Effect of Crack Defects on Stress Intensity and Longevity of Hip Prostheses: A Finite Element Analysis

Abstract

This study aims to assess the impact of defects on the reliability and service life of hip prostheses. To understand crack behavior in hip prostheses, specifically in the acetabular part, the stress intensity factor (SIF) was evaluated, accounting for crack interactions within orthopedic cement and at the bone-cup interface. The analyses were carried out using programs based on the Finite Element Method (FEM). The study reveals that significant stress concentrations occur at the bone interface, particularly under different orientations of the femoral implant. In addition, the study analyzed the relationship between the physical changes in the crack on the prosthesis and the stress intensity factor across various modes. Results indicate that cracks initiated at the cement contour can propagate by opening and shearing the cracked lips.