Anitha D, Baum Thomas, Kirschke Jan S, Subburaj Karupppasamy
Engineering Product Development (EPD), Singapore University of Technology and Design (SUTD), Singapore
Department of Neuroradiology, Klinikum rechts der Isar, Technische Universitaet Muenchen, Muenchen, Germany
Medicine (Baltimore). 2017 Jan;96(2):e5825. doi: 10.1097/MD.0000000000005825.
The purpose of this study was to develop and validate a finite element (FE) model to predict vertebral bone strength in vitro using multidetector computed tomography (MDCT) images in multiple myeloma (MM) patients, to serve as a complementing tool to assess fracture risk. In addition, it also aims to differentiate MM patients with and without vertebral compression fractures (VCFs) by performing FE analysis on vertebra segments (T1-L5) obtained from in vivo routine MDCT imaging scans. MDCT-based FE models were developed from the in vitro vertebrae samples and were then applied to the in vivo vertebrae segments of MM patients (n = 4) after validation. Predicted fracture load using FE models correlated significantly with experimentally measured failure load (r = 0.85, P < 0.001). Interestingly, an erratic behavior was observed in patients with fractures (n = 2) and a more gradual change in FE-predicted strength values in patients without fractures (n = 2). Severe geometric deformations were also observed in models that have already attained fractures. Since BMD is not a reliable parameter for fracture risk prediction in MM subjects, it is necessary to use advanced tools such as FE analysis to predict individual fracture risk. If peaks are observed between adjacent segments in an MM patient, it can be safe to conclude that the spine is experiencing regions of structural instability. Such an FE visualization may have therapeutic consequences to prevent MM associated vertebral fractures.
本研究的目的是开发并验证一种有限元（FE）模型，以利用多排螺旋计算机断层扫描（MDCT）图像在体外预测多发性骨髓瘤（MM）患者的椎骨强度，作为评估骨折风险的补充工具。此外，它还旨在通过对从体内常规MDCT成像扫描获得的椎骨节段（T1-L5）进行有限元分析，区分有无椎体压缩骨折（VCF）的MM患者。基于MDCT的有限元模型是从体外椎骨样本开发而来的，经验证后应用于MM患者（n = 4）的体内椎骨节段。使用有限元模型预测的骨折负荷与实验测量的破坏负荷显著相关（r = 0.85，P < 0.001）。有趣的是，在骨折患者（n = 2）中观察到一种不稳定行为，而在无骨折患者（n = 2）中有限元预测的强度值变化更为平缓。在已经发生骨折的模型中也观察到了严重的几何变形。由于骨密度（BMD）不是MM患者骨折风险预测的可靠参数，因此有必要使用有限元分析等先进工具来预测个体骨折风险。如果在MM患者的相邻节段之间观察到峰值，可以有把握地得出脊柱正经历结构不稳定区域的结论。这种有限元可视化可能对预防MM相关椎体骨折具有治疗意义。
