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A Sectioning, Coring, and Image Processing Guide for High-Throughput Cortical Bone Sample Procurement and Analysis for Synchrotron Micro-CT
Published on: June 12, 2020
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Drying irreversibly affects the elastic behavior of pelvic cortical bone
Marc Gebhardt1, Volker Slowik2, Hanno Steinke3
1Institute of Experimental Mechanics, Faculty of Civil Engineering, Leipzig University of Applied Sciences, Karl-Liebknecht-Str. 132, 04277, Leipzig, Germany; Institute of Anatomy, Faculty of Medicine, Leipzig University, Liebigstr. 13, 04103, Leipzig, Germany.
Journal of the Mechanical Behavior of Biomedical Materials
|February 14, 2024
Summary
Cortical bone stiffness increases when dried but rewetting causes irreversible stiffness loss, falling below initial levels. Storing specimens at 100% humidity best preserves their original biomechanical properties.
Area of Science:
- Biomaterials Science
- Orthopedic Biomechanics
- Materials Science
Background:
- Water content significantly influences the elastic properties of human cortical bone.
- Previous research shows conflicting results regarding the reversibility of bone's elastic behavior after rewetting.
Purpose of the Study:
- To investigate the reversibility of elastic behavior changes in human cortical bone due to moisture manipulation.
- To determine optimal storage conditions for preserving the in vivo-like mechanical properties of bone specimens.
Main Methods:
- Human cortical bone specimens (n=24) from the ischiopubic ramus were subjected to 11 moisture content variations.
- Elastic moduli were measured using three-point bending tests after moisture adjustment via desiccators and forced convection.
- Microscopic evaluation of reference samples was performed to rule out decay as a factor in stiffness changes.
Main Results:
- A reduction in water content correlated with increased bone stiffness, with complete drying raising the elastic modulus by approximately 83%.
- Rewetting significantly reduced stiffness, but to a level 24% below the initial state, indicating irreversible changes.
- Microscopic analysis showed no evidence of specimen decay, suggesting mechanical alterations rather than degradation.
Conclusions:
- The elastic behavior of cortical bone exhibits irreversible changes upon rewetting after dehydration.
- Storage at 100% relative humidity is recommended for biomechanical specimens to maintain in vivo-like material parameters.
- Understanding these moisture-dependent irreversible changes is crucial for accurate biomechanical testing and interpretation.
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