Research And Implementation Of Artificial Spine Prosthesis Modeling And Optimization Based On Finite Element Method

In recent years,spinal diseases have shown a tendency of being high and young.With the increase of the incidence of lumbar spinal injury,and the increase of serious diseases such as lumbar deformity,large-area fractures,and tumors,prosthetic replacement has become an effective method for the terminal treatment of these diseases.Although the patients can relieve the symptoms and retain the body's physiological movement after surgery,there is still a high incidence of postoperative complications such as settlement,displacement,and loosening in the long-term course of treatment.Therefore,it is of great practical significance to study the mechanical problems of the lumbar spine after prosthetic replacement,and find the structural defects of the prosthesis to optimize it.In view of this,this thesis establishes the lumbar mechanics model after prosthetic replacement and uses the finite element method to simulate the lumbar vertebrae physiology under human physiological activity.According to the experimental results,the bionic prosthesis optimization design scheme is proposed.The main research work is as follows:1.The normal lumbar L3-L4 segment solid model has been established by using existing computer visualization and 3D reconstruction techniques,based on CT and MRI data,combined with Mimics and Simpleware image processing software,including the upper and lower vertebral bodies,intervertebral discs,and partially connected ligaments.Through the study of traditional spine prostheses,combined with spinal prosthesis design theory to establish a prosthesis model.Then,the affected bone was removed on the basis of the normal model,and the prosthesis model was implanted at the model defect to establish a postoperative replacement lumbar model.2.On the basis of building a model,operations such as setting of material properties,meshing,and definition of surface connection relationships were performed.The loads and boundary conditions were loaded in the finite element analysis software ANSYS to simulate the stress of the two models under different physiological activities in the real human body,and the corresponding stress-strain cloud diagrams were obtained.3.Aiming at the defect of the prosthesis structure and referring to the normal human cancellous bone structure,the optimization scheme of the biomimetic micropore structure of the prosthesis was proposed.The finite element method was used to test the mechanical properties of the microporous titanium alloy,and the lumbar vertebral force condition after the optimized prosthesis replacement was theoretically simulated.The results show that the material can satisfy the mechanical strength of natural bone tissue.Through the analysis of the results,it was found that the stress of the prosthesis decreased and the distribution was more uniform,which increased the stability of the system.This provides a theoretical basis for guiding the further improvement of the spinal prosthesis.