Fastening means for hip joint prosthesis sockets

• US 3,939,497 A
• Filed: 12/09/1974
• Issued: 02/24/1976
• Est. Priority Date: 12/28/1973
• Status: Expired due to Term

• Current Assignee: Friedrichsfeld GmbH Steinzeug- und Kunststoffwerke
• Original Assignee: Friedrichsfeld GmbH Steinzeug- und Kunststoffwerke
• Inventors: Griss, Peter, Heimke, Gunther, Wachter, Paul, Heil, Herbert, Von Andrian-Werburg, Hanns
• Primary Examiner(s): Frinks, Ronald L.
• Application Number:
  US05/530,553
• Time in Patent Office: 442 Days
• Field of Search: 3/1, 3/1.9-1.913, 128/92 C, 128/92 CA, 32/10 A
• US Class Current: 623/22.36
• CPC Class Codes: A61B 17/1666 for the acetabulum
• CPC Class Codes: A61F 2/30907 Nets or sleeves applied to surface of prostheses or in cement
• CPC Class Codes: A61F 2/32 for the hip
• CPC Class Codes: A61F 2/34 Acetabular cups
• CPC Class Codes: A61F 2/36 Femoral heads ; Femoral endoprostheses
• CPC Class Codes: A61F 2/3609 Femoral heads or necks; Connections of endoprosthetic heads or necks to endoprosthetic femoral shafts A61F2/3601 takes precedence
• CPC Class Codes: A61F 2/3804 for elbows
• CPC Class Codes: A61F 2002/30158 trapezoidal
• CPC Class Codes: A61F 2002/30823 having the shape of a reverse dovetail
• CPC Class Codes: A61F 2002/3085 with a threaded, e.g. self-tapping, bone-engaging surface, e.g. external surface
• CPC Class Codes: A61F 2002/30929 having at least two superposed coatings
• CPC Class Codes: A61F 2002/3403 Polar aperture
• CPC Class Codes: A61F 2002/3631 with an integral complete or partial peripheral collar or bearing shoulder at its base
• CPC Class Codes: A61F 2002/365 Connections of heads to necks
• CPC Class Codes: A61F 2230/0026 trapezoidal
• CPC Class Codes: A61F 2310/00017 Iron- or Fe-based alloys, e.g. stainless steel
• CPC Class Codes: A61F 2310/00203 containing alumina or aluminium oxide
• CPC Class Codes: A61F 2310/00592 Coating or prosthesis-covering structure made of ceramics or of ceramic-like compounds
• CPC Class Codes: A61F 2310/00928 Coating or prosthesis-covering structure made of glass or of glass-containing compounds, e.g. of bioglass
• CPC Class Codes: A61F 2310/00934 Coating made of enamel
• CPC Class Codes: A61L 2430/24 : for joint reconstruction

Abstract

A socket for hip joint prosthesis is secured to a cavity in the bone tissue by a series of radially arranged pegs which can be projected outwardly from the wall of the socket into the surrounding tissue by a central screw member which also has a self-tapping thread which also enters the tissue.

Claims

1. A socket for hip joint prosthesis for cement free implantation comprising a body of biologically inert material provided with a semi-spherical concentric bearing cavity, a series of pegs longitudinally slidably mounted in said body in space relation to each other, a threaded screw mounted for axial movement in a concentric bore provided in said body for operative engagement with one end of each of said pegs, the threads being disposed on one end of the screw for self-tapping engagement with the tissue of the bone, a portion of the screw remote from said one end being of larger diameter than the threaded portion to define an annular shoulder, said bore having a portion of reduced diameter defining an annular shoulder for engagement with the first mentioned shoulder for assisting in holding the body in place.

2. The invention defined in claim 1, wherein all of the components are composed of dense Al₂ 0₃ ceramic.

3. The invention defined in claim 1, wherein said pegs are mounted in a series of passages radiating outwardly from said bore.

4. The invention defined in claim 3, wherein the inner ends of said pegs are provided with surfaces which are contoured for operative engagement with said screw threads during the initial rotation of said screw, said pegs being forced outwardly by engagement with said first mentioned shoulder when said threads are in engagement with bone tissue.

5. The invention defined in claim 1, wherein said body is cylindrical.