Planning of shelf operation in dysplastic hip by CT and MRI based finite element contact analysis

Abstract

Finite element contact analyses of dysplastic hip joints were performed based on CT and MR images as a surgical planning tool of the shelf operation. The 3-D cartilage thickness was approximated using MRI, and the joint contact force was calculated from a 3-D expansion of the Ninomiya's method. After surgical planning, the anatomical parameters including the CE angle, the AC angle, the sharp angle and the spheric sector angle were improved to normal hips. The mechanical parameters including the maximum contact pressure, the contact area and the quality of contact pressure distribution also were improved. The present models and the results can be used-as a computer simulation tool for optimal pre-operative planning of the shelf operation in hip dysplasia. Copyright © 2006 by The Japan Society of Mechanical Engineers.