Peripheral nerve regeneration by artificial nerve guides

It is more than 20 years since artificial nerve guides (or conduits) were introduced into clinical practice as a reliable alternative to autograft. They are basically cylindrical conduits inside which a regenerating nerve stump may find protection and guidance. Early guides were made of silicone and were not biodegradable; they were shown to support nerve regeneration but, subsequently, were considered responsible for stenosis of the regenerated nerve in several instances, which required their removal. Degradable guides have been proposed and are now widely used. An overview of the clinical outcome of artificial nerve guides in peripheral nerve-gap injuries has shown that they perform at least as well as autografts in gaps that are no longer than 20 mm, bringing the significant advantage of avoiding donor site sacrifice and morbidity. The present knowledge and limitations of contemporary nerve guides are illustrated; research to improve the present designs is discussed. © 2009 Springer-Verlag Milan.