Research On Personalized Design And Mechanical Properties Of Hip Prosthesis

In order to reduce stress-shielding effects and alleviate or eliminate postoperative complications,individualized hip prostheses matching the anatomical characteristics of the patient’s hip joint were designed and manufactured in this study.Starting from the appearance structure design of hip prostheses,the performance of hip prostheses manufactured using 3D printing technology was studied and analyzed.Based on reverse engineering technology,the human hip joint CT images were reverse modeled to establish a three-dimensional models of the femur,extract key features of the femur,determine the design size parameters of the hip prosthesis,and develop personalized design software for the hip prosthesis based on the Visual Basic platform and Solid Works API functions.A three-dimensional model of a individualized hip prosthesis matching the anatomical characteristics of the patient’s hip joint was established.Based on human anatomy theory,gait analysis was carried out,an experimental plan was formulated,and data on lower limb movements of five subjects were collected using the Qualisys three-dimensional motion capture system and the Kistler three-dimensional force platforms.The collected data were preprocessed using Qualisys Track Manager and Mokka and simulated using OpenSim human motion simulation software to obtain hip joint angle and joint force data,which were used as boundary conditions for finite element analysis.A finite element model of the femur after hip replacement surgery was established by simulating the hip joint replacement surgery,and finite element analysis was performed using gait loads as boundary conditions to obtain the stress shielding and sinking of the femoral surface of the prosthesis.The hip joint force was simplified,and the strain analysis of the femur before and after replacement was performed using the simplified force as the boundary condition to compare the performance differences between the individualized hip prosthesis and the standard hip prosthesis.Human femur and hip prosthesis solid models were prepared using 3D printing technology,and strain values at corresponding measuring points before and after hip replacement were obtained through electrical measurement experiment.By using the stress-strain calculation formula,the stress values on the femoral surface at the corresponding measuring points were calculated,and the stress shielding of the individualized hip prosthesis and the standard hip prosthesis were compared.The results of electrical measurement experiment were compared and analyzed with the results of finite element simulation to verify the accuracy of the finite element results.Through the above research work,a design method for personalized hip prostheses matching the anatomical characteristics of the patient’s hip joint was provided,and a hip prosthesis with excellent performance was finally obtained.The research project can provide new ideas and theoretical support for the design of individualized hip prostheses.