骨リモデリングによる損傷修復と力学的適応のシミュレーション

抄録

Bone maintains its strength by remodeling, which enables to repair microdamage and adapt its morphology to the surrounding mechanical environment. To effectively prevent a decrease in bone strength due to aging and diseases, it is necessary to understand how bone strength is maintained and decreased. However, the observation of changes in damage distribution and bone morphology within a living body is challenging. The objective of this study is to observe their changes through remodeling by simulating microdamage repair and mechanical adaptation. To achieve this, we constructed a mathematical model in which remodeling is regulated in response to damage and stress, and simulated remodeling in a cancellous bone. As a result, we observed the loss of some trabeculae, while other trabeculae maintained their load bearing function by mechanical adaptation concurrent with damage repair. The bone loss occurred because the rate of damage accumulation exceeded the rate of repair, leading to the spread of damage deep within the trabeculae. These results suggest that the loss of trabeculae through damage accumulation contributes to a decrease in bone strength. Our simulation platform, which enables to observe the process of microdamage repair and mechanical adaptation, will be a basis for understanding the effects of mechanical states on changes in bone strength by remodeling.