Objective: To investigate the impact of different section injury on the median nerve during peripheral nerve regeneration.
Methods: 18 New-Zealand rabbits were divided into 3 groups. We took the proximal, intermediate and distal nerve segment as donor nerve, the restore ratio of the number of donator fibers to recipient fibers is 1:4. We took the corresponding right side nerve as control, the restore ratio of the number of donator fibers to recipient fibers is 1:1. We then observed the general condition of regenerated nerve, counted the number of regenerated fibers, measured its conduction of velocity and wet weights of musculus flexor digitorum sublimis 3 months after operation.
Results: The numbers of recipient fiber of 3 different groups were as follows: group I: 1747 +/- 375, group I: 1785 +/- 442, group III: 1863 +/- 321; Control goup I: 2234 +/- 364, control group II: 2319 +/- 237, control group III: 2346 +/- 308. The results of conduction of velocity were: group I: 19.5 m/s, group II: 19.9 m/s, group III: 21.3 m/s; Control group I: 57.1 +/- 3.7 m/s, control group I: 56.4 +/- 2.5 m/s, control group III: 56.8 +/- 2.3 m/s. The results of wet weights of musculus flexor digitorum sublines were as follows: group I: 1.7247 +/- 0.0891 g, group II:1.7239 +/- 0.0903 g, group III: 1.7253 +/- 0.0798 g. Control group I: 2.0448 +/- 0.1013 g, control group II: 2.0433 +/- 0.0861 g, control group III: 2.0456 +/- 0.0947 g.
Conclusion: The amplification phenomenon exist in every group, the amplified ratio augment according to the distance of the site from neuron, but the conduction of velocity is decreased gradually . The wet weights of musculus flexor digitorum sublines has no significant difference between 3 groups.