Finite element model

This study aimed to develop a comprehensive, anatomically accurate three-dimensional finite element model of the entire spine and thoracic cage of an adult Chinese male, with the objective of enabling quantitative biomechanical analysis of manual therapies such as Tui Na. Methods: High-resolution CT imaging data were acquired from a healthy male volunteer, and a multi-software modeling workflow—comprising Mimics, Geomagic Wrap, SolidWorks, and ANSYS Workbench—was employed to reconstruct detailed anatomical structures, including vertebrae, intervertebral discs, costal cartilage, sternum, ribs, thoracic joints, ligaments, lungs, heart, and major respiratory muscles. Results: The resulting FE model consisted of 374,852 nodes and 470,524 shell elements, with material properties assigned based on literature values. To ensure model accuracy, both static and dynamic validations were conducted. The T12–L1 functional spinal unit was subjected to six loading conditions, and the moment–rotation curves showed strong concordance with experimental data from previous studies. Additionally, a frontal thoracic impact simulation was performed and compared against cadaveric impact test results, yielding a 5.3% error in peak impact force and a 1.25% error in chest compression. These results confirm the biomechanical reliability and physiological validity of the model. Conclusions:In conclusion, the developed FE model provides a robust computational platform for investigating mechanical responses under manual therapy interventions and offers a valuable tool for future biomechanical studies of Tui Na techniques.