Expandable inter-body device, system, and method
Expandable spinal implants, systems and methods are disclosed. An expandable spinal implant may include a proximal end plate, a superior endplate, an inferior endplate, and a moving mechanism that is operably coupled to the superior and inferior endplates. The proximal end plate may include at least one bone screw aperture configured to orient a bone screw across a bone screw relief of the superior endplate and/or inferior endplate. The moving mechanism may include a wedge, a first sliding frame, a second sliding frame, a screw guide housing a rotatable first set screw and a rotatable second set screw. A spacing between the superior and inferior endplates may be adjusted upon simultaneous rotation of the first and second set screws and an angle of inclination between the superior and inferior endplates may be adjusted upon translating either of the first set screw and second set screw.
1. An expandable spinal implant deployable between a contracted position and an expanded position, comprising:
a superior endplate, the superior endplate including:
a first outside surface and a first inside surface opposite the first outside surface, a first proximal end and a first distal end opposite the first proximal end, and a first lateral surface and a second lateral surface opposite the first lateral surface, the first and second lateral surfaces extending between the first proximal end and the first distal end;
an inferior endplate, the inferior endplate including:
a second outside surface and a second inside surface opposite the second outside surface, a second proximal end and a second distal end opposite the second proximal end, and a third lateral surface and a fourth lateral surface opposite the third lateral surface, the third and fourth lateral surfaces extending between the second proximal end and the second distal end;
a proximal end plate including at least one bone screw aperture; and
a moving mechanism operably coupled to the superior endplate and inferior endplate, the moving mechanism including:
a wedge, a first sliding frame and a second sliding frame disposed on opposite sides of the wedge, a screw guide housing a rotatable first set screw and a rotatable second set screw opposite the first set screw, the first set screw being operably coupled to the second sliding frame and the second set screw being operably coupled to the wedge,
wherein the first set screw and second set screw are configured to rotate in a first rotation direction and a second rotation direction about a rotation axis projecting in a longitudinal direction of the moving mechanism,
wherein the moving mechanism is configured to operably adjust a spacing between the superior and inferior endplates upon simultaneous rotation of the first and second set screws along the rotation axis, and
wherein the moving mechanism is configured to operably adjust an angle of inclination between the superior and inferior endplates upon translating either one of the first set screw and second set screw along the rotation axis.
2. The expandable spinal implant of claim 1 , wherein the second sliding frame is operably coupled to the first set screw and inferior endplate and movable in the longitudinal direction of the moving mechanism by rotation of the first set screw along the rotation axis.
3. The expandable spinal implant of claim 1 , wherein the second sliding frame includes a pair of first protrusions that are operably coupled to corresponding first channels of the first sliding frame, and
wherein upon movement of the second sliding frame in the longitudinal direction the first sliding frame also moves in the longitudinal direction.
4. The expandable spinal implant of claim 1 , wherein the superior endplate further includes a first plurality of inclined ramps and the inferior endplate further includes a second plurality of inclined ramps.
5. The expandable spinal implant of claim 4 , wherein the first plurality of inclined ramps further include a first plurality of grooves and the second plurality of inclined ramps includes a second plurality of grooves.
6. The expandable spinal implant of claim 5 , wherein the first sliding frame further includes first distal contact surfaces and first proximate contact surfaces configured to act against the first plurality of inclined ramps of the superior endplate.
7. The expandable spinal implant of claim 6 , wherein the first sliding frame further includes a first plurality of guide walls operably coupled to the first plurality of grooves of the superior endplate.
8. The expandable spinal implant of claim 5 , wherein the second sliding frame further includes a second plurality of guide walls operably coupled to the second plurality of grooves of the inferior endplate.
9. The expandable spinal implant of claim 8 , wherein the second sliding frame further includes a third plurality of ramps.
10. The expandable spinal implant of claim 9 , wherein the wedge further includes a plurality of engagement surfaces configured to operably engage the third plurality of ramps of the second sliding frame.
11. The expandable spinal implant of claim 10 , wherein the wedge further includes a plurality of lateral protrusions.
12. The expandable spinal implant of claim 1 , wherein the first sliding frame further includes a first plurality of channels and the wedge further includes a second plurality of protrusions operably coupled to the first plurality of channels of the first sliding frame.
13. The expandable spinal implant of claim 1 , wherein the proximal end plate includes a plurality of attachment points radially disposed around a central aperture.
14. The expandable spinal implant of claim 1 , wherein at least one of the first outside surface and second outside surface includes a bone screw relief and the at least one bone screw aperture is configured to orient a bone screw such that it extends over the bone screw relief without coming into contact with it.
15. The expandable spinal implant of claim 1 , wherein:
the proximal end plate includes a contoured block having superior channels and inferior channels,
the superior endplate includes medial proximal rails seated within the superior channels, respectively, and
the inferior endplate includes medial proximal rails seated within the inferior channels, respectively.
16. The expandable spinal implant of claim 1 , wherein:
the at least one bone screw aperture comprises a superior bone screw aperture and an inferior bone screw aperture,
the superior endplate comprises a superior bone screw relief,
the inferior endplate comprises an inferior bone screw relief,
the superior bone screw aperture is configured to orient a corresponding superior bone screw such that it extends across the superior bone screw relief without coming into contact with it, and
the inferior bone screw aperture is configured to orient a corresponding inferior bone screw such that it extends across the inferior bone screw relief without coming into contact with it.
17. The expandable spinal implant of claim 16 , wherein:
the superior bone screw aperture is configured to orient the corresponding superior bone screw such that it extends diagonally across the superior endplate at a first angle with respect to the first lateral surface,
the inferior bone screw aperture is configured to orient the corresponding inferior bone screw such that it extends diagonally across the inferior endplate at a second angle with respect to the third lateral surface, and
the first angle and second angle are different.
18. The expandable spinal implant of claim 17 , wherein:
the proximal end plate includes at least one bone screw lock, the at least one bone screw lock being rotatable between an unlocked position and a locked position, and
when the at least one bone screw lock is in the locked position, the at least one bone screw lock prevents the corresponding superior bone screw and the corresponding inferior bone screw from backing out.
19. A spinal implant system adjustable in situ between vertebral bodies of a patient, the system comprising:
the expandable spinal implant according to claim 1 ;
a first surgical tool configured to adjust the expandable spinal implant; and
a second surgical tool configured to install at least one bone screw.
20. An expandable spinal implant, comprising:
a superior endplate and an inferior endplate extending in a longitudinal direction, at least one of the superior endplate and inferior endplate having at least one bone screw relief;
a proximal end plate including at least one bone screw aperture configured to orient a bone screw such that the bone screw extends across the at least one bone screw relief, the proximal end plate being operably coupled to the superior endplate and the inferior endplate;
a wedge and a sliding frame operably coupled to the wedge, at least one of the wedge and sliding frame being operably coupled to at least one of the superior endplate and/or inferior endplate; and
a moving mechanism operably coupled to the wedge and sliding frame, the moving mechanism defining a rotation axis extending in the longitudinal direction,
wherein the moving mechanism is configured to selectively move at least one of the wedge and sliding frame forward/backward in the longitudinal direction,
wherein upon moving both the wedge and sliding frame simultaneously forward/backward the superior and inferior endplates expand/contract with respect to one another, and
wherein the wedge and sliding frame are further configured to selectively rotate, at least partially, about the rotation axis upon movement of the wedge in the longitudinal direction to thereby adjust an inclination of the superior endplate with respect to the inferior endplate in a lateral direction perpendicular to the longitudinal direction.