Polyethylene-Glycol Assisted Neurorrhaphy Promotes Superior Functional Recovery Following Injury of Mixed Nerves in the Upper Extremities

Introduction: In proximal injuries of mixed sensory-motor nerves, delayed nerve regeneration can cause debilitating muscle atrophy. Topical application of polyethylene glycol (PEG) during neurorrhaphy prevents Wallerian degeneration and has been shown to accelerate functional recovery in animals. Currently, there are no human studies on PEG-fusion in mixed sensory-motor nerve injuries. Methods: This study compares patients treated with PEG with demographically matched historical controls previously treated at our institution. Patients with median or ulnar nerves injuries were treated with our novel PEG-fusion protocol. Participants followed up at 2 weeks, 1 month, 3 months, 6 months, and 1 year postoperatively. Sensory recovery was assessed at each timepoint using Semmes-Weinstein monofilaments and static two-point discrimination. Medical Research Council Classification (MRCC) scores for sensory and motor recovery were calculated using sensory assessments and blinded clinician assessment. Results: A total of 18 patients (6 PEG, 12 control) with a total of 20 transected nerves (10 median, 10 ulnar) were analyzed. Patients treated with PEG demonstrated significantly greater sensation at 2 weeks (p < 0.000), 1 month (p < 0.000), 3 months (p < 0.000), 6 months (p < 0.000), and 1 year (p = 0.028) compared to historical controls. Patients in both cohorts demonstrated similar MRCC motor scores in the early postoperative period, however at 1 year postoperatively PEG patients significantly outperformed their control counterparts in motor function (p < 0.000). Conclusion: PEG-fusion accelerates sensory recovery following the repair of a mixed sensory-motor nerve and allows for superior motor function later in recovery.