Bone supporting devices with bio-absorbable end members

• US 8,062,365 B2
• Filed: 08/04/2003
• Issued: 11/22/2011
• Est. Priority Date: 08/04/2003
• Status: Active Grant

• Current Assignee: Warsaw Orthopedic Incorporated (Medtronic Plc)
• Original Assignee: Warsaw Orthopedic Incorporated (Medtronic Plc)
• Inventors: Schwab, Frank J.
• Primary Examiner(s): Robert; Eduardo C
• Assistant Examiner(s): Hoffman; Mary
• Application Number:
  US10/633,901
• Publication Number:
  US 20050033425A1
• Time in Patent Office: 3,032 Days
• Field of Search: 623 1711- 1716
• US Class Current: 623/17.11
• CPC Class Codes: A61F 2/2846 Support means for bone substitute or for bone graft implants, e.g. membranes or plates for covering bone defects nets or sleeves applied to surface of endoprostheses A61F2/30907; bone plates A61B17/80; bone regeneration in dental surgery A61C8/0006
• 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 2/30744 End caps, e.g. for closing an endoprosthetic cavity
• CPC Class Codes: A61F 2/4465 having a circular or kidney shaped cross-section substantially perpendicular to the axis of the spine
• CPC Class Codes: A61F 2002/2817 Bone stimulation by chemical reactions or by osteogenic or biological products for enhancing ossification, e.g. by bone morphogenetic or morphogenic proteins [BMP] or by transforming growth factors [TGF]
• CPC Class Codes: A61F 2002/2835 Bone graft implants for filling a bony defect or an endoprosthesis cavity, e.g. by synthetic material or biological material
• CPC Class Codes: A61F 2002/30062 (bio)absorbable, biodegradable, bioerodable, (bio)resorbable, resorptive
• CPC Class Codes: A61F 2002/30125 elliptical or oval
• CPC Class Codes: A61F 2002/30133 kidney-shaped or bean-shaped
• CPC Class Codes: A61F 2002/30153 rectangular
• CPC Class Codes: A61F 2002/3023 wedge-shaped cylinders
• CPC Class Codes: A61F 2002/30235 tubular, e.g. sleeves
• CPC Class Codes: A61F 2002/30593 hollow
• CPC Class Codes: A61F 2002/30622 Implant for fusing a joint or bone material
• CPC Class Codes: A61F 2002/30677 Means for introducing or releasing pharmaceutical products, e.g. antibiotics, into the body
• CPC Class Codes: A61F 2002/30784 Plurality of holes
• CPC Class Codes: A61F 2002/30841 Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• CPC Class Codes: A61F 2002/30919 Sleeves
• CPC Class Codes: A61F 2210/0004 bioabsorbable
• CPC Class Codes: A61F 2230/0008 elliptical or oval
• CPC Class Codes: A61F 2230/0015 : Kidney-shaped, e.g. bean-shaped
• CPC Class Codes: A61F 2230/0019 : rectangular
• CPC Class Codes: A61F 2230/0069 : cylindrical
• CPC Class Codes: A61F 2310/00011 : Metals or alloys
• CPC Class Codes: A61F 2310/00179 : Ceramics or ceramic-like structures
• CPC Class Codes: A61F 2310/00329 : Glasses, e.g. bioglass
• CPC Class Codes: A61F 2310/00365 : Proteins; Polypeptides; Degradation products thereof

Abstract

A device for supporting adjacent bony portions includes a body having a first end and an opposite second end. The body is positionable in a space between the adjacent bony portions with the first and second ends oriented toward respective ones of the adjacent bony portions. At least one of the first and second ends includes bone engaging surfaces. An end member substantially covers the bone engaging surfaces with a bio-absorbable material on at least one end of the body. The end member providing a smooth surface profile to facilitate insertion of the body in the space between the adjacent bony portions.

Claims

1. A device for supporting adjacent bony portions, comprising:

a body having a first end and an opposite second end, said body positionable in a space between the adjacent bony portions with said first and second ends oriented toward respective ones of the adjacent bony portions, wherein said body includes an outer surface and an opposite inner surface adjacent at least one of said first and second ends and said at least one of said first and second ends including bone engaging surfaces thereon, said bone engaging surfaces being separated from one another by recesses located therebetween that extend between said inner and outer surfaces of said body; and

an end member around said at least one of said first and second ends, said end member substantially covering said bone engaging surfaces with a smooth surface profile between said bone engaging surfaces to facilitate insertion of said body in the space between the adjacent bony portions wherein said end member extends from said bone engaging surfaces at said at least one of said first and second ends and along said inner and outer surfaces of said body toward the other of said first and second ends, wherein said end member is configured with respect to said body to prevent said bone engaging surfaces from engaging the respective adjacent bony portion during movement of said body into the space between the adjacent bony portions, and further wherein said end member is composed of material that degrades over time to permit the adjacent bony portions to settle toward said at least one of said first and second ends to position said bone engaging surfaces thereof in engagement with the respective adjacent bony portion.

2. The device according to claim 1, wherein said bone engaging surfaces on said at least one end engage the adjacent bony portion when said end member is substantially degraded.

3. The device according to claim 1, wherein said body includes a hollow chamber extending between said first and second ends.

4. The device of claim 3, further comprising bone growth material in said chamber.

5. The device of claim 3, wherein said chamber is defined by said inner surface of said body, said end member extending at least partially into said chamber.

6. The device of claim 1, wherein said bone engaging surfaces include discontinuities therebetween, said end member occupying said discontinuities to provide said smooth surface profile.

7. The device of claim 1, wherein said body includes a wall, said wall including a plurality of openings therethrough in communication with a hollow chamber in said body, said hollow chamber extending between said first end and said second end.

8. The device of claim 7, wherein said end member extends about said chamber.

9. The device of claim 7, wherein said end member is a continuous ring extending about said at least one of said first end and said second end, said end member including a central opening in communication with said chamber.

10. The device according to claim 7, wherein said wall is comprised of a mesh structure.

11. The device of claim 7, wherein said end member provides an end surface that encloses said chamber.

12. The device of claim 1, wherein the other of said first and second ends includes bone engaging surfaces and further comprising a second end member around said other end, said second end member substantially covering said bone engaging surfaces on said other end with a bio-absorbable material and providing a smooth surface profile to facilitate insertion of said body in the space between the adjacent bony portions.

13. The device according to claim 12, wherein said bone engaging surfaces on each of said first and second ends engage the adjacent bony portion when said end members are substantially degraded.

14. The device according to claim 12, wherein said body includes a hollow chamber extending between said first and second ends, each of said end members extending about said chamber.

15. The device of claim 12, wherein said bone engaging surfaces at each of said first and second ends include discontinuities therebetween, each of said end members occupying said discontinuities to provide said smooth surface profile.

16. The device of claim 12, wherein each of said end members forms a continuous ring about said end of said body.

17. The device of claim 12, wherein said body includes a first height between said first and second ends and a second height between outer ends of said end members, said second height being greater than said first height.

18. The device of claim 1, wherein said body includes a cross-sectional shape between said first and second ends selected from the group consisting of:

a circular shape, an oval shape, a kidney shape, and a boomerang shape.

19. The device of claim 1, wherein said end member extends along substantially the entire length of said body between said first and second ends.

20. The device of claim 1, wherein said end member includes a number of end member portions substantially covering respective ones of said bone engaging surfaces, said end member portions being spaced from one another about said at least one of said first and second ends.