Translaminar facet augmentation and flexible spinal stabilization

• US 20070055236A1
• Filed: 09/02/2005
• Published: 03/08/2007
• Est. Priority Date: 09/02/2005
• Status: Active Grant

• Current Assignee: Zimmer Spine, Inc. (Zimmer Biomet Holdings, Inc.)
• Original Assignee: Zimmer Spine, Inc. (Zimmer Biomet Holdings, Inc.)
• Inventors: Shinbrot, Adam, Hudgins, Robert, Griffith, Steven
• Granted Patent: US 7,799,057 B2
• Time in Patent Office: Days
• US Class Current: 606/278
• CPC Class Codes: A61B 17/7064 Devices acting on, attached to, or simulating the effect of, vertebral facets; Tools therefor
• CPC Class Codes: A61B 17/8685 comprising multiple separate parts
• CPC Class Codes: A61F 2/08 Muscles; Tendons; Ligaments sutures A61B17/04
• 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 2002/30462 retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2002/305 Snap connection
• CPC Class Codes: A61F 2002/30566 Helical springs
• 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 2002/30649 Ball-and-socket joints
• 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 2002/30665 Dual arrangement of two adjacent ball-and-socket joints
• CPC Class Codes: A61F 2002/4677 using a guide wire
• CPC Class Codes: A61F 2220/0025 Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/0075 sutured, ligatured or stitched, retained or tied with a rope, string, thread, wire or cable

Abstract

The present invention is an apparatus and method for stabilizing the facet joints of the spine. One aspect of the present invention is the stabilization of the facet joint by insertion of a facet implant through two opposing facet surfaces. The facet joint is not fixedly frozen by insertion of the screw, but instead the facet surfaces are flexibly and movably anchored to preserve movement because the screw or anchor includes a flexible intermediate portion which is positioned between the facet surfaces. The facet implant may be in the form of a screw or other anchor with the intermediate portion in the form of a polyaxial head, a cord, a spring, etc. The facet implant may furthermore be used in conjunction with a facet spacer that is placed between the first and second facet.

Claims

1. A facet implant for stabilizing a first and a second adjacent vertebrae, comprising:

a first implant member positionable and attachable through a facet of the first vertebra;

a second implant member positionable and attachable through a facet of the second vertebra; and

an intermediate implant element connecting the first and second implant members positionable between the first and second vertebra facets that controls the relative movement between the first and second vertebrae.

2. The apparatus of claim 1 wherein the first and second implant members comprise at least one of a screw, bolt, shaft, bar, dowel, fastener, peg, pin, pipe, rivet, rod, spike, stake, and staple.

3. The apparatus of claim 1 wherein the intermediate implant element comprises at least one of a spring, a cord, a polyaxial joint, a deformable metal, a deformable plastic, a ball and socket joint, and a U-joint.

4. The apparatus of claim 1 wherein the facet implant is insertable through and attachable to a portion of the lamina of one or both of the first and second vertebrae.

5. The apparatus of claim 1 wherein the facet implant is insertable through and attachable to the transverse process of one or both of the first and second vertebrae.

6. The apparatus of claim 1 wherein the first and second facet implant members are in the form of a cannulated screw.

7. The apparatus of claim 6, further comprising a removable introducing member that is insertable into a bore of the cannulated screw and substantially through the intermediate implant element.

8. The facet implant of claim 1, wherein the first and second facet members are made of a biocompatible material selected from the group consisting of metals, alloys and polymers.

9. A facet implant for stabilizing a first and a second adjacent vertebrae, comprising:

a first implant member positionable in a facet of the first vertebra and attachable to the first vertebra;

a second implant member positionable in a facet of the second vertebra and attachable to the second vertebra, wherein the first vertebra facet is adjacent to the second vertebra facet; and

a means for connecting and permitting relative movement between the first and second implant members positionable between the first and second vertebra facet surfaces.

10. A system for stabilizing an opposing pair of facet surfaces, comprising:

a first facet implant for insertion between the opposing pair of facet surfaces for providing spacing and support to the facet surfaces, the first facet implant including an articulating surface; and

a second facet implant for placement through a surface of each of the opposing pair of facet surfaces, the second facet implant including a distal element, a proximal element, and an intermediate portion, the second facet implant extending through the first facet implant such that the intermediate portion is positionable between the opposing pair of facet surfaces.

11. The system of claim 10 wherein the second facet implant is a cannulated screw and further comprises a hollow interior bore through a portion of the distal element, the proximal element, and the intermediate portion, the interior bore including left hand screw threads disposed on the interior sides of the same.

12. The system of claim 11 wherein the cannulated screw includes an introducer securable in the hollow bore for aid in placement of the cannulated screw and removable after placement of the cannulated screw.

13. The system of claim 10 wherein the first facet implant includes one or more fixation tabs for anchoring the first facet implant to the spine.

14. A system for stabilizing an opposing pair of facet surfaces, comprising:

a facet implant for insertion between an opposing pair of facet surfaces, the facet implant including an articulating surface and at least one fixation tab, the facet implant providing spacing and support to the opposing facet surfaces;

a cord for insertion through the opposing pair of facet surfaces and the facet implant; and

at least one bone anchor for anchoring the cord to the spine.

15. The system of claim 14 wherein the bone anchor is a pedicle screw.

16. A method of stabilizing a facet joint, comprising:

drilling a receiving hole through an opposing pair of facet surfaces; and

inserting a facet implant into the receiving hole such that it extends through the opposing surfaces, the facet implant including an intermediate element positioned between the opposing facet surfaces for controlling the relative movement of the pair of facet surfaces.

17. The method of claim 16 wherein the facet implant further comprises inserting a cannulated screw.

18. The method of claim 17, further comprising:

inserting a second facet implant between the opposing facet surfaces, the second facet implant including an articulating surface and one or more fixation tabs, the articulating surface providing spacing and support to the opposing facet surfaces, the fixation tabs for securing the second facet implant to the spine; and

securing the second facet implant.

19. A method for stabilizing a facet joint, comprising:

securing together two opposing facet surfaces of a facet joint with a screw, the screw including a distal element, a proximal element, and an intermediate portion, the intermediate portion positionable and attachable between the two opposing facet surfaces and providing improved structural stability to the facet joint but to also allow for movement of the facet surfaces in relation to one another.

20. A system for stabilizing the spine, comprising:

a first facet implant for insertion between an opposing pair of facet surfaces, the first facet implant being substantially T-shaped and including an articulating surface and at least one fixation wing, the articulating surface providing spacing and support to the opposing pair of facet surfaces, the fixation wings anchoring the first facet implant to the spine; and

a second implant for insertion through the opposing pair of facet surfaces and the first facet implant, the second facet implant including a screw with a distal end, a proximal end, and an intermediate portion, the intermediate portion flexibly linking the distal and proximal ends.

21. An apparatus for stabilizing a first and a second adjacent vertebra, comprising:

a screw including a proximal element, a distal element, and an intermediate portion, the proximal element and the distal element including external screw threads and connected by the intermediate portion such that the proximal element and the distal element may move relative to each other, the screw placed through a lamina of a spine, through a pair of opposing facet surfaces of a facet joint, and into the transverse process, the intermediate portion positioned between the opposing pair of facet surfaces of the facet joint.