Expandable vertebral implants and methods of use

• US 20090270987A1
• Filed: 04/24/2008
• Published: 10/29/2009
• Est. Priority Date: 04/24/2008
• Status: Active Grant

• Current Assignee: Warsaw Orthopedic Incorporated (Medtronic Plc)
• Original Assignee: Warsaw Orthopedic Incorporated (Medtronic Plc)
• Inventors: Heinz, Eric Steven, Sears, William
• Granted Patent: US 8,062,368 B2
• Time in Patent Office: Days
• US Class Current: 623/17.160
• CPC Class Codes: A61B 17/70 Spinal positioners or stabilisers ; Bone stabilisers comprising fluid filler in an implant
• CPC Class Codes: A61F 2/44 for the spine, e.g. vertebrae, spinal discs
• CPC Class Codes: A61F 2/441 made of inflatable pockets or chambers filled with fluid, e.g. with hydrogel
• 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 2/4611 of spinal prostheses
• 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 2002/30131 horseshoe- or crescent- or C-shaped or U-shaped
• CPC Class Codes: A61F 2002/30133 kidney-shaped or bean-shaped
• CPC Class Codes: A61F 2002/30462 retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2002/30484 Mechanically expandable devices located on the first prosthetic part for locking into or onto the second prosthetic part
• CPC Class Codes: A61F 2002/3055 for adjusting length
• CPC Class Codes: A61F 2002/30583 filled with hardenable fluid, e.g. curable in-situ
• CPC Class Codes: A61F 2002/30586 having two or more inflatable pockets or chambers
• CPC Class Codes: A61F 2002/30601 telescopic
• CPC Class Codes: A61F 2002/30606 Sets comprising both cemented and non-cemented endoprostheses
• CPC Class Codes: A61F 2002/3082 Grooves
• CPC Class Codes: A61F 2002/30836 knurled
• CPC Class Codes: A61F 2002/30841 Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• CPC Class Codes: A61F 2002/30925 etched
• CPC Class Codes: A61F 2002/449 : comprising multiple spinal implants located in different intervertebral spaces or in different vertebrae
• CPC Class Codes: A61F 2002/4495 : having a fabric structure, e.g. made from wires or fibres
• CPC Class Codes: A61F 2002/4629 : connected to the endoprosthesis or implant via a threaded connection
• CPC Class Codes: A61F 2210/0085 : hardenable in situ, e.g. epoxy resins
• CPC Class Codes: A61F 2220/0025 : Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/0075 : sutured, ligatured or stitched, retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2230/0013 : Horseshoe-shaped, e.g. crescent-shaped, C-shaped, U-shaped
• CPC Class Codes: A61F 2230/0015 : Kidney-shaped, e.g. bean-shaped
• 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

Abstract

Illustrative embodiments disclosed herein are directed to vertebral implants and methods of use. In one embodiment, the implant includes first and second end members with an intermediate cage. The cage may be inflatable such that the implant is positionable between a collapsed state with a first reduced height to facilitate insertion between the first and second vertebral members, and an extended state with a second height greater than the first height that positions the first end member against the first vertebral member and the second end member against the second vertebral member to maintain an intervertebral axial space.

Claims

1. A vertebral implant that positions first and second vertebral members within a patient comprising:

a first end member;

a second end member;

an inflatable cage positioned between the first and second end members that includes a port that leads into an enclosed interior space adapted to contain an injectable substance, the cage including a plurality of rod portions and a plurality of crosslink members;

the cage positionable between a collapsed state with a first reduced height to facilitate insertion between the first and second vertebral members and an extended state with a second height greater than the first height that positions the first end member against the first vertebral member and the second end member against the second vertebral member to maintain an intervertebral axial space;

in the extended state, the plurality of rod portions extend between the first and second ends members and the plurality of crosslink members extend transverse to the plurality of rod portions, the plurality of rod portions and crosslink members being spaced apart by gaps and exposed within the patient.

2. The vertebral implant of claim 1, wherein the cage includes a contiguous internal volume.

3. The vertebral implant of claim 1, wherein the cage includes at least two individually inflatable sections.

4. The vertebral implant of claim 1, wherein the plurality of crosslink members are perpendicular to the plurality of rod portions.

5. The vertebral implant of claim 1, wherein the port extends through one of the first and second end members.

6. The vertebral implant 1, wherein the first end member includes at least one cavity sized to receive a section of the cage when the cage is in the extended state.

7. A vertebral implant that positions first and second vertebral members comprising:

an inflatable cage with a plurality of longitudinal members;

first and second end members positioned on opposite sides of the cage, each of the end members including a contact side that faces towards one of the first and second vertebral members and an engagement side that include cavities each sized to receive an end of one of the plurality of longitudinal members and each of the cavities including a neck and an enlarged receptacle;

the cage positionable between a collapsed state with a first reduced height to facilitate insertion between the first and second vertebral members and an extended state with a second height greater than the first height that positions the contact side of the first end member against the first vertebral member and the contact side of the second end member against the second vertebral member to maintain an intervertebral axial space;

when the cage is in the extended state the ends of the plurality of longitudinal members include an enlarged section positioned within the enlarged receptacles, the enlarged sections including a width greater than the neck and less than or equal to the receptacle.

8. The vertebral implant of claim 7, wherein the cage further includes a plurality of crosslink members that are transverse to the plurality of longitudinal members.

9. The vertebral implant of claim 7, wherein the plurality of longitudinal members includes telescoping columns arranged in an overlapping orientation.

10. The vertebral implant of claim 7, further comprising a port that extends through one of the first and second end members and into an interior section of the cage.

11. The vertebral implant of claim 10, further comprising an anchor that extends outward from the engagement side of at least one of the first and second end members and fits within an interior of the end of one of the plurality of longitudinal members.

12. The vertebral implant of claim 11, further comprising a retainer that extends around an exterior of the end of the longitudinal member to maintain the longitudinal member positioned relative to the anchor.

13. A vertebral implant that positions first and second vertebral members comprising:

an inflatable cage;

first and second end members each operatively connected to the cage and positioned on opposite sides of the cage, the end members including a first side that faces towards one of the first and second vertebral members respectively and a second side that faces the cage;

an anchor that extends outward from the second side of one of the end members and into an interior of the cage;

a port that extends through the one end member and through the anchor, the port being in communication with an interior of the cage;

the cage positionable between a collapsed state with a first reduced height to facilitate insertion between the first and second vertebral members and an extended state with a second height greater than the first height that positions the first end member against the first vertebral member and the second end member against the second vertebral member to maintain an intervertebral axial space.

14. The vertebral member of claim 13, further comprising a retainer that extends around an exterior of the cage to maintain the cage attached to the anchor.

15. The vertebral member of claim 13, further comprising a second port positioned on the other end member and in communication with the interior of the cage.

16. The vertebral implant of claim 13, wherein the cage further comprises a plurality of rods that extend between the first and second end members and a plurality of crosslink members that are transverse to the plurality of rods and spaced away from the first and second end members, the plurality of rods and plurality of crosslink members being spaced apart to form gaps therebetween.

17. The vertebral implant of claim 13, wherein the cage further comprises a plurality of longitudinal members with telescoping columns arranged in an overlapping orientation.

18. The vertebral implant of claim 13, wherein the cage includes a contiguous internal volume.

19. The vertebral implant of claim 13, wherein the cage includes at least two individually inflatable sections.

20. A method of positioning first and second vertebral members comprising:

positioning an implant between the first and second vertebral members while the implant is in a collapsed state, the implant including first and second end members and an intermediate cage;

receiving an injectable material into an interior of the cage through a first port and venting contents from the interior of the cage out through a second port; and

expanding a height of the implant to an extended state and contacting the first end member against the first vertebral member and the second end member against the second vertebral member.

21. The method of claim 20, further comprising expanding the height of the implant and forming gaps between longitudinal members that extend between the first and second end members and crosslinking members that extend transverse to the longitudinal members.

22. The method of claim 20, further comprising receiving the injectable material into an end section of the cage positioned within one of the first and second end members and enlarging the end section to maintain the cage attached to the one of the first and second end members.

23. The method of claim 20, further comprising sliding telescoping sections of the cage away from each other as the implant expands in height.