Zhao Kristin D, Ben-Abraham Ephraim I, Magnuson Dixon J, Camp Jon J, Berglund Lawrence J, An Kai-Nan, Bronfort Gert, Gay Ralph E
J Biomech Eng. 2016 May;138(5):054502. doi: 10.1115/1.4032995.
Spine intersegmental motion parameters and the resultant regional patterns may be useful for biomechanical classification of low back pain (LBP) as well as assessing the appropriate intervention strategy. Because of its availability and reasonable cost, two-dimensional (2D) fluoroscopy has great potential as a diagnostic and evaluative tool. However, the technique of quantifying intervertebral motion in the lumbar spine must be validated, and the sensitivity assessed. The purpose of this investigation was to (1) compare synchronous fluoroscopic and optoelectronic measures of intervertebral rotations during dynamic flexion-extension movements in vitro and (2) assess the effect of C-arm rotation to simulate off-axis patient alignment on intervertebral kinematics measures. Six cadaveric lumbar-sacrum specimens were dissected, and active marker optoelectronic sensors were rigidly attached to the bodies of L2-S1. Fluoroscopic sequences and optoelectronic kinematic data (0.15-mm linear, 0.17-0.20 deg rotational, accuracy) were obtained simultaneously. After images were obtained in a true sagittal plane, the image receptor was rotated in 5 deg increments (posterior oblique angulations) from 5 deg to 15 deg. Quantitative motion analysis (qma) software was used to determine the intersegmental rotations from the fluoroscopic images. The mean absolute rotation differences between optoelectronic values and dynamic fluoroscopic values were less than 0.5 deg for all the motion segments at each off-axis fluoroscopic rotation and were not significantly different (P > 0.05) for any of the off-axis rotations of the fluoroscope. Small misalignments of the lumbar spine relative to the fluoroscope did not introduce measurement variation in relative segmental rotations greater than that observed when the spine and fluoroscope were perpendicular to each other, suggesting that fluoroscopic measures of relative segmental rotation during flexion-extension are likely robust, even when patient alignment is not perfect.
脊柱节段间运动参数及由此产生的区域模式可能有助于对下腰痛（LBP）进行生物力学分类以及评估合适的干预策略。由于其可用性和合理的成本，二维（2D）荧光透视法作为一种诊断和评估工具具有巨大潜力。然而，量化腰椎椎间运动的技术必须经过验证，并评估其敏感性。本研究的目的是：（1）在体外动态屈伸运动期间比较同步荧光透视法和光电测量法对椎间旋转的测量结果；（2）评估C形臂旋转以模拟患者非轴向对齐对椎间运动学测量的影响。解剖了六个尸体腰骶标本，并将有源标记光电传感器牢固地附着于L2 - S1椎体。同时获取荧光透视序列和光电运动学数据（线性精度为0.15毫米，旋转精度为0.17 - 0.20度）。在真正的矢状面获取图像后，将图像接收器以5度增量（后斜角）从5度旋转至15度。使用定量运动分析（qma）软件从荧光透视图像中确定节段间旋转。在每次荧光透视非轴向旋转时，所有运动节段的光电值与动态荧光透视值之间的平均绝对旋转差异均小于0.5度，并且对于荧光透视仪的任何非轴向旋转，差异均无统计学意义（P > 0.05）。腰椎相对于荧光透视仪的小错位不会导致相对节段旋转的测量变化大于脊柱与荧光透视仪相互垂直时观察到的变化，这表明即使患者对齐不完美，屈伸过程中相对节段旋转的荧光透视测量可能也很可靠。
