Efficacy of Nerve Tape-Assisted PEG Fusion in a Rabbit Tibial Nerve Repair Model.

Abstract

Background: Polyethylene glycol (PEG) hydrogel is capable of fusing transected axons and restoring axonal continuity. The technique requires precise nerve coaptation alignment and stability, which is difficult to achieve utilizing conventional microsuture neurorrhaphy. Nerve Tape (NT) is a microhook-based nerve coaptation device engineered to facilitate stable and accurate nerve end alignment. The primary objective was to modify and validate NT-assisted PEG fusion using a rabbit proximal tibial nerve repair model at an intermediate time point.

Methods: Three groups of rabbits underwent mid-thigh tibial nerve transection and immediate repair with NT + PEG (n = 6), Suture + PEG (n = 6), or Suture only (n = 6). PEG-induced axonal fusion was acutely confirmed via demonstration of compound motor action potential (CMAP) restoration. Final outcome testing at 16 weeks included electrodiagnostic testing, nerve histomorphology, and muscle morphology.

Results: All 18 animals demonstrated immediate restoration of CMAPs. At 16 weeks, there were no statistical differences in nerve conduction velocity or amplitude, no statistical differences between groups in axon counts or g-ratios either near the nerve coaptations or at the ankle, and no differences in normalized gastrocnemius weight or girth.

Conclusion: PEG fusion did not improve nerve regeneration or functional recovery in a rabbit tibial nerve repair model at 16 weeks. Modified NT did not improve the reliability or efficacy of the PEG fusion process compared with microsuture neurorrhaphy.