Elastic and viscoelastic properties of trabecular bone by a compression testing approach

Area of Science:

• Biomechanical Engineering
• Materials Science
• Orthopedic Research

Background:

• Trabecular bone exhibits viscoelastic properties, influencing its mechanical behavior under load.
• Accurate assessment of trabecular bone mechanical properties is vital for understanding bone health and disease.
• Existing compression testing methods present challenges in precision and accuracy.

Purpose of the Study:

• To review and analyze the advantages and disadvantages of various compression testing techniques for trabecular bone.
• To identify factors influencing the precision and accuracy of mechanical property measurements.
• To propose standardized testing conditions and specimen geometries for reliable results.

Main Methods:

• Review of literature on compression testing of trabecular bone, including destructive and non-destructive methods.
• Analysis of systematic errors associated with standard testing, such as specimen surface integrity and friction.
• Evaluation of specimen geometry effects on measured mechanical properties.

Main Results:

• Trabecular bone is confirmed as a viscoelastic solid.
• Non-destructive cyclic tests can determine viscoelastic properties (energy dissipation, loss tangent).
• Systematic errors (surface integrity, friction) can lead to a 20-40% underestimation of stiffness in standard tests.
• Specimen geometry significantly impacts mechanical properties; 6.5 mm cubes or 6.5x7.5 mm cylinders are recommended.

Conclusions:

• Standardized compression testing protocols and specimen geometries are essential for accurate and reproducible trabecular bone mechanical property assessment.
• Understanding and mitigating systematic errors are critical for reliable biomechanical data.
• Non-destructive testing offers valuable insights into viscoelastic behavior.