Abstract
Damage accumulation and failure in the cement polymethylmethacrylate (PMMA) is the most prominent scenario in a cemented total hip arthroplasty (THA) leading to eventual implant loosening. In this study, a three-dimensional finite element method (FEM) is used to analyse by computing the stress intensity factor (SIF) along the crack tip, the behaviour of a rectangular crack emanating from bone inclusion and an elliptical crack in the cement mantle of hip stem. To predict the location of crack initiation, stress distribution around the bone inclusion under body load is computed. From stress results, it has been found that the bone inclusion located in the proximal zone of the prosthesis is subjected to the higher stress field. Stress intensity factors for crack emanating from bone inclusion are higher than those for the elliptical crack; therefore, the risk of crack propagation by opening mode in the proximal zone is more significant than distal and medial ones.