The purpose of this study was to compare the nerve regeneration and recovery of innervated muscle activity according to different methods of nerve repair. Nerve defect was made by resection of 10mm-long segment of the right sciatic nerve in Sprague-Dawley rats.
Group A was not repaired, group B was repaired with autogenous nerve graft using eontralateral sciatic nerve segment and group C was with silastic tube.
At 1, 2, and 3 months after the repair, electrophysiological muscle activity from the gastrocnemius muscle was recorded and histological study showing nerve regeneration was done.
The results -obtained were as follows
1. Histologic observations
In non-repaired group, fibrosis and Wallerian degeneration of the nerve fiber were observed at 1 month. At 2 and 3months~ there were proliferation of Schwarm cell and regeneration of axons. Little connection was noted between proximal and distal stumps, however.
In autogenous nerve grafted group, prominent axonal proliferation and connection of nerve fibers between proximal and distal slumps were noted.
In silastic repaired group, nerve fibers were regenerated through silastic tube. Diameter of the nerve fibers increased with increasing time.
2. Electrophysiologic observations
Electromyographic activity of the normal gastrocnemius muscle in response to electrical stimulation was 1,215 37 (1i=2)N:V. At 3 months, a significant improvement of muscle activity was noted in both the autogenous nerve graft group and the silastic tube group : Compared with the normal control muscle, the former showed 2/3 and the latter 1/2 reoavery.
These results indicate that autogenous nerve graft is better than using silastic tube. However, it is suggested that silastic tube may well be employed for the nerve repair.
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