  The outcome of vertebroplasty is hard to predict due to its dependence on
complex factors like bone cement and marrow rheologies. Cement leakage could
occur if the procedure is done incorrectly, potentially causing adverse
complications. A reliable simulation could predict the patient-specific outcome
preoperatively and avoid the risk of cement leakage. Therefore, the aim of this
work was to introduce a computationally feasible and experimentally validated
model for simulating vertebroplasty. The developed model is a multiphase
continuum-mechanical macro-scale model based on the Theory of Porous Media. The
related governing equations were discretized using a combined Finite Element -
Finite Volume approach by the so-called Box discretization. Three different
rheological upscaling methods were used to compare and determine the most
suitable approach for this application. For validation, a benchmark experiment
was set up and simulated using the model. The influence of bone marrow and
parameters like permeability, porosity, etc., was investigated to study the
effect of varying conditions on vertebroplasty. The presented model could
realistically simulate the injection of bone cement in porous materials when
used with the correct rheological upscaling models, of which the
semi-analytical averaging of the viscosity gave the best results. The marrow
viscosity is identified as the crucial reference to categorize bone cements as
high- or low- viscosity in the context of vertebroplasty. It is confirmed that
a cement with higher viscosity than the marrow ensures stable development of
the injection and a proper cement interdigitation inside the vertebra.
