Modelling and simulation of acrylic bone cement injection and curing within the framework of vertebroplasty

TL;DR

This paper presents an integrated computational framework combining microstructural modeling, CFD, and finite element simulations to analyze acrylic bone cement injection and curing in vertebroplasty, enhancing understanding of the procedure.

Contribution

The study introduces a novel multi-stage simulation framework that models the entire process of cement injection and curing within human bone microstructure.

Findings

Successfully simulated cement injection into cancellous bone

Captured the thermo-mechanical behavior of cement during curing

Demonstrated the framework's applicability to real bone samples

Abstract

The minimal invasive procedure of vertebroplasty is a surgical technique to treat compression fractures of vertebral bodies. During the treatment, liquid bone cement gets injected into the affected vertebral body and therein cures to a solid. In order to investigate the treatment and the impact of injected bone cement, an integrated modelling and simulation framework has been developed. The framework includes (i) the generation of microstructural computer models based on microCT images of human cancellous bone, (ii) computational fluid dynamics (CFD) simulations of bone cement injection into the trabecular structure and (iii) non-linear finite element (FE) simulations of the subsequent bone cement curing. A detailed description of the material behaviour of acrylic bone cements is provide d for both simulation stages. A non-linear process-depending fluid flow model is chosen to represent the bone cement behaviour during injection. The bone cements phase change from a highly viscous fluid to a solid is described by a non-linear viscoelastic material model with curing dependent properties. To take into account the distinctive temperature dependence of acrylic bone cements, both material models are formulated in a thermo-mechanically coupled manner. Moreover, the corresponding microstructural CFD- and FE-simulations are performed using thermo-mechanically coupled solvers. An application of the presented modelling and simulation framework to a sample of human cancellous bone demonstrates the capabilities of the presented approach.