Understanding bone strength and fracture by multiscale modeling, testing and imaging: the role of chemical composition and hierarchical structure

通过多尺度建模、测试和成像了解骨强度和骨折：化学成分和分层结构的作用

• 批准号: RGPIN-2019-05372
• 负责人: Luo, Yunhua
• 金额: $ 2.84万
• 依托单位: University of Manitoba
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=687460
• 关键词: Understanding; bone; strength; fracture; multiscale

My research program is to study bone strength and fracture by multiscale computational modeling, mechanical testing and imaging. Bone fracture is determined by bone strength and the applied force, and bone strength is in turn determined by bone chemical composition and architecture. Bone has complicated chemical compositions and hierarchical nano-micro-structures. With the existing theories and models established from previous studies that were mostly conducted at macroscale using whole bones or bone specimens, we still do not know how bone strength at macroscale are quantitatively affected by chemical compositions and nano-micro-structures, and how an impact force causes a fracture at a specific site of a bone. To better understand bone strength and fracture, one has to understand the hierarchical architecture of this fascinating material at the molecular, cellular, tissue, organ, and whole body levels, in conjunction with an understanding of the mechanical environment surrounding the body. It is still a long way for biomechanical and biomedical researchers to go. Multiscale modeling is a promising method to understand bone mechanical behavior, but it is still under development. The long-term objective of my research program is to contribute to the establishment of multiscale theories and models for bone strength and fracture. In my previous Discovery Grant (DG) term, I developed a hierarchy of three-level biomechanical models at macroscale to understand the biomechanics involved in fall-induced hip fracture. The short-term objective of my next DG term is to study bone strength and fracture at smaller length scales, i.e. to understand how bone chemical composition (mineral, organic matter and water) and nano-micro-structure (pores and crystal sizes) affect bone strength and fracture. The proposed research will contribute to: (1) the establishment of relationships between bone stiffness/strength and chemical compositions/structures across different scales; (2) the development of multiscale biomechanical models of bone strength and fracture. ***The proposed research would have a major impact on the communities of Biomechanical/Biomedical Engineering and Materials Engineering. For example, the multiscale models of bone strength and fracture would help biomechanical engineers improve the effectiveness of protective devices in manned vehicles. The relationships between bone stiffness/strength and chemical compositions/structures would help biomedical engineers improve evaluation of fracture risk and advance design of 3D printed bone crafts; it would also inspire material engineers to design novel and efficient composite materials. Highly qualified personnel trained in the proposed research would be equipped with cutting-edge knowledge and techniques of material multiscale modeling, which will be necessary for innovations in both Biomechanical/Biomedical and Materials Engineering.**

我的研究项目是通过多尺度计算模型、机械测试和成像来研究骨骼强度和骨折。骨折由骨强度和施加的力决定，而骨强度又由骨化学成分和结构决定。骨骼具有复杂的化学成分和分层的纳米微米结构。现有的研究建立的理论和模型大多是在宏观尺度上使用整骨或骨标本进行的，我们仍然不知道宏观尺度的骨强度如何受到化学成分和纳米微观结构的定量影响，以及影响如何力会导致骨骼特定部位骨折。为了更好地了解骨骼强度和骨折，人们必须了解这种令人着迷的材料在分子、细胞、组织、器官和全身水平上的层次结构，同时了解身体周围的机械环境。对于生物力学和生物医学研究人员来说，还有很长的路要走。多尺度建模是了解骨骼力学行为的一种有前景的方法，但仍在开发中。我的研究计划的长期目标是为建立骨强度和骨折的多尺度理论和模型做出贡献。在我之前的发现资助 (DG) 任期中，我开发了宏观层面的三级生物力学模型层次结构，以了解跌倒引起的髋部骨折所涉及的生物力学。我下一个 DG 学期的短期目标是研究较小长度尺度下的骨骼强度和断裂，即了解骨骼化学成分（矿物质、有机物和水）和纳米微观结构（孔隙和晶体尺寸）如何影响骨强度和骨折。拟议的研究将有助于：（1）建立不同尺度的骨硬度/强度与化学成分/结构之间的关系； (2)骨强度和骨折多尺度生物力学模型的发展。 ***拟议的研究将对生物力学/生物医学工程和材料工程界产生重大影响。例如，骨骼强度和骨折的多尺度模型将帮助生物力学工程师提高载人车辆中保护装置的有效性。骨骼刚度/强度与化学成分/结构之间的关系将有助于生物医学工程师改进骨折风险的评估并推进 3D 打印骨骼工艺品的设计；它还将激励材料工程师设计新颖高效的复合材料。在拟议研究中接受培训的高素质人员将配备材料多尺度建模的尖端知识和技术，这对于生物力学/生物医学和材料工程的创新是必要的。 **