Affiliations: [a] Faculty of Engineering, King Abdulaziz University, Jeddah, Saudi Arabia | [b] Faculty of Engineering, Mansoura University, Mansoura, Egypt
Correspondence:
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Address for correspondence: Prof. Dr. H.S. Hedia, Professor of Mechanical Engineering, Consultant of the University Vice President, Vice President Office, King Abdulaziz University, P.O. Box 80200, Jeddah 21589, Kingdom of Saudi Arabia. Tel.: +966 0545856959; E-mail: hassanhedia87@yahoo.com.
Abstract: Design of hip joint implant using functionally graded material (FGM) (advanced composite material) has been used before through few researches. It gives great results regarding the stress distribution along the implant and bone interfaces. However, coating of orthopaedic implants has been widely investigated through many researches. The effect of using advanced composite stem material, which mean by functionally graded stem material, in the total hip replacement coated with the most common coated materials has not been studied yet. Therefore, this study investigates the effect of utilizing these two concepts together; FGM and coating, in designing new stem material. It is concluded that the optimal FGM cemented stem is consisting from titanium at the upper stem layers graded to collagen at a lower stem layers. This optimal graded stem coated with hydroxyapatite found to reduce stress shielding by 57% compared to homogenous titanium stem coated with hydroxyapatite. However, the optimal functionally graded stem coated with collagen reduced the stress shielding by 51% compared to homogenous titanium stem coated with collagen.
