Expandable fusion device and method of installation thereof

• US 8,845,732 B2
• Filed: 06/25/2012
• Issued: 09/30/2014
• Est. Priority Date: 09/03/2010
• Status: Active Grant

• Current Assignee: Globus Medical, Inc.
• Original Assignee: Globus Medical, Inc.
• Inventors: Weiman, Mark
• Primary Examiner(s): MERENE, JAN CHRISTOP L
• Application Number:
  US13/531,943
• Publication Number:
  US 20120330422A1
• Time in Patent Office: 827 Days
• Field of Search: 606/99, 606/94, 606/279, 623 1711- 1712
• US Class Current: 623/17.15
• CPC Class Codes: A61F 2/441 made of inflatable pockets or chambers filled with fluid, e.g. with hydrogel
• CPC Class Codes: A61F 2/442 Intervertebral or spinal discs, e.g. resilient non-disc-shaped intervertebral inflatable pockets A61F2/441; non-disc-shaped intervertebral fusion implants A61F2/4455
• CPC Class Codes: A61F 2/4455 for the fusion of spinal bodies, e.g. intervertebral fusion of adjacent spinal bodies, e.g. fusion cages intervertebral discs A61F2/442
• 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 2/447 substantially parallelepipedal, e.g. having a rectangular or trapezoidal cross-section
• 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 2002/30266 wedge-shaped parallelepipeds
• CPC Class Codes: A61F 2002/30387 Dovetail connection
• CPC Class Codes: A61F 2002/30405 made by screwing complementary threads machined on the parts themselves
• CPC Class Codes: A61F 2002/30411 having two threaded end parts connected by a threaded central part with opposite threads at its opposite ends, i.e. for adjusting the distance between both end parts by rotating the central part
• CPC Class Codes: A61F 2002/30471 connected by a hinged linkage mechanism, e.g. of the single-bar or multi-bar linkage type
• CPC Class Codes: A61F 2002/30482 using a locking cam
• 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 2002/30495 using a locking ring
• CPC Class Codes: A61F 2002/30517 using a locking plate
• CPC Class Codes: A61F 2002/30522 releasable, e.g. using a releasable ratchet
• CPC Class Codes: A61F 2002/30523 by means of meshing gear teeth
• CPC Class Codes: A61F 2002/30556 for adjusting thickness
• CPC Class Codes: A61F 2002/30558 : Force-limiting means
• CPC Class Codes: A61F 2002/30579 : with mechanically expandable devices, e.g. fixation devices
• CPC Class Codes: A61F 2002/30593 : hollow
• CPC Class Codes: A61F 2002/30601 : telescopic
• CPC Class Codes: A61F 2002/30828 : parallel
• CPC Class Codes: A61F 2002/30841 : Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• CPC Class Codes: A61F 2002/30843 : Pyramidally-shaped
• CPC Class Codes: A61F 2002/30904 : serrated profile, i.e. saw-toothed
• CPC Class Codes: A61F 2002/4662 : for measuring penetration depth
• CPC Class Codes: A61F 2310/00011 : Metals or alloys
• 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 2310/00179 : Ceramics or ceramic-like structures

Abstract

The present invention provides an expandable fusion device capable of being installed inside an intervertebral disc space to maintain normal disc spacing and restore spinal stability, thereby facilitating an intervertebral fusion. In one embodiment, the fusion device includes a central ramp, a first endplate, and a second endplate, the central ramp capable of being moved in a first direction to move the first and second endplates outwardly and into an expanded configuration. The fusion device is capable of being deployed down an endoscopic tube.

Claims

1. A system for intervertebral fusion comprising:

a dilator having a proximal end and a tapered distal end for penetrating soft tissue;

a cannula having a proximal end and a distal end; and

an intervertebral implant sized for insertion into an intervertebral space through the cannula, wherein the intervertebral implant comprises a first endplate, a second endplate, and a central ramp disposed between the first endplate and the second endplate, wherein the central ramp is configured to move in a first direction and cause the first and second endplates to move outwardly and away from one another,

a driving ramp disposed between the first endplate and the second endplate at an opposite end of the intervertebral implant from the central ramp, wherein the driving ramp has a longitudinal through bore, wherein the driving ramp is configured to engage ramped surfaces of the first endplate and ramped surfaces of the second endplate; and

an actuation member comprising a head portion and an actuation member extension that extends through an unthreaded opening in a longitudinal through bore of the driving ramp to be received within an opening in the central ramp extension, wherein rotational movement of the actuation member in the first direction pulls the central ramp towards the driving ramp;

wherein when the actuation member is rotated, the driving ramp is fixed with respect to the actuation member and the central ramp is moved in either the first direction or a second direction.

2. The system of claim 1, wherein the cannula has a diameter of less than 10 millimeters.

3. The system of claim 1, wherein the cannula comprises an elongated cylindrical body, the elongated cylindrical body having flattened outer surfaces at the distal end of the cannula.

4. The system of claim 1, further comprising a connection assembly in the general shape of a collar, wherein the cannula comprises notches at the proximal end for attachment to the connection assembly.

5. The system of claim 4, further comprising a funnel configured for attachment to the connection assembly.

6. The system of claim 4, further comprising a fluid adapter configured for attachment to the connection assembly.

7. The system of claim 1, wherein first endplate comprises a first end, a second end, an upper surface connecting the first end and the second end, first ramped surfaces on either side of the first endplate proximate the first end, second ramped surfaces on either side of the first endplate proximate the second end, and wherein the second endplate comprises a first end, a second end, an upper surface connecting the first end and the second end, first ramped surfaces on either side of the second endplate proximate the first end, second ramped surfaces on either side of the second endplate proximate the second end.

8. The system of claim 7, wherein, when the intervertebral implant is in an unexpanded configuration, the first ramped surfaces of the first endplate and the first ramped surfaces of the second endplate overlap, and the second ramped surfaces of the first endplate and the second ramped surfaces of the second endplate overlap.

9. The system of claim 7, wherein the first endplate further comprises a central ramped surface disposed between the first and second ramped surfaces of the first endplate, wherein the second endplate further comprises a central ramped surface disposed between the first and second ramped surfaces of the second endplate, and wherein the central ramped surface of the first endplate and wherein the central ramped surface of the second endplate are configured to engage the central ramp.

10. The system of claim 7, wherein, when the intervertebral implant is in an unexpanded configuration, the first ramped surfaces of the first endplate overlap the first ramped surfaces of the second endplate, and the second ramped surfaces of the second endplate overlap the second ramped surfaces of the first endplate.

11. The system of claim 7, wherein, when the intervertebral implant is in an unexpanded configuration, one of the first ramped surfaces of the first endplate overlaps one of the first ramped surfaces of the second endplate, and another one of the first ramped surfaces of the second endplate overlaps another one of the first ramped surfaces of the second endplate.

12. The system of claim 7, wherein the central ramp comprises a ramped expansion portion at one end of the intervertebral implant and a central ramp extension extending from the expansion portion, wherein the central ramp is configured to engage the first endplate and the second endplate.

13. A system for intervertebral fusion comprising:

a dilator having a proximal end and a tapered distal end for penetrating soft tissue;

a cannula having a proximal end and a distal end; and

an intervertebral implant sized for insertion into an intervertebral space through the cannula, wherein the intervertebral implant comprises;

a first endplate comprising a first end, a second end, an upper surface connecting the first end and the second end, first ramped surfaces on either side of the first endplate proximate the first end, second ramped surfaces on either side of the first endplate proximate the second end;

a second endplate comprising a first end, a second end, an upper surface connecting the first end and the second end, first ramped surfaces on either side of the second endplate proximate the first end, second upper surfaces on either side of the second endplate proximate the second end, wherein, when the intervertebral implant is in an unexpanded configuration, the first ramped surfaces of the first endplate and the first ramped surfaces of the second endplate overlap, and the second ramped surfaces of the first endplate and the second ramped surfaces of the second endplate overlap;

a central ramp disposed between the first endplate and the second endplate, wherein the central ramp is configured to engage the first ramped surfaces of the first endplate and the first ramped surfaces of the second endplate;

a driving ramp disposed between the first endplate and the second endplate at an opposite end of the intervertebral implant from the expansion portion of the central ramp, wherein the driving ramp has a longitudinal through bore, wherein the driving ramp is configured to engage the second ramped surfaces of the first endplate and the second ramped surfaces of the second endplate; and

an actuation member comprising a head portion and an actuation member extension that extends through the longitudinal through bore of the driving ramp to be received within an opening in the central ramp extension, wherein rotational movement of the actuation member in the first direction pulls the central ramp and the driving ramp towards one another, thereby moving the first and second endplates outwardly and away from one another

wherein when the actuation member is rotated, the driving ramp is fixed with respect to the actuation member.

14. The system of claim 13, wherein the cannula comprises an elongated cylindrical body, the elongated cylindrical body having flattened outer surfaces at the distal end of the cannula.

15. The system of claim 13, wherein the ramped expansion portion comprises one or more upwardly facing ramped surfaces configured to engage the corresponding first ramped surfaces of the first endplate, and wherein the ramped expansion portion comprises one or more downwardly facing ramped surfaces configured to engage the corresponding first ramped surfaces of the second endplate.

16. A system for intervertebral fusion comprising:

a dilator having a proximal end and a tapered distal end for penetrating soft tissue;

a cannula having a proximal end and a distal end; and

an intervertebral implant sized for insertion into an intervertebral space through the cannula, wherein the intervertebral implant comprises;

a first endplate comprising a first end, a second end, an upper surface connecting the first end and the second end, first ramped surfaces on either side of the first endplate proximate the first end, second ramped surfaces on either side of the first endplate proximate the second end, and a central ramped surface disposed between the first and second ramped surfaces;

a second endplate comprising a first end, a second end, an upper surface connecting the first end and the second end, first ramped surfaces on either side of the second endplate proximate the first end, second ramped surfaces on either side of the second endplate proximate the second end, and a central ramped surface disposed between the first and second ramped surfaces;

a central ramp disposed between the first endplate and the second endplate, wherein the central ramp comprises a ramped expansion portion at one end of the intervertebral implant and a central ramp extension extending from the expansion portion, wherein the ramped expansion portion is configured to engage the first ramped surfaces of the first endplate and the first ramped surfaces of the second endplate, and wherein the central ramp extension comprises ramped surfaces projecting from the central ramp extension and configured to engage the central ramped surface of the first endplate and the central ramped surface of the second endplate;

a driving ramp disposed between the first endplate and the second endplate at an opposite end of the intervertebral implant from the expansion portion of the central ramp, wherein the driving ramp has a longitudinal through bore, wherein the driving ramp is configured to engage the second ramped surfaces of the first endplate and the second ramped surfaces of the second endplate; and

an actuation member comprising a head portion and an actuation member extension that extends through the longitudinal through bore of the driving ramp to be received within an opening in the central ramp extension, wherein rotational movement of the actuation member in the first direction pulls the central ramp and the driving ramp towards one another.

17. The system of claim 16, wherein the cannula comprises an elongated cylindrical body, the elongated cylindrical body having flattened outer surfaces at the distal end of the cannula.

18. The system of claim 16, wherein the ramped surfaces of the central ramp extension comprise an upwardly facing ramped surface projecting from the central ramped extension, the upwardly facing ramped surface being configured to engage the central ramped surface of the second endplate, and a downwardly facing ramped surface projecting from the central ramped extension, the downwardly facing ramped surface being configured to engage central ramped surface of the first endplate.