腰椎管狭窄症马尾神经冗余征的观察及临床意义

目的　观察腰椎管狭窄症马尾神经冗余征（redundant nerve roots, RNRs）的形态,了解RNRs与节段椎管狭窄的关系,探讨RNRs的临床意义。 方法　2016年1月至2016年11月我院收治的单节段腰椎管狭窄症患者134例,行仰卧位MRI检查,观察矢状位椎管内马尾神经走行及形态,分为RNRs（+）和RNRs（-）,并测量狭窄节段椎管正中矢状径、有效矢状径、椎管有效截面积,统计学比较分析RNRs（+）与狭窄节段狭窄程度的关系。 结果　134例腰椎管狭窄症患者,男61例,女73例,年龄24～80岁（平均54.4±13.6岁）,RNRs（+）43例,RNRs（-）91例,RNRs形态分为“藤索”型29例(67.44%,29/43),“葡萄串珠”型6例(13.95％,6／43),“蛇纹石”型8例(18.60%,8/43)。RNRs（+）组椎管有效截面积明显小于RNRs（-）组,具有显著统计学意义(P<0.05);但两组之间正中矢状径、有效矢状径比较, 无统计学差异(P>0.05)。 结论　马尾神经冗余征见于严重腰椎管狭窄症患者,其发生与椎管绝对性狭窄有关,可作为腰椎管狭窄症手术指征之一。

The observation and clinical significance of redundant nerve roots of cauda equina in lumbar spinal stenosis

Objective　To observe the morphology of Redundant Nerve Roots（RNRs）of cauda equina in lumbar spinal stenosis and to discuss the clinical significance of RNRs.　Methods　From January to November 2016, 134 patients with single segmental lumbar spinal stenosis were treated in our hospital and received routine MRI scan. Based on sagittal MRI, cauda equina can be divided into RNRs（+）and RNRs（-）. The median sagittal diameter, the effective sagittal diameter and the effective cross-sectional canal area of the stenotic segment of spinal canal were measured. The relationship between RNRs（+）and the degree of stenosis was analyzed statistically. 　Results　Among 134 patients , 61 males and 73 females, aged 24~80 years (mean age 54.4±13.6 years), RNRs was positive in 43 cases, and negative in 91 cases. The RNRs（+） morphology can be divided into three types： "stripe" type in 29 cases (67.44%, 29/43), "grape beads" type in 6 cases (13.95%, 6/43), and "serpentine "type in 8 cases (18.60%, 8 / 43).The effective cross-sectional canal area in RNRs（+） group was significantly smaller than that in RNRs（-）(P<0.05), but no significant difference was found between median sagittal diameter and effective sagittal diameter in both groups (P>0.05) . Conclusion　 RNRs of cauda equina can be found in severe lumbar spinal stenosis and it is associated with absolute stenosis of the spinal canal. Therefore, it is suggested RNRs can be used as an indicator for surgical treatment of lumbar spinal stenosis.