Computer Simulation of Bone Resorption Using a Hybrid Cellular Automaton Model

Bone remodeling is a dynamic process in which old bone is removed by osteoclasts and new bone is formed by osteoblasts. This removal and formation of bone are in balance maintaining normal bone mass. In catabolic bone diseases bone resorption is increased compared to bone formation, which leads to bone loss and eventually to bone fractures. The resorption behavior of osteoclasts has been extensively studied in-vitro. These experimental studies mainly focus on osteoclast development from precursor cells under the influence of growth factors and cytokines such as RANKL and MCSF. In addition to this, relationships between osteoclast size and resorption cavity have also been established. While these experiments deliver useful insights into the “stationary” behavior of individual osteoclasts, they are unable to address questions related to the dynamic process of bone resorption. In the present study, we use a computational modeling approach to study the dynamical behavior of bone resorption by osteoclasts. We have performed a computational simulation of bone resorption using both a finite element method (FEM) and a cellular automaton model (CAM). It is found that the process of bone resorption is affected by the strength of attractive interactions between osteoclasts, external mechanical loads, and blood vessel formation.