A comprehensive review of hydrogel strategies for repairing peripheral nerve injuries

Abstract

As an etiological factor underlying physical and mental disability in humans, peripheral nerve injuries (PNIs) can induce pain, sensory impairment, and disability. Despite their regenerative ability, peripheral nerves cannot self-repair after severe defects. While nerve grafting is the gold standard for the treatment of PNIs, it is limited by graft versus host reactions, surgical complications, and limited donor nerves. As the field of material science continues to develop, hydrogels have been proposed for use in PNI repair after their biomodification, targeted modification, or loading with biological factors and cells. This article reviewed research advances in hydrogels used for PNI repair, including simple hydrogels and composite functionalized hydrogels loaded with biological factors and cells. Based on the findings from these reviews, we determined that further clarification of the mechanisms of action for hydrogels and loaded biological factors in modulating cellular functions is necessary. In addition, there is a need to further explore the synergistic effect of novel functionalized hydrogels with other biological, physical, or biochemical factors. While clinical trials are still limited, scientific efforts are expected to promote the application of hydrogels in the field of PNI repair.