Vertebral interbody spacer

• US 20050251258A1
• Filed: 05/10/2004
• Published: 11/10/2005
• Est. Priority Date: 05/10/2004
• Status: Active Grant

• Current Assignee: Warsaw Orthopedic Incorporated (Medtronic Plc)
• Original Assignee: Warsaw Orthopedic Incorporated (Medtronic Plc)
• Inventors: Jackson, Roger P.
• Granted Patent: US 8,535,378 B2
• Time in Patent Office: Days
• US Class Current: 623/17.110
• CPC Class Codes: A61F 2/28 Bones joints A61F2/30
• 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 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2002/30112 Rounded shapes, e.g. with rounded corners
• CPC Class Codes: A61F 2002/30169 Pi-shaped
• CPC Class Codes: A61F 2002/30237 partial tubes
• CPC Class Codes: A61F 2002/3028 polyhedral different from parallelepipedal and pyramidal
• 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 2002/448 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 2002/4627 with linear motion along or rotating motion about the instrument axis or the implantation direction, e.g. telescopic, along a guiding rod, screwing inside the instrument
• CPC Class Codes: A61F 2002/4628 with linear motion along or rotating motion about an axis transverse to the instrument axis or to the implantation direction, e.g. clamping
• CPC Class Codes: A61F 2220/0025 Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2230/0004 Rounded shapes, e.g. with rounded corners
• CPC Class Codes: A61F 2230/0047 Pi-shaped
• CPC Class Codes: A61F 2230/0063 Three-dimensional shapes
• CPC Class Codes: A61F 2230/0069 cylindrical
• CPC Class Codes: A61F 2310/00017 Iron- or Fe-based alloys, e.g. stainless steel
• CPC Class Codes: A61F 2310/00341 Coral, e.g. aragonite, porite
• CPC Class Codes: A61F 2310/00359 Bone or bony tissue

Abstract

A spinal fusion interbody spacer device has a solid central core positioned between laterally opening opposed concave side surfaces. The device includes spaced apart superior and inferior abutment surfaces which are convexly arced. The spacer device is implanted between a pair of adjacent vertebrae by insertion in a tipped-over orientation and then reoriented to an upright orientation for engagement of the abutment surfaces by facing surfaces of the vertebrae.

Claims

1. An interbody spacer adapted for placement between a pair of spaced and facing vertebrae of a spine;

said spacer comprising;

a) a body having upper and lower surfaces adapted to engage respective vertebrae during use and a front surface and a rear surface;

b) said body having a pair of opposed concave lateral side surfaces that extend from a front to a rear thereof; and

c) said body having a solid core located between said side surfaces.

2. The interbody spacer according to claim 1 wherein:

a) at least one of said upper and lower surfaces is curved from front to rear.

3. The interbody spacer according to claim 1 wherein:

a) both of said upper and lower surfaces are convex when viewed from a side of said spacer.

4. The interbody spacer according to claim 3 wherein:

a) said upper and lower convex surfaces are constructed of an assemblage of flat facets.

5. The interbody spacer according to claim 1 wherein:

a) said lateral sides have a generally constant radius therealong about an axis that is parallel to a front to rear central axis of said body.

6. The interbody spacer according to claim 5 wherein:

a) each of said lateral sides has an innermost region; and

b) said solid core is located between vertical planes tangentially engaging the innermost region of respective lateral side surfaces;

said core being further positioned between said upper and lower surfaces and between said front and rear surfaces.

7. The interbody spacer according to claim 1 wherein:

a) said solid core is free of pass through apertures.

8. The interbody spacer according to claim 1 wherein:

a) said side surfaces open laterally outward in opposite directions and each side surface is partially cylindrical in shape about an axis that is parallel to a central front to rear axis of said body.

9. The interbody spacer according to claim 1 wherein:

a) said body has a central front to rear axis; and

b) said core at any cross section thereof that is perpendicular to said body axis is free of pass through voids.

10. The interbody spacer according to claim 1 wherein:

a) said side surfaces in conjunction with the intersection thereof with said upper and lower surfaces form upper and lower arches on each side of said spacer; and

b) said arches cooperate with said central core to provide a strong stable support structure.

11. The interbody spacer according to claim 1 in combination with a kit for positioning the spacer between a pair of facing vertebrae further including:

a) two pair of bone screws, each pair being adapted to be screwed into respective vertebra;

b) a pair of rods;

each of said rods being receivable in two of said spaced bone screws; and

c) a closure for each bone screw to operable secure said rods to said bone screws.

12. In an interbody spacer having opposed concave side surfaces, the improvement comprising:

a) a solid central core located between said side surfaces.

13. The spacer according to claim 12 wherein:

a) said side surfaces open laterally outward and have a generally uniform radius therealong;

said side surfaces extending from near an upper surface to near a lower surface of said spacer; and

said side surfaces having an axis that is generally paralleled to a central front to rear axis of said core.

14. A method of promoting fusion between a pair of spaced and facing vertebrae comprising the steps of:

a) providing an interbody spacer having a body with a solid central core located between a pair of opposed and concave lateral side surfaces that extend from a front to a rear of the body;

b) placing said spacer in a sideways position between said vertebrae;

c) rotating said spacer to an upright position; and

d) thereafter supporting one of said vertebrae relative to the other with said spacer so as to encourage fusion of bone between said vertebrae.