The contact stress calculations in artificial hip-joint by finite element method

Abstract

The artificial human hip joint is made up of a metallic femur head and ultra high molecular weight polyethylene (UHMWPE) cup. The stresses in the joint are affected by the shape or the design of implant, the size or the dimensions of the implant, the material of the implant and the clearance in the joint. In this study, a 3D model of the artificial hip joint is analysed by finite element method to investigate contact stresses developed in the cup. Three different materials, namely titanium (Ti) alloy, stainless steel (SS) and cobalt chromium steel (CoCrMo) are used for femur heads. The results for femur head diameters of 22 mm to 36 mm are presented. Ti-Al alloy femur heads show the lowest values for the contact stresses than SS and Co Cr Mo femur heads. The larger the diameter, the lesser are the stress values due to increase in contact area.