Expandable intervertebral implant

• US 9,545,314 B2
• Filed: 04/13/2015
• Issued: 01/17/2017
• Est. Priority Date: 04/05/2008
• Status: Active Grant

• Current Assignee: Depuy Synthes Products Incorporated (Johnson & Johnson)
• Original Assignee: Depuy Synthes Products Incorporated (Johnson & Johnson)
• Inventors: Cain, Christopher Marden John
• Primary Examiner(s): Ramana, Anu
• Application Number:
  US14/685,358
• Publication Number:
  US 20150216671A1
• Time in Patent Office: 645 Days
• US Class Current: 1/1
• 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 2/4425 made of articulated components
• CPC Class Codes: A61F 2/447 substantially parallelepipedal, e.g. having a rectangular or trapezoidal cross-section
• 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 2002/30405 made by screwing complementary threads machined on the parts themselves
• CPC Class Codes: A61F 2002/30462 retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2002/30471 connected by a hinged linkage mechanism, e.g. of the single-bar or multi-bar linkage type
• CPC Class Codes: A61F 2002/30495 using a locking ring
• CPC Class Codes: A61F 2002/305 Snap connection
• CPC Class Codes: A61F 2002/3052 unrestrained in only one direction, e.g. moving unidirectionally
• CPC Class Codes: A61F 2002/30537 adjustable
• CPC Class Codes: A61F 2002/30538 for adjusting angular orientation
• CPC Class Codes: A61F 2002/3055 for adjusting length
• CPC Class Codes: A61F 2002/30579 with mechanically expandable devices, e.g. fixation devices
• CPC Class Codes: A61F 2002/30601 telescopic
• CPC Class Codes: A61F 2002/30616 Sets comprising a plurality of prosthetic parts of different sizes or orientations
• CPC Class Codes: A61F 2002/30841 Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• CPC Class Codes: A61F 2002/30884 Fins or wings, e.g. longitudinal wings for preventing rotation within the bone cavity
• CPC Class Codes: A61F 2002/4415 elements of the prosthesis being arranged in a chain like manner
• CPC Class Codes: A61F 2002/443 : having two transversal endplates and at least one intermediate component
• CPC Class Codes: A61F 2002/448 : comprising multiple adjacent spinal implants within the same intervertebral space or within the same vertebra, e.g. comprising two adjacent spinal implants
• CPC Class Codes: A61F 2002/4485 : comprising three or more adjacent spinal implants
• CPC Class Codes: A61F 2002/4627 : with linear motion along or rotating motion about the instrument axis or the implantation direction, e.g. telescopic, along a guiding rod, screwing inside the instrument
• CPC Class Codes: A61F 2002/4628 : with linear motion along or rotating motion about an axis transverse to the instrument axis or to the implantation direction, e.g. clamping
• CPC Class Codes: A61F 2220/0025 : Connections or couplings between prosthetic parts, e.g. between modular parts; Connecting elements
• CPC Class Codes: A61F 2220/0075 : sutured, ligatured or stitched, retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2220/0091 : connected by a hinged linkage mechanism, e.g. of the single-bar or multi-bar linkage type
• CPC Class Codes: A61F 2250/0006 : for adjusting angular orientation
• CPC Class Codes: A61F 2310/00023 : Titanium or titanium-based alloys, e.g. Ti-Ni alloys

Abstract

An expandable intervertebral implant is provided for insertion into an intervertebral space defined by adjacent vertebrae. The expandable intervertebral implant includes a pair of outer sleeve portions and an inner core disposed between the outer sleeve portions. Movement of the inner core relative to the outer sleeve portions causes the outers sleeve portions to deflect away from each other, thereby engaging the expandable intervertebral implant with the vertebrae and adjusting the height of the intervertebral space.

Claims

1. An expandable intervertebral implant insertable into an intervertebral disc space, the expandable intervertebral implant comprising:

an outer sleeve that defines first and second terminal ends spaced from each other along a longitudinal direction, wherein the outer sleeve includes;

i) an upper sleeve portion that defines an upper vertebral engagement surface configured to abut the upper vertebra when the implant is disposed in the intervertebral disc space, and

ii) a lower sleeve portion that defines a lower vertebral engagement surface configured to abut the lower vertebra when the implant is disposed in the intervertebral disc space, wherein

     1) the upper sleeve portion includes an upper cross beam and a pair of upper legs that each project down from opposed lateral ends of the upper cross beam toward the lower sleeve portion, the upper legs spaced from each other along a lateral direction that is perpendicular to each of the longitudinal direction and the transverse direction, and

     2) the lower sleeve portion includes a lower cross beam and a pair of lower legs that each project up from opposed lateral ends of the lower cross beam toward the upper sleeve portion, the lower legs spaced from each other along the lateral direction,

wherein the outer sleeve defines a first height along a transverse direction from the upper vertebral engagement surface to the lower vertebral engagement surface when the implant is in a first position, the transverse direction perpendicular to the longitudinal direction;

an inner core configured to translate in a first direction along the longitudinal direction relative to the outer sleeve so as to cause the implant from the first terminal end to the second terminal end to move from the first position to an expanded position, whereby the outer sleeve defines a second height along the transverse direction from the upper vertebral engagement surface to the lower vertebral engagement surface along the transverse direction, wherein the second height is greater than the first height; and

a member that joins the upper sleeve portion to the lower sleeve portion both in the first position and in the expanded position,

wherein the upper legs move away from each other in their respective entireties along the lateral direction when the implant moves from the first position to the expanded position, and the lower legs move away from each other in their respective entireties along the lateral direction when the implant moves from the first position to the expanded position,

wherein

     1) the upper and lower vertebral engagement surfaces are parallel to each other both when the implant is in the first position and the expanded position, and

     2) the upper sleeve portion and the lower sleeve portion move away from each other in their respective entireties along the transverse direction when the implant moves from the first position to the second position, and

wherein the inner core includes a projection that is configured to mate with a complementary structure of the outer sleeve to fix the implant in the expanded position.

2. The expandable intervertebral implant as recited in claim 1, wherein the outer sleeve defines a first width along a lateral direction when the outer sleeve is in the first position, the outer sleeve defines a second width along the lateral direction that is greater than the first width when the implant is in the expanded position, and the lateral direction is perpendicular to the transverse direction.

3. The expandable intervertebral implant as recited in claim 1, wherein the upper sleeve portion defines first and second sides, the lower sleeve portion defines third and fourth sides, and the member extends from the first side to the third side, and further extends from the second side to the fourth side.

4. The expandable intervertebral implant as recited in claim 1, wherein the member expands as the implant moves from the first position to the second position.