Expandable cage

Patent metadata

Field	Value
Publication number	US-12427031-B2
Application number	US-202217818021-A
Country	US
Kind code	B2
Filing date	Aug 8, 2022
Priority date	May 8, 2017
Publication date	Sep 30, 2025
Grant date	Sep 30, 2025

Abstract

An intervertebral implant that iterates between collapsed and expanded configurations includes first and second plates spaced from one another along a first direction and defining bone-contacting surfaces facing away from each other along the first direction. An expansion assembly is positioned between the plates with respect to the first direction and includes a first support wedge that supports the first plate and defines a first ramp and a second support wedge that supports the second plate and defines second and third ramps. The expansion assembly includes an expansion wedge defining a fourth ramp. The first, second, third, and fourth ramps are each inclined with respect to a second direction that is substantially perpendicular to the first direction. At least one of the first and second support wedges is slidable along the respective supported first or second plate. The implant includes an actuator configured to apply a drive force to the expansion wedge so as to cause 1) the fourth ramp to ride along the third ramp so as to increase a distance between the bone-contacting surfaces along the first direction, and 2) the second ramp to ride along the first ramp, thereby further increasing the distance, thereby iterating the implant from the collapsed to the expanded configuration.

First claim

What is claimed:

1. An intervertebral implant configured to iterate between a collapsed configuration and an expanded configuration, the implant comprising:
a first plate and a second plate spaced from one another along a first direction, the first plate defining a first bone-contacting surface, the second plate defining a second bone-contacting surface facing away from the first bone-contacting surface along the first direction;
an expansion assembly disposed between the first and second plates with respect to the first direction, the expansion assembly including:
a first support wedge supporting the first plate, the first support wedge defining a first ramp;
a second support wedge supporting the second plate, the second support wedge defining a second ramp and a third ramp; and
an expansion wedge defining a fourth ramp,
wherein each of the first, second, third, and fourth ramps is inclined with respect to a second direction that is substantially perpendicular to the first direction, and at least one of the first and second support wedges is slidable along the respective supported first or second plate; and

an actuator configured to apply a drive force to the expansion wedge so as to cause 1) the fourth ramp to ride along the third ramp so as to increase a distance between the first and second bone-contacting surfaces along the first direction, 2) the second ramp to ride along the first ramp, thereby further increasing the distance, and 3) the second ramp to disengage from the first ramp and move away from the first ramp along the first direction as the fourth ramp continues riding along the third ramp, thereby iterating the implant from the collapsed configuration to the expanded configuration.

2. The intervertebral implant of claim 1 , wherein the expansion wedge is a first expansion wedge, the expansion assembly includes a second expansion wedge defining a fifth ramp, and the second expansion wedge is configured such that the drive force causes the fifth ramp to move into engagement with the first ramp and ride along the first ramp as the fourth ramp rides along the third ramp.

3. The intervertebral implant of claim 2 , wherein the second expansion wedge has a guide element, the first plate defines a guide feature, and the first support wedge has an additional guide feature, wherein the guide element of the second expansion wedge is configured to ride along the guide feature of the first plate and subsequently disengage the guide feature of the first plate and transition to riding along the guide feature of the first support wedge as the fourth ramp rides along the third ramp.

4. The intervertebral implant of claim 3 , wherein the actuator extends along an axis, the guide features of the first plate and the first support wedge are respective guide channels, the guide element of the second expansion wedge is a guide protrusion configured to extend within and ride along the respective guide channels, and the guide protrusion and the guide channels have complementary dovetail shapes so that the second expansion wedge is rotationally affixed with respect to the first plate with respect to rotation about the axis.

5. The intervertebral implant of claim 1 , wherein the actuator extends along an axis, the expansion wedge is a first expansion wedge that is rotationally affixed to one of the first and second plates, the expansion assembly includes a second expansion wedge rotatably fixed to the other of the first and second plates, and the first and second expansion wedges are rotatable with respect to each other about the axis, thereby allowing the first and second plates to tilt relative to each other about the axis.

6. An implant, comprising:
an actuation assembly extending between first and second endplates, the actuation assembly arranged along an axis that is oriented along an axial direction, wherein the actuation assembly comprises:
a support wedge that supports one of the first and second endplates;
an expansion wedge that is slidable along the axial direction with respect to the support wedge; and
an actuator that is movable with respect to the axis so as to drive the expansion wedge along the axial direction so as to cause the expansion wedge to ride along the support wedge, thereby increasing a distance between the first and second endplates;

wherein the expansion wedge is rotatable relative to the other of the first and second endplates about the axis, thereby allowing at least one of the first and second endplates to tilt relative to the other of the first and second endplates as the distance increases.

7. The implant of claim 6 , wherein the actuator is rotatable about the axis to drive the expansion wedge along the axial direction.

8. The implant of claim 7 , wherein the expansion wedge defines internal threads that engage external threads of the actuator to drive the expansion wedge along the axial direction.

9. The implant of claim 6 , wherein the expansion wedge is a first expansion wedge, and the implant further comprises a second expansion wedge that is slidable with respect to the other of the first and second endplates, wherein the second expansion wedge is configured to slide in unison with the first expansion wedge and rotate relative to the first expansion wedge about the axis.

10. The implant of claim 6 , wherein the support wedge is (1) rotationally affixed to the one of the first and second endplates, and (2) rotatable relative to the other of the first and second endplates about the axis.

11. The implant of claim 10 , wherein the support wedge is slidable relative to the one of the first and second endplates along the axial direction.

12. The implant of claim 6 , wherein the distance is increasable at least by a factor of 2.0.

13. The implant of claim 12 , wherein the implant is configured such that, as the distance increases, the at least one of the first and second endplates is tiltable relative to the other of the first and second endplates at an angle in a range from about 0 degrees to about 45 degrees.

14. An implant, comprising:
first and second endplates positioned opposite each other;
a first support wedge extending from the first endplate toward the second endplate;
a second support wedge extending from the second endplate toward the first endplate;
an expansion wedge that is slidable toward the first and second support wedges;
an actuator extending along an axial direction oriented along an axis, wherein the actuator is movable with respect to the axis so as to drive the expansion wedge along the axial direction and to ride along at least one of the first and second support wedges, thereby increasing a distance between the first and second endplates;
wherein the expansion wedge is translatable relative to the first and second support wedges along the axial direction, and at least one of the first and second support wedges is translatable relative to the other of the first and second support wedges along the axial direction.

15. The implant of claim 14 , wherein movement of the actuator drives the at least one of the first and second support wedges to ride along the other of the first and second support wedges while the expansion wedge rides along the at least one of the first and second support wedges.

16. The implant of claim 14 , wherein the expansion wedge is rotatable relative to one of the first and second endplates about the axis, thereby allowing the one of the first and second endplates to tilt relative to the other of the first and second endplates as the distance increases.

17. The implant of claim 16 , wherein the expansi

Assignees

• Medos Int Sarl

Inventors

• Engstrom Connor

Classifications

• A61F2002/30579

  with mechanically expandable devices, e.g. fixation devices · CPC title

• A61F2002/4638

  Tools for performing screwing, e.g. nut or screwdrivers, or particular adaptations therefor · CPC title

• A61F2002/30556

  for adjusting thickness · CPC title

• A61F2002/30538

  for adjusting angular orientation · CPC title

• A61F2002/30507

  using a threaded locking member, e.g. a locking screw or a set screw · CPC title