Spinal implant with expandable fixation

• US 10,405,988 B2
• Filed: 03/28/2018
• Issued: 09/10/2019
• Est. Priority Date: 02/22/2008
• Status: Active Grant

• Current Assignee: Howmedica Osteonics Corp. (Stryker Corporation)
• Original Assignee: Howmedica Osteonics Corp. (Stryker Corporation)
• Inventors: Grotz, R. Thomas, Pretti, Rudy A.
• Primary Examiner(s): Ku, Si Ming
• Application Number:
  US15/938,442
• Publication Number:
  US 20180333270A1
• Time in Patent Office: 531 Days
• CPC Class Codes: A61F 2/442 Intervertebral or spinal discs, e.g. resilient non-disc-shaped intervertebral inflatable pockets A61F2/441; non-disc-shaped intervertebral fusion implants A61F2/4455
• 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 2/484 Fluid means, i.e. hydraulic or pneumatic
• 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 2002/30378 Spherically-shaped protrusion and recess
• CPC Class Codes: A61F 2002/30505 spring biased
• CPC Class Codes: A61F 2002/30538 for adjusting angular orientation
• CPC Class Codes: A61F 2002/3055 for adjusting length
• CPC Class Codes: A61F 2002/30556 for adjusting thickness
• CPC Class Codes: A61F 2002/30579 with mechanically expandable devices, e.g. fixation devices
• CPC Class Codes: A61F 2002/30583 filled with hardenable fluid, e.g. curable in-situ
• CPC Class Codes: A61F 2002/30601 telescopic
• CPC Class Codes: A61F 2002/30841 Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• CPC Class Codes: A61F 2002/4666 for measuring force, pressure or mechanical tension
• CPC Class Codes: A61F 2002/4693 hydraulic
• CPC Class Codes: A61F 2210/0085 hardenable in situ, e.g. epoxy resins
• CPC Class Codes: A61F 2220/0025 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 2250/0006 for adjusting angular orientation
• CPC Class Codes: A61F 2250/0009 : for adjusting thickness
• CPC Class Codes: A61F 2310/00023 : Titanium or titanium-based alloys, e.g. Ti-Ni alloys

Abstract

A spinal implant which is configured to be deployed between adjacent vertebral bodies. The implant has at least one fixation element with a retracted configuration to facilitate deployment of the implant and an extended configuration so as to engage a surface of an adjacent vertebral body and secure the implant between two vertebral bodies. Preferably, the implant is expandable and has a minimal dimension in its unexpanded state that is smaller than the dimensions of the neuroforamen through which it must pass to be deployed within the intervertebral space. Once within the space between vertebral bodies, the implant can be expanded so as to engage the endplates of the adjacent vertebrae to effectively distract the anterior disc space, stabilize the motion segments and eliminate pathologic spine motion. Angular deformities can be corrected, and natural curvatures restored and maintained.

Claims

1. A spinal implant for placement in a space between opposed first and second vertebral bodies, the implant comprising:

a first surface for engaging the first vertebral body;

a second surface for engaging the second vertebral body; and

an extendable fixation element having a pointed distal tip, the extendable fixation element being extendable from a contracted configuration within the implant to an extended configuration in which the pointed distal tip extends beyond the second surface to engage the second vertebral body and fix the implant within the space between the first and second vertebral bodies;

wherein the implant is configured to be operable by a user to selectively drive the first surface away from the second surface, and wherein the extendable fixation element is extendable independently of the expansion of the implant.

2. The implant of claim 1, wherein the implant is adapted to be expanded by a pressurized fluid.

3. The implant of claim 1, wherein the extendable fixation element is extendable through an opening in the second surface at a plurality of angles relative to the second surface.

4. The implant of claim 1, wherein the extendable fixation element comprises a first extendable fixation element and a second extendable fixation element.

5. The implant of claim 4, wherein the first and second extendable fixation elements are extendable independently of one another.

6. The implant of claim 1, wherein the implant is expanded by extending a first extendable support member and a second extendable support member.

7. The implant of claim 6, wherein the first extendable support member comprises a first support member received with a first cylinder and slidable along a longitudinal dimension of the first cylinder, and wherein the second extendable support member comprises a second support member received within a second cylinder and slidable along a longitudinal dimension of the second cylinder.

8. The implant of claim 6, wherein the first and second extendable support members are extendable independently of one another.

9. The implant of claim 8, wherein the first surface is positioned on a first end plate adapted to engage the first vertebral body, wherein the second surface is positioned on a second end plate and a third end plate adapted to engage the second vertebral body, wherein the first extendable support member is coupled to the first end plate and the second end plate, the first extendable support member being extendable so as to move the second end plate away from the first end plate, wherein the second extendable support member is coupled to the first end plate and the third end plate, the second extendable support member being extendable so as to move the third end plate away from the first end plate, and wherein the second and third end plates are separate from one another such that the independent extension of the first and second extendable support members independently moves the respective second and third end plates.

10. The implant of claim 9, wherein the second and third end plates are adapted to independently change angles with respect to the first end plate.

11. The implant of claim 10, wherein the first extendable support member is pivotably coupled to the second end plate at a first pivot point that is fixed with respect to the second end plate, such that the second end plate is constrained to pivot about the first pivot point, and wherein the second extendable support member is pivotably coupled to the third end plate at a second pivot point that is fixed with respect to the third end plate, such that the third end plate is constrained to pivot about the second pivot point.

12. The implant of claim 6, wherein the first and second extendable support members are laterally spaced apart from one another along a dimension of the first surface of the implant.

13. The implant of claim 12, wherein a central cavity is defined between the laterally spaced apart first and second support members, the central cavity configured to receive bone graft material for infusion from the central cavity into the space between the first and second vertebral bodies.