Research Technician University of Wisconsin - Madison Neurosurgery
Disclosure(s):
Ethan J. Mickelson, Sc.M: No financial relationships to disclose
Introduction: More than twenty million Americans are estimated to suffer from nerve injuries. These injuries are fraught with upper and lower extremity disability, with up to 33% of injuries resulting in incomplete nerve recovery. For severe nerve injuries, tensionless epineural coaptation of the nerve is the preferred treatment. The procedure involves transections of the injured nerve ends, nerve harvesting from a donor site, and segmental grafting with end-to-end microsuturing. Currently, non-absorbable sutures are the recommended choice for nerve grafts. However, there is limited research to suggest that non-absorbable sutures are superior to absorbable sutures. This study aims to further characterize the relationship between suture choice and nerve repair outcomes. We hypothesize no difference in the outcomes between absorbable and non-absorbable sutures.
Methods: This study compares the efficacy of non-absorbable 9-0 nylon sutures, absorbable 9-0 Vicryl sutures, and fibrin glue for sciatic nerve grafts. Lewis rats (N=36) were randomly assigned to a group, received sciatic nerve grafts, and were allowed 12 weeks of post-operative recovery. Every 4 weeks during recovery, each rat was subjected to functional testing. Following recovery, the graft's immune response and axon regeneration were measured.
Results: The results show that the vicryl group had significantly more axon growth and that there are no significant differences in functional testing or macrophage levels between nylon and vicryl sutures. Each group produced viable nerve grafts after recovery; however, 33% of fibrin glue grafts failed to incorporate anatomically. Furthermore, the immunohistochemistry (IHC) analysis indicates different immune responses for each group. The nylon sutures consistently displayed macrophages surrounding the suture hole, a response noticeably absent from the vicryl sutures.
Conclusion : Ultimately, we have found no significant differences between nylon and vicryl sutures for nerve grafts and would not recommend fibrin glue as an effective treatment option.
