Continuum finite element analysis generalizesin vivotrabecular bone microstructural strength measures between two CT...

Area of Science:

• Biomedical Engineering
• Radiology
• Orthopedics

Background:

• Osteoporosis increases trabecular bone (Tb) fragility, leading to bone loss and fracture risk.
• Accurate in vivo assessment of Tb strength is crucial for osteoporosis management and understanding pathogenesis.
• High-resolution CT technology offers potential for in vivo Tb imaging but faces challenges due to scanner resolution variations.

Purpose of the Study:

• To present and evaluate nonlinear continuum finite element (FE) methods for computing Tb strength from in vivo CT imaging.
• To assess the generalizability of these FE methods between CT scanners with different image resolutions.

Main Methods:

• Nonlinear continuum finite element (FE) methods were developed to compute Tb strength from in vivo CT images.
• Ankle images from twenty healthy volunteers were acquired using low- and high-resolution CT scanners on separate occasions.
• Reproducibility and stress propagation patterns were analyzed under various loading conditions.

Main Results:

• Continuum FE-based Tb strength measures demonstrated high reproducibility (ICC ≥ 0.93) between scanners.
• FE stress propagation was primarily confined to the Tb micro-network, with minimal leakage into the marrow space.
• Results complied with fundamental mechanical principles for in vivo imaging.

Conclusions:

• Nonlinear continuum FE-based Tb strength measures are reproducible across different CT scanners.
• These methods are suitable for multi-site longitudinal human studies, advancing osteoporosis research and clinical assessment.