肌外膜转位重建神经外膜的实验研究

An experimental study on the reconstruction of epineurium with pedicled epimysium flap

目的观察带蒂肌外膜瓣转位重建神经外膜后的组织学改变及其对损伤段神经再生的作用。方法将60只SD大鼠,按手术先后随机平分为实验组和对照组。建立一侧坐骨神经挤压伤(6mm长)模型。伤后3周行神经松解术,2组均切除损伤处神经外膜1cm。实验组用带蒂肌膜瓣转位重建损伤段的神经外膜,对照组用周围正常的软组织覆盖神经损伤段。于术后42d进行大体、电生理、组织学观察和形态学分析。结果实验组重建的神经外膜表面光滑,与周围无明显粘连,神经外膜与肌膜缝合口愈合良好,外膜下血管及再生有髓神经纤维数目增加,直径增粗,运动神经传导速度(MNCV)平均达62.50m/s。对照组损伤段神经与周围组织粘连明显,MNCV均值为34.48m/s。结论肌外膜瓣重建神经外膜后其组织学改变与神经外膜极为相似,为临床应用提供了实验室依据。

Objective To observe the histological changes ot epimysium-reconstructed epineurium and investigate its role in the regeneration of the injured nerves. Methods Sixty male SD rots weighing 200 - 250 g were randomly divided into the test group and the control group, with 30 each. A standard hemostat system, described by Gudemez E, was used to create Seddon classification Ⅱ injury of the sciatic nerve with a length of 6 mm. Three weeks postoperatively, interfascicular neurolysis and removal of 1cm epincurium at the injured site were performed. Then the nearby epimysium flap was transferred to and wrapped around the epineurinm-removed segment in the test group, but not in the control group. Gross observation, electrophysiological test, histological examination and nerve morphometry were carried out 42 days after the reconstruction. Results The reconstructed epineurinm was smooth in appearance without obvious adhesion. While the injured nerve of the control group showed marked adhesion. Moreover, the test group achieved significantly faster motor nerve conductive velocity（MNCV） （ 62.50 m/s）, larger diameters and a greater number of myelinated fibers and subepineurial vessels when compared to the control group, whose MNCV was 34.48m/s. Conclusion The histological changes of the epimysium-reconstructed epineurium was similar to the intact epineurium. This suggested that the method could improve functional recovery of the injured nerves.