Amjadi Kashani Mohammad Reza, Nikkhoo Mohammad, Khalaf Kinda, Firoozbakhsh Keikhosrow, Arjmand Navid, Razmjoo Arash, Parnianpour Mohamad
Department of Mechanical Engineering, Sharif University of Technology, Tehran, Iran
Department of Biomedical Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran Institute of Biomedical Engineering, College of Medicine and Engineering, National Taiwan University, Taipei, Taiwan.
Proc Inst Mech Eng H. 2014 Dec;228(12):1281-95. doi: 10.1177/0954411914563363.
Osteoporosis is a progressive bone disease characterized by deterioration in the quantity and quality of bone, leading to inferior mechanical properties and an increased risk of fracture. Current assessment of osteoporosis is typically based on bone densitometry tools such as Quantitative Computed Tomography (QCT) and Dual Energy X-ray absorptiometry (DEXA). These assessment modalities mainly rely on estimating the bone mineral density (BMD). Hence present densitometry tools describe only the deterioration of the quantity of bone associated with the disease and not the affected morphology or microstructural changes, resulting in potential incomplete assessment, many undetected patients, and unexplained fractures. In this study, an in-silico parametric model of vertebral trabecular bone incorporating both material and microstructural parameters was developed towards the accurate assessment of osteoporosis and the consequent risk of bone fracture. The model confirms that the mechanical properties such as strength and stiffness of vertebral trabecular tissue are highly influenced by material properties as well as morphology characteristics such as connectivity, which reflects the quality of connected inter-trabecular parts. The FE cellular solid model presented here provides a holistic approach that incorporates both material and microstructural elements associated with the degenerative process, and hence has the potential to provide clinical practitioners and researchers with more accurate assessment method for the degenerative changes leading to inferior mechanical properties and increased fracture risk associated with age and/or disease such as Osteoporosis.
骨质疏松症是一种进行性骨骼疾病，其特征是骨量和骨质量下降，导致力学性能变差和骨折风险增加。目前对骨质疏松症的评估通常基于骨密度测量工具，如定量计算机断层扫描（QCT）和双能X线吸收法（DEXA）。这些评估方式主要依靠估算骨矿物质密度（BMD）。因此，目前的密度测量工具仅描述了与该疾病相关的骨量下降情况，而没有描述受影响的形态或微观结构变化，从而导致潜在的评估不完整、许多未被检测出的患者以及无法解释的骨折。在本研究中，开发了一种包含材料和微观结构参数的椎体小梁骨计算机模拟参数模型，以准确评估骨质疏松症及随之而来的骨折风险。该模型证实，椎体小梁组织的强度和刚度等力学性能受材料特性以及连通性等形态特征的高度影响，连通性反映了小梁间连接部分的质量。这里提出的有限元细胞固体模型提供了一种整体方法，该方法纳入了与退变过程相关的材料和微观结构要素，因此有潜力为临床医生和研究人员提供更准确的评估方法，用于评估导致力学性能变差以及与年龄和/或疾病（如骨质疏松症）相关的骨折风险增加的退变变化。
