[Metal spongiosa endoprostheses for surgical revision of the hip joint]

On the basis of 60 revision operations which were carried out on hip joints with mainly aseptic loosened cemented endoprosthesis and which also had, to some extent, distinct macrophagic induced osteolysis zones, it could be shown that implants with a metal spongiosa surface structure offer a good chance of an enduring revitalisation in the anchorage position and, thereby, are able to achieve a permanently stable endoprosthesis fixation. The expansion defects could be filled by means of homologous or autologous spongiosa transplantation. The post-operative X-ray check-up showed a vital inward-growing healing. All the endoprosthesis remained in situ during the follow-up examination period of, on average, 12.1 months. In accordance with the Merle D'Aubigne hip evaluation scheme, 43.3% showed an excellent result; 40% a good one; 13.3% were satisfactory; and only 3.4% showed a bad result. Major complications which occurred were: two intra-operative femoral stem fractures which had to be taken care of osteosynthetically; a repeat operation which had to take place during the first post-operative week because of a dislocation of the socket cup; and a luxation which was revised under narcosis. In spite of an increased periarticular ossification's ratio in revision operations, second-class ossification only occurred in 16.7% of all cases and third-class ossification did not occur at all.