Macroscopic Topology Optimization of Fusion Cages Used in TLIF Surgery
Titanium(Ti)cage is commonly used in transforaminal lumbar interbody fusion(TLIF)surgery.However,complications such as subsidence usually occur due to high mechanical stiffness of Ti.Meanwhile,the limited packing volume for bone grafts influences the fusion performance of fusion cage.Topology optimization was employed for the structure and stiffness adjustment of the fusion cage.A finite element model of L3–L4 lumbar spine was reconstructed based on CT images.Two commonly used cages(crescent and flat shaped)were optimized adopting the solid isotropic material with penalization model method.Optimized cages were built based on the result of topology optimization.The origin and optimized cages were implanted in the TLIF model and compared under four load conditions(flexion,extension,bending and torsion).The range of motion,stress on endplates and cages,the strain energy of cancellous were investigated for biomechanical evaluation of cages.The volume of optimized cages was reduced by 36%and 34%for the crescent and flat shaped cages,respectively.Macroscopic topology optimization of cages showed negligible influence to the ROM,von-Mises stress on the endplate and strain energy of cancellous.The stress on the optimized cages increased significantly.Macroscopic topology optimization increased the volume for bone grafts packing,which might improve the fusion performance.However,no significantly reduced risk of subsidence was observed with macroscopic topology optimization of cages.The effects of posterior pedicle screw system might not be considered in biomechanical evaluation of fusion cage,but should be considered in personalized customization of fusion cage.
Topology optimization Fusion cage Finite element analysis TLIF Lumbar spine
Hongwei Wang Yi Wan Xinyu Liu Bing Ren Zhanqiang Liu Xiao Zhang Mingzhi Yu
Key Laboratory of High Efficiency and Clean Manufacturing,School of Mechanical Engineering,Shandong Department of Orthopedics,Qilu Hospital,Shandong University,Jinan 250061,China
国际会议
浙江湖州
英文
647-660
2019-08-12（万方平台首次上网日期，不代表论文的发表时间）