Numerical simulation of cancellous bone remodeling using finite difference time-domain method

Abstract

Cancellous bone remodeling, which is a couple of bone formation and resorption on the trabecular surface, was numerically simulated using finite difference time-domain (FDTD) method with a voxel finite element (VFE) model of bovine cancellous bone. Assuming that the bone formation/resorption could be generated on the trabecular surface where the local stress under the mechanical load was larger/smaller than the surrounding stress, the voxel elements in the cancellous bone model were added/removed. An ultrasound wave at 100 kHz was applied to cancellous bone as the mechanical load, and the local stress was calculated using the FDTD method. In the case of the ultrasound transmission in the direction parallel to the main orientation of the trabecular network, both orientations in the trabecular and pore structures became stronger as the bone remodeling advanced. On the other hand, in the case of the transmission in the perpendicular direction, these orientations became weaker. In the remodeling simulation, the realistic change in the trabecular structure with the porosity could be observed.