Expandable articulating intervertebral implant with limited articulation

• US 8,147,550 B2
• Filed: 05/20/2005
• Issued: 04/03/2012
• Est. Priority Date: 08/05/2003
• Status: Active Grant

• Current Assignee: Flexuspine Incorporated
• Original Assignee: Flexuspine Incorporated
• Inventors: Gordon, Charles R., Harbold, Corey T., Hanson, Heather S.
• Primary Examiner(s): Sweet, Thomas J
• Assistant Examiner(s): Prone, Christopher D
• Application Number:
  US11/134,079
• Publication Number:
  US 20050283247A1
• Time in Patent Office: 2,510 Days
• Field of Search: None
• US Class Current: 623/17.15
• CPC Class Codes: A61B 17/7005 Parts of the longitudinal elements, e.g. their ends, being specially adapted to fit in the screw or hook heads
• CPC Class Codes: A61B 17/7007 Parts of the longitudinal elements, e.g. their ends, being specially adapted to fit around the screw or hook heads
• CPC Class Codes: A61B 17/7008 with parts of, or attached to, the longitudinal elements, bearing against an outside of the screw or hook heads, e.g. nuts on threaded rods A61B17/7007 takes precedence
• CPC Class Codes: A61B 17/701 Longitudinal elements with a non-circular, e.g. rectangular, cross-section A61B17/7005, A61B17/7007 take precedence
• CPC Class Codes: A61B 17/7023 with a pivot joint
• CPC Class Codes: A61B 17/7032 Screws or hooks with U-shaped head or back through which longitudinal rods pass
• CPC Class Codes: A61B 17/7037 wherein pivoting is blocked when the rod is clamped
• CPC Class Codes: A61B 17/7064 Devices acting on, attached to, or simulating the effect of, vertebral facets; Tools therefor
• CPC Class Codes: A61B 17/80 Cortical plates , i.e. bone plates; Instruments for holding or positioning cortical plates, or for compressing bones attached to cortical plates
• CPC Class Codes: A61B 17/86 Pins or screws or threaded wires; nuts therefor A61B17/72 take precedence
• CPC Class Codes: A61F 2/30767 Special external or bone-contacting surface, e.g. coating for improving bone ingrowth
• CPC Class Codes: A61F 2/4405 for apophyseal or facet joints, i.e. between adjacent spinous or transverse processes devices implanted between spinous or transverse processes A61B17/7062
• CPC Class Codes: A61F 2/4425 made of articulated components
• 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 2/4611 of spinal prostheses
• 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 2002/30092 using shape memory or superelastic materials, e.g. nitinol
• 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 2002/30225 Flat cylinders, i.e. discs
• CPC Class Codes: A61F 2002/3023 : wedge-shaped cylinders
• CPC Class Codes: A61F 2002/30235 : tubular, e.g. sleeves
• CPC Class Codes: A61F 2002/30331 : made by longitudinally pushing a protrusion into a complementarily-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2002/30365 : with additional means for limiting said rotation
• CPC Class Codes: A61F 2002/30369 : Limited lateral translation of the protrusion within a larger recess
• CPC Class Codes: A61F 2002/30383 : made by laterally inserting a protrusion, e.g. a rib into a complementarily-shaped groove
• CPC Class Codes: A61F 2002/30462 : retained or tied with a rope, string, thread, wire or cable
• 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 2002/30476 : locked by an additional locking mechanism
• CPC Class Codes: A61F 2002/30492 : using a locking pin
• CPC Class Codes: A61F 2002/305 : Snap connection
• CPC Class Codes: A61F 2002/30505 : spring biased
• CPC Class Codes: A61F 2002/30507 : using a threaded locking member, e.g. a locking screw or a set screw
• CPC Class Codes: A61F 2002/30515 : using a locking wedge or block
• CPC Class Codes: A61F 2002/3052 : unrestrained in only one direction, e.g. moving unidirectionally
• CPC Class Codes: A61F 2002/30538 : for adjusting angular orientation
• CPC Class Codes: A61F 2002/3055 : for adjusting length
• CPC Class Codes: A61F 2002/30556 : for adjusting thickness
• CPC Class Codes: A61F 2002/30563 : having elastic means or damping means, different from springs, e.g. including an elastomeric core or shock absorbers
• CPC Class Codes: A61F 2002/30565 : having spring elements
• CPC Class Codes: A61F 2002/30578 : having apertures, e.g. for receiving fixation screws
• CPC Class Codes: A61F 2002/30579 : with mechanically expandable devices, e.g. fixation devices
• CPC Class Codes: A61F 2002/30601 : telescopic
• CPC Class Codes: A61F 2002/30624 : Hinged joint, e.g. with transverse axle restricting the movement
• CPC Class Codes: A61F 2002/30649 : Ball-and-socket joints
• CPC Class Codes: A61F 2002/30662 : with rotation-limiting means
• CPC Class Codes: A61F 2002/30772 : Apertures or holes, e.g. of circular cross section
• CPC Class Codes: A61F 2002/30785 : parallel
• CPC Class Codes: A61F 2002/3079 : Stepped or enlarged apertures, e.g. having discrete diameter changes
• CPC Class Codes: A61F 2002/30841 : Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• CPC Class Codes: A61F 2002/30904 : serrated profile, i.e. saw-toothed
• CPC Class Codes: A61F 2002/443 : having two transversal endplates and at least one intermediate component
• CPC Class Codes: A61F 2002/4622 : having the shape of a forceps or a clamp
• CPC Class Codes: A61F 2002/4627 : with linear motion along or rotating motion about the instrument axis or the implantation direction, e.g. telescopic, along a guiding rod, screwing inside the instrument
• CPC Class Codes: A61F 2002/4628 : with linear motion along or rotating motion about an axis transverse to the instrument axis or to the implantation direction, e.g. clamping
• CPC Class Codes: A61F 2002/4629 : connected to the endoprosthesis or implant via a threaded connection
• CPC Class Codes: A61F 2210/0014 : using shape memory or superelastic materials, e.g. nitinol
• 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 2220/0075 : sutured, ligatured or stitched, retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2220/0091 : connected by a hinged linkage mechanism, e.g. of the single-bar or multi-bar linkage type
• 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 2230/0069 : cylindrical
• CPC Class Codes: A61F 2250/0006 : for adjusting angular orientation
• CPC Class Codes: A61F 2250/0009 : for adjusting thickness
• CPC Class Codes: A61F 2310/00023 : Titanium or titanium-based alloys, e.g. Ti-Ni alloys

Abstract

An articulating expandable intervertebral implant is described for insertion between vertebrae of a human spine. The articulating expandable intervertebral implant includes an upper body that engages a first vertebra, a lower body that engages a second vertebra, and an insert. The inferior surface of the upper body may include a concave portion. The superior surface of the insert may include a convex portion. The insert may be positioned between the superior surface of the lower body and the concave portion of the inferior surface of the upper body. In some embodiments, an expansion member may engage the insert to increase a height of the intervertebral implant and/or allow or increase articulation of the upper body with respect to the insert. The insert may include one or more features designed to limit articulation of the upper body with respect to the insert.

Claims

1. An intervertebral implant for a human spine, comprising:

an upper body comprising an inferior surface and a superior surface, wherein the superior surface of the upper body is configured to engage a first vertebra of the human spine, and wherein the inferior surface of the upper body comprises a substantially planar surface comprising a plurality of protrusions extending therefrom;

a lower body comprising a superior surface and an inferior surface, wherein the inferior surface of the lower body is configured to engage a second vertebra of the human spine;

an insert configured to be positioned between the superior surface of the lower body and the inferior surface of the upper body, wherein the insert is configured to rotate about a rotational axis, wherein the rotational axis passes through at least a portion of the insert, wherein rotating the insert about the rotational axis causes at least a portion of the insert to engage one or more of the plurality of protrusions of the upper body to move the upper body away from the lower body in a direction substantially parallel to the rotational axis to increase a separation distance between the upper body and the lower body of the intervertebral implant to form a gap between the upper body and the lower body; and

a spacer configured to be placed in the gap after insertion of the intervertebral implant between the first vertebra and the second vertebra, wherein the spacer is configured to maintain at least a portion of the increased separation distance between the upper body and the lower body of the intervertebral implant.

2. The intervertebral implant of claim 1, wherein the upper body comprises an upper portion and lower portion, and wherein a superior surface of the lower portion comprises a convex portion, and the inferior surface of the upper portion comprises a concave portion, and wherein the convex portion of the lower portion and the concave portion of the upper portion are configured to be coupled to allow articulation of the upper portion of the upper body with respect to the lower portion of the upper body.

3. The intervertebral implant of claim 1, wherein an inferior surface of the insert is substantially flat.

4. The intervertebral implant of claim 1, wherein the insert inhibits the upper body from contacting the lower body after expansion of the intervertebral implant.

5. The intervertebral implant of claim 1, wherein the rotational axis substantially aligns with a longitudinal axis of the insert.

6. The intervertebral implant of claim 1, wherein one or more of the plurality of protrusions extending from the inferior surface of the upper body comprise one or more cam ramps.

7. The intervertebral implant of claim 1, wherein the insert comprises one or more radial protrusions extending in a radial direction with respect to the rotational axis of the insert, wherein at least one of the radial protrusions comprises a substantially planar surface that is substantially parallel to the rotational axis, and wherein the substantially planar surface of the radial protrusion is configured to be engaged by an advancement element to rotate the insert about the rotational axis.

8. An intervertebral implant for a human spine, comprising:

an upper body comprising;

an upper portion comprising a concave inferior surface and a superior surface, wherein the superior surface of the upper body is configured to engage a first vertebra of the human spine; and

a lower portion comprising an convex superior surface and an inferior surface, wherein the convex portion of the lower portion and the concave portion of the upper portion are configured to be coupled to allow articulation of the upper portion of the upper body with respect to the lower portion of the upper body, and wherein the inferior surface of the lower portion of the upper body comprises a substantially planar surface comprising a plurality of protrusions extending therefrom;

a lower body comprising a superior surface and an inferior surface, wherein the inferior surface of the lower body is configured to engage a second vertebra of the human spine; and

an insert configured to be positioned between the superior surface of the lower body and the inferior surface of the upper body, wherein the insert is configured to rotate about a rotational axis, wherein the rotational axis passes through at least a portion of the insert, wherein rotating the insert about the rotational axis causes at least a portion of the insert to engage one or more of the plurality of protrusions of the upper body to move the upper body away from the lower body in a direction substantially parallel to the rotational axis to increase a separation distance between the upper body and the lower body of the intervertebral implant to foam a gap between the upper body and the lower body after insertion of the intervertebral implant between the first vertebra and the second vertebra.

9. The intervertebral implant of claim 8, wherein the rotational axis substantially aligns with a longitudinal axis of the insert.

10. The intervertebral implant of claim 8, wherein one or more of the plurality of protrusions extending from the inferior surface of the upper body comprise one or more cam ramps.

11. The intervertebral implant of claim 8, wherein the insert comprises one or more radial protrusions extending in a radial direction with respect to the rotational axis of the insert, wherein at least one of the radial protrusions comprises a substantially planar surface that is substantially parallel to the rotational axis, and wherein the substantially planar surface of the radial protrusion is configured to be engaged by an advancement element to rotate the insert about the rotational axis.

12. The intervertebral implant of claim 8, further comprising a spacer configured to be placed in the gap after insertion of the intervertebral implant between the first vertebra and the second vertebra, wherein the spacer is configured to maintain at least a portion of the increased separation distance between the upper body and the lower body of the intervertebral implant.

13. The intervertebral implant of claim 8, wherein an inferior surface of the insert is substantially flat.

14. The intervertebral implant of claim 8, wherein the insert inhibits the upper body from contacting the lower body after expansion of the intervertebral implant.

15. An intervertebral implant for a human spine, comprising:

a first body comprising a first external surface configured to engage a first vertebra of the human spine, and comprising a first internal surface opposite the first external surface, the first internal surface comprising a substantially planar surface comprising a plurality of protrusions extending therefrom;

a second body comprising a second external surface configured to engage a second vertebra of the human spine, and comprising a second internal surface opposite the second external surface; and

an insert configured to be positioned between the first internal surface of the first body and the second internal surface of the second body, wherein the insert is configured to be rotated about a rotational axis, wherein the rotational axis passes through at least a portion of the insert, wherein rotating the insert about the rotational axis causes at least a portion of the insert to engage at least one of the plurality of protrusions extending from the first internal surface of the first body to move the first body away from the second body in a direction substantially parallel to the rotational axis to increase a separation distance between the first body and the second body of the intervertebral implant to form a gap between the first body and the second body.

16. The intervertebral implant of claim 15, further comprising a spacer configured to be disposed in the gap between the first body and the second body, wherein the spacer is configured to inhibit movement of the first internal surface and the second internal surface relative to one another to maintain at least a portion of the increased separation distance between the first body and the second body of the intervertebral implant.

17. The intervertebral implant of claim 16, wherein the spacer comprises a protrusion configured to engage a recess of the insert when the spacer is fully disposed in the gap between the first body and the second body to inhibit unintentional removal of the spacer from the intervertebral implant during use.

18. The intervertebral implant of claim 15, wherein the rotational axis substantially aligns with a longitudinal axis of the insert.

19. The intervertebral implant of claim 15, wherein one or more of the plurality of protrusions extending from the internal surface of the first body comprise one or more cam ramps.

20. The intervertebral implant of claim 15, wherein the insert comprises one or more radial protrusions extending in a radial direction with respect to the rotational axis of the insert, wherein at least one of the radial protrusions comprise a substantially planar surface that is substantially parallel to the rotational axis, and wherein the substantially planar surface of the radial protrusion is configured to be engaged by an advancement element to rotate the insert about the rotational axis.

21. The intervertebral implant of claim 15, wherein the first body comprises a first portion and a second portion, wherein a surface of the first portion comprises a convex portion, and a surface of the second portion comprises a concave portion, and wherein the convex portion and the concave portion are configured to engage one another to allow articulation of the first portion with respect to the second portion.

22. An intervertebral implant for a human spine, comprising:

a first body comprising a first external surface configured to engage a first vertebra of the human spine, and a first internal surface opposite the first external surface, the first internal surface comprising a substantially planar surface comprising one or more protrusions extending therefrom;

a second body comprising a second external surface configured to engage a second vertebra of the human spine, and comprising a second internal surface opposite the second external surface; and

an insert configured to be positioned between the first internal surface of the first body and the second internal surface of the second body,

wherein the insert is configured to be rotated about a rotational axis, wherein the rotational axis passes through at least a portion of the insert,

wherein the insert comprises one or more radial protrusions extending in a radial direction with respect to the rotational axis of the insert, wherein at least one of the radial protrusions comprise a substantially planar surface that is substantially parallel to the rotational axis, wherein the substantially planar surface of the radial protrusion is configured to be engaged by an advancement element to rotate the insert about the rotational axis, and

wherein rotating the insert about the rotational axis causes at least a portion of the insert to engage at least one of the one or more protrusions extending from the first internal surface of the first body to move the first body away from the second body in a direction substantially parallel to the rotational axis to increase a separation distance between the first body and the second body of the intervertebral implant to form a gap between the first body and the second body.