Sandoz Baptiste, Laporte Sébastien, Skalli Wafa, Mitton David
CNRS, Arts et Metiers ParisTech, 151 bd de l’Hopital, Paris, France.
Comput Methods Biomech Biomed Engin. 2010 Dec;13(6):649-54. doi: 10.1080/10255841003717608.
In order to improve the reliability of children's models, the aim of this study was to determine the subject-specific masses and 3D locations of the centres of mass (CoM) of body segments using biplanar X-rays. Previous methods, validated on upper leg segments, were applied to the whole body. Six children and six adults were studied. The low-dose X-ray system EOS(®) was used to simultaneously get head-to-foot biplanar X-rays in the upright position. Specific methods were used to get 3D reconstructions of bones and body shape. The densities from the literature were used to define the masses. To assess the accuracy of the reconstructions, a force plate was used to compare the mass and the projection of the CoM. A mean distance of 4.5 mm between the measured and the calculated projections of the CoM was found. The mean error between the estimated and the actual body mass was 2.6%. Such a method will be useful in obtaining the body segment parameters in children, hard to obtain using direct measurement techniques.
为提高儿童模型的可靠性，本研究旨在利用双平面X射线确定身体各节段的个体特异性质量和质心（CoM）的三维位置。先前在上腿部节段验证过的方法应用于全身。研究了6名儿童和6名成人。使用低剂量X射线系统EOS(®)在直立位同时获取从头到脚的双平面X射线。采用特定方法对骨骼和身体形状进行三维重建。利用文献中的密度来定义质量。为评估重建的准确性，使用测力板比较质量和质心的投影。发现质心的测量投影与计算投影之间的平均距离为4.5毫米。估计体重与实际体重之间的平均误差为2.6%。这种方法将有助于获取儿童的身体节段参数，而这些参数很难用直接测量技术获得。
