Intervertebral Device Having Expandable Endplates

• US 20080243251A1
• Filed: 03/30/2007
• Published: 10/02/2008
• Est. Priority Date: 03/30/2007
• Status: Active Grant

• Current Assignee: DePuy Synthes Products LLC (Johnson & Johnson)
• Original Assignee: Depuy Spine Incorporated (Johnson & Johnson)
• Inventors: Ramsay, Christopher, Stad, Shawn
• Granted Patent: US 8,137,401 B2
• Time in Patent Office: Days
• US Class Current: 623/17.16
• 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 2/4425 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 2002/30151 rhomboidal or parallelogram-shaped
• CPC Class Codes: A61F 2002/3037 Translation along the common longitudinal axis, e.g. piston
• 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 2002/30471 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 2002/30579 with mechanically expandable devices, e.g. fixation devices
• CPC Class Codes: A61F 2002/30604 modular
• 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 2220/0091 connected by a hinged linkage mechanism, e.g. of the single-bar or multi-bar linkage type
• CPC Class Codes: A61F 2230/0017 Angular shapes

Abstract

An intervertebral implant having an endplate that can be slidably expanded following its placement in the intervertebral space.

Claims

1. An intervertebral implant device having an expandable endplate, the endplate comprising:

a) a first base portion having an outer surface adapted for bearing against a natural endplate, an inner surface, first and second side surfaces extending between the outer and inner surfaces, a first cutout opening onto the outer surface and the first side surface and forming a first recessed surface, and

b) a first plank slidingly receivable within the first cutout and adapted to translate across the first recessed surface.

2. The endplate of claim 1 wherein the base portion further comprises a second cutout opening onto the outer surface and the second side surface and forming a second recessed surface, and wherein the endplate further comprises:

c) a second plank slidingly receivable within the second cutout and adapted to translate across the second recessed surface.

3. The endplate of claim 2 wherein the first and second cutouts are joined by a third recessed surface in the inner surface of the first base portion.

4. The endplate of claim 3 wherein the first plank has a substantially T shape having a first shaft portion having a first outer end portion, a first inner end portion and a first pair of arms extending from the outer end portion.

5. The endplate of claim 4 wherein the first pair of arms are flexible.

6. The endplate of claim 5 wherein the first pair of flexible arms are receivable in the first cutout in a contracted position.

7. The endplate of claim 5 wherein the first pair of flexible arms bear against the first side surface in an expanded position.

8. The endplate of claim 4 wherein the second plank has a substantially T shape having a second shaft portion having a second outer end portion, a second inner end portion and a second pair of arms extending from the outer end portion.

9. The endplate of claim 8 wherein the second pair of arms are flexible.

10. The endplate of claim 9 wherein the second pair of flexible arms are receivable in the second cutout in a contracted position.

11. The endplate of claim 9 wherein the second pair of flexible arms bear against the first side surface in an expanded position.

12. The endplate of claim 8 wherein the first outer end portion of the first plank is received in a recess in the second inner end portion of the second plank.

13. The endplate of claim 1 further comprising:

c) a second base portion connected with the first based portion and having an inner surface opposing the inner surface of the first base portion to enclose the first plank within the first cutout.

14. The endplate of claim 13 wherein the second base portion further has an outer surface having an articulation surface thereon.

15. The endplate of claim 13 wherein the second base portion further has an outer surface having a first recess adapted for connection to a first load-bearing strut.

16. The endplate of claim 15 wherein the load-bearing strut has an angle.

17. The endplate of claim 13 wherein the inner surface of the second base portion has a cushion element attached thereto.

18. The endplate of claim 17 wherein the cushion element comprises an expandable bag.

19. An intervertebral implant device having an expandable endplate, the endplate comprising:

a) a first outer plank having an outer surface adapted for bearing against a natural endplate, and an inner surface, and a first throughhole extending between the outer surface and the inner surface thereof,

b) a second outer plank having an outer surface adapted for bearing against a natural endplate, and an inner surface, and a second throughhole extending between the outer surface and the inner surface thereof,

c) an inner plank disposed between the inner surfaces of the outer planks and having a third throughhole extending therethrough, and

d) a pivot pin extending through each of the throughholes to pivotally connect the planks.

20. The device of claim 19 wherein each plank has a midportion, and the pivot pin extends through the midportion of each plank.

21. The device of claim 19 wherein at least two planks are nested.

22. An intervertebral prosthetic device having an expandable endplate, the endplate comprising:

a) a sleeve having an outer surface adapted for bearing against a natural endplate, an inner surface, first and second side surfaces extending between the outer and inner surfaces, and a first recess extending into the sleeve from the first side surface, and

b) a first plank slidably received in the first recess of the sleeve and pivotally connected to the sleeve.

23. The endplate of claim 22 wherein the sleeve further comprises a second recess extending into the sleeve from the second side surface, the endplate further comprising:

c) a second plank slidably received in the second recess of the sleeve and pivotally connected to the sleeve.

24. The endplate of claim 23 wherein the sleeve itself has a substantially parallelogram shape comprising a first acute corner and a second opposite acute corner.

25. The endplate of claim 23 wherein the first plank is pivotally connected to the sleeve in the first acute corner of the sleeve.

26. The endplate of claim 25 wherein the second plank is pivotally connected to the sleeve in a second opposite acute corner of the sleeve.

27. An intervertebral prosthetic device having an expandable endplate, the endplate comprising:

a) a sleeve having an outer surface adapted for bearing against a natural endplate, an inner surface, first and second side surfaces extending between the outer and inner surfaces, a first recess extending into the sleeve from the first side surface, and a second recess extending into the sleeve from the first side surface,

b) a first plank slidably received in the first recess of the sleeve, and

c) a second plank slidably received in the second recess of the sleeve.