METHOD AND APPARATUS FOR REMOVING A BEARING

• US 20110184424A1
• Filed: 04/01/2011
• Published: 07/28/2011
• Est. Priority Date: 03/07/2007
• Status: Active Grant

• Current Assignee: Biomet Manufacturing, LLC (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Biomet Manufacturing, LLC (Zimmer Biomet Holdings, Inc.)
• Inventors: Meridew, Jason D., Isch, Bryce A., Hershberger, Troy W.
• Granted Patent: US 8,048,165 B2
• Time in Patent Office: Days
• US Class Current: 606/99
• CPC Class Codes: A61F 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• 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 2/4637 for connecting or disconnecting two parts of a prosthesis
• CPC Class Codes: A61F 2002/30011 differing in porosity
• CPC Class Codes: A61F 2002/30367 with additional means for preventing said rotation
• CPC Class Codes: A61F 2002/30403 Longitudinally-oriented cooperating ribs and grooves on mating lateral surfaces of a mainly longitudinal connection
• CPC Class Codes: A61F 2002/30495 using a locking ring
• 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 2002/30822 Circumferential grooves
• CPC Class Codes: A61F 2002/30968 Sintering
• CPC Class Codes: A61F 2002/3241 having a ring, e.g. for locking the femoral head into the acetabular cup
• CPC Class Codes: A61F 2002/3611 Heads or epiphyseal parts of femur
• CPC Class Codes: A61F 2002/365 Connections of heads to necks
• CPC Class Codes: A61F 2002/4641 for disconnecting
• 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 2250/0024 made from both porous and non-porous parts, e.g. adjacent parts
• CPC Class Codes: A61F 2310/00017 Iron- or Fe-based alloys, e.g. stainless steel
• 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
• CPC Class Codes: A61F 2310/00401 : Coating made of iron, of stainless steel or of other Fe-based alloys
• CPC Class Codes: A61F 2310/00407 : Coating made of titanium or of Ti-based alloys
• CPC Class Codes: A61F 2310/00413 : Coating made of cobalt or of Co-based alloys

Abstract

A method for removing a bearing that is coupled to a prosthetic implant by a ring includes advancing a distal end of a removal tool in a first direction and into a slit formed in the ring. The ring can be caused to expand radially from engagement with the bearing. The distal end of the removal tool can be advanced in a second direction such that the removal tool engages the bearing. The distal end of the removal tool can be further advanced in the second direction such that the removal tool urges the bearing away from the prosthetic implant.

Claims

1. A method for removing a bearing that is coupled to a prosthetic implant by a ring, the method comprising:

advancing a distal end of a removal tool in a first direction into a slit formed in the ring such that the ring expands radially from engagement with the bearing at a locked position to an unlocked position;

advancing the distal end of the removal tool in a second direction such that the removal tool engages the bearing; and

continuing the advancing of the distal end of the removal tool in the second direction such that the removal tool urges the bearing away from the prosthetic implant.

2. The method of claim 1 wherein advancing the distal end of the removal tool in the first direction further comprises:

slidably advancing a pair of converging sloped surfaces formed on the distal end of the removal tool along opposing surfaces of the ring at the slit.

3. The method of claim 2 wherein advancing the distal end of the removal tool in the second direction further comprises:

moving an engagement lip formed on the distal end of the removal tool into contact with an underside surface of the bearing.

4. The method of claim 3 wherein further advancing the distal end of the removal tool in the second direction further comprises:

imparting a force onto the underside of the bearing with the engagement lip.

5. The method of claim 1 wherein the first and second directions are opposite.

6. The method of claim 1 wherein advancing the distal end of the removal tool further comprises:

locating the distal end of the removal tool into a slot formed on an upper rim of the prosthetic implant and onto a ramped surface formed on the prosthetic implant.

7. The method of claim 6, wherein the removal tool includes a shaft that extends at an angle relative to the distal end, the method further comprising:

rotating the removal tool along an axis of the shaft such that a prying action is imparted onto the bearing.

8. The method of claim 1 wherein the prosthetic implant comprises an acetabular cup.

9. The method of claim 1 wherein the prosthetic implant comprises a humeral tray.

10. A method for removing a bearing that is coupled to a prosthetic implant by a ring, the method comprising:

advancing a distal end of a removal tool in a first direction into a slit formed in the ring such that converging ramped surfaces on the distal end of the removal tool engage and expand the ring radially from engagement with the bearing at a locked position to an unlocked position;

further advancing the distal end of the removal tool in the first direction to position at least a portion of the distal end of the removal tool into a slot formed on an upper rim of the prosthetic implant at a location beneath the ring;

advancing the distal end of the removal tool in a second direction such that the removal tool engages the bearing; and

continuing the advancing of the distal end of the removal tool in the second direction such that the removal tool urges the bearing away from the prosthetic implant.

11. The method of claim 10 wherein advancing the distal end of the removal tool in the second direction further comprises:

moving an engagement lip formed on the distal end of the removal tool into contact with an underside surface of the bearing.

12. The method of claim 11 wherein further advancing the distal end of the removal tool in the second direction further comprises:

imparting a force onto the underside of the bearing with the engagement lip.

13. The method of claim 10 wherein the first and second directions are opposite.

14. The method of claim 10 wherein advancing the distal end of the removal tool further comprises:

locating the distal end of the removal tool onto a ramped surface formed on the prosthetic implant and leveraging the tool against the ramped surface of the prosthetic implant while engaging the bearing.

15. The method of claim 14, wherein the removal tool includes a shaft that extends at an angle relative to the distal end, the method further comprising:

rotating the removal tool along an axis of the shaft such that a prying action is imparted onto the bearing.

16. The method of claim 10 wherein the prosthetic implant comprises an acetabular cup.

17. The method of claim 10 wherein the prosthetic implant comprises a humeral tray.

18. A method for removing a bearing that is coupled to a prosthetic implant by a ring, the method comprising:

advancing a distal end of a removal tool in a first direction and into engagement with opposing surfaces of the ring;

slidably advancing converging ramped surfaces on the distal end of the removal tool along the opposing surfaces of the ring such that the ring is expanded radially from engagement with the bearing at a locked position to an unlocked position;

further advancing the distal end of the removal tool in the first direction to position at least a portion of the distal end of the removal tool into a slot formed on an upper rim of the prosthetic implant at a location beneath the ring;

moving the distal end of the removal tool into engagement with the bearing; and

retracting the distal end of the removal tool from the slot such that the removal tool urges the bearing away from the prosthetic implant.

19. The method of claim 18 wherein moving the distal end of the removal tool further comprises:

moving an engagement lip formed on the distal end of the removal tool into contact with an underside surface of the bearing; and

imparting a force onto the underside of the bearing with the engagement lip.

20. The method of claim 18 wherein the prosthetic implant comprises one of an acetabular cup and humeral bearing.