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Subject-specific Musculoskeletal Model for Studying Bone Strain During Dynamic Motion
Published on: April 11, 2018
A Novel Decomposition-Based Growth Model for Simulating Stress-Modulated Spinal Growth
Serhat Onur Çakmak1,2, Ercan Gürses1
1Department of Aerospace Engineering, Middle East Technical University, Ankara, Turkey.
Summary
A new finite element method simulates spinal growth using the Hueter-Volkmann law, offering improved stability and efficiency for modeling adolescent idiopathic scoliosis (AIS). This approach enhances understanding of spinal deformities.
Area of Science:
- Biomechanics
- Computational Biology
- Orthopedics
Background:
- Spinal growth modeling is crucial for understanding progressive deformities like adolescent idiopathic scoliosis (AIS).
- Existing methods often lack numerical stability and computational efficiency, especially under large deformations.
- The Hueter-Volkmann law, relating compressive stress to growth inhibition, is a key principle in spinal growth.
Purpose of the Study:
- To develop and validate a novel, decomposition-based finite element methodology for simulating mechanobiological spinal growth.
- To compare the proposed method with the traditional sequential approach for accuracy, stability, and computational cost.
- To introduce an improved technique for calculating the wedge angle in spinal models.
Main Methods:
- A large deformation finite element framework incorporating the Hueter-Volkmann law via multiplicative decomposition of the deformation gradient.
- Implementation of a sequential method for comparative analysis.
- Simulation of a simplified Functional Spinal Unit (FSU) under various loading conditions over a two-year period.
- Development of a wedge angle calculation method using least plane fitting.
Main Results:
- The decomposition-based approach demonstrated superior numerical stability and lower computational complexity compared to the sequential method.
- Both methods yielded comparable wedge angle progression, but the new method produced smoother deformations and less element distortion.
- The improved wedge angle calculation enhanced geometric accuracy and reduced mesh sensitivity.
Conclusions:
- The novel decomposition-based finite element method provides a reliable and efficient framework for long-term spinal growth simulations.
- This approach offers a more realistic representation of the spinal growth process.
- The methodology lays a strong foundation for future patient-specific modeling and clinical applications in spinal deformities.
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