Objective: To develop a methodology to improve the representation of the mechanical properties of a vertebral finite element model (FEM) based on a new dual-energy (DE) imaging technology to improve pedicle screw fixation.
Methods: Bone-calibrated radiographs were generated with dual-energy imaging technology in order to estimate the mechanical properties of the trabecular bone. Properties were included in regions of interest in four vertebral FEMs representing heterogeneity and homogeneity, as a realistic and reference model, respectively. Biomechanical parameters were measured during screw pull-out testing to evaluate pedicle screw fixation.
Results: Simulations with property distributions deduced from dual-energy imaging characterization (heterogeneous models) induced an increase in biomechanical indicators versus with a homogeneous representation, implying different behaviors for the subject-specific models.
Conclusion: The presented methodology allows a patient-specific representation of bone quality in a FEM using new DE imaging technology. Consideration of individualized bone distribution in a spinal FEM improves the perspective of orthopedic surgical planning over otherwise underestimated results using a homogeneous representation.
Keywords: Dual-Energy Radiography; Finite Element Modeling; Pedicle Screw; Subject-Specific Modeling.