Abstract
Background Collagen and human amniotic membrane (hAM) are Food and Drug Administration (FDA)-approved
biomaterials that can be used as nerve wraps or conduits for repair of peripheral
nerve injuries. Both biomaterials have been shown to reduce scarring and fibrosis
of injured peripheral nerves. However, comparative advantages and disadvantages have
not been definitively shown in the literature. The purpose of this systematic review
is to comprehensively evaluate the literature regarding the roles of hAM and collagen
nerve wraps and conduits on peripheral nerve regeneration in preclinical models.
Methods The MEDLINE database was queried using the PubMed search engine on July 7, 2019,
with the following search strategy: (“amniotic membrane” OR “amnion”) OR (“collagen
conduit” OR “nerve wrap”)] AND “nerve.” All resulting articles were screened by two
independent reviewers. Nerve type, lesion type/injury model, repair type, treatment,
and outcomes were assessed.
Results Two hundred and fifty-eight articles were identified, and 44 studies remained after
application of inclusion and exclusion criteria. Seventeen studies utilized hAM, whereas
27 studies utilized collagen wraps or conduits. Twenty-three (85%) of the collagen
studies utilized conduits, and four (15%) utilized wraps. Six (35%) of the hAM studies
utilized conduits and 11 (65%) utilized wraps. Two (9%) collagen studies involving
a conduit and one (25%) involving a wrap demonstrated at least one significant improvement
in outcomes compared with a control. While none of the hAM conduit studies showed
significant improvements, eight (73%) of the studies investigating hAM wraps showed
at least one significant improvement in outcomes.
Conclusion The majority of studies reported positive outcomes, indicating that collagen and
hAM nerve wraps and conduits both have the potential to enhance peripheral nerve regeneration.
However, relatively few studies reported significant findings, except for studies
evaluating hAM wraps. Preclinical models may help guide clinical practice regarding
applications of these biomaterials in peripheral nerve repair.
Keywords peripheral nerve - microsurgery - biomaterials
