The need to investigate the mechanical stresses in the hip bone, as a means of looking into the biomechanical causes of aseptic loosening of the acetabular component (of the total hip prosthesis), is established. The finite element technique is employed to evaluate stresses in the bone.

Since there was a lack of published literature on forces acting on the pelvis during one-legged stance a force model is developed.

A three dimensional finite element model of the normal hip bone is derived using geometrical data from a specimen hip bone. Using this model, mechanical properties from published literature and results of the force model the stresses in the hip bone are determined. It is not possible to compare results with any other reference due to lack of published work.

Three more finite element models are used to investigate stresses in the bone fitted with the Charnley, McKee-Farrar and Ring cups of the respective total hip prosthesis designs. A qualitative analysis of the effectiveness of the designs on a consistent basis is presented and the effect of other design parameters on their performance is also dealt with.

Similar stress analyses for the human femur and femur fitted with a Charnley prosthesis are included for a comprehensive treatment of the topic.