Biomechanical Simulation of the Micro-dynamic Pedicle Screw

doi:10.12068/j.issn.1005-3026.2019.07.014

Abstract

Abstract: By using the finite element method， the biomechanical performance of the micro-dynamic pedicle screw was evaluated. A three-dimensional finite element model of lumbar segments L3-L4 was reconstructed based on CT images of human spine. And on this basis， three kinds of L3-L4 fixed models: rigid fixation(M1)， micro-dynamic fixation(M2) and hybrid fixation(M3) were built to calculate the biomechanical parameters of surgical segments under the simulative physiological load. The simulation results showed that the micro-dynamic pedicle screw increases the range of motion(ROM) of the fixation segments in the direction of flexion and extension(95% in flexion and 83% in extension). The dynamic performance of the screw improves load transmitting between the lumbar motor units， and increases the normal physiological stimulation stress of the endplates by 4.25%~5.7%. Besides， the micro-dynamic fixation reduces the stress concentration effect on the implants， and the reduction of the pedicle screw stress is 9.2%~16.2% under flexion， extension and lateral bending conditions.

Key words: lumbar, micro-dynamic pedicle screw, finite element, internal fixation, stress

CLC Number:

TG156

LIU Chuang， LIU Qi， YAN Yun-hui. Biomechanical Simulation of the Micro-dynamic Pedicle Screw[J]. Journal of Northeastern University Natural Science, 2019, 40(7): 986-990.

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