摘要
目的 探讨肢体缓慢牵伸延长周围神经亚临床损伤的自然修复过程。方法 6 2只日本大耳白兔胫骨延长至 40 % ,停止延长后 2周、4周、8周时观察胫神经损伤自然修复的组织学及感觉诱发电位 (CSEP)的改变。结果 延长 40 %时 ,可见广泛的节段性脱髓鞘 ,朗飞氏结区增宽 ,且主要发生于大的有髓神经纤维 ;电镜下可见髓鞘呈双环状 ,空泡状改变及环形小体形成压迫轴突 ;并可见新形成的髓鞘 ;停止延长后随着时间的延长 ,这种改变逐渐修复 ;至 8周时基本恢复正常。肢体延长造成了胫后神经明显的电生理损害 ,且随着延长幅度的增加而加剧。停止延长后 2周 ,CSEP的潜伏期恢复约 5 0 %。停止延长 4周恢复约 6 5 % ,峰值、面积亦恢复约 5 0 %。停止延长 8周 ,各项指标均恢复 95 %以上。结论 缓慢牵伸下肢延长过程中周围神经的损害是可逆的 。
Objective To study the repairing process of the peripheral nerves after gradual traction lengthening of the tibia in rabbits.Methods The tibia of one hind leg of 62 Japanese large ear rabbits was lengthened by 40% with gradual traction. The histological and ultrastructural changes and the changes of cortical sensory evoked potentials (CSEP) were observed with optical and electron microscopies and Nicolet Viking Ⅳ electrophysiological instrument 2, 4 and 8 weeks after the cessation of tibial lengthening respectively.Result Optical microscopy revealed extensive segmental demyelination mainly in big myelinated nerve fibers. Electron microspocy showed that the myelin sheath was in double ring shape with vacuolization and formation of ring shaped body which pressed on axons. Newly formed myelin sheath could be seen. After the cessation of lengthening, these changes gradually recovered and normality was restored 8 weeks after lengthening cessation.The electrophysiological changes were intensified along with the lengthening of the tibia. The latency of CSEP was recovered by 50% 2 weeks after the cessation of tibial lengthening and by 65% 4 weeks after. In the 4th week after cessation of lengthening, 50% recovery of the amplitude peak and area of CSEP was also observed. In the 8th week after stopping lengthening, CSEP restored 95% of its normal function.Conclusion The subclinical damages of the peripheral nerves resulting from tibial lengthening are temporary and reversible.
出处
《第三军医大学学报》
CAS
CSCD
北大核心
2000年第5期470-473,共4页
Journal of Third Military Medical University
关键词
肢体延长
周围神经亚临床损害
修复
兔
limb lengthening
tibial nerve
subclinical damage
repair
rabbit
