Abstract

Objective

To estimate the effect of the knee bolster use during an MRI on lumbar spinal stenosis parameters and low back pain-related disability.

Methods

A repeated-measurement study of 27 males and 19 females with mean age 55.78 ± 14.36, referred for an MRI of the lumbar spine due to low back pain, performed with and without standard knee bolster. A radiologist evaluated the lumbar lordosis Cobb’s angle, the cross-sectional area of the right and left intervertebral foramina and spinal canal at L1-L2, L2-L3, L3-L4 spinal levels. Spinal symptoms were evaluated by the Oswestry Disability Questionnaire.

Results

The Cobb angle of lumbar lordosis was found significantly greater on an MRI performed without knee bolster than with bolster (47.30 ± 9.90 vs. 42.57 ± 10.62, p < 0.001). The cross-sectional area of the intervertebral foramina and spinal canal at all evaluated levels was smaller when performed without knee bolster than with bolster. However, differences were significant only at the L1-L2 level and in the spinal canal at all evaluated levels. The Cobb angle, measured with and without knee bolster, showed significant positive correlations with back pain while standing and walking. The spinal canal area without knee bolster showed greater correlations with the Oswestry score parameters than with knee bolster.

Conclusions

MR images at evaluated spinal levels taken without knee bolster showed greater correlations of the spinal canal cross-sectional area with the Oswestry score than ones with knee bolster. Thus, one may prefer MR images acquired without a bolster below the knee compared to an MRI with a knee bolster.

中文翻译：

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膝枕对MR图像中腰椎管狭窄参数的影响

摘要

目的

为了评估MRI期间使用护垫对腰椎管狭窄参数和与下腰痛相关的残疾的影响。

方法

一项对27位男性和19位女性的平均年龄为55.78±14.36的重复测量研究，采用或不采用标准的膝盖支撑进行了腰背疼痛引起的腰椎MRI检查。放射科医生评估了腰椎前凸Cobb角，左右椎间孔的横截面积以及L1-L2，L2-L3，L3-L4脊柱水平的椎管。脊椎症状由Oswestry残疾问卷进行评估。

结果

在没有膝支撑的情况下进行的MRI检查发现，腰椎前凸的Cobb角明显大于有支撑的情况（47.30±9.90对42.57±10.62，p  <0.001）。在没有膝支撑的情况下，与所有支撑水平相比，椎间孔和椎管的横截面面积在所有评估水平上均较小。但是，差异仅在L1-L2水平和所有评估水平的椎管中均显着。在有和没有膝盖支撑的情况下测得的Cobb角与站立和行走时的背痛呈显着正相关。与膝支撑相比，无膝支撑的椎管面积与Oswestry评分参数的相关性更大。

结论

在没有评估膝支撑的情况下，在评估的脊柱水平上的MR图像显示，与具有膝支撑的相比，椎管横截面积与Oswestry评分的相关性更大。因此，与具有膝盖枕的MRI相比，人们可能更喜欢在膝盖下方没有枕的情况下获取的MR图像。