Regeneration and repair of peripheral nerves.

Posttraumatic nerve repair continues to be a major challenge in restorative medicine and microsurgery. Although progress has been made in surgical techniques over the last 30 years, functional recovery after a severe lesion of a major nerve trunk is often incomplete and often unsatisfactory. Functional recovery after surgical repair of mixed nerves is even more disappointing. Functional recovery after peripheral nerve lesion is dependent upon accurate regeneration of axons to their original target tissues. Thus, in order to enhance regeneration, a better understanding of the cellular and molecular biology of selective nerve regeneration is required. Schwann cells and their endoneurial extracellular matrix play pivotal roles in the selective promotion of motor and sensory axon regeneration. Knowledge of these mechanisms allows for the better development of biocompatible nerve grafting material.