Loop Nerve Graft Prefabrication In Peripheral Nerve Defect Reconstruction

Introduction

Bridging strategies are inevitable to repair nerve defects and nerve grafts are the treatment of choice in reconstruction. In this study, we prefabricated a loop nerve graft through combination of end-to-end and end-to-side coaptation methods in a staged peripheral nerve defect repair model. We investigated feasibility of improving and accelerating regeneration in conventional interpositional autologous nerve grafts with loop nerve graft prefabrication.

Material and Method

Twenty-four Sprague-Dawley rats were allocated into 3 experimental groups to evaluate regeneration in a 1.5cm long peroneal nerve defect: Single-stage conventional interpositional nerve graft (Group 1), staged loop nerve graft prefabrication (Group 2), staged conventional interpositional nerve graft (Group 3). Peroneal function index (PFI), electrophysiology and histological assessments were performed.

Results

PFI results of group 1 (-22.75±5.76) and Group 2 (-22.08±6) (p>0.05) did not show statistical difference. Group 3 presented poorest PFI value (-33.64±6.4).

Nerve conduction amplitudes for groups 1, 2 and 3 were 16.19±2.15mV, 15.95±2.82mV and 10.44±1.96mV, whereas velocity values were 1.16±0.21ms, 1.17±0.16ms and 1.51±0.15ms respectively. Electrophsiological assesments of group 1 and group 2 did not present statistical difference (p>0.05), however both groups had statistical difference compared to group 3 (p<0.05). Axon counts of group 1 (2227±260.4) and group 3 (2194±201.1) did not show difference (p>0.05). Group 2 showed highest axon count (2531±91.18).

Conclusion

Loop nerve graft prefabrication improves axonal regeneration. Loop nerve graft prefabrication in two-stages yields a favorable nerve healing, comparable to a single-stage nerve graft repair. Loop nerve graft prefabrication can be used efficiently to promote healing particularly for cases indicating a delayed nerve graft reconstruction.