Abstract: Fibrin Glue Augmentation of Nerve Repairs Does Not Impede Nerve Recovery in an Animal Model (2011 SACNAS National Conference)

Friday, October 28, 2011

Hall 1-2 (San Jose Convention Center)

Andrew Bowen , University of California, Irvine, Irvine, CA

Christina Dolores , University of California, Irvine, Irvine, CA

Ryan Vitali, MD , Department of Orthopedic Surgery, University of California, Irvine, Irvine, CA

Gregory Rafijah, MD , Department of Orthopedic Surgery, University of California, Irvine, Irvine, CA

Tahseen Mozaffar, MD , UC Irvine-MDA ALS and Neuromuscular Center, University of California, Irvine, Irvine, CA

Ranjan Gupta, MD , Department of Orthopedic Surgery, University of California, Irvine, Irvine, CA

Segmental nerve defect repair remains challenging for surgeons. Fibrin glue can be employed to expedite surgical procedures and keep spatial orientation of the nerve for optimal recovery. However, surgeons hesitate using fibrin glue due to risk of inhibiting regeneration. The purpose of these experiments was to evaluate if fibrin glue is inhibitory to nerve regeneration. A 10mm critical size defect was created in Sprague-Dawley rats with three forms of repair: group I, collagen type-I conduit; group II, collagen type-I conduit filled with fibrin glue; group III, autologous nerve graft. A sciatic functional index (SFI) test evaluated functional motor recovery. Electromyography (EMG), immunohistochemistry (IHC), and histomorphometry including number of myelinated axons and G-ratios analyzed nerve regeneration. Regeneration and remyelination was significantly greatest in the autograft group, reconfirming autograft as the gold standard. At twelve weeks, SFI revealed comparable functional motor recovery between the conduit groups; specifically, SFI indices of the two groups were similar. EMG results of these two groups were essentially indistinguishable. Although ANOVA testing showed disparities between conduit groups in number of myelinated axons and G-ratios, differences were not statistically significant. IHC revealed macrophage levels and scarring in conduit groups nearly identical. The autograft group showed significantly greater recovery with respect to nerve conduit groups. Our data shows fibrin glue does not impede regeneration even with a barrier in the fibrin glue-filled conduit. No functional, electrophysiological, or morphometric differences were observed between conduit groups. The data supports using fibrin glue without deleterious effects on nerve regeneration and remyelination.