الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Total natural stress distribution in the pelvis and femur is significantly altered after total hip arthroplasty. When an implant is introduced, it will carry a portion of load, causing a reduction of stress in some regions of the remaining bone. This phenomenon is commonly known as stress shielding. The artificial hip joint consists mainly of two main parts: The acetabular component which inserted in the pelvis and the femoral component which inserted into the femur. There are problems associated with each component which tried to be solved in this thesis. It is found that a stiff metal backing (MB) which has widely used in acetabular cup design was initially believed to be mechanically favorable. Recent studies of the load transfer around the acetabular cups have shown that a stiff backing generates higher stress peaks around the acetabular rim, while reduces the stresses transferred at the central part of acetabulum (dome) causing stress shielding at this region of acetabulum. On the other hand, a stiff stem which inserted into the femur shields the proximal bone of the femur from mechanical loading. However, decreasing the stem stiffness increases the proximal femur interface shear stress and the risk of the proximal interface failure. Therefore, the purpose of this study is to tackle the stress shielding and stress concentration problems of the acetabulum, at the same time overcome the conflicting problems of the femur. The idea of this study is to control gradients and mechanical properties which is applied on the artificial hip joint using the concept of functionally graded materials (FGMs) in order to improve the performance of cementless total hip replacement (THR) through the concept of one and twodimensional FGMs.