Optimization of Polyethylene Inserts Design Geometry of Total Knee Prosthesis

Abstract

Knee prostheses are produced from biomaterials which are compatible with human body as a result of damage of cartilage tissue due to various health problems. These prostheses consist of polyethylene parts between the Tibial Component and the femoral component of the femur. Polyethylene insert is used to reduce wear mechanisms between both materials. In this study, design library design parameters required for obtaining a polyethylene insert design were determined. These design parameters were modeled in the Solid Works Computer Aided Design (CAD) Program according to the L27 experiment design for each design parameter S / N ratios for three different levels using the Taguchi Method. For the safety coefficient analysis of each design, maximum forces in the literature were determined and implemented in Ansys Computer Aided Engineering (CAE) Program. According to the results of this analysis, maximum stress, weight and safety coefficient changes of each design geometry were determined. S / N ratios and% effects of each design parameter were determined by applying Taguchi and Variance Analysis. According to these results, the design is optimized by selecting the levels of each design parameter for the minimum weight and maximum safety factor. On the other hand, stress change graphs were obtained in different sections of the design. In the literature, for the first time, the design geometry of the polyethylene part was modeled by parametric design and optimum design was obtained.