Gray Hans A, Guan Shanyuanye, Pandy Marcus G
Department of Mechanical Engineering, University of Melbourne, Victoria 3010, Australia.
Department of Mechanical Engineering, University of Melbourne, Victoria 3010, Australia.
J Biomech. 2017 May 24;57:152-156. doi: 10.1016/j.jbiomech.2017.04.009. Epub 2017 Apr 19.
The aim of this study was to evaluate the accuracy with which mobile biplane X-ray imaging can be used to measure patellofemoral kinematics of the intact knee during overground gait. A unique mobile X-ray imaging system tracked and recorded biplane fluoroscopic images of two human cadaver knees during simulated overground walking at a speed of 0.7m/s. Six-degree-of-freedom patellofemoral kinematics were calculated using a bone volumetric model-based method and the results then compared against those derived from a gold-standard bead-based method. RMS errors for patellar anterior translation, superior translation and lateral shift were 0.19mm, 0.34mm and 0.37mm, respectively. RMS errors for patellar flexion, lateral tilt and lateral rotation were 1.08°, 1.15° and 1.46°, respectively. The maximum RMS error for patellofemoral translations was approximately one-half that reported previously for tibiofemoral translations using the same mobile X-ray imaging system while the maximum RMS error for patellofemoral rotations was nearly two times larger than corresponding errors reported for tibiofemoral rotations. The lower accuracy in measuring patellofemoral rotational motion is likely explained by the symmetric nature of the patellar geometry and the smaller size of the patella compared to the tibia.
本研究的目的是评估在地面行走过程中，移动双平面X射线成像用于测量完整膝关节髌股关节运动学的准确性。一个独特的移动X射线成像系统在模拟地面行走过程中，以0.7m/s的速度跟踪并记录了两具人类尸体膝关节的双平面荧光透视图像。使用基于骨体积模型的方法计算了六自由度髌股关节运动学，然后将结果与基于金标准珠子的方法得出的结果进行比较。髌骨向前平移、向上平移和侧向移位的均方根误差分别为0.19mm、0.34mm和0.37mm。髌骨屈曲、侧向倾斜和侧向旋转的均方根误差分别为1.08°、1.15°和1.46°。髌股关节平移的最大均方根误差约为先前使用相同移动X射线成像系统报告的胫股关节平移误差的一半，而髌股关节旋转的最大均方根误差几乎比报道的胫股关节旋转相应误差大两倍。测量髌股关节旋转运动时较低的准确性可能是由髌骨几何形状的对称性以及与胫骨相比髌骨较小的尺寸所解释的。
