Computationally efficient modeling of cervical spinal cord injury without vertebral fracture

Finite element (FE) models are used to study spinal cord biomechanics and injury mechanisms. However, most existing models incorporate full vertebral geometry, substantially increasing computational cost and limiting the ability to perform large-scale parametric studies or apply modeling in clinically feasible timelines. In central cord syndrome, movement of the vertebrae is important while vertebral deformation contributes minimally to cord biomechanics. This study tested whether modeling the spinal canal geometry alone (versus full vertebral geometry) is sufficient to capture spinal cord stresses and strains under extension loading, offering a computationally efficient alternative to high-fidelity subject-specific models. Two FE models were developed: (1) a high-fidelity model including vertebrae, discs, ligaments, and neurological tissues, and (2) a computationally efficient (CE) model retaining only the spinal canal, with boundary conditions applied to represent the kinematics of each vertebra. Tissue-level stress and strain distributions, and computational performance were evaluated under extension. The CE model reproduced whole-cord and tissue-level stresses within 15% of the high-fidelity model, preserving stress/strain spatial distributions. Agreement between the two models was noted in their predicted tissue-level average and peak von Mises stress or minimum principal strain values. Computational time decreased approximately four-fold (2 vs. 8 days), while maintaining biomechanical fidelity. This demonstrates that vertebral bodies are not required to recover accurate spinal cord biomechanics in non-fracture cervical extension scenarios. These findings are based on this modeling framework, for the tested healthy geometry and extension scenario, with prescribed vertebral kinematics. This computational efficiency enables scalable parametric or population-level analyses of how individual differences in canal shape, cord morphology, or degeneration affect injury risk.