Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control, School of Mechanical Engineering, Tianjin University of Technology, Tianjin, China.
National Demonstration Center for Experimental Mechanical and Electrical Engineering Education, Tianjin University of Technology, Tianjin, China.
Comput Methods Biomech Biomed Engin. 2024 Nov;27(14):2071-2080. doi: 10.1080/10255842.2023.2270104. Epub 2023 Oct 16.
Different gravity fields have important effects on the structural morphology of bone. The fluid flow caused by loadings in the bone lacunar-canalicular system (LCS), converts mechanical signals into biological signals and regulates bone reconstruction by affecting effector cells, which ensures the efficient transport of signaling molecules, nutrients, and waste products. In this study, the fluid flow and mass transfer effects of bone lacunar-canalicular system at multi-scale were firstly investigated, and a three-dimensional axisymmetric fluid-solid coupled finite element model of the LCS within three continuous osteocytes was established. The changes in fluid pressure field, flow velocity field, and fluid shear force variation on the surface of osteocytes within the LCS were studied comparatively under different gravitational fields (0 G, 1 G, 5 G), frequencies (1 Hz, 1.5 Hz, 2 Hz) and forms of cyclic compressive loading. The results showed that different frequencies represented different exercise intensities, suggesting that high-intensity exercise may accelerate the fluid flow rate within the LCS and enhance osteocytes activity. Hypergravity enhanced the transport of solute molecules, nutrients, and signaling molecules within the LCS. Conversely, the mass transfer in the LCS may be inhibited under microgravity, which may cause bone loss and eventually lead to the onset of osteoporosis. This investigation provides theoretical guidance for rehabilitative training against osteoporosis.
不同的重力场对骨的结构形态有重要影响。骨陷窝-管道系统（LCS）中的载荷引起的流体流动将机械信号转换为生物信号，并通过影响效应细胞来调节骨重建，从而确保信号分子、营养物质和废物的有效运输。在这项研究中，首先研究了骨陷窝-管道系统在多尺度下的流固耦合效应和质量传递效应，并建立了三个连续骨细胞内 LCS 的三维轴对称流固耦合有限元模型。比较了在不同重力场（0G、1G、5G）、频率（1Hz、1.5Hz、2Hz）和周期性压缩加载形式下，LCS 内骨细胞表面的流体压力场、流速场和流体剪切力变化。结果表明，不同的频率代表不同的运动强度，这表明高强度运动可能会加速 LCS 内的流体流速，增强骨细胞的活性。超重力增强了 LCS 内溶质分子、营养物质和信号分子的传输。相反，微重力下 LCS 内的质量传递可能会受到抑制，这可能导致骨质流失，最终导致骨质疏松症的发生。这项研究为对抗骨质疏松症的康复训练提供了理论指导。
