MicroCT-based finite element models as a tool for virtual testing of cortical bone

Area of Science:

• Biomechanics
• Materials Science
• Medical Imaging

Background:

• Assessing cortical bone biomechanics traditionally requires invasive physical testing.
• Microcomputed tomography (microCT) offers high-resolution imaging of bone structure.
• Developing non-invasive methods for bone property assessment is crucial for research and clinical applications.

Purpose of the Study:

• To evaluate a virtual biomechanics testing method using microCT data.
• To determine the accuracy of non-invasive methods for assessing cortical bone stiffness and strength.
• To establish the efficacy of microCT-based finite element modeling (µFEM) for bone property prediction.

Main Methods:

• Mouse femurs were scanned using microCT.
• Subject-specific finite element models were created incorporating spatial variations in bone properties.
• Empirical relationships between bone density and mechanical properties (Young's modulus, yield stress) were applied.
• µFEM results were compared against data from physical three-point-bend tests.

Main Results:

• MicroCT-based finite element analysis showed good correspondence with experimental tests for elastic stiffness and strength.
• Differences between experimental results and µFEM output were minimal: 6.1% for global stiffness, 1.4% for Young's modulus, 1.5% for yield stress, and 1.6% for yield force.
• The study validated the accuracy of the virtual testing approach.

Conclusions:

• Virtual biomechanics testing using microCT data can accurately predict the elastic-plastic properties of cortical bone.
• This non-invasive µFEM approach has the potential to reduce the cost, time, and number of specimens needed for physical experiments.
• The findings support the use of µFEM as a valuable tool in bone biomechanics research.