Non-invasive assessment of bone strength

骨是一种具有显著适应性的组织，可以由于疾病或损伤而迅速重塑。骨的三维（3D）微观结构是理解骨力学的关键，计算机断层扫描（CT）的进步，加上定制的有限元（FE）分析方法，允许分析骨重建信号如何通过复杂结构分布。自2002年以来，我的实验室在高效和准确的计算建模方面取得了重大进展。这导致了巨大的机会，通过技术的整合和新的计算方法的发展，提高我们对骨适应机制的理解。继续我的研究计划的长期目标，下一阶段将利用新的纵向数据集来建立各种情况下骨适应的基本机制。它将结合时间序列图像数据分析和有限元建模，将骨的生物适应性与其机械和生理功能直接联系起来。新的方向还包括开发整合磁共振成像（MRI）和CT的多模态成像方法，以便探索关键生物组织（特别是软骨和骨骼）的功能相互作用。* 我的研究计划的下一阶段有三个主要目标。首先，建立一个骨骼适应的机制模型，该模型采用了以下受试者的实验纵向数据：（i）暴露于微重力下六个月（国际空间站宇航员），（ii）通过我们基于人口的研究代表正常衰老，（iii）正在接受实验治疗以增强骨骼强度。将患者特异性FE模型与测量的骨微结构局部变化相结合，为了解骨适应机制提供了独特的基础。第二，推进高通量图像处理，采用允许分析代表多年数据集的大量3D图像数据的策略。个体之间骨适应的自然变异性很大，需要高通量方法来最大化连续观察的数量。第三个目标是建立方法，以整合硬组织和软组织的测量在高分辨率，使全面的FE模型可以开发代表关节的综合生物力学模型，研究组织的相互作用。* 总的来说，这项研究计划使用先进的成像和高性能FE建模来建立组织适应的机制模型，并将其应用于我实验室最近几项研究中获得的大型，丰富的数据集。这种方法为理解骨适应机制提供了重要的生物医学工程贡献。

Bone is a remarkably adaptive tissue that can rapidly remodel as a result of disease or injury. The three-dimensional (3D) microstructure of bone is key to understanding bone mechanics, and advancements of computed tomography (CT), coupled with customized finite element (FE) analysis methods, permit the analysis of how bone remodeling signals are distributed through the complex structure. Since 2002, my lab has made significant strides towards efficient and accurate computational modeling. This leads to enormous opportunities to advance our understandings of the mechanisms of bone adaptation through integration of technologies and the development of new computational approaches. Continuing with the long-term objective of my research program, this next phase will utilize novel longitudinal datasets to establish the fundamental mechanisms of bone adaptation under a variety of scenarios. It will couple analysis of time-series image data with FE modeling to directly link biological adaptations of bone to its mechanical and physiological functions. New directions also include developing multi-modal imaging approaches that integrate magnetic resonance imaging (MRI) and CT so that the functional interaction of key biological tissues, specifically cartilage and bone, can be explored. ******There are three main objectives of the next phase of my research program. First, establish a mechanistic model of bone adaptation that takes experimental longitudinal data of subjects who have (i) been exposed to microgravity for periods of six months (International Space Station astronauts), (ii) represent normal aging through our population-based study, and (iii) are undergoing experimental therapies to augment their bone strength. Coupling patient-specific FE models with measured local changes to bone microarchitecture provides a unique basis to learn about the mechanisms of bone adaptation. Second, advance high-throughput image processing, with the strategy to allow analysis of large volumes of 3D image data representing multi-year datasets. The natural variability of bone adaptation among individuals is large, and necessitates high-throughput approaches to maximum the number of serial observations. The third objective establishes methods to integrate hard and soft tissue measurements at high resolution so that comprehensive FE models can be developed that represent integrated biomechanical models of joints to study the tissue interactions. ******Overall, this research program uses advanced imaging and high-performance FE modeling to establish mechanistic models of tissue adaptation, and applies it to large, rich datasets that have been acquired through several recent studies in my lab. This approach provides an important biomedical engineering contribution toward understanding mechanisms of bone adaptation.