Autogenous vein graft as an alternative to autogenous nerve graft for bridging the gap of the peripheral nerve has been widely accepted. The purpose of this study was to find the comparative superiority between the two grafting techniques of inside-in and inside-out vein graft in rat model.

Thirty-three Sprague-Dawley rats were divided into three experimental groups: inside-in vein graft (group A), inside-out vein graft (group B) and control group. In group A, 15 mm jugular vein was grafted to a 10 mm gap created in the sciatic nerve. In group B, the same procedure was performed with group A, however, the vein was pulled through itself and its normal orientation was inverted before grafting. To compare the results of the two groups, electromyography and histologic studies were performed at 4, 8 and 12 weeks postoperative.

In the electromyographic study, the mean of peak amplitude of compound motor action potential in group B was significantly higher than in group A at each experimental week. In the light and electron microscopic study, group B had more abundant regenerated axons and myelinized axonal fibers than group A at 4 weeks. At 8 and 12 weeks, there were no significant differences in the numbers and extents of myelinization of regenerated axons in both groups.

This study demonstrates that inside-out vein grafting technique induces more faster axonal regeneration and earlier reinnervation to the denervated distal muscles in rat model.