Design and development of a new acetabular cup prosthesis

Historically, the main objective of Total Hip Replacements (THR) was to relieve pain and increase quality of life in the elderly and not normally intended for young active patients. With the current trend of performing THR on younger patients, the requirement is not only the increased longevity of the prosthesis but also increased performance for more strenuous activities. The acetabular cup design has far more impact on long-term survival of the THR than the femoral component. Optimising the acetabular cup produces a complex problem where the individual design factors have massive impact on the system. Changes in stress values, even caused by initial primary fixation during the operation, can result in stresses being transferred unfavourably. For optimisation of the acetabular cup, the properties of the natural hip must be retained by minimising both remodelling and bone resorption. This work has produced a novel acetabular cup prostheses with a ceramic on ceramic bearing surface that should last longer and perform better, thus reducing the necessity for costly and debilitating revisions. In addition, the use of the proposed novel anatomically orientated mechanical testing methods gives fast results and can also allow further insight into fatigue of alumina bearing couples in THR.