Various Vein Conduit Modalities for Nerve Regeneration in Rats

Youk, Myung Soo; Shin, You Sik; Kim, Hyung Soo; Shin, Young Jin

Abstract

Over the years, many surgeons have used various natural and synthetic materials to bridge the nerve defect. However, none of these materials has surpassed the effectiveness of the nerve autograft. Among natural materials, a vein graft has been used as conduit for nerve regeneration in both research protocols and clinical situations. Unfortunately, the comparison of various research reports is difficult, for each research has employed a different experimental model and method of evaluation for the study of the nerve regeneration. This study introduced various modifications of the vein graft technique, and investigated several vein graft models in an attempt to find the most effective formulation . Four vein graft models were employed: 1) the empty vein graft, 2) the inside-out pattern vein graft, 3) the vein graft filled with skeletal muscle strips, 4) the inside-out pattern vein graft filled with skeletal muscle strips. Regeneration was assessed with gross appearance, histologic examination and electromyography(EMG). In the vein graft filled with muscle strips, there was the increased axonal diameter, myelin sheath thickness, ratio of myelinated axon to unmyelinated axon, and conduction velocities. The result showed that any vein graft filled with muscle strips is superior to the empty vein graft and the inside-out pattern vein graft model which are not filled with muscle strips. It is concluded that the nerve repair using a vein graft filled with skeletal muscle strips can be effectively employed in the clinical field. Further study should be aimed at the regeneration of a longer distance nerve gap and its clinical application.