Biomechanical Analysis of Knee Implant with and Without Bone Attachment Using Finite Element Method

Abstract

Degenerative arthritis is a disease that affects the line cartilage of the knee joint.It produces various injuries in the knee joint and may need a total knee replacement surgery of the affected knee with artificial components. Geometric complexity and non-linearity of the biomaterials of the knee make the logical solutions of the mechanical conduct of the knee joint difficult. In this study,3D modeling software,SolidWorks is used for modeling of knee implant and finite element method software ANSYS 15.0 is used for numerical estimation of equivalent stress, equivalent strain and total deformation.This study explains a human knee implant model using ANSYS 15.0 which shows multiple contact pairs working together.The objective is to find out the FEM results considering various loading state of knee implant with and without bone for various biomaterials,different meshing state of knee implant without bone for various steps. Also,this study compares these results and suggests the best biomaterial,mesh quality and time step for knee implant analysis for total knee replacement cases.A knee implant without bone static structure was able to sustain a load of 1500 N for material properties of ZrO2 demonstrating a stable stress value of 736.52 MPa.However,a knee implant without bone transient structure could sustain a time step of 0.001 sec at a medium mesh demonstrating a stable stress value of 455 MPa. It is seen that a knee implant with bone static structure was able to maintain a load of 700 N for material properties of Ti6Al6V showing a stable stress value of 1036 MPa.This implant model is a geometric contact path-dependent model that includes friction between bodies, which helps in understanding it's structural,and transient mechanical behavior,thus suggesting its practical use in the field of implant replacement/ prosthesis.