Nerve grafting for peripheral nerve injuries with extended defect sizes

Artificial and non-artificial nerve grafts are the gold standard in peripheral nerve reconstruction in cases with extensive loss of nerve tissue, particularly where adirect end-to-end suture or an autologous nerve graft is inauspicious. Different materials are marketed and approved by the US Food and Drug Administration (FDA) for peripheral nerve graft reconstruction. The most frequently used materials are collagen and poly(DL-lactide-epsilon-caprolactone). Only one human nerve allograft is listed for peripheral nerve reconstruction by the FDA. All marketed nerve grafts are able to demonstrate sufficient nerve regeneration over small distances not exceeding 3.0cm. Akey question in the field is whether nerve reconstruction on large defect lengths extending 4.0cm or more is possible. This review gives asummary of current clinical and experimental approaches in peripheral nerve surgery using artificial and non-artificial nerve grafts in short and long distance nerve defects. Strategies to extend nerve graft lengths for long nerve defects, such as enhancing axonal regeneration, include the additional application of Schwann cells, mesenchymal stem cells or supporting co-factors like growth factors on defect sizes between 4.0 and 8.0cm. ZusammenfassungDer Goldstandard in der Versorgung von peripheren Nervendefekten ist nach wie vor die autologe Transplantation. Sollte eine Versorgung des Defekts mittels eines autologen Transplantats nicht moglich sein, so gibt es die Moglichkeit, auf von der U.S. Food and Drug Administration (FDA) zugelassene kunstliche Nervenimplantate zuruckzugreifen. Diese sind jedoch nur fur periphere Nervendefekte <3,0cm erprobt und zugelassen, fur Defekte, welche diese 3,0cm ubersteigen, gibt es derzeit keine zugelassenen Alternativen. Fur durch Tumorinfiltration oder Trauma entstehende Defekte werden diese aber dringend benotigt. Der Reviewartikel gibt einen uberblick uber aktuelle Forschungsansatze mit dem Ziel der Transplantatversorgung langstreckiger Nervendefekte und zeigt die Notwendigkeit neuer, innovativer Forschungsansatze auch im Bereich der autologen Zelltransplantation.