Joint prosthesis with positionable head

• US 20070078519A1
• Filed: 09/30/2005
• Published: 04/05/2007
• Est. Priority Date: 09/30/2005
• Status: Active Grant

• Current Assignee: Depuy Synthes Products Incorporated (Johnson & Johnson)
• Original Assignee: DePuy Synthes Products LLC (Johnson & Johnson)
• Inventors: Klotz, Conrad
• Granted Patent: US 8,679,185 B2
• Time in Patent Office: Days
• US Class Current: 623/23.470
• CPC Class Codes: A61F 2/30734 Modular inserts, sleeves or augments, e.g. placed on proximal part of stem for fixation purposes or wedges for bridging a bone defect
• CPC Class Codes: A61F 2/40 for shoulders
• CPC Class Codes: A61F 2/4014 Humeral heads or necks; Connections of endoprosthetic heads or necks to endoprosthetic humeral shafts
• CPC Class Codes: A61F 2/4059 Humeral shafts
• CPC Class Codes: A61F 2002/30329 Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2002/30332 Conically- or frustoconically-shaped protrusion and recess
• CPC Class Codes: A61F 2002/30378 Spherically-shaped protrusion and recess
• CPC Class Codes: A61F 2002/30538 for adjusting angular orientation
• 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 2002/30772 Apertures or holes, e.g. of circular cross section
• CPC Class Codes: A61F 2002/30884 Fins or wings, e.g. longitudinal wings for preventing rotation within the bone cavity
• CPC Class Codes: A61F 2002/4018 Heads or epiphyseal parts of humerus
• CPC Class Codes: A61F 2002/4029 Necks
• CPC Class Codes: A61F 2002/4037 Connections of heads to necks
• CPC Class Codes: A61F 2002/4044 Connections of necks to shafts
• CPC Class Codes: A61F 2002/4062 Proximal or metaphyseal parts of shafts
• 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 2250/0006 for adjusting angular orientation

Abstract

A prosthesis for a joint includes a stem for engagement with a bone. The stem includes a surface defining a bore. The prosthesis further includes a joint component. The joint component includes a bearing surface for articulating engagement with at least one of a natural opposing joint component and a prosthetic opposing joint component. The prosthesis further includes a mounting element. The mounting element includes a proximal portion for engagement with the joint component and further includes a substantially solid articulating portion having a contiguous periphery. The substantially solid articulating portion is configured to facilitate articulating movement of the substantially solid articulating portion within the bore when the contiguous periphery is not forcefully engaged with the bore, and the substantially solid articulating portion and the bore are configured to fixedly couple the mounting element to the stem when the contiguous periphery is forcefully engaged with the bore.

Claims

1. A prosthesis for ajoint associated with a bone and at least one of a natural opposing joint component and a prosthetic opposing joint component, the prosthesis comprising:

a stem for engagement with the bone, said stem including a surface defining a bore;

a joint component including a bearing surface for articulating engagement with at least one of the natural opposing joint component and the prosthetic opposing joint component; and

a mounting element including a proximal portion for engagement with said joint component and further including a substantially solid articulating portion having a contiguous periphery;

wherein said substantially solid articulating portion is configured to facilitate articulating movement of said substantially solid articulating portion within said bore when said contiguous periphery is not forcefully engaged with said bore, and said substantially solid articulating portion and said bore are configured to fixedly couple said mounting element to said stem when said contiguous periphery is forcefully engaged with said bore.

2. The prosthesis of claim 1, wherein said substantially solid articulating portion includes a spheroidal surface for contacting said bore to permit movement of said mounting element in multiple degrees of freedom.

3. The prosthesis of claim 2, wherein said spheroidal surface is frusto-spherical.

4. The prosthesis of claim 3, wherein said bore includes a substantially uniformly tapered surface contacting said frusto-spherical surface of said substantially solid articulating portion.

5. The prosthesis of claim 4, wherein said bore and said substantially solid articulating portion are configured such that frictional engagement between said bore and said substantially solid articulating portion serves to fix orientation of said mounting element relative to said stem.

6. The prosthesis of claim 1, wherein said substantially solid articulating portion and said bore are configured to facilitate seating said substantially solid articulating portion within said bore in any of a plurality of positions to which said substantially solid articulating portion can be moved relative to said bore.

7. The prosthesis of claim 6, wherein said bore and said substantially solid articulating portion are configured such that frictional engagement between said bore and said substantially solid articulating portion serves to fix orientation of said mounting element relative to said stem.

8. The prosthesis of claim 7, wherein said joint component and said proximal portion of said mounting element define a socket taper interface for engagement of said joint component to said mounting element.

9. The prosthesis of claim 1, wherein said joint component and said proximal portion of said mounting element define a socket taper interface for engagement of said joint component to said mounting element.

10. A prosthesis for association with a mating component of a joint, the prosthesis comprising:

a stem including a bone engagement portion and a surface for facing the mating component of the joint, said surface defining a tapered bore;

a head component including a bearing surface for articulation with the mating component of the joint; and

a mounting element including a proximal portion configured for engagement with said head component and further including a substantially solid articulating portion defining a spheroidal bearing surface sized to be received within said tapered bore and to form a friction-fit engagement with said tapered bore when said substantially solid articulating portion is forced into said tapered bore, said engagement being substantially contiguous along a portion of the spheroidal bearing surface defining a great circle.

11. The prosthesis of claim 10, wherein the spheroidal bearing surface is frusto-spherical.

12. A method for mounting a joint component to a bone, the method comprising:

inserting a stem into the bone;

positioning a substantially solid articulating portion of a mounting element within a tapered bore defined by the stem so that the mounting element is substantially free to rotate in multiple degrees of freedom relative to the stem while maintaining substantially contiguous engagement between an elliptical portion of a surface of the tapered bore and a portion of a surface of the substantially solid articulating portion defining a great circle;

engaging the joint component to a proximal portion of the mounting element;

manipulating the mounting element to vary an angular position of the joint component relative to the stem; and

forcing the substantially solid articulating portion into the tapered bore to fix a position of the mounting element relative to the stem.

13. The method of claim 12, wherein said forcing step includes press-fitting the substantially solid articulating portion into the tapered bore.

14. The method of claim 13, wherein said press-fitting is limited to press-fitting the substantially solid articulating portion into the tapered bore by hand.