Human vertebral body apparent and hard tissue stiffness

Area of Science:

• Biomechanics
• Orthopedic Research
• Materials Science

Background:

• Cancellous bone's mechanical properties depend on tissue material characteristics and trabecular bone structure.
• Accurate prediction of bone mechanical behavior is crucial for understanding skeletal health and disease.

Purpose of the Study:

• To utilize microstructurally accurate large-scale finite element (LS-FE) models to predict the apparent stiffness of human vertebral cancellous bone.
• To estimate the stiffness of the hard tissue within the trabecular bone structure.

Main Methods:

• Generated 28 LS-FE models from microcomputed tomography images of human vertebral cancellous bone specimens.
• Performed mechanical testing to determine experimental apparent stiffness and strength.
• Calculated morphometric parameters including bone volume fraction (BV/TV) and fabric tensor eigenvalues.

Main Results:

• LS-FE models explained significant variance in experimental apparent stiffness (r2=0.89) and strength (r2=0.87).
• LS-FE estimated apparent stiffness was the sole significant predictor of experimental apparent stiffness and strength.
• Hard tissue stiffness varied among individuals but showed no significant correlation with age, sex, race, or weight.

Conclusions:

• LS-FE modeling provides a reliable method for predicting the apparent mechanical properties of human vertebral cancellous bone.
• Trabecular architecture, as captured by LS-FE models, is a primary determinant of bone mechanical performance.
• Individual variability in hard tissue stiffness exists but is not explained by common demographic or morphometric factors in this cohort.