Bridging the neural gap.

A major limitation to overall success in peripheral nerve surgery is time for regeneration. Although one can help speed up the regenerative process to some extent, success is hindered by issues such as number of coaptation sites, supply of donor nerves, and the limitations of nerve substitutes. In the case of a large gap, a nerve graft is often used to fill in the deficit. Autogenous nerve grafts are in limited supply, with sural nerve grafts being the primary source. Alternatives to the standard treatment include vein grafts, synthetic nerve conduits, nerve transfers, and nerve transplantation. Schwann cell-lined nerve conduits and tissue-engineered substitutions are still in their infancy and have some limited clinical application.