Location of collateral sprouting of donor nerve following end-to-side neurorrhaphy.

Various studies have demonstrated collateral regeneration of the donor nerve following end-to-side neurorrhaphy, but the location of collateral sprouting remains controversial. In a rat end-to-side neurorrhaphy model we isolated nerve fibers from the donor nerve at the neurorrhaphy site utilizing a micro-tease technique. We found that axons sprouted collaterally from a myelinated nerve fiber at the node of Ranvier. Based on this preliminary result we conclude that myelinated nerve fibers could sprout collateral branches at the node of Ranvier at an end-to-side neurorrhaphy site. These findings show that end-to-side neurorrhaphy may be an alternative for peripheral nerve repair.