Systematic Review of Nerve Adhesion Barriers for Peripheral Nerve Regeneration and Functional Recovery.

Background: Peripheral nerve injury (PNI) is characterized by poor functional outcomes, insufficient nerve regeneration, and deterioration of sensory and motor function. Factors such as nerve tissue loss and extended denervation of proximal nerves impede regeneration. Therapeutic interventions include microsurgical techniques and nerve-guide conduits. However, nerve adhesion, which restricts nerve mobility, also contributes to inadequate healing. Surgical modifications and chemical agents are used to mitigate adhesion.

Methods: We searched across four databases, PubMed, Cochrane Database of Systematic Reviews, EMBASE, and Medline, using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. The study quality and risk of bias were assessed using the systematic review center for laboratory animal experimentation (SYRCLE)'s and Cochrane RoB-2 tools.

Results: Out of 549 studies, 5 studies met our inclusion criteria, consisting of four animal studies and one randomized controlled trial involving human participants. Different nerve adhesion materials were evaluated in the studies included. Histological evaluation of nerve regeneration generally shows more advanced regenerative hallmarks in the intervention group. Additionally, in terms of motor and sensory function, improvements were seen in the majority of parameters observed in all studies included.

Conclusion: This systematic review indicates that nerve adhesion barriers show promising outcomes in promoting nerve regeneration and functional recovery by reducing adhesion and enhancing structural alignment in peripheral nerve injuries. Applicability of such barriers in humans may still be debatable as findings are limited by the small number of included studies and predominance of animal data. Further long-term trials may warrant its' clinical efficacy.