Efficacy of autologous epineurium small gap coaptation combined with platelet-rich plasma, nerve growth factor, and nerve fragments in the repair of damaged peripheral nerves

Purpose: To explore the efficacy of platelet-rich plasma (PRP) combined with autologous epineurium small gap coaptation in the repair of damaged peripheral nerves. Methods: Fifty rabbits were randomly divided into five groups. The control group was treated using the traditional suture method. The remaining four groups were treated using the autologous epicardial small gap model. The autologous epithelium bridged the small gap in experimental group A, and 0.4 mL of nerve growth factor was injected into the small gap. Growth factor was administered in experimental group B, and an appropriate amount of shredded nerve fragments were added into the small gap in experimental group C. Meanwhile, 0.4 mL of PRP was injected into the small gap in experimental group D. Neuroelectrophysiological and histological assessments were performed 12 weeks after surgery. Results: The nerve conduction velocity in experimental group D was higher than in other groups. Compared to other groups, the nerves of the experimental group had small gaps, as well as no collapse or displacement. The diameter of the regenerative nerve was consistent with that of the normal nerves. In the experimental group, a higher number of myelinated nerve fibers were observed in the small gap, and the arrangement was more regular. Extensive angiogenesis was observed among the nerve fibers. More mature Schwann cells proliferated, and the cytoplasm was clear. Mitochondrial swelling was not obvious, and the epicardium and fascia were intact. Conclusion: PRP can significantly improve the microenvironment in the small gap and promote peripheral nerve regeneration and functional recovery.