Ultrasound-guided platelet-rich plasma injection for peripheral nerve injury: a retrospective exploratory study

Although experimental studies have demonstrated that platelet-rich plasma (PRP) promotes peripheral nerve repair, its clinical efficacy in treating peripheral nerve injuries remains unclear. The present study aims to evaluate safety and functional outcomes of ultrasound-guided PRP injection for peripheral nerve injury. This retrospective study analyzed consecutive patients receiving ultrasound-guided PRP injections for peripheral nerve injuries between January 2021 and March 2025. Outcomes were assessed at 1, 3, and 6 months post-treatment, defined as: (1) a ≥2-point reduction in the Numerical Rating Scale (NRS) for sensory recovery, and (2) a ≥1-grade improvement in the Medical Research Council (MRC) scale for motor function. Patients were divided based on symptom duration into short-duration (<1 year) and long-duration (≥1 year) groups. All procedure-related complications were recorded. Among 48 treated nerves, PRP therapy resulted in gradual functional improvement and was well-tolerated. Sensory recovery rates remained stable (70.8% at 1 month to 68.8% at 6 months), while motor function improved gradually (from 50.0% to 69.4%). In an exploratory subgroup analysis, the short-duration group (n = 25) showed numerically higher rates than the long-duration group (n = 23) at 6 months (sensory: 80.0% vs. 56.5%, p = 0.08; motor: 85.0% vs. 50.0%, p = 0.034). However, after Bonferroni correction for multiple comparisons (corrected α = 0.0167), the motor improvement did not remain statistically significant. No severe adverse events occurred. The present study suggests that ultrasound-guided PRP injection appears safe and may be associated with functional improvement. The observed subgroup findings are hypothesis-generating and require confirmation in prospective randomized controlled trials.