The Establishment And Appliment Of The Three-Dimensional Finite Element Model Of Cerical Spine

Objective:â‘ The introduction of contact theory and the establishment of three-dimensional finite element model of the whole cervical spine were initial applicated in cervical spine biomechanical analysis.â‘¡The model was used to explore the range of motion of adjacent segments and disc stress change after cervical interbody fusion and artificial disc implantation.Method:â‘ A three dimensional finite element model of cervical spine was established from the CT scan images of a cadaver cervical spine, Solid-Wor ks2003,HyperMesh and ANSYS11.0. Different material was assigned different mechanical parameter, and we created a cervical three-dimensional finite element model.After setting the boundary,under the 73.6N preload the model is loaded the 2.0Nm moment to simulate the flexion/extension, left/-right bending and rotating.The relationship of movement and displacement will compare with the results of experiment in vitro.â‘¡C5/6 intervertebral fusion model,C5/6 of artificial disc implantation model,and then pre-load 73.6N imposed,2.ONm a pure torque,analyze its adjacent segments in the spine flexion,extension,left and right flexor,left rotation adjacent segment of the scope of activities and the force of intervertebral disc.Result:â‘ The model has 372896 solid elements and 97705 points.Far more than the previous model established by the unit number of nodes,and the establishment of a ligamentjoint capsule and other soft tissue structures, a-nd facet joints in a surface,contact unit,the integrity of the structure,accura-te measurement of the spatial structure high.â‘¡Interbody fusion surgery near the intervertebral range of motion increased,the corresponding stress significantly increased intervertebral disc,nucleus pulposus and annulus fibrosus upper segment increased markedly by about 70%,the next-bit segments of nucleus pulposus and annulus stress by about 40%;after implantation of artificial disc cervical spine range of motion after the extension is limited addition (p>0.05),other activity was no difference between adjacent disc segment increased stress of not more than 10%.Conclusion:â‘ In this study, the modeling method is convenient and fast,The model was true and reliable,which could be used in orthopedic biomechanics analysis of the preliminary work,and to provide theory and data for clinical works.â‘¡Compared with interbody fusion,the artificial disc implantation could relief the stress of adjacent segments within a certain range and resume the normal activity of cervical spine.