Peroneal Nerve Regeneration Using a Unique Bilayer Polyurethane-collagen Guide Conduit

Abstract
Unique double layer polyurethane (PU)-collagen nerve guide conduits with desirable biocompatibility and mechanical properties were fabricated using a newly developed double-nozzle low-temperature deposition manufacturing (DLDM) technique. The inner collagen layer of the conduit had oriented nano-size filaments with micro-pores (pore size 20—100μm) that permitted nutrient infiltration, while the outer PU layer had micro-pores (pore size 15—20 μm) preventing fibrous tissue invasion. In vivo animal tests (n = 6) on bridging a 10 mm long peroneal nerve defect was conducted using rats. Single layer pure PU conduit (n = 6) was used as the positive control and the same size defect with no implantation (n = 2) as the negative control. Through walk track analysis as well as electrophysiological and histological evaluations of the regenerated nerves, the double layer PU-collagen conduit demonstrated better nerve repair than the controls. This new PU-collagen has the potential for significant clinical applications in peripheral nerve repair.