健侧骶神经根移位修复大鼠骶丛撕脱伤

Repair of sacral plexus root avulsion with normal sacral nerve root transposition in rats

目的探讨采用健侧骶神经根移位修复骶丛撕脱伤的可行性。方法选用体重200～300g的成年sD大鼠30只，随机分为不吻合组、健侧L6-患侧L6吻合组和健侧L6-患侧L5吻合组，每组10只。大鼠右侧为实验侧，左侧为对照侧。术后观察各组大鼠的存活情况，对受试大鼠进行BBB评分。双侧股二头肌、小腿三头肌及胫骨前肌称重并进行肌肉横截面HE染色的对比研究；电镜观察吻合口远端神经生长情况；坐骨神经功能指数（SFI）、肌电图检查评价吻合的可行性。结果术后12周吻合组BBB评分比不吻合组高（P〈0．01）。吻合组右侧的股二头肌、小腿三头肌、胫前肌与不吻合组相比均有不同程度恢复。其中L6-L5吻合组效果较L6-L6吻合组好。三组肌群恢复速度在L6-L6吻合组内有差异，其中近侧股二头肌恢复效果相对较好，吻合口远端神经电镜观察可见大量再生有髓神经纤维。肌电图显示于三组肌肉可记录到波幅，其中以近侧股二头肌及小腿三头肌峰值较大，远侧胫前肌峰值较小。结论健侧骶神经根移位加自体神经移植或健侧骶神经移位与患侧神经根直接吻合均能重建截瘫大鼠骶丛神经的部分功能，其中健侧骶神经移位与患侧神经根直接吻合组效果优于健侧骶神经根移位加自体神经移植组。

Objective To evaluate the efficiency of normal sacral nerve root transposition in repair of the sacral plexus root avulsion. Methods A total of 30 adult SD rats were chosen and divided into three groups, ie, group A （the sciatic nerve received no repair） , group B （the autologous sacral plexus root nerve was bridged with the right L6 nerve root by the translocation of the left L6 ） and group C （ the right L5 nerve root nerve was bridged by the translocation of the left L6 ） , 10 rats per group. The left side of the rats was used as the control side and the right one as the experimental side. Twelve weeks after operation, the rats in each group were selected for the histomorphological observation of the nerves under the microscope and the electron microscope. The models were evaluated by observing the survival rates of the rats, BBB scores, electron microscope weight and muscle fiber CSA（cross section area） of double biceps femoris, triceps surae and tibial muscle. Results Twelve weeks after operation, the BBB scores in groups B and C was higher than that in group A, with statistical difference （P 〈0.01 ） between three groups. A remarkable improvement was found in the ratio of weight and muscle fiber CSA of double biceps femoris, triceps surae and tibial muscle. The repair efficiency in the group C was better than that in the group B. In the group B, the biceps femoris, triceps surae and tibial muscle recovered at different degrees. The biceps femoris recovered the best, when a great deal of myelinated nerve fiber regeneration was observed under the microscope and the electromicroscope. Electromyography revealed the volatility in the muscles of three groups, with larger peak value for the proximal biceps femoris and the triceps muscle but smaller peak value for the distal anterior tibial muscle. Conclusions L6 transposition combined with auto-graft of nerve root or without the auto-graft can reconstruct the partial function of the sciatic nerve in the paraplegia rats, when the latter has the better effect.