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Updated: Aug 13, 2026
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Mouse Lumbar Vertebra Uniaxial Compression Testing with Embedding of the Loading Surface
Published on: December 1, 2023
Cortical and trabecular load sharing in the human vertebral body
Senthil K Eswaran1, Atul Gupta, Mark F Adams
1Orthopaedic Biomechanics Laboratory, Department of Mechanical Engineering, University of California, Berkeley, California 94720-1740, USA.
Summary
The vertebral cortical shell plays a substantial biomechanical role, sharing significant load with trabecular bone. Understanding this complex interaction is key to improving fracture risk assessment.
Area of Science:
- Biomechanics
- Orthopedics
- Gerontology
Background:
- The load-carrying capacity of vertebral bodies is critical for assessing fracture risk and treatment efficacy.
- The distinct biomechanical roles of the trabecular bone and cortical shell remain poorly understood.
Purpose of the Study:
- To investigate the biomechanical contribution of the vertebral cortical shell.
- To analyze the load sharing between cortical and trabecular bone in elderly vertebrae.
- To evaluate the impact of model assumptions on biomechanical assessments.
Main Methods:
- High-resolution microCT-based finite element models were created for 13 elderly human vertebrae.
- Parameter studies were conducted with and without endplates to isolate the shell's role.
- Load sharing mechanisms between cortical and trabecular bone were analyzed.
Main Results:
- The cortical shell, despite its thinness (0.38 mm average), accounted for a substantial portion of load-bearing (up to 54% at the narrowest section).
- Load sharing was complex and did not correlate with densitometric or morphologic properties.
- Endplate presence significantly altered the shell's load-carrying capacity.
Conclusions:
- The vertebral cortical shell has a significant biomechanical role, varying across different vertebral regions.
- Assessing bone strength solely through trabecular bone or midsection sampling is insufficient.
- An integrated approach considering both cortical and trabecular bone is necessary for improved noninvasive fracture risk assessment.
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