Expandable spinal implant apparatus and method of use

• US 10,413,419 B2
• Filed: 02/10/2017
• Issued: 09/17/2019
• Est. Priority Date: 05/06/2009
• Status: Active Grant

• Current Assignee: Stryker European Operations Holdings, LLC (Stryker Corporation)
• Original Assignee: Stryker European Holdings I, LLC (Stryker Corporation)
• Inventors: Thibodeau, Lee L.
• Primary Examiner(s): Hammond, Ellen C
• Application Number:
  US15/429,346
• Publication Number:
  US 20170151066A1
• Time in Patent Office: 949 Days
• CPC Class Codes: A61F 2/30771 applied in original prostheses, e.g. holes or grooves
• CPC Class Codes: A61F 2/44 for the spine, e.g. vertebrae, spinal discs
• 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 2/4465 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 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 2002/30133 kidney-shaped or bean-shaped
• CPC Class Codes: A61F 2002/30281 wedge-shaped
• CPC Class Codes: A61F 2002/30354 Cylindrically-shaped protrusion and recess, e.g. cylinder of circular basis
• CPC Class Codes: A61F 2002/30367 with additional means for preventing said rotation
• CPC Class Codes: A61F 2002/3037 Translation along the common longitudinal axis, e.g. piston
• CPC Class Codes: A61F 2002/30372 with additional means for limiting said translation
• CPC Class Codes: A61F 2002/30387 Dovetail connection
• CPC Class Codes: A61F 2002/30507 using a threaded locking member, e.g. a locking screw or a set screw
• CPC Class Codes: A61F 2002/30518 with possibility of relative movement between the prosthetic parts
• CPC Class Codes: A61F 2002/3052 unrestrained in only one direction, e.g. moving unidirectionally
• CPC Class Codes: A61F 2002/30535 Special structural features of bone or joint prostheses not otherwise provided for
• 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 2002/30593 : hollow
• CPC Class Codes: A61F 2002/30604 : modular
• CPC Class Codes: A61F 2002/30774 : internally-threaded
• CPC Class Codes: A61F 2002/30782 : inclined obliquely
• 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 2230/0015 : Kidney-shaped, e.g. bean-shaped
• CPC Class Codes: A61F 2230/0086 : Pyramidal, tetrahedral, or wedge-shaped
• CPC Class Codes: A61F 2250/0009 : for adjusting thickness

Abstract

A spinal implant apparatus that is an expandable spacer including features to minimize or eliminate spacer cant or offset during and after completing the expansion process. The spacer includes a top component, a base component in engagement with the top component, and an expansion mechanism arranged to change the top component'"'"'s position with respect to the base component. The mechanism for causing expansion may be a screw, a cam, a wedge or other form of distracting device. In one embodiment, the expandable spacer includes a base component with a set of towers and a top component with a set of corresponding silos, where the towers and silos are configured to minimize or eliminate tilt of the top component as it extends upwardly from the base component.

Claims

1. An expandable intervertebral spacer, comprising:

a top component having a cap, a leading end, and a trailing end, the leading end of the top component having a bevel;

a base component having a leading end and a trailing end, the base component including a receiver extending along a longitudinal axis from the leading end of the base component to the trailing end of the base component, the receiver sized and shaped to receive and removably retain a portion of the top component therein, the leading end of the base component having a taper that decreases in height toward the leading end of the base component; and

a height adjuster having external threads, the height adjuster extending into the trailing end of the base component, rotation of the height adjuster adapted to drive a wedge toward the leading end of the top component to transition the spacer from an unexpanded condition in which the cap is flush with the receiver to an expanded condition in which the cap is spaced away from the receiver;

wherein in the unexpanded condition, the taper of the leading end of the top component and the taper of the leading end of the base component are substantially continuous with each other.

2. The spacer of claim 1, wherein the height adjuster extends at an oblique angle relative to the longitudinal axis.

3. The spacer of claim 1, further comprising an interface in the receiver aligned with the longitudinal axis and configured to receive a tool therein.

4. The spacer of claim 1, wherein the top component includes a first port extending entirely through the top component.

5. The spacer of claim 4, wherein the base component includes a second port extending entirely through the base component.

6. The spacer of claim 5, wherein the first port aligns with the second port.

7. The spacer of claim 1, wherein the top component includes a textured exterior wall.

8. The spacer of claim 1, wherein in the unexpanded condition, a top surface of the top component is parallel to a bottom surface of the bottom component.

9. The spacer of claim 8, wherein in the expanded condition, the top surface of the top component is parallel to the bottom surface of the bottom component.