Nerve recovery from treatment with a vascularized nerve graft compared to an autologous non-vascularized nerve graft in animal models: A systematic review and meta-analysis

PLoS One. 2021 Dec 2;16(12):e0252250. doi: 10.1371/journal.pone.0252250. eCollection 2021.

Abstract

Background: Treatment of nerve injuries proves to be a worldwide clinical challenge. Vascularized nerve grafts are suggested to be a promising alternative for bridging a nerve gap to the current gold standard, an autologous non-vascularized nerve graft. However, there is no adequate clinical evidence for the beneficial effect of vascularized nerve grafts and they are still disputed in clinical practice.

Objective: To systematically review whether vascularized nerve grafts give a superior nerve recovery compared to non-vascularized nerve autografts regarding histological and electrophysiological outcomes in animal models.

Material and methods: PubMed and Embase were systematically searched. The inclusion criteria were as follows: 1) the study was an original full paper which presented unique data; 2) a clear comparison between a vascularized and a non-vascularized autologous nerve transfer was made; 3) the population study were animals of all genders and ages. A standardized mean difference and 95% confidence intervals for each comparison was calculated to estimate the overall effect. Subgroup analyses were conducted on graft length, species and time frames.

Results: Fourteen articles were included in this review and all were included in the meta-analyses. A vascularized nerve graft resulted in a significantly larger diameter, higher nerve conduction velocity and axonal count compared to an autologous non-vascularized nerve graft. However, during sensitivity analysis the effect on axonal count disappeared. No significant difference was observed in muscle weight.

Conclusion: Treating a nerve gap with a vascularized graft results in superior nerve recovery compared to non-vascularized nerve autografts in terms of axon count, diameter and nerve conduction velocity. No difference in muscle weight was seen. However, this conclusion needs to be taken with some caution due to the inherent limitations of this meta-analysis. We recommend future studies to be performed under conditions more closely resembling human circumstances and to use long nerve defects.

Publication types

  • Meta-Analysis
  • Research Support, Non-U.S. Gov't
  • Systematic Review

MeSH terms

  • Animals
  • Disease Models, Animal
  • Female
  • Humans
  • Male
  • Nerve Regeneration
  • Nerve Tissue* / injuries
  • Nerve Tissue* / transplantation
  • Nerve Transfer / methods*
  • Rabbits
  • Rats
  • Recovery of Function
  • Transplantation, Autologous / methods*
  • Trauma, Nervous System / therapy*

Grants and funding

The authors will receive an award from ZonMw upon publication. Partially to make open access publication possible. ZonMw is an independent institute which has no benefits from the publicated data of this article. Therefore, the funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Initials receiving author: T. De Jong Grant number: 114024159 Name funder: ZonMw URL:https://www.zonmw.nl/nl/ The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.