a tubular bone 50 on which an artificial joint element 62 is fastened by way of an implant 7 according to the invention the stem 63 of the joint element 62 and liquefiable material 57 arranged around the stem represent the implant according to the invention which is pressed into the tubular bone 50 under the effect of ultrasound wherein the material 57 is liquefied and is pressed into pores of the cancellous bone 23 and into unevennesses of the inner surface of the cortical substance 22 of the tubular bone the stem 63 has a surface structure which is suitable for a positive fit connection to the liquefiable material 57 in the same manner as shown for plate 36 in fig1 a particularly advantageous embodiment of the stem 63 consists for example of titanium and has a porous surface that is thus bioactive and it is surrounded by resorbable liquefiable material such an implant has a primary stability directly after implantation which permits at least partial loading the primary stability is later taken over by a secondary stability effected by the intergrowth of vital bone tissue into the porous surface of the titanium stem 63 this means that the artificial joint element may be loaded essentially immediately after implantation but without the use of cement this early loading favors regeneration of the vital tissue and prevents atrophy osteoporosis all the same in a further phase vital tissue intergrows with the titanium stem fig2 likewise very schematically shows a joint 70 in the region of which a ligament 71 connects the bones 72.