Numerical Simulation And Experimental Study On Artificial Hip Replacement

The main methods to treat the hip disease that include external fixation,internal fixation and hip replacement at present.If the function of the hip joint was lost and drug treatment invalid,however,artificial hip replacement surgery is the most effective method to recover the function of hip joint.But the implantation of the prosthesis will change the original mechanical distribution and may cause complications such as bone resorption and bone atrophy.Therefore,it is very meaningful to study the stress and strain distribution of hip after replacement.The precise coordination of the angle between the prosthesis and the femur has a direct impact on the distribution of stress and strain on each part of the hip joint in the artificial hip replacement,it also critical for the success of the surgery and the life of prosthesis after hip replacement.In this paper,we established the hip joint model with different neck angles and anteversion angles to study the effect to the strain and stress distribution laws of the hip joint after the total hip replacement.Specific research content is as follows,(1)By the mean of numerical simulation,two models of hip joint without pelvis and pelvis after replacement were established.Based on ANSYS,the hip joint model was numerically simulated,and the strain distribution of the hip joint was obtained.The points of large strain value and special location were selected as the measuring point in the electrical test.(2)Using the method of electric test experiment,the elastic modulus of the models with different materials and structures were obstained after tension and pressure experiment,and one of the models was selected as the electrical test model after comparison the merits and faults of the models.(3)The accuracy of two models without pelvis and pelvis after replacement was verified by numerical simulation and electrical test.By comparing and analyzing the results of the stress and strain distribution of the two models,the model of the pelvis hip joint was selected as a model for the follow-up parameter study.(4)The parameters of hip replacement were studied.The neck angles and anteversion angles are different in the individuals,so the hip joint models with different angle parameters were established to have the numerical simulation and to obtain the laws of stress and strain distribution of each part of the models.The results of numerical simulation were analyzed and compared,and the influence of the neck angles and anteversion angles on the stress and strain distribution of hip joint were obtained.Considering the bone mineral density of different ages people are difference,the models were given different bone material parameters to study the effects of different bone after hip replacement for the femur and prosthesis.