Anchoring element for implantation in tissue, for holding prostheses, artificial joint components or the like

An anchoring element formed of a tissue compatible material for extended prosthetic implantation in tissue comprising:

• a body of a generally rotationally symmetrical form having a central axis, the anchoring element having an outer peripheral surface provided with a screw thread having a thread crest, the thread crest being rounded in profile, and wherein a notch is formed across at least one turn of the screw thread for tissue growth into the notch when the anchoring element is implanted in the tissue, said notch dividing the thread into thread sections having lengths, the notch forming a key to inhibit rotation of the anchoring element in the tissue, the notch extending parallel with the axis of the anchoring element, and the width of the notch in the direction of the thread being substantially smaller than the length of each thread section.