A novel concept for the manufacture of individual sapphire-metallic hip joint endoprostheses

Abstract

During the last decade, hip joint endoprostheses have been ever more widely carried out in orthopaedic practice in the world; more than 400 000 operations are performed every year and more than 100 types of endoprosthetic construction have been designed [1, 2]. The best known are those of Biomet, Zimmer (USA), and Aesculap (Germany), in which metallic and polymer or ceramic and polymer joints are used. Analysis of the results of endoprosthetic operations on joints show that in 7–12% of cases 2–3 years later, and in 25–30% of cases 5–7 years later, complications arise that are generally deleterious to the health of the recipient [3]. The most frequent and dangerous complication is an aseptic shattered condition of the endoprosthesis in the bone tissue, which leads to the necessity of recurrent operations. One of the negative factors leading to this condition is friction in the hinge of the artificial joint, releasing nanoparticles produced from the endoprosthetic material. Furthermore, different loads in the hinge of the endoprosthesis during walking cause friction in the components of the joint and it wears out (see Fig. 1). A novel concept for the manufacture of individual sapphire-metallic hip joint endoprostheses A.G. Mamalis, J.J. Ramsden, A.I. Grabchenko, L.A. Lytvynov, V.A. Filipenko and S.N. Lavrynenko 1 Laboratory of Manufacturing Technology, National Technical University of Athens, Greece 2 Advanced Materials Department, Cranfield University, UK 3 Department of Integrated Technologies in Mechanical Engineering, National Technical University Kh. P. I., Kharkov, Ukraine 4 Institute for Single Crystals, National Academy of Science of Ukraine, Kharkov, Ukraine 5 Sytenko Institute of Spine and Joint Pathology, Ukrainian Academy of Medical Sciences, Kharkov, Ukraine