Artificial spinal disk

• US 20050107881A1
• Filed: 05/03/2004
• Published: 05/19/2005
• Est. Priority Date: 05/02/2003
• Status: Active Grant

• Current Assignee: Smart Disc, Inc.
• Original Assignee: Smart Disc, Inc.
• Inventors: Nonaka, Makoto, Alleyne, Neville, Sluder, Philip James, Gerchow, James R.
• Granted Patent: US 7,407,513 B2
• Time in Patent Office: Days
• US Class Current: 623/17.150
• 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 2/446 having a circular or elliptical cross-section substantially parallel to the axis of the spine, e.g. cylinders or frustocones
• 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 2002/30133 kidney-shaped or bean-shaped
• 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 2002/30387 Dovetail connection
• CPC Class Codes: A61F 2002/30433 using additional screws, bolts, dowels, rivets or washers e.g. connecting screws
• CPC Class Codes: A61F 2002/30492 using a locking pin
• CPC Class Codes: A61F 2002/30495 using a locking ring
• CPC Class Codes: A61F 2002/305 Snap connection
• CPC Class Codes: A61F 2002/30507 using a threaded locking member, e.g. a locking screw or a set screw
• CPC Class Codes: A61F 2002/30517 using a locking plate
• CPC Class Codes: A61F 2002/30579 with mechanically expandable devices, e.g. fixation devices
• CPC Class Codes: A61F 2002/30599 stackable
• CPC Class Codes: A61F 2002/30604 modular
• CPC Class Codes: A61F 2002/30662 with rotation-limiting means
• CPC Class Codes: A61F 2002/30663 multiaxial, e.g. biaxial; multipolar, e.g. bipolar or having an intermediate shell articulating between the ball and the socket
• CPC Class Codes: A61F 2002/30685 : Means for reducing or preventing the generation of wear particulates
• CPC Class Codes: A61F 2002/30841 : Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• CPC Class Codes: A61F 2002/30884 : Fins or wings, e.g. longitudinal wings for preventing rotation within the bone cavity
• CPC Class Codes: A61F 2002/443 : having two transversal endplates and at least one intermediate component
• 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 2220/0041 : using additional screws, bolts, dowels or rivets, e.g. connecting screws
• CPC Class Codes: A61F 2230/0015 : Kidney-shaped, e.g. bean-shaped
• CPC Class Codes: A61F 2250/0063 : Nested prosthetic parts
• 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 2310/0058 : Coating made of diamond or of diamond-like carbon DLC

Abstract

An artificial spinal disk comprises a central capsule that is configured to slide laterally within the disk space with one or more of flexion, extension, and lateral bending of the spine so as to shift an instantaneous center of rotation of the artificial disk. In one embodiment, the invention comprises an artificial spinal disk comprising a first plate having an inwardly directed surface, a second plate having an inwardly directed surface facing generally toward the inwardly directed surface of the first plate, and a central capsule with outwardly directed opposed faces that slidably mate with the inwardly directed surfaces of the first and second plates.

Claims

1. An artificial spinal disk comprising:

a first plate having an inwardly directed surface;

a second plate having an inwardly directed surface facing generally toward said inwardly directed surface of said first plate; and

a central capsule with outwardly directed opposed faces that slidably mate with said inwardly directed surfaces of said first and second plates.

2. The artificial spinal disk of claim 1, wherein at least one of said inwardly directed surfaces is convexly curved toward said central capsule.

3. The artificial spinal disk of claim 1, wherein at least one of said outwardly directed surfaces of said central capsule is convexly curved toward a mating inwardly directed surface of a plate.

4. The artificial spinal disk of claim 1, wherein said central capsule comprises a pair of coupled sliding disks forming said outwardly directed opposed faces.

5. The artificial disk of claim 4, wherein said sliding disks are attached to respective first and second plates with retainer disks that slidably clamp said sliding disks between said retainer disks and said inwardly directed surfaces of said first and second plates.

6. An artificial spinal disk comprising a central capsule configured to slide laterally within the disk space with one or more of flexion, extension, and lateral bending of the spine so as to shift an instantaneous center of rotation of the artificial disk.

7. An artificial spinal disk comprising:

a first plate defining a first curved surface;

a first retainer disk affixed to said pedestal having a contour substantially matched to said first curved surface and held in spaced relation to said first curved surface;

a second plate defining a second curved surface;

a second retainer disk affixed to said second pedestal having a contour substantially matched to said second curved surface and held in spaced relation to said second curved surface;

a first sliding disk captured between said first retainer disk and said first curved surface;

a second sliding disk captured between said second retainer disk and said second curved surface, wherein said second sliding disk is coupled to said first sliding disk.

8. The artificial disk of claim 7, wherein said first and second sliding disks are coupled along their respective edges.

9. The artificial disk of claim 8, wherein said first and second sliding disks are coupled along their respective edges by a clamp.

10. An artificial spinal disk comprising a plurality of separate pieces, wherein said separate pieces are configured and sized to be placed in the disk space separate from one another, and wherein said pieces comprise couplers such that said separate pieces are attached to form a completed artificial disk only after installation within the disk space.

11. The artificial disk of claim 10, wherein said separate pieces of said artificial disk comprise at least first and second bone plates and a central capsule.

12. The artificial disk of claim 11, wherein said central capsule and said bone plates define a tongue and groove coupler.

13. The artificial disk of claim 11, wherein at least one bone plate comprises two or more coupled segments.

14. The artificial disk of claim 13, wherein said two or more coupled segments define at least one tongue and groove coupler.

15. A method of spine surgery comprising:

placing a first portion of an artificial disk into a disk space; and

separately placing one or more additional portions of said artificial disk into said disk space and mechanically coupling said additional portions to one or more portions previously placed inside said disk space so as to assemble a complete artificial disk within said disk space from artificial disk pieces that are separate outside of said disk space.

16. The method of claim 15, wherein said placing a first portion comprised attaching at least a portion of a plate to a vertebral body.

17. The method of claim 16, wherein said placing one or more additional portions comprises attaching an additional portion of said plate to said vertebral body.

18. The method of claim 16, wherein said placing one or more additional portions comprises attaching a central capsule to said plate.

19. A surgical kit for spinal surgery comprising:

a first bone plate configured for attachment to a first vertebral body;

a second bone plate configured for attachment to a second vertebral body; and

a central capsule configured to couple to said first bone plate and said second bone plate;

wherein said first bone plate, said second bone plate, and said central capsule are uncoupled from one another to allow for separate installation in a disk space during spine surgery.

20. The surgical kit of claim 19, wherein said first bone plate and said second bone plate comprise a plurality of uncoupled segments.