Influence of Acetabular Liner Design on Periprosthetic Pressures during Daily Activities

摘要

In this study, periacetabular pressures produced by different acetabular liner geometries were analyzed using Finite Element Method. The cup models consist of hemispherical metal shells fitted with normal and different chamfered polyethylene liner geometries, with the same degree of femoral head coverage. The aim of this study was to understand the influence of the design parameters of the chamfered liners, which are primarily designed to increase the range of motion (ROM) of the hip joint and reduce the risk of impingement, on the acetabular contact pressures. The cup models were loaded to simulate periacetabular pressures during routine activities. The results show that the difference in contact pressure between the normal and chamfer models was not substantial in the given orientation of the cup. Also, the increase of the chamfer angle has a small influence on the maximum contact pressures, although that could be also dependent on the reduction of the polyethylene thickness. Pre-clinical testing of total hip prostheses using Finite Element Method enables the evaluation of contact pressures and stress distribution, and proves to be a valuable tool to analyze the parameters reducing the contact pressure.