title: Does increased bone-cement interface strength have negative consequences for bulk cement integrity? A finite element study.
abstract: Implant loosening is one of the most important modes of failure of cemented total hip replacement. It may be related to the cement strength, cement-prosthesis interface, cement-bone interface, surgical technique, or stem design. The main purpose of this study is to investigate the effect of bone-cement interface mechanical properties on cement degradation. The computational methodology proposed herein combines a previously developed bone-cement interface damage model and an accumulative damage model for bulk cement. This has been applied to a finite element model of an Exeter cemented hip implant. A higher strength of the bone-cement interface due to a higher amount of interdigitated bone results in faster cement deterioration. Over time, damage both at the bone-cement interface and in the cement mantle worsens. Also, a larger debonded area was predicted proximally, as observed in clinical practice. We conclude that the computational model proposed herein allows a realistic simulation of the bone-cement interface debonding and cement degradation, being a useful tool in the design of this kind of medical devices.
authors.affiliation: Group of Structural Mechanics and Materials Modelling, Aragón Institute of Engineering Research (I3A), University of Zaragoza, Betancourt Building, c/ María de Luna, 50018 Zaragoza, Spain. angeles@unizar.es
authors.forename: M A
authors.initials: MA
authors.lastname: Pérez
authors.forename: J M
authors.initials: JM
authors.lastname: García-Aznar
authors.forename: M
authors.initials: M
authors.lastname: Doblaré
mesh_terms: D000268:Adhesiveness; D001843:Bone Cements / Q000737:chemistry*; D001842:Bone and Bones / Q000737:chemistry*; D003198:Computer Simulation; D020342:Finite Element Analysis; D008422:Materials Testing; D008954:Models, Biological; D008956:Models, Chemical; D013718:Tensile Strength
chemical_list: D001843:Bone Cements