The loosening of femoral stem, which is caused by the lack of initial fixation, is one of the most important problems in THA. Cementless stems, becoming widespread recently, are constricted by the collapsed and densified cancellouse. However many of former studies on femoral stem fixation have not considered such mechanical properties and deformation of cancellouse bone. Thus we discussed how to reproduce the mechanical properties of cancellouse bone in stem stability analysis. We reproduced a stress-strain curve which consists of a linear elastic part and a plateau part by densification of collapsed cancellous bone applying a honeycomb material model of LS-DYNA. By this model, we could represent a stem insertion process and stem fixation by hoop steress of bone.
