Nerve Regeneration Using a Vein Graft Conduit filled with Hyaluronic Acid in a Rat Model

ABSTRACT

PURPOSE: The vein graft was considered as a useful conduit for nerve defect. But the problem is that it might be collapsed in long vein graft state. A new experimental model using vein graft filled with hyaluronic acid was considered. METHODS: Thirty rats were used for the experimental animal. In group I, one side of the femoral nerve was exposed and a segment was removed about 15mm. The neural gap was connected with nerve graft. In group II, the nerve gap was connected with vein graft only. In group III, the nerve gap was connected with vein graft filled with hyaluronic acid. A walking track analysis was made periodically for 2 months and NCV(nerve conduction velocity) was executed at the end of the experiment. And morphologic studies were also done for all groups RESULTS: In a walking track analysis, the toe-spread was widen and the foot-length was lengthened. The recovery of the toe-spread and foot length was checked 2 weeks interval, periodically for two months. The SFI (sciatic function index) was -52.5+/-8.2 in group I, -68.1+/-4 in group II, -55.3+/-7.9 in group III. In electrophysiological study, NCV(nerve conduction velocity) was 26.71+/-3.11m/s in group I, 17.94+/-4.35 m/s in group II, 25.69+/-2.81m/s in group III. The functional recovery in group I and III was superior to that the group II statistically(p<0.05) Under electromicroscopic study, the number of the myelinated axons were 1419.1+/-240 in group I, 921.7+/-176.8 in group II, 1322.2+/-318 in group III. The number of the myelinated axons were much more in group I and III than group II statistically (p<0.05). CONCLUSION: This study suggested that the vein graft filled with hyaluronic acid is more effective than vein graft only for the conduit of the nerve gap. It was thought that the technique could be used in clinical cases with nerve defects as an alternative method to classical nerve grafts.