Computational framework for microstructural bone dynamics model and its evaluation

Bones are firm and solid organs that form the skeleton of the body. Bone consists of living tissues with which bone remodeling occurs asynchronously at various sites and involves resorption by osteoclast, followed by formation of new bone by osteoblast. Although bone is a simple composite of a mineral structure, its structure highly contributes to the strength of the bone. In this paper, we develop a computational framework for microstructural bone dynamics modeling which is capable of quantitative assessment of bone mineral density and bone microarchitecture. Our paper focuses on bone microstructure and remodeling dynamics based on a bone network model. First, we generate a bone network based on our bone model reflecting bone microstructure. Next, we introduce a mathematical model of autocrine and paracrine interactions among osteoblast and osteoclast. It allows us to calculate cell population dynamics and changes in bone mass at multiple sites of bone remodeling. Last, we analyze two bone networks representing healthy bone and bone with osteoporosis with our evaluation measurements. Our study provides an initial framework of bone remodeling simulation that can explain experimental observations in bone biology to explore bone diseases such as osteoporosis.