Abstract
Numerical modeling has been extensively employed to understand the biomechanics of the spine. Often, patient-specific models developed from medical scans, which are specific to an individual and their particular clinical case, are used. The aim of this study was to develop a generic model of the full adolescent spine, which includes ribs, muscles, and ligaments, that can effectively simulate realistic spinal biomechanics. The model was developed using computer-aided design, incorporating anatomical parameters to represent a 15-year-old adolescent full-spine geometry. Essential components like the ribcage and related musculature were included to capture realistic biomechanics. The model appraisal involved mesh sensitivity analysis and tests on selected functional spinal units (FSUs) in each spinal region to assess the biomechanics of specific components of the full spine. Biomechanical responses, including range of motion, intradiscal pressure, and facet joint forces, were evaluated across multiple simulated loading tasks. Results were compared to previous in vitro and in silico studies. Our model demonstrated good agreement with previous experimental and numerical studies. The ribcage inclusion simulated the stiffening effect observed in vivo satisfactorily. Ligamentous effect tests on thoracic and lumbar FSUs indicated that the model satisfactorily replicated expected biomechanical responses. The study shows that the developed model can be employed effectively to simulate real-life spine motions. The developed model will be used for future AIS research, enabling the investigation of surgical treatment outcomes across diverse clinical scenarios.