title: Processed allografts and type I collagen conduits for repair of peripheral nerve gaps.
abstract: Autografting is the gold standard in the repair of peripheral nerve injuries that are not amenable to end-to-end coaptation. However, because autografts result in donor-site defects and are a limited resource, an effective substitute would be valuable. In a rat model, we compared isografts with Integra NeuraGen (NG) nerve guides, which are a commercially available type I collagen conduit, with processed rat allografts comparable to AxoGen's Avance human decellularized allograft product. In a 14-mm sciatic nerve gap model, isograft was superior to processed allograft, which was in turn superior to NG conduit at 6 weeks postoperatively (P < 0.05 for number of myelinated fibers both at midgraft and distal to the graft). At 12 weeks, these differences were no longer apparent. In a 28-mm graft model, isografts again performed better than processed allografts at both 6 and 22 weeks; regeneration through the NG conduit was often insufficient for analysis in this long graft model. Functional tests confirmed the superiority of isografts, although processed allografts permitted successful reinnervation of distal targets not seen in the NG conduit groups. Processed allografts were inherently non-immunogenic and maintained some internal laminin structure. We conclude that, particularly in a long gap model, nerve graft alternatives fail to confer the regenerative advantages of an isograft. However, AxoGen processed allografts are superior to a currently available conduit-style nerve guide, the Integra NeuraGen. They provide an alternative for reconstruction of short nerve gaps where a conduit might otherwise be used.
authors.affiliation: Division of Plastic and Reconstructive Surgery, Washington University School of Medicine, 660 South Euclid Avenue, Campus Box 8238, Saint Louis, Missouri 63110, USA.
authors.forename: Elizabeth L
authors.initials: EL
authors.lastname: Whitlock
authors.forename: Sami H
authors.initials: SH
authors.lastname: Tuffaha
authors.forename: Janina P
authors.initials: JP
authors.lastname: Luciano
authors.forename: Ying
authors.initials: Y
authors.lastname: Yan
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Hunter
authors.forename: Christina K
authors.initials: CK
authors.lastname: Magill
authors.forename: Amy M
authors.initials: AM
authors.lastname: Moore
authors.forename: Alice Y
authors.initials: AY
authors.lastname: Tong
authors.forename: Susan E
authors.initials: SE
authors.lastname: Mackinnon
authors.forename: Gregory H
authors.initials: GH
authors.lastname: Borschel
mesh_terms: D020341:Absorbable Implants; D000818:Animals; D024042:Collagen Type I / Q000494:pharmacology* / Q000627:therapeutic use; D004195:Disease Models, Animal; D020439:Growth Cones / Q000502:physiology; D007797:Laminin / Q000378:metabolism; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D046529:Microscopy, Electron, Transmission; D009413:Nerve Fibers, Myelinated / Q000378:metabolism / Q000648:ultrastructure; D036421:Nerve Fibers, Unmyelinated / Q000378:metabolism / Q000648:ultrastructure; D009416:Nerve Regeneration / Q000502:physiology; D019635:Neurosurgical Procedures / Q000379:methods*; D059348:Peripheral Nerve Injuries; D010525:Peripheral Nerves / Q000601:surgery* / Q000637:transplantation*; D051381:Rats; D011917:Rats, Inbred Lew; D020127:Recovery of Function / Q000502:physiology; D020426:Sciatic Neuropathy / Q000601:surgery; D023001:Transplantation Tolerance / Q000502:physiology; D014184:Transplantation, Homologous / Q000379:methods*; D016896:Treatment Outcome
chemical_list: D024042:Collagen Type I; D007797:Laminin