Self-distracting cage

• US 8,273,124 B2
• Filed: 05/17/2007
• Issued: 09/25/2012
• Est. Priority Date: 05/17/2007
• Status: Active Grant

• Current Assignee: Depuy Synthes Products Incorporated (Johnson & Johnson)
• Original Assignee: Depuy Spine Incorporated (Johnson & Johnson)
• Inventors: Renganath, Naren, Connolly, Steven, Fisher, Michael Alan, Presbrey, Glen
• Primary Examiner(s): Robert, Eduardo C
• Assistant Examiner(s): Cumberledge, Jerry
• Application Number:
  US11/750,113
• Publication Number:
  US 20080288073A1
• Time in Patent Office: 1,958 Days
• Field of Search: 623 1711- 1716
• US Class Current: 623/17.12
• CPC Class Codes: A61F 2/30742 Bellows or hose-like seals; Sealing membranes A61B17/8808 takes precedence; sealing membranes for retaining bone substitute A61F2/2846
• CPC Class Codes: A61F 2/441 made of inflatable pockets or chambers filled with fluid, e.g. with hydrogel
• 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 2/4465 having a circular or kidney shaped cross-section substantially perpendicular to the axis of the spine
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2/484 Fluid means, i.e. hydraulic or pneumatic
• CPC Class Codes: A61F 2002/30433 using additional screws, bolts, dowels, rivets or washers e.g. connecting screws
• CPC Class Codes: A61F 2002/30538 for adjusting angular orientation
• CPC Class Codes: A61F 2002/3055 for adjusting length
• CPC Class Codes: A61F 2002/30583 filled with hardenable fluid, e.g. curable in-situ
• CPC Class Codes: A61F 2002/30586 having two or more inflatable pockets or chambers
• CPC Class Codes: A61F 2002/30601 telescopic
• CPC Class Codes: A61F 2002/443 having two transversal endplates and at least one intermediate component
• CPC Class Codes: A61F 2002/4693 hydraulic
• CPC Class Codes: A61F 2210/0085 hardenable in situ, e.g. epoxy resins
• CPC Class Codes: A61F 2220/0041 using additional screws, bolts, dowels or rivets, e.g. connecting screws
• CPC Class Codes: A61F 2250/0006 for adjusting angular orientation

Abstract

Various spinal implants and methods for stabilizing the spine are provided. In one exemplary embodiment, a spinal implant is provided having an expandable container with an interior volume that is selectively expandable between a compressed condition and an expanded condition. The expandable container is coupled to a superior endplate member having a bone-contacting surface and an engagement surface effective to mate with a superior surface of the expandable container, and an inferior endplate member having a bone-contacting surface and an engagement surface effective to mate with an inferior surface of the expandable container. In addition, at least one inlet port is formed in the expandable container and is effective to communicate a fluid to at least one cavity disposed within the interior volume of the expandable container.

Claims

1. A self-distracting spinal cage, comprising:

a superior endplate having a bone-contacting surface;

an inferior endplate having a bone-contacting surface;

a piston member disposed between the superior and inferior endplates and having a fixed member and a first movable member with a substantially fluid tight seal therebetween;

a pleated member disposed within an interior portion of the piston member; and

an inlet port configured to deliver fluid to the chamber from an external fluid source;

wherein the first movable member is coupled to the superior endplate such that as fluid is delivered to the pleated member from the external fluid source, the first movable member is configured to slide relative to the fixed member in a direction substantially perpendicular to a horizontal plane.

2. The cage of claim 1, wherein the fixed member is coupled to the inferior endplate.

3. The cage of claim 2, further comprising a first articulating joint disposed between the superior endplate and the first movable member such that the superior endplate is configured to rotate relative to the fixed member to conform to intervertebral space.

4. The cage of claim 1, wherein the piston member further includes a second movable member coupled to the inferior endplate.

5. The cage of claim 4, further comprising a second articulating joint disposed between the inferior endplate and the second movable member such that the inferior endplate is configured to rotate relative to the fixed member to conform to intervertebral space.

6. A self-distracting spinal cage, comprising:

substantially hard-walled expandable container having an interior volume configured to move between a compressed condition and an expanded condition;

a monolithic superior endplate having a substantially planar bone-contacting surface and an engagement surface effective to mate with a superior surface of the expandable container;

a monolithic inferior endplate having a substantially planar bone-contacting surface and an engagement surface effective to mate with an inferior surface of the expandable container; and

at least one inlet port formed in the expandable container that is effective to communicate a fluid to at least one cavity disposed within the interior volume of the expandable container;

wherein the superior endplate, the inferior endplate, and the expandable container have an opening that extends in a longitudinal direction therethrough.

7. The device of claim 6, wherein the implant is filled with bioactive material configured to facilitate bony ingrowth between the implant and adjacent vertebrae.

8. The device of claim 6, wherein the engagement surface of the superior endplate is fixedly mated with the superior surface of the expandable container, and the engagement surface of the inferior endplate is fixedly mated with the inferior surface of the expandable container.