Acellular nerve allografts in peripheral nerve regeneration: A comparative study

Introduction: Processed nerve allografts offer a promising alternative to nerve autografts in the surgical management of peripheral nerve injuries where short deficits exist. Methods: Three established models of acellular nerve allograft (coldpreserved, detergent-processed, and AxoGen-processed nerve allografts) were compared with nerve isografts and silicone nerve guidance conduits in a 14-mm rat sciatic nerve defect. Results: All acellular nerve grafts were superior to silicone nerve conduits in support of nerve regeneration. Detergent-processed allografts were similar to isografts at 6 weeks postoperatively, whereas AxoGen-processed and cold-preserved allografts supported significantly fewer regenerating nerve fibers. Measurement of muscle force confirmed that detergent-processed allografts promoted isograft-equivalent levels of motor recovery 16 weeks postoperatively. All acellular allografts promoted greater amounts of motor recovery compared with silicone conduits. Conclusion: These findings provide evidence that differential processing for removal of cellular constituents in preparing acellular nerve allografts affects recovery in vivo.