Development and validation of lumbar spine finite element model

Area of Science:

• Biomechanics
• Computational modeling
• Spinal research

Background:

• Finite element method (FEM) simulations improve understanding of lumbar spine biomechanics.
• Existing models require enhanced soft tissue behavior descriptions.

Purpose of the Study:

• Develop and validate a modified lumbar spine finite element model for biomechanical research.
• Improve the accuracy of soft tissue modeling in the lumbar spine.

Main Methods:

• Modified the adult male Total Human Model for Safety (THUMS) v6.1 finite element model.
• Applied orthotropic and nonlinear material properties to ligaments, and hyperelastic properties to the annulus fibrosus and nucleus pulposus.
• Implemented collagen fiber content and nucleus pulposus separation, then subjected the model to various loading conditions.

Main Results:

• The modified model accurately predicted intervertebral ranges of motion across all loading modes.
• Intradiscal pressure results showed good agreement with existing literature data.
• Validated numerical results against experimental data in the sub-injurious range.

Conclusions:

• The enhanced finite element model provides a more accurate representation of the human lumbar spine.
• The modifications allow for better prediction of lumbar spine behavior under diverse mechanical loads.
• This improved model can advance biomechanical research and injury prevention strategies.