Expandable spinal implant and method of implanting same

Patent metadata

Field	Value
Publication number	US-9713536-B2
Application number	US-201514824965-A
Country	US
Kind code	B2
Filing date	Aug 12, 2015
Priority date	Aug 12, 2015
Publication date	Jul 25, 2017
Grant date	Jul 25, 2017

Abstract

An expandable spinal implant for insertion in a disc space between two adjacent vertebrae. The expandable spinal implant is moveable from an unexpanded configuration to an expanded configuration. The expandable spinal implant includes a first plate having plastically deformable links, a second plate, two transverse members, and a screw. The screw forces apart the transverse members which causes rotational deformation of the links and separation of the plates.

First claim

What is claimed is:

1. An expandable spinal implant for insertion into a disc space between two adjacent vertebrae, the implant comprising:
a first plate having a proximal end, an opposite distal end, a bone contacting surface, a mid-longitudinal axis extending through the proximal end and the distal end, one of a first link and a first pair of links extending away from the bone contacting surface at an acute angle to a plane including the mid-longitudinal axis proximate the proximal end, and one of a second link and a second pair of links extending away from the bone contacting surface at an acute angle to the plane including the mid-longitudinal axis proximal the distal end;
a second plate having a proximal end, an opposite distal end, a bone contacting surface, a mid-longitudinal axis extending through the proximal end and the distal end, one of a third link and a third pair of links extending away from the bone contacting surface at an acute angle to a plane including the mid-longitudinal axis proximate the proximal end, and one of a fourth link and a fourth pair of links extending away from the bone contacting surface at an acute angle to the plane including the mid-longitudinal axis proximal the distal end;
a first transverse member located between the bone contacting surfaces of the first and second plates substantially transverse to the mid-longitudinal axis, the first transverse member having the one of the first and third links and the first and third pairs of links rotationally attached thereto, the first transverse member including a threaded opening extending therethrough, the threaded opening being substantially parallel to the mid-longitudinal axis;
a second transverse member located between the bone contacting surfaces of the first and second plates substantially transverse to the mid-longitudinal axis having the one of the second and fourth links and the second and fourth pairs of links rotationally attached thereto, the second transverse member including an opening extending at least partially therein, the opening being substantially parallel to the mid-longitudinal axis; and
a screw including a leading portion and an opposite trailing portion, the screw including threads that mate with the threads of at least the threaded opening of the first transverse member, the leading portion of the screw being sized to fit at least in part within the opening of the second transverse member;
wherein the screw is configured to be advanced through the opening in the first transverse member and into the opening in the second transverse member, and continued advancement forces separation of the first and second transverse members away from each other to cause plastic deformation of the one of four links and four pairs of links until the one of the first and second links and first and second pairs of links form approximately right angles with the plane including the mid-longitudinal axis of the first plate and the third and fourth pairs of links form approximately right angles with the plane including the mid-longitudinal axis of the second plate, the deformation of the one of four links and four pairs of links causing the first and second plate to separate from one another to transition from a first unexpanded configuration to a second expanded configuration.

2. The expandable spinal implant of claim 1 , further including at least one opening in the first plate and at least one opening in the second plate configured for bone growth therethrough between the two adjacent vertebrae.

3. The expandable spinal implant of claim 1 , wherein the distal ends of the first and second plates are tapered to facilitate insertion of the expandable spinal implant into the disc space.

4. The expandable spinal implant of claim 1 , wherein the proximal ends of the first and second plates are shaped to cooperatively engage an insertion tool to facilitate insertion of the expandable spinal implant into the disc space.

5. The expandable spinal implant of claim 1 , wherein the trailing portion of the screw includes an opening configured to receive an expansion tool therein to facilitate rotation of the screw.

6. The expandable spinal implant of claim 1 , wherein lengths of the one of first and second links and the first and second pairs of links are different lengths, causing the bone contacting surfaces of the first and second plates to be angled relative to one another in the expanded configuration.

7. A method of implanting an expandable spinal implant into a disc space between two adjacent vertebrae, the method comprising:
utilizing the expandable spinal implant comprising:
a first plate having a bone contacting surface and one of first and second links and first and second pairs of links extending away from the bone contacting surface of the first plate;
a second plate having a bone contacting surface and one of third and fourth links and third and fourth pairs of links extending away from the bone contacting surface of the second plate;
a first transverse member rotationally attached to the one of the first and third links and the first and third pairs of links, the first transverse member including a threaded opening extending therethrough;
a second transverse member rotationally attached to the one of the second and fourth links and the second and fourth pairs of links, the second transverse member including an opening extending at least partially therein; and
a screw threaded through the threaded opening in the first transverse member, the screw including a non-threaded leading end inserted into the opening in the second transverse member;

inserting the expandable spinal implant into the disc space between two adjacent vertebrae; and
rotating the screw, wherein rotating the screw causes the transverse members to separate, which causes rotational deformation of the one of the four links and the four pairs of links and separation of the first and second plates.

8. The method of claim 7 , further comprising inserting bone growth material between the first and second plate after the implant is inserted in the disc space.

9. The method of claim 7 , wherein the inserting the expandable spinal implant includes engaging proximal ends of the first and second plates with an inserter configured to cooperatively engage therewith.

10. The method of claim 7 , wherein the rotating the screw includes inserting an expansion tool into a recess in a trailing end of the screw.

Assignees

• Warsaw Orthopedic Inc

Inventors

• Foley Kevin T
• Lim Roy
• Morrison Matthew M

Classifications

• A61F2002/30593

  hollow · CPC title

• A61F2002/30556

  for adjusting thickness · CPC title

• A61F2002/30538

  for adjusting angular orientation · CPC title

• A61F2/4601

  for introducing bone substitute, for implanting bone graft implants or for compacting them in the bone cavity · CPC title

• A61F2/4455 Primary

  for the fusion of spinal bodies, e.g. intervertebral fusion of adjacent spinal bodies, e.g. fusion cages (intervertebral discs A61F2/442) · CPC title