Finite Element Analysis of Biomechanical Outcomes Using Four Vertebral Modeling Methods in Adolescent Idiopathic Scoliosis

Adolescent Idiopathic Scoliosis (AIS) is a typical three-dimensional spinal deformity, and understanding its biomechanical mechanisms is essential for optimizing conservative treatment strategies. However, few studies have systematically compared different finite element (FE) modeling approaches. In this study, four patient-specific FE models were developed based on CT data from healthy individuals to investigate the effects of cortical bone modeling techniques (shell vs. solid elements) and intervertebral disc mesh types (tetrahedral vs. hexahedral elements) on model quality, computational efficiency, and biomechanical responses. All four models demonstrated reliable displacement predictions, although Model 4 showed distinct differences in peak displacement values. Hexahedral meshing of the intervertebral discs significantly reduced the number of elements and improved computational speed without compromising mesh quality. Additionally, using shell elements for cortical bone simplified the modeling process while maintaining a reasonable number of degrees of freedom. These findings provide quantitative guidance for selecting and optimizing FE modeling strategies in AIS-related biomechanical studies.