Abstract: A method for fixing a joint prosthesis having an outer friction surface includes reaming a cavity in bone structure in which the prosthesis is to be applied and filling the cavity with grains of biologically compatible material. The stem of the prosthesis is driven down into the grain bed until it is substantially surrounded by the grains. The grains are subjected to an external force so that locking and compaction of the grains with respect to each other, and with respect to the prosthesis stem and bone tissue, is brought about. Preferably, the grains are irregular and/or plastic, having a particle size smaller than 5 mm, preferably between 0.5 and 2 mm. The prosthesis stem preferably is driven down into the grain bed by subjecting the grains, via the prosthesis, to vibrations of such a frequency that they are caused to fluidize.