ways of exercise training of simulating human ,we investigate the effect of passive exercise on neural functional recovery in rabbits after peripheral nerve crushed injury.Method: The 24 rabbits ,12 males and 12 females ,were divided into two groups,the exercise training group and the splinting group.The rabbits in exercise training group was given passive exercise for 20 minutes daily for 3 weeks and the splinting group was only splinted. On the 21st day of injury, the rabbits were anatomized in order to unfold the tibial nerve ,the electrophysiologic indexes were determined ,such as latent period ,amplitude of compound action potentials and conduction velocity .And then,the injury segment of tibial nerve was cut down and was divided into three segments,near ,middle and far segment.They were dyed using modified Mallory' s trichrome staining methods, it clearly showed nerve myelin sheath and axon.And the nerve was dyed using Bielschowsky staining methods and Loyez staining methods to show the nerve axon and myelin sheath. The nerve was magnified 400 times using the system of image analyzing.The histological indexes were determined,such as the thickness of myelin sheath,average numbers of myelinated nerve fiber a per area and diameter of regenerating axon.The triceps of calf was cut down,and weighed up using analysis balance.The muscle was dyed using HE staining methods, the muscle cell were magnified 400 times using the system of image analyzing,and the diameter of the muscle cell were determined.The latency in the exercise training group was shorter than the plintinggroup,and it was significantly different between the two groups (p<0.05); The amplitude was increased in the exercise training group,as compared with the plinting group,but it was no significantly different between the two groups (p> 0.05) .The nerve conduction velocity of exercise training group was bigger than that in the plinting group,it was significantly different between the two groups (p<0.05) .The thickness of myelin sheath , average numbers of myelinated nerve fiber a per area and diameter of regenerating axon was larger than the plinting group. And it was significantly different between the two groups(p<0.05). The wet weight and diameter of musculus triceps surae of exercise training group were bigger than the plinting group, and the former was significantly different between the two groups(p<0.05),but the latter was not (p>0.05) .Conclusion:The passive exercise for rabbits after tibial nerve crushed injury helps to improve the early recovery of motor function.