Regeneration through nerve isografts is independent of nerve geometry

Investigators have theorized that tortuosity in nerve grafts may adversely affect nerve regeneration. This study investigated the effect of graft configuration and redundancy on regeneration across 2.5-cm rat sciatic nerve isografts. Thirty-two Lewis rats were randomized to four nerve grafting groups defined by gap distance and isograft conformation. In Group 1, grafts were interposed into a 2-cm gap, resulting in mild graft redundancy. In Groups 2 and 3, grafts were tacked in sinusoidal or omega-shaped configurations, respectively, to bridge a 0.5-cm gap. In Group 4, grafts were interposed after 1 cm of native sciatic nerve was resected, resulting in no graft redundancy and an interstump distance of 2.5 cm. At 6 weeks, nerve tissue was harvested; subsequent histomorphometric analysis revealed no significant differences in regeneration between groups. These data suggest that regeneration through isografts is independent of the graft geometry and redundancy.