[Bone and joint replacements with bioceramic endoprostheses].

Construction principles, mechanical and animal experiments with various types of endoprostheses consisting of dense alumina are reported as well as the first results in man. A stable implantation of this biocompatible material is possible, if the primary attachment by means of special construction features and subtile operation technique is ensured. The definite dixation of the implant is provided by the ingrowth of newly formed bone tissue in circular running indentations. Therefore the use of bone cement, one of the critical points in replacement surgery, can be avoided. In tumor surgery the replacement of the proximal humerus by a ceramic prosthesis has proven to be successful. Equally satisfactory results could be achieved in the therapy of osteoarthritis of the hip with a metal-ceramic composite endoprosthesis.