A Human Hair Keratin Hydrogel Scaffold Enhances Median Nerve Regeneration in Nonhuman Primates: An Electrophysiological and Histological Study

Address correspondence to: Mark Van Dyke, PhD, Virginia Tech-Wake Forest School of Biomedical Engineering and Sciences (SBES) Virginia Polytechnic Institute and State University, 226 ICTAS II (0917) Blacksburg, VA 24061, E-mail: [email protected]

Introduction

Nerve injury of the upper extremity occurs most frequently in young males as a result of motor vehicle collision. These injuries can result in permanent disability and diminished quality of life.^1-3 Techniques for surgical management of peripheral nerve transection injuries vary depending on injury severity, although primary end-to-end neurorrhaphy is the preferred treatment. If primary repair cannot be performed due to severe local tissue trauma or retraction of the distal or proximal nerve stumps, a graft may be interposed between the two nerve ends to attain a tension-free repair.⁴ Autologous nerve grafts, most commonly harvested from the sural nerve, have long been considered the gold standard for peripheral nerve repair, although they require extensive microsurgical skills as they are technically challenging, and result in increased surgical time and donor-site morbidity.⁵

Alternatives to autograft are currently under investigation in both preclinical studies and clinical trials.^6,7 Hollow tubes, referred to as nerve guides or nerve conduits, constructed of collagen type I (NeuraGen, Neuroflex(TM), and NeuroMatrix(TM)), polycaprolactone (Neurolac^® ), and polyglycolic acid (Neurotube^® ) are available for clinical use. The advantage of nerve conduits is their relative...