Vertebral body replacement device and method for use to maintain a space between two vertebral bodies within a spine

• US 8,591,587 B2
• Filed: 05/18/2012
• Issued: 11/26/2013
• Est. Priority Date: 10/30/2007
• Status: Active Grant

• Current Assignee: Aesculap Implant Systems LLC (Sartorius AG)
• Original Assignee: Aesculap Implant Systems LLC (Sartorius AG)
• Inventors: Refai, Daniel, Farris, Jeffrey A., Ebersole, Jeffrey T., Trischler, Cory Alan, Kistler, Gordon Paul, Wing, Charles
• Primary Examiner(s): BOLES, SAMEH RAAFAT
• Application Number:
  US13/475,279
• Publication Number:
  US 20120265303A1
• Time in Patent Office: 557 Days
• Field of Search: 623 1711- 1716
• US Class Current: 623/17.15
• CPC Class Codes: A61F 2/30734 Modular inserts, sleeves or augments, e.g. placed on proximal part of stem for fixation purposes or wedges for bridging a bone defect
• CPC Class Codes: A61F 2/30744 End caps, e.g. for closing an endoprosthetic cavity
• CPC Class Codes: A61F 2/44 for the spine, e.g. vertebrae, spinal discs
• 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 2/4465 having a circular or kidney shaped cross-section substantially perpendicular to the axis of the spine
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2/4637 for connecting or disconnecting two parts of a prosthesis
• 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 2002/30235 tubular, e.g. sleeves
• CPC Class Codes: A61F 2002/30331 made by longitudinally pushing a protrusion into a complementarily-shaped recess, e.g. held by friction fit
• CPC Class Codes: A61F 2002/30364 Rotation about the common longitudinal axis
• CPC Class Codes: A61F 2002/30367 with additional means for preventing said rotation
• CPC Class Codes: A61F 2002/30372 with additional means for limiting said translation
• CPC Class Codes: A61F 2002/30405 made by screwing complementary threads machined on the parts themselves
• CPC Class Codes: A61F 2002/30411 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 Class Codes: A61F 2002/30433 using additional screws, bolts, dowels, rivets or washers e.g. connecting screws
• 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 2002/30492 using a locking pin
• CPC Class Codes: A61F 2002/30495 using a locking ring
• CPC Class Codes: A61F 2002/30507 using a threaded locking member, e.g. a locking screw or a set screw
• CPC Class Codes: A61F 2002/3052 : unrestrained in only one direction, e.g. moving unidirectionally
• CPC Class Codes: A61F 2002/30523 : by means of meshing gear teeth
• CPC Class Codes: A61F 2002/30525 : Worm gears
• CPC Class Codes: A61F 2002/3054 : about a connection axis or implantation axis for selecting any one of a plurality of radial orientations between two modular parts, e.g. Morse taper connections, at discrete positions, angular positions or continuous positions
• 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 2002/30593 : hollow
• 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 2002/30772 : Apertures or holes, e.g. of circular cross section
• CPC Class Codes: A61F 2002/30818 : castellated or crenellated
• CPC Class Codes: A61F 2002/30841 : Sharp anchoring protrusions for impaction into the bone, e.g. sharp pins, spikes
• CPC Class Codes: A61F 2002/30892 : parallel
• CPC Class Codes: A61F 2002/30904 : serrated profile, i.e. saw-toothed
• CPC Class Codes: A61F 2002/4622 : having the shape of a forceps or a clamp
• 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 2002/4629 : connected to the endoprosthesis or implant via a threaded connection
• CPC Class Codes: A61F 2002/4638 : Tools for performing screwing, e.g. nut or screwdrivers, or particular adaptations therefor

Abstract

A vertebral body replacement device includes a body member and a central rod member having two threaded portions and configured to be operatively associated with the body member. The device also includes a first end member and a second end member with the end members configured to threadingly engage the threaded portions of the central rod member. The body member and the two end members are further constructed to inhibit rotational movement of the two end members when the device is positioned within a space within a spine as the two end members will engage the adjacent respective vertebral bodies following rotational actuation of the central rod member causing the end members to move in an axial direction relative to the body member, thereby allowing the two end members to apply a force to the two vertebral bodies. A surgical instrument and method for using the device are also disclosed.

Claims

1. A vertebral body replacement device comprising:

a body member comprising a tool port defined in an outer wall of the body member, a first end receptacle extending in a first direction, and a second receptacle extending in a second direction opposite to the first direction;

a central rod member having a first threaded portion, a second threaded portion, and a gear wheel portion, the central rod member extending within the body member, and the gear wheel portion having a toothed surface and a support surface;

a first end member and a second end member, the first end member having a first end face comprising an aperture defined therein and configured to slidably receive the first end receptacle therein and a threaded hole which engages the first threaded portion of the central rod member, and the second end member having a first end face comprising an aperture defined therein and configured to slidably receive the second end receptacle therein and a threaded hole which engages the second threaded portion of the central rod member,

wherein the first end member bounds the first end receptacle internally and externally in a radial direction relative to a longitudinal axis of the body member, and the second end member bounds the second end receptacle internally and externally in a radial direction relative to a longitudinal axis of the body member; and

the body member, first end member and second end member inhibit rotational movement of the first and second end members relative to the body member when the vertebral body replacement device is disposed within a space within a spinal column with the first and second end members engaging respective vertebral bodies of the spinal column and the central rod member is rotationally actuated to move the first end member and the second end member in an axial direction relative to the body member allowing for the first end member and the second end member to apply a force to the two vertebral bodies to maintain a desired space therebetween.

2. The vertebral body replacement device of claim 1, wherein the tool port is positioned between a pair of pin receiving ports, the tool port is configured to receive a tool that engages the gear wheel portion and the pin receiving ports are configured to receive engagement pins therein.

3. The vertebral body replacement device of claim 2, wherein the tool port and the first and second pin receiving ports form an alignment and indexing mechanism that allows the tool to be inserted through the tool port and into proper engagement with the gear wheel portion.

4. The vertebral body replacement device of claim 3, wherein the first and second pin receiving ports control a position of the tool being inserted through the tool port when a corresponding engagement pin engages a corresponding one of the first and second pin receiving port.

5. The vertebral body replacement device of claim 2, wherein the first and second pin receiving ports each define an elongated slot.

6. The vertebral body replacement device of claim 2, wherein the tool port and first and second pin receiving ports are equidistant from the first end member and the second end member.

7. The vertebral body replacement device of claim 2, further comprising a middle chamber extending between the first and second end receptacles, wherein the tool port and the pair of pin receiving ports extend through the outer wall of the body member and into the middle chamber.

8. The vertebral body replacement device of claim 1, further comprising a support ring having a bearing surface contacting the support surface of the gear wheel portion of the central rod member when the central rod member is operatively positioned within the body member.

9. The vertebral body replacement device of claim 8, wherein the support ring is C-shaped.

10. The vertebral body replacement device of claim 1, further comprising at least one footplate member, wherein the at least one footplate member couples to at least one of the first end member and the second end member.

11. The vertebral body replacement device of claim 1, wherein the first end member and the second end member each further comprise an external wall and an internal wall, wherein each of the first end member and the second end member includes at least one travel limiting mechanism that engages the body member to limit movement of the first end member and second end member relative to the body member.

12. The vertebral body replacement device of claim 11, wherein the first end member and the second end member each include an end wall opposite their respective first end face, and wherein at least one projection is disposed on the end wall and extends in an outward direction.

13. The vertebral body replacement device of claim 11, wherein the at least one travel limiting mechanism comprises a pin configured to slidingly engage the body member.

14. The vertebral body replacement device of claim 13, wherein the first end receptacle and the second end receptacles each comprise at least one longitudinal slot configured to receive the pin therein.

15. The vertebral body replacement device of claim 14, wherein the at least one longitudinal slot includes a terminal end which limits an expansion length the first end receptacle and the second end receptacle can be moved relative to the body member.

16. The vertebral body replacement device of claim 1, the body member further comprising a projection extending in the radial direction away from the outer wall, the projection being defined by channels extending in the outer wall parallel relative to the longitudinal axis of the body member.

17. The vertebral body replacement device of claim 16, wherein the projection has a dovetail configuration and each channel has a V-shaped cross-sectional profile.

18. The vertebral body replacement device of claim 1, wherein the first end member and the second end member each include a locking mechanism which fixes a position of the first end member and the second end member relative to the body member.

19. The vertebral body replacement device of claim 18, wherein the locking mechanism includes a locking pin aperture configured to receive a locking element.