膈神经移位修复臂丛神经下干后股重建伸趾功能的实验研究

Experimental study of innervation of the posterior division of the lower trunk with phrenic nerve for restoration of toe extension

目的明确动力神经移位到下干后股可否恢复大鼠伸趾功能。方法取健康雌性SD大鼠6只，对下干后股和桡神经深支进行荧光染色，观察两者在脊髓内分布情况。再取12只SD健康雌性大鼠分为2组，每组6只。移位组：将膈神经通过神经移植移位到下干后股。直接缝合组：切断下干后股直接缝合。于术后3个月行大体观察、电生理和肌肉检测。结果下干后股和桡神经深支在颈。胸，节段均有染色阳性细胞，前者较后者多。移位组大鼠均于术后31～38d出现与呼吸同步的伸趾动作。电生理和肌肉检测显示，二组大鼠尺侧腕伸肌、趾总伸肌和肱三头肌内侧头都有不同程度的恢复，但直接缝合组优于移位组，差异有统计学意义（P〈0．05）。结论将动力神经移位到下干后股可以部分恢复大鼠伸趾功能。

Objective To evaluate the efficacy of nerve transfer to the posterior division of the lower trunk for restoration of toe extension in rats. Methods Retrograde tracing of the posterior division of the lower tnmk and deep branch of the radial nerve with fluorescence was carried out in 6 healthy female Sprague-Dawley rats. Another 12 female SD rats were randomly divided into 2 groups： transfer group and direct coaptation group, with 6 each. In the transfer group the phrenic nerve was transferred to the posterior division of the lower trunk with a nerve graft. In the direct coaptation group the posterior division of the lower tnmk was transected and sutured directly. Gross observation, electrophysiological testing and muscle examination were performed 3 months after the operation. Results Both the posterior division of the lower tnmk and deep branch of the radial nerve had fluorescence labeled neurons in the anterior horn of the spinal cord at CsT1 level. The former had more labeled neurons than the latter. In transfer group toe extension appeared at postoperative day 31 to 38 that was synchronized with respiration. Electrophysiology and muscle observation showed recovery of extensor carpi ulnaris, extensor digitomm communis and medial head of the triceps in both groups. Recovery in the direct coaptation group was significantly better than that in the transfer group （ P 〈 0.05）. Conclusion Toe extension can be partially restored nerve transfer to the posterior division of the lower trunk.