Pelvic Construct Prediction of Trabecular and Cortical Bone Structural Architecture

Area of Science:

• Biomechanics
• Computational modeling
• Orthopedic research

Background:

• The pelvis is crucial for weight transfer and organ protection.
• Pelvic trauma has high mortality rates, necessitating better understanding and modeling.
• Existing models may not fully capture the complex structural behavior of the pelvic construct.

Purpose of the Study:

• To develop a mesoscale structural finite element (FE) model of the pelvic construct.
• To simulate daily living activities and bone adaptation within the pelvis.
• To validate the model's accuracy against existing data and assess its sensitivity.

Main Methods:

• Utilized shell elements for cortical bone and truss elements for trabecular bone, ligaments, and joints.
• Employed a strain-driven bone adaptation algorithm to simulate daily activities (walking, stair negotiation, sit-to-stand).
• Validated the adapted model against CT scans and compared strain predictions with a continuum CT-derived model.

Main Results:

• The adapted model showed good qualitative agreement with CT scans regarding cortical thickness and trabecular architecture.
• The model demonstrated high sensitivity to target strain changes, impacting bone volume predictions.
• Strain predictions from the structural model correlated well (r=0.813, 0.809) with a continuum CT-derived model.

Conclusions:

• The developed mesoscale FE model accurately represents pelvic structure and adaptation.
• The model is a valuable tool for applications including fracture modeling and the design of surrogates.
• Further research can leverage this model for advanced orthopedic applications and injury analysis.