Biomechanical Evaluation of a Spinal Screw （生物力学评价脊髓螺丝）.pdfVIP

Int. J. Morphol., 33(1):318-326, 2015. Biomechanical Evaluation of a Spinal Screw Fixation System by the Finite Element Method Evaluación Biomecánica de un Sistema de Fijación Espinal con Tornillo por el Método de Elementos Finitos * ** *** **** Ana Paula Macedo ; João Paulo Mardegan Issa ; Helton Luiz Aparecido Defino Antonio Carlos Shimano MACEDO, A. P.; ISSA, J. P. M.; DEFINO, H. L. A. SHIMANO, A. C. Biomechanical evaluation of a spinal screw fixation system by the finite element method. Int. J. Morphol., 33(1) :318-326, 2015. SUMMARY: The objective of the present study was to validate virtual models for the study of dual core and cylindrical screws and evaluate the influence of the geometry of the screws on the mechanical behavior and anchoring. Two models of dual core screws were used, one with a double thread and the other with a single thread, both with a conventional cylindrical screw were used in this study. The stiffness was assessed in a pullout test using polyurethane. Three dimensional virtual models simulating the pullout test were created for finite element analysis. To validate the models, the results were correlated with the mechanical tests. Tensions generated in polyurethane and the screw were studied while simulating the application of force in the direction of the screw pullout, of force transmitted by the rod with the individual standing at rest, and the force transmitted by the rod when performing flexion of the trunk. The dual core screws generated lower tensions in th