Modeling and remodeling in bone tissue

Abstract

Trabecular bone is a tissue with a complex 3-dimensional structure, consisting of struts and plates, which attains its mature morphology during growth in a process called ‘modeling’. In maturity, the tissue is renewed continuously by local bone resorption and subsequent formation in a process called ‘remodeling’. Both these metabolic activities are executed by bone-resorbing osteoclastic and bone-forming osteoblastic cells. It is known that bone mass and trabecular orientation are adapted to the external forces and that alternative loading conditions lead to adaptations of the internal tissue architecture. The question is how the characteristics of external loads are sensed in the bone, and how they are translated to structural adaptation of the tissue. The time scale of the underlying processes is on the order of months or even years. This aspect makes bone a complex research topic. In this paper we discuss the application of computer simulation to investigate the remarkable adaptive processes. We describe our developments of empirical models in the past 15 years, able to predict bone adaptation to external loads from a macroscopic level towards a cell-based level, in which the most important relationships of the cellular processes are captured. The latest model explains the morphological phenomena observed in trabecular bone at a microscopic level. Accepted for publication in: Theoretical Issues in Ergonomics Sciences