The Role of Stem Cells in Peripheral Nerve Regeneration: A Narrative Review.

Stem cell therapies are gaining attention as a potential strategy for promoting recovery in peripheral nerve injuries. These injuries, particularly in complex anatomical regions, often lead to long-term functional deficits. There is a pressing need to explore novel therapeutic approaches. Experimental studies have shown that various stem cell types possess regenerative capabilities. This review synthesizes existing experimental and clinical evidence, highlighting the types of stem cells investigated, their mechanisms of action, and reported functional outcomes. Among them, adipose-derived and bone marrow-derived mesenchymal stem cells have demonstrated consistent improvements in nerve function and structural repair. Other cell types, including hair follicle and dental pulp stem cells, have also shown promising outcomes in preclinical models. Clinical studies remain limited, with only a few reporting partial recovery and minimal adverse effects. However, the overall quality of clinical evidence is low, limiting the strength of conclusions. The current evidence suggests potential, but it remains insufficient for broad clinical application. The review identifies key knowledge gaps, such as limited large-scale human trials, and underscores the need for high-quality research to determine the safety, efficacy, and feasibility of stem cell-based therapies for peripheral nerve repair. Further high-quality human trials are urgently needed to establish the safety and efficacy of these therapies.