Expandable Devices for Emplacement in Body Parts and Methods Associated Therewith

• US 20090240335A1
• Filed: 03/24/2008
• Published: 09/24/2009
• Est. Priority Date: 03/24/2008
• Status: Active Grant

• Current Assignee: Kyphon SARL (Medtronic Plc)
• Original Assignee: Kyphon SARL (Medtronic Plc)
• Inventors: Arcenio, Gregory B., Phan, Christopher U.
• Granted Patent: US 8,795,365 B2
• Time in Patent Office: Days
• US Class Current: 623/17.160
• CPC Class Codes: A61B 17/7094 Solid vertebral fillers; devices for inserting such fillers
• CPC Class Codes: A61B 17/8869 Tensioning devices
• CPC Class Codes: A61F 2/4611 of spinal prostheses
• CPC Class Codes: A61F 2002/30224 cylindrical
• CPC Class Codes: A61F 2002/30261 parallelepipedal
• CPC Class Codes: A61F 2002/3028 polyhedral different from parallelepipedal and pyramidal
• 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 2002/30462 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 2002/30579 with mechanically expandable devices, e.g. fixation devices
• CPC Class Codes: A61F 2002/30599 stackable
• CPC Class Codes: A61F 2002/4415 elements of the prosthesis being arranged in a chain like manner
• CPC Class Codes: A61F 2220/0033 made by longitudinally pushing a protrusion into a complementary-shaped recess, e.g. held by friction fit
• 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 2230/0063 Three-dimensional shapes
• CPC Class Codes: A61F 2230/0069 cylindrical
• CPC Class Codes: A61F 2230/0082 parallelepipedal
• CPC Class Codes: A61F 2250/0063 Nested prosthetic parts

Abstract

Disclosed are devices and methods for emplacement of an expandable device in a body part of interest in human and animal subjects. In one embodiment, the expandable device comprises a cage that may be emplaced in the intervertebral disc for use in spine fusion techniques. The device is fashioned so that it may be delivered to the intervertebral disc by percutaneous means, such as via a cannula. Additionally disclosed are systems and kits employing the devices of the invention as well as methods of manufacturing the devices of the invention.

Claims

1. An expandable device for emplacing in a body part in a subject comprising:

a plurality of segments, the plurality of segments being flexibly connected in series, the expandable device having a first configuration wherein the plurality of segments are substantially unfolded, and a second configuration wherein the plurality of segments are substantially folded, and wherein a total height of the expandable device in the second configuration is substantially spanned by at least one of the plurality of segments.

2. The device of claim 1, wherein in the second configuration, the plurality of segments are folded in alternating directions.

3. The device of claim 1, wherein in the first configuration, a plurality of longitudinal axes of the plurality of segments are substantially co-axial.

4. The device of claim 1, wherein in the second configuration, plurality of longitudinal axes of the plurality of segments are substantially parallel.

5. The device of claim 1, wherein in the second configuration, a longitudinal surface of a first one of the plurality of segments is substantially flush with a longitudinal surface of a second one of the plurality of segments.

6. The device of claim 1, wherein the plurality of segments are connected by a plurality of hinges, each of the plurality of hinges having a thickness less than a thickness of each of the plurality of segments.

7. The device of claim 6, wherein the plurality of hinges biases the plurality of segments towards the second configuration.

8. The device of claim 1, wherein the plurality of segments are connected by living hinges.

9. The device of claim 1, further comprising a repositioning member connected between at least two of the plurality of segments for biasing the plurality of segments towards the second configuration.

10. The device of claim 1, further comprising a repositioning member for urging the segments between the first configuration and the second configuration.

11. The device of claim 10, wherein the repositioning member engages each of the segments, such that the repositioning member can be used by an operator of the device to urge the segments from the first configuration to the second configuration, or from the second configuration to the first configuration.

12. The device of claim 11, wherein the repositioning member comprises a wire that is passed through at least one aperture on each of the segments.

13. The device of claim 1, further comprising elements to assist in the alignment of the segments when the device is in the second configuration.

14. The device of claim 1, wherein the body part comprises a spinal disc or an intervertebral region between two vertebral bodies.

15. A method of emplacing an expandable device comprising a plurality of connected segments in a body part in a subject comprising:

(a) emplacing the expandable device in a cannula in a first configuration, wherein a plurality of longitudinal axes of the plurality of connected segments are substantially unfolded;

(b) urging the distal end of the cannula to the body part of interest;

(c) urging the expandable device through the cannula into the body part of interest; and

(d) causing the plurality of connected segments to assume a second configuration in the body part of interest wherein the plurality of connected segments are substantially folded to expand the expandable device to an expanded height, and wherein at least one of the plurality of connected segments substantially spans the expanded height.

16. The method of claim 15, wherein in the first configuration, the plurality of longitudinal axes of the plurality of connected segments are substantially co-axial.

17. The method of claim 15, wherein in the second configuration, the plurality of longitudinal axes of the plurality of connected segments are substantially parallel.

18. The method of claim 15, wherein in the second configuration, a longitudinal surface of a first one of the plurality of connected segments is substantially flush with a longitudinal surface of a second one of the plurality of connected segments.

19. The method of claim 15, wherein the plurality of connected segments are connected by a plurality of hinges, each of the plurality of hinges having a thickness less than a thickness of each of the plurality of connected segments.

20. The method of claim 15, wherein the plurality of connected segments are connected by living hinges.

21. The method of claim 15, wherein the expandable device further comprises a repositioning member for urging the segments between the first configuration and the second configuration.

22. The method of claim 15, wherein causing the plurality of connected segments to assume the second configuration comprises moving a distal one of the plurality of connected segments and a proximal one of the plurality of connected segments closer together.

23. The method of claim 15, wherein the expandable device further comprises elements to assist in the alignment of the segments when the longitudinal surfaces of at least two segments are substantially flush.

24. The method of claim 15, wherein the body part comprises a spinal disc or an intervertebral region between two vertebral bodies.

25. The method of claim 15, further comprising emplacing a bone graft material to promote fusion of a vertebral body that is adjacent to an upper surface of the deployed expandable device to a vertebral body that is adjacent to a lower surface of the deployed expandable device after the device has been emplaced.

26. The method of claim 15, wherein causing the plurality of connected segments to assume a second configuration comprises causing the plurality of connected segments to exit the cannula.

27. A kit comprising an expandable device for emplacement in a body part comprising:

(a) an expandable device comprising a plurality of segments, the plurality of segments being flexibly connected in series, the expandable device having a first configuration wherein the plurality of segments are substantially unfolded, and a second configuration wherein the plurality of segments are substantially folded, wherein a total height of the expandable device in the second configuration is substantially spanned by at least one of the plurality of segments; and

(b) a cannula for inserting the device into the body part of interest.

28. The kit of claim 27, wherein the plurality of connected segments are connected by living hinges.

29. The kit of claim 27, further comprising a repositioning member for urging the segments between the first configuration and the second configuration.

30. The kit of claim 27, wherein the segments are configured for percutaneous delivery to a body part using a cannula.

31. The kit of claim 27, further comprising a bone graft material for emplacement in an intervertebral disc space to promote fusion of a vertebral body that is adjacent to an upper surface of the deployed expandable device to a vertebral body that is adjacent to a lower surface of the deployed expandable device.

32. A method of making an expandable device for emplacement in a body part comprising:

fashioning a plurality of connected segments, the plurality of connected segments being flexibly connected in series, the expandable device having a first configuration wherein the plurality of segments are substantially unfolded, and a second configuration wherein the plurality of segments are substantially folded, wherein a total height of the expandable device in the second configuration is substantially spanned by at least one of the plurality of segments.

33. The method of claim 32, wherein each of the segments are connected to each other by a living hinge between adjacent segments.

34. A method of emplacing an expandable fusion cage comprising a plurality of connected segments in an intervertebral region between two vertebral bodies in a subject comprising:

(a) emplacing the expandable fusion cage in a cannula in a first configuration wherein a plurality of longitudinal axes of the plurality of connected segments are substantially coplanar;

(b) urging the distal end of the cannula to the intervertebral region;

(c) urging the plurality of connected segments through the cannula into the intervertebral region;

(d) moving a proximal one of the plurality of connected segments and a distal one of the plurality of connected segments closer together over a repositioning member threaded through the plurality of connected segments to place the plurality of connected segments in a second configuration by pulling the repositioning member such that the at least two segments that have emerged from the cannula become deployed such that a longitudinal surface of one segment is substantially flush with a longitudinal surface of an adjacent segment;

(e) repeating steps (c) and (d) until the expandable fusion cage has completely exited the cannula and has been fully deployed in the intervertebral region;

(f) optionally, adding a bone graft material; and

(g) removing the cannula from the intervertebral disc space.