Prosthesis with orientable bearing surface

• US 5,489,311 A
• Filed: 01/21/1994
• Issued: 02/06/1996
• Est. Priority Date: 01/21/1994
• Status: Expired due to Term

• Current Assignee: Joint Medical Products Corp. (Johnson & Johnson)
• Original Assignee: Joint Medical Products Corp. (Johnson & Johnson)
• Inventors: Cipolletti, George B.
• Primary Examiner(s): ISABELLA, DAVID J
• Application Number:
  US08/184,274
• Time in Patent Office: 746 Days
• Field of Search: 623/16, 623/18, 623/20, 606/86, 606/87, 606/88, 606/99
• US Class Current: 623/20.34
• CPC Class Codes: A61F 2/389 Tibial components A61F2/3868 takes precedence
• CPC Class Codes: A61F 2/461 of knees
• CPC Class Codes: A61F 2/4637 for connecting or disconnecting two parts of a prosthesis
• CPC Class Codes: A61F 2/4684 Trial or dummy prostheses
• CPC Class Codes: A61F 2002/30143 hexagonal
• CPC Class Codes: A61F 2002/30217 hollow cones, e.g. tubular-like cones
• CPC Class Codes: A61F 2002/30233 Stepped cylinders, i.e. having discrete diameter changes
• CPC Class Codes: A61F 2002/30332 Conically- or frustoconically-shaped protrusion and recess
• CPC Class Codes: A61F 2002/30433 using additional screws, bolts, dowels, rivets or washers e.g. connecting screws
• CPC Class Codes: A61F 2002/30487 Circumferential cooperating grooves and beads on cooperating lateral surfaces of a mainly longitudinal connection
• CPC Class Codes: A61F 2002/305 Snap connection
• CPC Class Codes: A61F 2002/3054 about a connection axis or implantation axis for selecting any one of a plurality of radial orientations between two modular parts, e.g. Morse taper connections, at discrete positions, angular positions or continuous positions
• CPC Class Codes: A61F 2002/30604 modular
• CPC Class Codes: A61F 2002/30617 Visible markings for adjusting, locating or measuring
• CPC Class Codes: A61F 2002/30904 serrated profile, i.e. saw-toothed
• CPC Class Codes: A61F 2002/4619 for extraction
• CPC Class Codes: A61F 2002/4641 for disconnecting
• CPC Class Codes: A61F 2220/0025 Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/0033 made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2220/0041 using additional screws, bolts, dowels or rivets, e.g. connecting screws
• CPC Class Codes: A61F 2230/0017 : Angular shapes
• CPC Class Codes: A61F 2230/0067 : conical
• CPC Class Codes: A61F 2230/0069 : cylindrical
• CPC Class Codes: A61F 2250/0097 : Visible markings, e.g. indicia
• CPC Class Codes: A61F 2310/00023 : Titanium or titanium-based alloys, e.g. Ti-Ni alloys
• CPC Class Codes: A61F 2310/00029 : Cobalt-based alloys, e.g. Co-Cr alloys or Vitallium

Abstract

A prosthesis (13) for implantation in a patient'"'"'s bone (2) is provided which has a metal fixation member (10), a metal orienting member (20) secured to the fixation member (10) by a self-locking taper (15,24), and a plastic bearing (30) which is secured to the orienting member (20) in a predetermined orientation. By means of this structure, the plastic bearing (30) can be given a desired orientation with regard to the metal fixation member (10) independent of the orientation of the fixation member (10) with respect to the patient'"'"'s bone (2). Also, replacement and/or reorientation of the bearing (30) are facility. The prosthesis (13) can be used to form the tibial component of an artificial knee joint.

Claims

1. A prosthesis for implantation in a bone, said prosthesis having a bearing surface and comprising a first member for implantation in the bone, a second member which mates with the first member through a self-locking taper, and a third member which carries the bearing surface, wherein:

(a) the first member has a bore, a portion of which forms a female part of the self-locking taper;

(b) the second member has an outer surface a portion of which forms a male part of the self-locking taper, said second member;

(i) being receivable in the bore of the first member; and

(ii) including means for rotating the second member within the bore of the first member prior to locking engagement of the self locking taper; and

(c) the third member has means for engaging the second member in a predetermined angular orientation relative to the second member and for preventing the third member from rotating relative to the second member.

2. The prosthesis of claim 1 wherein the second member includes a bore having a female thread formed therein for removing the second member from the first member.

3. The prosthesis of claim 1 further comprising a screw for securing the second member to the first member.

4. The prosthesis of claim 3 wherein the second member includes a bore and the screw is received within the bore.

5. The prosthesis of claim 1 wherein the third member'"'"'s means for engaging and preventing rotation engages the second member'"'"'s means for rotating.

6. A system comprising the prosthesis of claim 1 and an apparatus for implanting the prosthesis, said apparatus comprising:

means for indicating the angular orientation of the second member relative to the first member; and

means for releasably engaging the means for rotating the second member.

7. The system of claim 6 wherein the means for indicating and the means for releasably engaging are rotatably mounted on a drive member for locking the engagement of the self-locking taper.

8. The system of claim 6 wherein the means for indicating and the means for releasably engaging comprise a unitary element which is rotatably mounted on a drive means for locking the self-locking taper.