Polyethylene Glycol-Mediated Axonal Fusion Promotes Early Sensory Recovery after Digital Nerve Injury: A Randomized Clinical Trial.

Background: Peripheral nerve repair is limited by Wallerian degeneration coupled with the slow and inconsistent rates of nerve regrowth. In more proximal injuries, delayed nerve regeneration can cause debilitating muscle atrophy. Topical application of polyethylene glycol (PEG) during neurorrhaphy facilitates the fusion of severed axonal membranes, immediately restoring action potentials across the coaptation site. In preclinical animal models, PEG fusion resulted in remarkable early functional recovery.

Methods: This is the first randomized clinical trial comparing functional outcomes between PEG fusion and standard neurorrhaphy. Participants with digital nerve transections were followed up at 2 weeks, 1 month, and 3 months postoperatively. The primary outcome was assessed using the Medical Research Council Classification (MRCC) rating for sensory recovery at each time point. Semmes-Weinstein monofilaments and static 2-point discrimination determined MRCC ratings. Postoperative quality of life was measured using the Michigan Hand Outcomes Questionnaire.

Results: Forty-eight transected digital nerves (25 control and 23 PEG) across 22 patients were analyzed. PEG-fused nerves demonstrated significantly higher MRCC scores at 2 weeks (OR, 16.95; 95% CI, 1.79 to 160.38; P = 0.008) and 1 month (OR, 13.40; 95% CI, 1.64 to 109.77; P = 0.009). Participants in the PEG cohort also had significantly higher average Michigan Hand Outcomes Questionnaire scores at 2 weeks (Hodge g , 1.28; 95% CI, 0.23 to 2.30; P = 0.0163) and 1 month (Hodge g , 1.02; 95% CI, 0.04 to 1.99; P = 0.049). No participants had adverse events related to the study drug.

Conclusion: PEG fusion promotes early sensory recovery and improved patient well-being following peripheral nerve repair of digital nerves.

Clinical question/level of evidence: Therapeutic, II.