腰椎后路手术对硬膜囊容量和脊柱稳定性的影响

目的 :进一步了解腰椎后路手术对脊柱功能的影响 ,为临床合理选择术式提供依据。方法 :采用平行光三维测量系统 ,对 12具人新鲜尸体腰椎实施全椎板切除、半椎板切除及交叉半椎板切除 ,对其屈伸状态下硬膜囊容量和脊柱稳定性的定量变化结果进行双因素方差分析。结果 :腰椎屈曲活动时硬膜囊容量增大 ,仰伸位变小 ;全椎板切除与交叉半椎板切除 ,硬膜囊容量改变相近 ,但均较半椎板切除明显增大 (P <0 0 1) ;任何一种腰椎后路手术 ,均能破坏腰椎稳定性 ,其中半椎板切除与交叉半椎板切除破坏性较小 ,而与全椎板切除相比较 ,后者破坏性大于前二者 (P <0 0 1)。结论 :下腰椎疾病后路手术应尽量保留棘突及其韧带 ,交叉半椎板切除可使椎管得到充分减压 ,同时又较好地保留脊柱的稳定性

Effects of posterior approaches on lumbar stability and spinal dural sac volume

Objective:To further understand the effects of lumbar spine on the posterior approaches,and to provide the base for rationally choosing the methods of decompression.Method:A two-way ANOVA of the spinal canal volume and spinal stability,in 12 cadavers,after performing three kinds of posterior spinal operation with the paralleled light beam measurement system for three-dimensional motion.Result:The volume of lumbar spinal canal would increase with the spinal flexion and decrease with its extension after three operations.Although total laminectomy and cross-semi-laminectomy was similar in the change of spinal canal volume with the spinal motion,they got much more volume than that in semilaminectomy (P<0.01).The change of spinal stability after three kinds of spinal posterior operation indicated that any surgical therapy could damage the stability of spine column.But semilaminectomy and cross-semi-laminectomy could damage less than total laminectomy in the stability of spinal column.Conclusion:The above findings demonstrates that both more spinal canal volume and more spinal stability can be maintained after cross-semi-laminectomy.During surgery,the posterior structures should be preserved as much as possible so as to maintain the stability of the lumbar spine.The authors recommend the advanced paralleled light technique to measure the spinal column stability in mechanical test.