Hip joint prosthesis

Claim 1

A hip joint prosthesis for jointing the femur to the ilium which has an osseous corticalis surrounding a hollow space filled with sponge-like medulla and formed with a concave depression circumferentially surrounded by an osseous bead, comprising a socket member having a convex portion adapted to be received in the concave depression of the corticalis of the ilium, and a flange portion surrounding said convex portion and adapted to overlie and contact the corticalis of the bead when said convex portion is received in the concave depression of the ilium, said flange portion being formed with circumferentially distributed apertures to be aligned with bores which are provided in the corticalis of the bead and extend into the hollow space of the illium; and a plurality of expansion anchors for connecting said socket member to the ilium and including expansion anchor sleeves inserted into the respective apertures of said flange portion so as to extend into the bores in the corticalis of the bead and into the hollow space of the ilium, each of said expansion anchor sleeves including a leading portion of tubular configuration and provided with an internal screw thread, and a trailing portion extending from said leading portion and composed of a plurality of axially extending strips which are arcuately bent in transverse direction; and expander screws in said expansion anchor sleeves inserted through said trailing portion into meshing engagement with said screw thread and exerting an axial compressive force on said sleeve to effect radially outward buckling of said strips in the hollow space behind the corticalis until said expansion anchor sleeves are securely anchored behind the corticalis and said socket member is thus removably connected to the corticalis of the ilium.