Stimulation of peripheral nerve regeneration by an isolated nerve segment

An experimental model in rats was used to assess the stimulant effect of an isolated nerve segment on peripheral nerve regeneration. In a first group of animals, 14 mm of the femoral nerve was removed unilaterally and the gap was bridged with femoral vein taken from the other side. In a second group, the intervention differed in that a 2-mm nerve segment was introduced at the center of the bridging vein. Histological examination was done three months after the operation. In the first group, a newly formed nerve structure was found in the proximal part of the vein, with incipient myelination of nerve fibers. The frequency of nerve fibers decreased with the distance from the proximal nerve stump, with no fibers present in the distal part of the vein. In the second group, a well-developed nerve structure was noted in both the proximal and the distal parts of the bridging vein, with myelination well advanced. Possible reasons for the positive effect of an isolated nerve segment in bridging nerve gaps are discussed.