title: [Bone fixation of tumor endoprostheses with cast-on spherules of a cobalt-base alloy].
abstract: Special tumor endoprostheses manufactured from cobalt-base alloy with cast-on globules upon the intramedullary shaft and two paracortical flanges for screw fixation can be stabilized at the ends of long bones without using bone cement. Three such implants, retrieved in clinically stable condition after 3 months (proximal tibia), 5 months (distal humerus), and 13 months (distal femur), were investigated microscopically: new bone was found immediately adjacent to the porous surface structures and the fixation screws in many areas. The contribution of bone fragments originating from the preparation of the implant bed to this bone reaction was extremely slight. On the other hand, fibrous tissue layers and a foreign body reaction were found on the remaining surfaces, which may have been related to the compatibility of the implant material and must therefore be regarded as detrimental for the long-term prognosis concerning the fixation of such implants.
mesh_terms: D001859:Bone Neoplasms / Q000556:secondary / Q000601:surgery*; D001863:Bone Screws; D001842:Bone and Bones / Q000473:pathology; D003035:Cobalt; D006801:Humans; D007595:Joint Prosthesis; D011183:Postoperative Complications / Q000473:pathology; D011474:Prosthesis Design
chemical_list: D003035:Cobalt
vernacular_title: Die Knochenverankerung von Tumorendoprothesen mit angegossenen Kügelchen aus Kobalt-Basislegierung.