周围神经纵向牵拉延长的实验研究

Expermental Study of Longitudinal Stretching in Peripheral Nerve

为研究周围神经牵拉延长的可能性及有效性，进行了以下实验：（１）建立周围神经纵向牵拉延长的动物模型。选用２０只家兔，切断双侧正中神经。右侧为实验组，左侧为对照组。右侧正中神经的远端与邻近被切断肌腱的近端在同一平面牢固缝合，用银丝分别在缝接部及肱骨髁上作标记。实验侧术后每周摄片观察神经牵长的动态过程。３周后，根据Ｘ线片、神经外膜血供变化及组织学检查加以评估。结果显示：神经牵长率≥３０％，会明显增加神经纤维化程度，可能与牵长神经的血流阻滞有关。（２）选用６只神经牵长率≥２０％且被牵拉神经无明显纤维化的动物模型，切除牵长侧１０ｍｍ被牵长神经段，双侧正中神经在无张力下缝合。１２周后，采用电生理，组织学检查及超微结构等方法来检测双侧正中神经再生情况。结果显示两侧无显著性差异。结论：（１）神经牵拉延长能够修复节段性周围神经缺损；（２）神经缓慢牵拉３周且牵长率＜３０％，能有效地减少神经内纤维化；（３）可以通过牵拉神经远段进行神经延长；（４）神经牵长修复优越于其它方法修复周围神经缺损。

The purpose of this study was to determine the possibility and efficacy of nerve longitudinal stretching. Bilateral median nerves were transected in twenty rabbits. On the right side the distal end of median nerve was affixed to the proximal end of the adjacent transected tendon in the identical plane. Marks were made in the anastomotic site and humerus respectively awith thin wire. The nerves of another side were served as control. X-ray film was taken weekly after surgery in the experimental side. Three weeks later, all animals were evaluated by radiography, perineurial microcirculation and histologic studies. The result showed that length gained on the stretched side above 30% would increase the degree of intraneural fibrosis apparently ,which related to the arrest of blood flow in the stretched nerve. The nerve segments 10 mm in length of 6 animal models with the stretching rate above 20% were excised, and then the both sides were anastomosed without tension. Twelve weeks later, the bilateral median nerves were examined by electrophysiological, histological and ultrastructural methods, and there was no statistical difference between both sides. It came to the conclusions that the nerve stretching technique could be used successfully to repair segmental peripheral nerve defects, and a slow stretching of the nerve below a rate of 30% within three weeks would effectively decrease intraneural fibrosis formation. The authors considered that the nerve longitudinal stretching may be a useful alternative for nerve defect. 