Expandable cage

Patent metadata

Field	Value
Publication number	US-11446155-B2
Application number	US-201916512043-A
Country	US
Kind code	B2
Filing date	Jul 15, 2019
Priority date	May 8, 2017
Publication date	Sep 20, 2022
Grant date	Sep 20, 2022

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; and
a first expansion assembly and a second expansion assembly each disposed between the first and second plates with respect to the first direction, each of the first and second expansion assemblies including:
a first ramp extending from the first plate toward the second plate;
a second ramp and a third ramp each extending from the second plate toward the first plate;
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
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, and 2) the second ramp to ride along the first ramp, thereby further increasing the distance, thereby iterating the implant from the collapsed configuration to the expanded configuration,

wherein at least a portion of the expansion wedge of each of the first and second expansion assemblies is rotatable with respect to at least one of the first and second plates, and the respective actuators of the first and second expansion assemblies are operable independent of one another so as to cause one of the first and second bone-contacting surfaces to tilt relative to the other of the first and second bone-contacting surfaces.

2. The implant of claim 1 , wherein the one of the first and second bone-contacting surfaces is configured to tilt relative to the other of the first and second bone-contacting surfaces at an angle up to and including about 25 degrees.

3. The implant of claim 1 , wherein:
the expansion wedge and the first, second, and third ramps of each of the first and second expansion assemblies are configured to iterate between the collapsed configuration and the expanded configuration with respect to the first direction, and
the one of the first and second bone-contacting surfaces is configured to tilt relative to the other of the first and second bone-contacting surfaces such that one of the first and second expansion assemblies is in the expanded configuration while the other of the first and second expansion assemblies is in the collapsed configuration.

4. The implant of claim 1 , wherein each actuator is configured to apply the drive force along a respective axis, and each expansion wedge comprises:
a first member that defines the at least the portion of the expansion wedge, the first member defining the fourth ramp; and
a second member,
wherein the first member is rotatable with respect to the second member about the respective axis, thereby allowing the one of the first and second bone-contacting surfaces to tilt relative to the other of the first and second bone-contacting surfaces.

5. The implant of claim 4 , wherein the first member is configured to ride along the third ramp responsive to the drive force, and the second member is configured to ride along the first ramp responsive to the drive force.

6. The implant of claim 5 , wherein:
the first member, the second and third ramps, and the second plate are rotationally locked with respect to each other, and
the second member, the first ramp, and the first plate are rotationally locked with respect to each other.

7. The implant of claim 4 , wherein the respective axes of the actuators of the first and second expansion assemblies are oriented along the second direction.

8. The implant of claim 7 , wherein the respective axes are spaced from each other along a third direction that is substantially perpendicular to the first and second directions.

9. The implant of claim 4 , wherein each actuator is threadedly coupled to the first and second members of the respective expansion wedge, such that rotation of the actuator about the respective axis imparts the drive force, thereby causing the first and second members to threadedly translate along the actuator.

10. The implant of claim 9 , wherein the first and second members of each expansion wedge abut one another.

11. 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;
a first expansion wedge that is slidable with respect to the support wedge; and
a second expansion wedge that is slidable with respect to the first endplate; and
an actuator that is movable with respect to the axis so as to drive the first and second expansion wedges along the axial direction so as to cause the first expansion wedge to ride along the support wedge, thereby increasing a distance between the first and second endplates;

wherein the first and second expansion wedges are rotatable relative to each other about the axis, thereby allowing one of the first and second endplates to tilt relative to the other of the first and second endplates as the distance increases.

12. The implant of claim 11 , wherein:
the support wedge supports the second endplate;
the implant further comprises another support wedge that supports the first endplate; and
the second expansion wedge is configured to ride along the another support wedge to further increase the distance between the first and second endplates.

13. The implant of claim 12 , wherein:
the support wedge includes a guide feature having a geometry;
the first expansion wedge includes a guide element having a geometry that is complimentary to the geometry of the guide feature, such that the guide element is configured to ride along the guide feature; and
the guide feature and the guide element are configured to rotationally lock the first expansion wedge to the support wedge.

14. The implant of claim 13 , wherein:
the second endplate defines a guide feature having a geometry and extending along the axial direction; and
the geometry of the guide element of the first expansion wedge is complimentary with the geometry of the guide feature of the second endplate, such that the guide element of the first expansion wedge is further configured to ride along the guide feature of the second endplate.

15. The implant of claim 12 , wherein:
the another support wedge includes a guide feature having a geometry;
the second expansion wedge includes a guide element having a geometry that is complimentary to the geometry of the guide feature of the another support wedge, such that the guide element of the second expansion wedge is configured to ride along the guide feature of the another support wedge; and
the guide feature of the another support wedge and the guide element of the second expansion wedge are configured to rotationally lock the second expansion member to the another support wedge.

16. The implant of claim 15 , wherein:
the first endplate defines a guide feature having a geometry and extending along the axial direction, and
the guide element of the second expansion wedge is further configured to ride along the guide feature of the first endplate.

Assignees

• Medos Int Sarl

Inventors

• Engstrom Connor

Classifications

• A61F2002/30579

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

• A61F2002/30556

  for adjusting thickness · CPC title

• A61F2002/30538

  for adjusting angular orientation · CPC title

• A61F2002/30411

  having two threaded end parts connected by a threaded central part with opposite threads at its opposite ends, i.e. for adjusting the distance between both end parts by rotating the central part · CPC title

• A61F2/442 Primary

  Intervertebral or spinal discs, e.g. resilient (non-disc-shaped intervertebral inflatable pockets A61F2/441; non-disc-shaped intervertebral fusion implants A61F2/4455) · CPC title