Expandable corpectomy spinal fusion cage

• US 8,241,363 B2
• Filed: 12/19/2007
• Issued: 08/14/2012
• Est. Priority Date: 12/19/2007
• Status: Active Grant

• Current Assignee: Hand Innovations LLC (Johnson & Johnson)
• Original Assignee: Depuy Spine Incorporated (Johnson & Johnson)
• Inventors: Sommerich, Robert, Presbrey, Glen Arthur, Meer, Martin, Pohl, Gerhard Franz
• Primary Examiner(s): Robert, Eduardo C
• Assistant Examiner(s): NEGRELLIRODRIGUEZ, CHRISTINA
• Application Number:
  US11/960,623
• Publication Number:
  US 20090164017A1
• Time in Patent Office: 1,700 Days
• Field of Search: 623 1711- 1716, 606246-249, 606/57
• US Class Current: 623/17.16
• CPC Class Codes: A61B 2017/0256 for the spine
• CPC Class Codes: A61F 2/44 for the spine, e.g. vertebrae, spinal discs
• 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 2002/30367 with additional means for preventing said rotation
• CPC Class Codes: A61F 2002/30507 using a threaded locking member, e.g. a locking screw or a set screw
• CPC Class Codes: A61F 2002/3055 for adjusting length
• CPC Class Codes: A61F 2002/30593 hollow
• CPC Class Codes: A61F 2002/30601 telescopic
• CPC Class Codes: A61F 2002/30784 Plurality of holes
• CPC Class Codes: A61F 2002/30841 Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• CPC Class Codes: A61F 2002/449 comprising multiple spinal implants located in different intervertebral spaces or in different vertebrae
• CPC Class Codes: A61F 2002/4622 having the shape of a forceps or a clamp
• 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 2220/0033 made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit

Abstract

An intervertebral expandable spacer having a pair of co-axial annuluses locked together by an engagement member having i) a set screw and ii) a pressure plate having an outer face contacting the set screw and an inner face having teeth adapted to mate with the ratchet notches of the second member.

Claims

1. A spacer for insertion between two vertebrae, said spacer having a variable axial height and comprising a first member and a second member guided within the first member to be slidable relative thereto in an axial direction thereof for adjusting an overall height,

wherein the second member comprises an outer wall and ratchet notches provided at its outer wall facing the first member and extending in the axial direction,

wherein the first member comprises a wall having an engagement member, which cooperates with the ratchet notches for adjusting the overall height of the spacer, and

wherein the engagement member comprises i) a set screw and ii) a pressure plate having an outer face contacting the set screw and an inner face having teeth adapted to mate with the ratchet notches of the second member,

wherein the first member comprises a distal portion having an assembly pin, and the second member comprises a distal portion having a corresponding assembly groove, and the assembly groove mates with the assembly pin in order to maintain the second member in a slidable orientation within the first member.

2. The spacer of claim 1 wherein the set screw is a sole screw of the engagement member.

3. The spacer of claim 1 wherein the set screw has a cylindrical outer surface that is threaded.

4. The spacer of claim 1 wherein the set screw is tubular defining an axis with a plurality of internal axial recesses extending along the axis.

5. The spacer of claim 1 wherein the set screw comprises a distal end and a neck and head extension extending from the distal end so as to provide engagement with a corresponding neck and head recess of the pressure plate.

6. The spacer of claim 1 wherein the inner face of the pressure plate has at least two elongated teeth thereon forming at least one notch therebetween.

7. The spacer of claim 1 wherein the first member has a graft window therein for inserting graft material therethrough.

8. The spacer of claim 1 wherein the second member has a graft window therein for inserting graft material therethrough.

9. The spacer of claim 1 wherein the first and second members each have a graft window therein for inserting graft material therethrough.

10. The spacer of claim 9 wherein an anterior portion of the member annulus has a cutout upon its inner end that forms the second graft window.

11. The spacer of claim 1 wherein the teeth of the pressure plate extend perpendicular to the axial direction of the spacer.