Spinal plug for a minimally invasive facet joint fusion system

• US 20060111782A1
• Filed: 09/22/2005
• Published: 05/25/2006
• Est. Priority Date: 11/22/2004
• Status: Active Grant

• Current Assignee: minSURG International Incorporated
• Original Assignee: Orthopedic Development Corporation
• Inventors: Petersen, David A.
• Granted Patent: US 7,708,761 B2
• Time in Patent Office: Days
• US Class Current: 623/17.110
• CPC Class Codes: A61B 17/1604 Chisels; Rongeurs; Punches; Stamps
• CPC Class Codes: A61B 17/1671 for the spine
• CPC Class Codes: A61B 17/7064 Devices acting on, attached to, or simulating the effect of, vertebral facets; Tools therefor
• CPC Class Codes: A61B 2090/034 abutting on parts of the device itself
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• 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 2/4455 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 2002/30785 parallel
• CPC Class Codes: A61F 2002/30881 Circumferential ribs, flanges or fins
• CPC Class Codes: A61F 2310/00359 Bone or bony tissue
• CPC Class Codes: A61L 2430/02 for reconstruction of bones; weight-bearing implants
• CPC Class Codes: A61L 27/3608 Bone, e.g. demineralised bone matrix [DBM], bone powder

Abstract

A frustum shaped body has an aperture in a top surface and a pair of first and second opposed apertures in a side surface, first and second horizontal internal channels connect both the first and second opposed apertures. A vertical channel from the top aperture connects with the first and second channels. After the body is inserted into a hole in a facet joint, compatible synthetic or biologic material is inserted into the vertical channel until the material exits from the first and second apertures in the side surface. At least one pair of flanges on a portion of an exterior side surface of the body acts as a detent to hold the body in place within the facet joint hole.

Claims

1. A facet joint fusion plug comprising:

a substantially solid frustum shaped body having an aperture in a top surface and a pair of first opposed apertures in a side surface and a pair of second opposed apertures in the side surface, both the first and second opposed apertures positioned in a lower portion of the body distal from the top surface;

a vertical channel directed downwardly from the aperture in the top surface, the vertical channel intersecting with a first horizontal channel connecting the first opposed pair of apertures and terminating at a second horizontal channel connecting the second opposed pair of apertures;

at least one pair of flanges partially surrounding a bottom portion of an exterior surface of the body; and

the body formed from a material selected from the group consisting of synthetic cortical bone, a harvested synthetic cortical and compacted iliac crest graft and a cadaveric allograft.

2. The facet joint fusion plug according to claim 1, wherein there is a third pair of opposed apertures in a side surface of the body and the vertical channel intersects with a third horizontal channel connecting the third pair of apertures.

3. The facet joint fusion plug according to claim 1, wherein a second pair of flanges partially surrounds a bottom portion of the exterior surface of the body.

4. The facet joint fusion plug according to claim 2, wherein a second pair of flanges partially surrounds a bottom portion of the exterior surface of the body.

5. The facet joint fusion plug according to claim 1, wherein the first and second horizontal channels are on parallel horizontal planes.

6. The facet joint fusion plug according to claim 2, wherein the third horizontal channel is on a parallel horizontal plane above the first and second horizontal channels.

7. The facet joint fusion plug according to claim 1, wherein the body is formed from synthetic cortical bone.

8. The facet joint fusion plug according to claim 1, wherein the body is formed from a harvested and compacted iliac crest graft.

9. The facet joint fusion plug according to claim 1, wherein the body is formed from a cadaveric allograft.

10. A plug mounted in a hole between bones forming a facet joint, the plug comprising:

a substantially solid frustum shaped body having an aperture in a top surface, the top surface having a greater diameter than a bottom surface;

a first pair of opposed apertures in a side surface of the body, the first pair of apertures connected by a first horizontal channel;

a second pair of opposed apertures in a side surface of the body, the second pair of apertures connected by a second horizontal channel in a parallel plane to the first horizontal channel;

a vertical channel directed downwardly from the aperture in the top surface, the vertical channel intersecting with the first horizontal channel and terminating in the second horizontal channel;

at least one pair of flanges partially surrounding a bottom portion of an exterior surface of the body; and

a synthetic or biologic material compatible with bone passing through the top aperture and exiting from the first and second pair of apertures in the side surface of the body.

11. The plug mounted in a hole between bones forming a facet joint according to claim 10, wherein a third pair of opposed apertures are connected by a third horizontal channel intersecting with the vertical channel, the synthetic or biologic material exiting from the third pair of apertures.

12. The plug mounted in a hole between bones forming a facet joint according to claim 10, wherein there are two pair of flanges spaced apart partially surrounding a bottom portion of an exterior surface of the body.

13. The plug mounted in a hole between bones forming a facet joint according to claim 10, wherein the body is formed from a material selected from the group consisting of a synthetic cortical bone, a harvested and compacted iliac crest graft and a cadaveric allograft.

14. The plug body according to claim 13, formed from a synthetic cortical bone.

15. The plug body according to claim 13, formed from a harvested and compacted iliac crest graft.

16. The plug body according to claim 13, formed from an iliac cadaveric allograft.

17. A method of mounting a plug in a facet joint C1-C2 and L5-S1, the method comprising:

cutting an arthroscopic type portal in the tissue of a patient outside a diseased or damaged facet joint;

creating a hole between two opposed bones forming the facet joint;

inserting a frustum preshaped plug into the hole, the plug having a shape substantially the same as the hole;

providing the plug with an aperture on a top surface, the top surface diameter being greater than a bottom surface diameter;

providing the plug with at least one pair of flanges partially surrounding an outside side wall and at least a first and second opposed pair of side apertures in the side wall of the plug;

providing an internal cortical channel from the top surface aperture to a first horizontal channel connecting the first pair of apertures and a second horizontal channel connecting the second pair of apertures;

inserting an applicator tube into the aperture in the top surface;

inserting a synthetic or biologic material compatible with bone into the applicator tube; and

providing sufficient pressure on the synthetic or biologic material to cause egress of the material from the side wall apertures.

18. The method according to claim 17, wherein the preshaped plug is provided as a synthetic cortical bone.

19. The method according to claim 17, wherein the preshaped plug is provided as a compacted iliac crest graft.

20. The method according to claim 17, wherein the preshaped plug is provided as a cadaveric allograft.

21. A solid plug mounted in a hole between bones forming a facet joint, the plug consisting of a substantially frustum shaped body having a posterior end with a diameter of 4 to 12 mm and an anterior end with a diameter less than the posterior end.