Finite Element Analysis of Cemented Hip Arthroplasty: Influence of Stem Tapers

Abstract

Abstract—Design of hip prosthesis is believed to be an important factor to minimize the aseptic loosening problems and to encourage long term stability. The numerous changes in the cemented femoral stem design have been intended to improve the long term performance of the implants, although have had other negative consequences. In this study, a finite element model of the implanted proximal femur to examine stresses behaviors in cemented hip arthroplasty with different tapered design of prosthesis. The calculated stress distribution is discussed with respect to stress shielding and bone remodeling issues in THR femur case. The taper of the prosthesis were design to be 3 ° at anterior/posterior, 3 ° at medial/lateral and 10° from wide lateral to narrow medial. Two different load cases representing walking (toe-off phase) and stair-climbing activities are investigated. Proper stress and strain distribution along the femur will enhance bone growth and keep the femur to function as normal as intact femur. Index Terms — aseptic loosening, hip arthroplasty, stem tapers, stress shielding. I.