Hyaluronic acid/carboxymethyl cellulose directly applied to transected nerve decreases axonal outgrowth.

Neuroma management is an unresolved problem. Biomaterials to limit unwanted axonal growth could be a tool to manage neuroma. Hyaluronic acid/carboxymethyl cellulose (HA/CMC) is an antiadhesive, biodegradable material that is nontoxic to nerve. The purpose of this study was to evaluate the efficacy of this biomaterial to limit axonal growth. Rats received a sciatic nerve transection and repair with a short conduit (5 mm) containing HA/CMC, fibrin, or nothing (empty conduit). In another study, nerve was transected and either left undisturbed or wrapped with HA/CMC around the proximal and distal ends. In a final study, nerve was transected and repaired with an HA/CMC wrap. Four weeks following the procedures, nerves were harvested and assessed using histomorphometry to measure axonal regeneration. Axonal regeneration following transection was significantly inhibited by direct axonal contact with HA/CMC, whether within a conduit or wrapped around the transected proximal nerve end. Axonal regeneration following epineurial repair was not affected by HA/CMC wrapped around nerve, demonstrating axonal growth inhibition due to direct contact of regenerating axons with HA/CMC. These studies demonstrate the efficacy of HA/CMC to limit axonal outgrowth by contact with regenerating axons. HA/CMC barriers may prove to be a tool to prevent neuroma formation by inhibiting axonal growth.