Mechanical characterization and modeling of the skull of children affected by craniosynostosis

Resumo

There are five bones that form a childrens's calvaria: two frontal, two parietal, and one occipital, connected by four sutures and two fontanelles. The sutures are bands of fibrous connective tissue that allow cranial expansion during brain development. Craniosynostosis is a condition affecting 1 in every 2,000 births, characterized by the premature fusion of cranial sutures, and it is the second most common craniofacial anomaly. This condition can lead to cranial and facial deformities, intracranial hypertension, and significant impairments in neurological development. Diagnosis is based on clinical examination and three-dimensional computed tomography, and treatment is predominantly surgical. This study proposes a methodology for the biomechanical modeling of the infant skull with sagittal craniosynostosis, focusing on the mechanical characterization of the cranial suture. To this end, two geometric models were developed: a simplified one to simulate three-point bending tests and another based on tomographic reconstruction of the complete skull. Through inverse analysis, the elastic modulus of the sagittal suture was estimated. In addition, simulations with different mechanical properties were performed using the finite element method to evaluate the effect of tissue stiffness on stress and deformation distribution. This methodology contributes to a better understanding of the biomechanical role of fused cranial sutures in bone development and lays the foundation for future studies with experimental validation and more advanced modeling.