Dynamic analyses of osteoblast vibrational responses: A finite element viscoelastic model

Abstract

Mechanotransduction is an important process that influences bone remodeling and maintains viability of bone cells. To understand the effect of the vibrational mechanical stimulation on biomechanic responses of bone cells, a viscoelastic osteoblast finite element (FE) model was developed. Firstly, the mode shapes and natural frequencies of a spreading osteoblast were assessed using the FE modal analysis. The osteoblast FE model predicted the natural frequencies of osteoblasts (within the range about 19.99-34.48 Hz). Then, the effect of acceleration on the vibrational responses of in-vitro cultured osteoblasts was investigated. Three different accelerations of base excitation were selected (0.15 g, 0.3 g and 0.5 g, where g = 9.8 m/s2) and the vibrational responses (displacement, strain and stress) of osteoblasts were simulated. It was found that values of displacement, strain and stress increase with the increase of base excitation acceleration. In addition, the response values in Z-direction are much higher than those in the other directions (X, Y-direction) for the same base excitation acceleration. These findings will provide useful information to understand how vibrational mechanical stimulus influences bone cells and provide guidance for in vitro cell culture and experimental research and ultimately clinical treatment using the external vibrating loading.