Two-piece modular patellar prosthetic system

• US 20040143336A1
• Filed: 01/22/2003
• Published: 07/22/2004
• Est. Priority Date: 01/22/2003
• Status: Abandoned Application

• Current Assignee: Zimmer Incorporated (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Zimmer Incorporated (Zimmer Biomet Holdings, Inc.)
• Inventors: Burkinshaw, Brian
• Application Number:
  US10/349,134
• Publication Number:
  US 20040143336A1
• Time in Patent Office: Days
• US Class Current: 623/20.15
• CPC Class Codes: A61F 2/3877 Patellae or trochleae
• CPC Class Codes: A61F 2002/3881 with moving parts

Abstract

A modular patellar prosthetic system used to replace a portion of the natural knee and, more particularly, a two-piece modular patellar prosthetic system having various baseplates and articulation components that are interchangeable with each other. Each baseplate has a fixation surface adapted to engage patellar bone, and each articulation component has a smooth articulation surface. The articulation component and baseplate connect with an attachment mechanism and form an implantable knee prosthesis.

Claims

1. ) A modular patellar prosthetic system adapted to replace a portion of a natural patella, the system comprising:

a baseplate having a fixation surface adapted to engage the natural patella and a bearing surface oppositely disposed from the fixation surface; and

a plurality of articulation components, each articulation component has an articulation surface adapted to articulate with a femoral component at a patello-femoral joint and a bearing surface adapted to slideably articulate with the bearing surface of the baseplate, wherein each articulation component has a different size and is adapted to attach and detach from the baseplate and is formed as a single, unitary unit.

2. ) The modular patellar prosthetic system of claim 1 wherein the articulation surfaces of the articulation components include at least two different shapes.

3. ) The modular patellar prosthetic system of claim 2 wherein at least one articulation surface has a saddle shape and at least another articulation surface has dome-shape with a generally planar surface.

4. ) The modular patellar prosthetic system of claim 1 wherein six different articulation components are provided, and three of the articulation components have an articulation surface with a saddle shape and three of the articulation components have an articulation surface other than a saddle shape.

5. ) The modular patellar prosthetic system of claim 1 wherein the baseplate is formed from a single unitary unit.

6. ) The modular patellar prosthetic system of claim 5 wherein the baseplate and one of the articulation components connect together to form a prosthetic patellar implant formed from two separate and different pieces.

7. ) The modular patellar prosthetic system of claim 6 wherein the bearing surface of the articulation component slideably rotates on the bearing surface of the baseplate while the articulation component is connected to the baseplate.

8. ) A modular patellar prosthetic system, comprising:

at least one baseplate integrally formed as a single unit and having a fixation surface adapted to engage natural patellar bone, a bearing surface oppositely disposed from the fixation surface, and an attachment mechanism located on the bearing surface; and

a plurality of articulation components, each articulation component integrally formed as a single unit and having a smooth articulation surface adapted to articulate with a femoral component at a patello-femoral joint and having a bearing surface with an attachment mechanism that is adapted to engage directly the attachment mechanism of the baseplate, wherein each articulation component can be attached and reattached to the baseplate.

9. ) The modular patellar prosthetic system of claim 8 wherein the plurality of articulation components includes at least two articulation components with different shapes and different sizes.

10. ) The modular patellar prosthetic system of claim 9 wherein one articulation component has a saddle shape and one articulation component has a shape other than a saddle shape.

11. ) The modular patellar prosthetic system of claim 10 wherein one articulation component has a dome-shape.

12. ) The modular patellar prosthetic system of claim 8 wherein the attachment mechanism on the baseplate and articulation components removeably couple together to provide modularity between the baseplate and plurality of articulation components.

13. ) The modular patellar prosthetic system of claim 8 wherein the articulation components are adapted to be connected to and removed from the baseplate while the baseplate is permanently affixed to natural patellar bone.

14. ) The modular patellar prosthetic system of claim 13 wherein the attachment mechanism on the articulation components deforms as the baseplate is connected to and removed from the articulation components.

15. ) The modular patellar prosthetic system of claim 14 wherein the attachment mechanisms on the articulation components and baseplate snap-fit together.

16. ) A modular patellar prosthetic system adapted to replace a portion of a natural patella, the system comprising:

a plurality of baseplates, each baseplate has a fixation surface adapted to affix to the natural patella and a bearing surface oppositely disposed from the fixation surface, wherein at least two baseplates are provided with different sizes; and

a plurality of articulation components, each articulation component has an articulation surface adapted to articulate with a femoral component at a patello-femoral joint and a bearing surface adapted to engage the bearing surface of the baseplates, wherein at least two articulation components are provided with different sizes and each articulation component is adapted to attach and detach from each of the baseplates.

17. ) The modular patellar prosthetic system of claim 16 wherein the articulation components are attachable and detachable from a baseplate while the baseplate is permanently affixed to the patella.

18. ) The modular patellar prosthetic system of claim 17 wherein the articulation components removeably snap-fit to the baseplates.

19. ) The modular patellar prosthetic system of claim 16 wherein the plurality of articulation components includes two articulation components with a saddle shape and two articulation components with a dome-shape.

20. ) The modular patellar prosthetic system of claim 19 wherein each articulation component has a different size.