NESTED EXPANDABLE SLEEVE IMPLANT

• US 20110029082A1
• Filed: 03/10/2009
• Published: 02/03/2011
• Est. Priority Date: 03/14/2008
• Status: Active Grant

• Current Assignee: Depuy Synthes Products Incorporated (Johnson & Johnson)
• Original Assignee: Synthes USA LLC (Johnson & Johnson)
• Inventors: Hall, Harry Thomas
• Granted Patent: US 8,585,762 B2
• Time in Patent Office: Days
• US Class Current: 623/17.11
• CPC Class Codes: A61B 17/68 Internal fixation devices , including fasteners and spinal fixators, even if a part thereof projects from the skin bone staples A61B17/0642
• CPC Class Codes: A61B 17/8858 laterally or radially expansible inflatable A61B17/8855
• CPC Class Codes: A61F 2/44 for the spine, e.g. vertebrae, spinal discs
• CPC Class Codes: A61F 2/4405 for apophyseal or facet joints, i.e. between adjacent spinous or transverse processes devices implanted between spinous or transverse processes A61B17/7062
• 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 2/446 having a circular or elliptical cross-section substantially parallel to the axis of the spine, e.g. cylinders or frustocones
• CPC Class Codes: A61F 2002/4495 having a fabric structure, e.g. made from wires or fibres
• CPC Class Codes: Y10S 623/902 Method of implanting

Abstract

An expandable implant for treating bone preferably in a minimally invasive manner includes a preferably cylindrical core element extending along a longitudinal axis and preferably a plurality of nestable, expandable sleeves extending along a longitudinal axis for placement radially about the core element. The plurality of nestable sleeves are sequentially insertable over the core element in such a manner that a first nestable sleeve is inserted over the core element and each subsequently inserted nestable sleeve is received between the core element and the previously inserted nestable sleeve such that the insertion of each additional sleeve causes each previously inserted sleeve to outwardly expand.

Claims

1. A kit for forming an expandable implant for treating bone, the kit comprising:

a core element having a longitudinal axis; and

a plurality of sleeves for placement radially about the core element, wherein the plurality of sleeves are capable of being sequentially insertable over the core element in such a manner that a first sleeve is inserted over the core element and each subsequently inserted sleeve is received between the core element and the previously inserted sleeve such that the insertion of each additional sleeve causes each previously inserted sleeve to outwardly expand;

wherein the core element and sleeves are supplied in substantially the same lengths.

2. The kit of claim 1 wherein the core element is substantially cylindrically shaped.

3. The kit of claim 1 wherein the sleeves are hollow tubes.

4. The kit of claim 3 further comprising an expandable membrane to provide radial compression to the expandable sleeves.

5. The kit of claim 1 wherein the sleeves comprise ribs and spacers.

6. The kit of claim 1 wherein the sleeves are expandable.

7. The kit of claim 6 wherein the sleeves comprise ribs and spacers and the ribs and spacers are not located about the entire circumference of the sleeves.

8. The kit of claim 5 wherein the sleeves comprise a one piece integral unit formed of ribs and spacers with flexible struts therebetween.

9. The kit of claim 1 wherein the sleeves have an expandable condition which forms at least one flat surface or side.

10. The kit of claim 1 wherein the sleeves are provided in a cylindrical shape and are expandable to a non-cylindrical shape.

12. The kit of claim 1 wherein the sleeves and core element have at least one of a projection and recess so that the sleeves interdigitate with each other and the core element.

11. (canceled)

13. A system for treating bone comprising:

a core element having a length, a proximal end, a distal end, a longitudinal axis and an instrument engagement feature at the proximal end;

an insertion instrument that includes a cannulated barrel and a rod element located within the cannulated barrel, the rod element further including a core element engagement feature at the distal end; and

a plurality of expandable and nestable sleeve elements, wherein the plurality of sleeve elements are configured and adapted to be being placed in end-to-end fashion along the rod element and within the cannulated barrel,

wherein the instrument engagement feature of the proximal end of the core element is engageable to the core element engagement feature of the distal end of the rod element; and

wherein the expandable sleeve elements from within the cannulated barrel are advanceable along the rod element and over the core element;

whereby advancing at least one additional expandable sleeve element from within the cannulated barrel along the rod element and between the core element and the previously inserted expandable sleeve element, causes the radial expansion of the previously inserted sleeve element, wherein the radius of the implant expands as each additional sleeve element is applied about the core element.

14. The system of claim 13 wherein the sleeve elements are preloaded in end to end fashion along the rod element and within the cannulated barrel.

15. The system of claim 14 wherein sleeve elements have an expandable condition and an unexpanded condition wherein in the unexpanded condition the sleeve elements are substantially cylindrically shaped and in the expanded condition the sleeves are non-cylindrically shaped.

16. The system of claim 15 wherein the sleeves elements comprise ribs and spacers.

17. The system of claim 16 wherein the sleeve elements are single piece integrated units with flexible struts connecting the ribs and spacers.

18. The system of claim 15 wherein the ribs and spacers are connected by at least one elastic membrane.

19. The system of claim 13 wherein the sleeve elements are capable of interdigitating with one another when the sleeve elements are stacked on top of each other.

20. The system of claim 19 wherein the sleeve elements comprise recesses and projections to mate with recesses and projections of other sleeve elements or the core element.

21. The system of claim 13 wherein the core element has a diameter of approximately 4 mm to approximately 8 mm and a length of approximately 1.5 cm to approximately 2.5 cm, and the sleeve elements have an inside diameter of approximately 4 mm to approximately 8 mm, a length of approximately 1.5 cm to approximately 2.5 cm and a thickness of approximately 1 mm to approximately 2 mm.

22. The system of claim 21 wherein the sleeve elements have an inside diameter slightly less than the core element, and a length less than the core element length.

23. The system of claim 13 further comprising an end cap attachable to the core element.

24. The system of claim 23 wherein the core element has an internal recess and the end cap has a projection that fits within the internal recess.

25. An expandable implant for treating bone, the implant comprising:

a core element having a longitudinal axis, and

a plurality of nested sleeves placed radially about the core element, wherein the sleeve located radially outward from its adjacent sleeve expands more than the adjacent sleeve and interlocks with the adjacent sleeve to form a stepped incrementally expandable implant,

wherein the implant is formed by sequentially inserting sleeves over the core element and under the previously placed sleeve, and the implant expands as each additional sleeve is applied about the core element and wherein the sleeves and core element have at least one of a projection and recess so that the sleeves interdigitate with each other and the core element.

26. A method of treating bone in a minimally invasive manner, the method including the steps of:

a) forming an access path to a bone;

b) providing a core element having a length, a proximal end, a distal end, a longitudinal axis and an instrument engagement feature at the proximal end;

c) providing an insertion instrument that includes a cannulated barrel and a rod element located within the cannulated barrel, the rod element further including a core engagement feature at the distal end, and a plurality of nestable and expandable sleeve elements disposed in end-to-end fashion along the rod element and within the cannulated barrel;

d) engaging the instrument engagement feature of the proximal end of the core element to the core engagement feature of the distal end of the rod element;

e) advancing a nestable expandable sleeve element from within the cannulated barrel along the rod element and over the core element;

f) advancing at least one additional nestable expandable sleeve element from within the cannulated barrel along the rod element and between the core element and the previously inserted nestable expandable sleeve element, thereby causing the radial expansion of the previously inserted sleeve element, wherein the radius of the implant expands as each additional sleeve element is applied about the core element.

27. The method of claim 26 further comprising inserting the core element into bone.

28. The method of claim 27 further comprising attaching the core element to the insertion instrument before inserting the core element into bone.

29. The method of claim 26 used to treat or prevent a long bone metaphyseal compression fracture in a minimally invasive manner.

30. The method of claim 26 used to treat vertebral bone.