Intervertebral implants and methods of use

• US 20070191953A1
• Filed: 01/27/2006
• Published: 08/16/2007
• Est. Priority Date: 01/27/2006
• Status: Active Grant

• Current Assignee: Warsaw Orthopedic Incorporated (Medtronic Plc)
• Original Assignee: SDGI Holdings Incorporated (Medtronic Plc)
• Inventors: Trieu, Hai
• Granted Patent: US 7,578,849 B2
• Time in Patent Office: Days
• US Class Current: 623/17.15
• CPC Class Codes: A61F 2/44 for the spine, e.g. vertebrae, spinal discs
• 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 2002/30014 differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2002/30113 circular
• CPC Class Codes: A61F 2002/30125 elliptical or oval
• 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 2002/30387 Dovetail connection
• CPC Class Codes: A61F 2002/30433 using additional screws, bolts, dowels, rivets or washers e.g. connecting screws
• CPC Class Codes: A61F 2002/30448 using adhesives
• CPC Class Codes: A61F 2002/30451 soldered or brazed or welded
• CPC Class Codes: A61F 2002/30528 Means for limiting said movement
• 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 2002/30571 Leaf springs
• CPC Class Codes: A61F 2002/30576 with extending fixation tabs
• CPC Class Codes: A61F 2002/30581 having a pocket filled with fluid, e.g. liquid
• CPC Class Codes: A61F 2002/30594 slotted, e.g. radial or meridian slot ending in a polar aperture, non-polar slots, horizontal or arcuate slots
• CPC Class Codes: A61F 2002/30841 Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• CPC Class Codes: A61F 2002/30878 with non-sharp protrusions, for instance contacting the bone for anchoring, e.g. keels, pegs, pins, posts, shanks, stems, struts
• CPC Class Codes: A61F 2002/3092 having an open-celled or open-pored structure
• CPC Class Codes: A61F 2002/448 : comprising multiple adjacent spinal implants within the same intervertebral space or within the same vertebra, e.g. comprising two adjacent spinal implants
• CPC Class Codes: A61F 2220/0025 : Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/0041 : using additional screws, bolts, dowels or rivets, e.g. connecting screws
• CPC Class Codes: A61F 2220/005 : using adhesives
• CPC Class Codes: A61F 2220/0058 : soldered or brazed or welded
• CPC Class Codes: A61F 2230/0006 : circular
• CPC Class Codes: A61F 2230/0008 : elliptical or oval
• 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 2250/0018 : differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2310/00011 : Metals or alloys
• CPC Class Codes: A61F 2310/00203 : containing alumina or aluminium oxide
• CPC Class Codes: A61F 2310/00239 : containing zirconia or zirconium oxide ZrO2
• CPC Class Codes: A61F 2310/00293 : containing a phosphorus-containing compound, e.g. apatite
• CPC Class Codes: A61F 2310/00796 : Coating or prosthesis-covering structure made of a phosphorus-containing compound, e.g. hydroxy(l)apatite
• CPC Class Codes: A61F 2310/0097 : Coating or prosthesis-covering structure made of pharmaceutical products, e.g. antibiotics
• CPC Class Codes: A61F 2310/00976 : Coating or prosthesis-covering structure made of proteins or of polypeptides, e.g. of bone morphogenic proteins BMP or of transforming growth factors TGF

Abstract

Implants and methods for spacing and stabilizing vertebral members. The implant in one embodiment may include first and second endplates and an intermediate section that form an interior section. An elastic member may be positioned within the interior section to space apart the endplates. The elastic member may have a variety of orientations, sizes, shapes, densities, modulus of elasticity, and other material properties depending upon the desired displacement between the first and second endplates. In use according to one embodiment, the implant may assume a first shape when the vertebral members are aligned, such as when the patient is standing erect or in a prone position. This first shape may include the first and second endplates spaced a first distance apart. During movement of the vertebral members, the endplates may be forced together. The intermediate section in combination with the elastic member may be deformed during this movement and thereby exert a force to stabilize the vertebral members.

Claims

1. An intervertebral device positioned between vertebral members, the device comprising:

an elongated member having an overlapping configuration with an intermediate section that spaces apart first and second endplates; and

an elastic member positioned between the first and second endplates and proximate to the intermediate section, the elastic member sized to space apart the first and second endplates during movement of the vertebral members.

2. The device of claim 1, wherein the first endplate has a different shape than the second endplate.

3. The device of claim 2, wherein the first endplate comprises first and second spaced-apart fingers.

4. The device of claim 1, wherein the intermediate section and the first and second endplates form a substantially C-shape.

5. The device of claim 1, wherein the intermediate section has an overlapping shape.

6. The device of claim 5, wherein the intermediate section comprises first and second support members.

7. The device of claim 1, wherein the elastic member is spaced away from the intermediate section.

8. The device of claim 1, further comprising a second elastic member positioned between the first and second endplates, the second elastic member being spaced away from the elastic member.

9. The device of claim 8, wherein the second elastic member has a different stiffness than the elastic member.

10. The device of claim 8, wherein the second elastic member has a different height than the elastic member.

11. The device of claim 1, further comprising a limiting member positioned between the first and second endplates, the limiting member being constructed to limit movement of the first and second endplates beyond a predetermined amount.

12. The device of claim 1, wherein the elastic member has a length measured between a first edge and a second edge, a height of the elastic member being variable along the length.

13. An intervertebral device positioned between vertebral members, the device comprising:

an elastic member;

a first endplate positioned above the elastic member and a second endplate positioned below the elastic member; and

an intermediate member positioned at ends of the first and second endplates and connecting together the first and second endplates, the intermediate member and the elastic member being configured to maintain the first and second endplates in a spaced apart configuration.

14. The device of claim 13, wherein the first and second endplates at least partially overlap.

15. The device of claim 13, wherein the first and second endplates and the intermediate member extend around three sides of the elastic member.

16. The device of claim 13, wherein the intermediate member has an overlapping configuration.

17. The device of claim 16, wherein a first section of the intermediate member is substantially planar and a second section of the intermediate member is substantially curved.

18. The device of claim 13, wherein the first endplate is connected to the intermediate section.

19. The device of claim 18, further comprising connecting means for connecting together the first endplate and the intermediate section.

20. The device of claim 13, wherein the first and second endplates and the intermediate section are constructed from a single, elongated member.

21. An intervertebral device positioned between vertebral members, the device comprising:

a flexible body having a width and positioned in an overlapping configuration to define a three-sided cavity; and

an elastic member positioned within the cavity and sized to space apart first and second sections of the flexible body.

22. The device of claim 21, wherein the flexible body includes an intermediate section having an overlapping configuration, the intermediate section spacing apart the first and second sections.

23. The device of claim 21, further comprising a second elastic member positioned within the cavity.

24. The device of claim 21, further comprising a limiter positioned within the cavity, the limiter being constructed to prevent first and second endplates of the flexible body from moving beyond a predetermined limit.

25. The device of claim 21, wherein a height of the elastic member varies along the length of the elastic member.

26. An intervertebral device positioned between vertebral members, the device comprising:

an elastic member;

a first endplate positioned above the elastic member and a second endplate positioned below the elastic member; and

an intermediate member integral with the first and second endplates and positioned at ends of the first and second endplates, the intermediate member and the elastic member being deformable to apply a force to the first and second endplates during movement of the vertebral members.

27. The device of claim 26, wherein the elastic member extends outward beyond the first and second endplates.

28. The device of claim 26, further comprising a second elastic member positioned between the endplates, the second elastic member having a different stiffness than the elastic member.

29. The device of claim 26, wherein the elastic member has a variable height.

30. An intervertebral device positioned between vertebral members, the device comprising:

an elongated member having a folded orientation forming first and second endplates and an intermediate section;

an elastic member positioned between the first and second endplates, the elastic member having a stiffness to apply an outward force to the first and second endplates when the first and second endplates move inward beyond a predetermined amount.

31. A method of stabilizing vertebral members comprising the steps of:

inserting an implant within an intervertebral space between first and second vertebral members;

contacting a first endplate against the first vertebral member and contacting a second endplate against the second vertebral member;

positioning an intermediate section that connects the first and second endplates in a posterior direction; and

positioning an elastic member between the first and second endplates and anteriorly to the intermediate section, the intermediate section and the elastic member being constructed of an elastic material that maintains the first and second endplates in a spaced apart orientation during movement of the first and second vertebral members.

32. The method of claim 31, further comprising inserting a second implant within the intervertebral space, the implant and the second implant being positioned bilaterally within the intervertebral space.