EXPANDABLE SYSTEMS FOR MEDICAL ELECTRICAL STIMULATION

• US 20080172117A1
• Filed: 01/12/2007
• Published: 07/17/2008
• Est. Priority Date: 01/12/2007
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Kaplan, Paula M., Skubitz, Sean P., Bolea, Stephen L., Morris, Mary M.
• Granted Patent: US 7,797,054 B2
• Time in Patent Office: Days
• US Class Current: 607/117
• CPC Class Codes: A61N 1/0553 Paddle shaped electrodes, e.g. for laminotomy
• CPC Class Codes: A61N 1/0558 Anchoring or fixation means therefor

Abstract

A medical system for electrical stimulation includes a first column of electrodes, a second column of electrodes, an expandable member disposed between first and second columns, and an expansion mechanism adapted to transmit an externally applied pressure to the expandable member. The pressure expands the expandable member in order to force the first column of electrodes apart from the second column of electrodes. The first and second columns, disposed side-by-side, may be inserted through a percutaneous needle and into a epidural space, alongside a spinal cord; after insertion, the first column may be forced apart from the second column by applying the pressure to the expandable member.

Claims

1. A medical system for electrical stimulation, the system comprising:

a first column of electrodes, and a second column of electrodes extending alongside the first column of electrodes, each of the first and second columns of electrodes including at least a first electrode separated from a second electrode by an insulative spacer;

an expandable member disposed between the first and second columns of electrodes; and

an expansion mechanism adapted to transmit externally applied pressure to expand the expandable member, the expansion of the expandable member forcing the first column of electrodes and the second column of electrodes into a position in which the first and second columns of electrodes are spaced apart from one another being approximately parallel with one another.

2. The system of claim 1, wherein:

each of the first and second columns of electrodes further includes a length defined from a proximal end of the first electrode to a distal end of the second electrode; and

the expandable member extends along the length of the first and second columns.

3. The system of claim 1, wherein the expandable member further extends alongside the first and second columns of electrodes.

4. The system of claim 1, wherein:

the expandable member comprises an inflatable chamber; and

the expansion mechanism comprises an inflation medium.

5. The system of claim 1, wherein:

the expandable member includes a first end and a second end and extends between the first end and the second end; and

the expansion mechanism comprises an elongate member adapted to bring the first end of the expandable member closer to the second end of the expandable member to expand the member.

6. The system of claim 1, further comprising a sidewall surrounding a lumen, the lumen extending proximally from the expandable member and providing a passageway for the transmission of externally applied pressure.

7. The system of claim 6, further comprising:

a body extending proximally from one of the first and second columns of electrodes; and

wherein the sidewall surrounding the lumen is a part of the body.

8. The system of claim 6, further comprising:

a body extending proximally from one of the first and second columns of electrodes; and

wherein the sidewall surrounding the lumen is separate from the body.

9. The system of claim 1, further comprising a body extending proximally from both the first and second columns of electrodes, the body including a lumen extending proximally from the expandable member and providing a passageway for the transmission of externally applied pressure.

10. The system of claim 1, further comprising:

another expandable member extending alongside at least one of the first and second columns of electrodes; and

wherein the expansion mechanism is further adapted to transmit externally applied pressure to expand the other expandable member.

11. The system of claim 1, wherein:

the first column of electrodes is coupled to a first body, the first body including a distal tip; and

the second column of electrodes is coupled to a second body, the second body including a distal tip unattached to the first body distal tip, such that, when the first and second columns of electrodes are in the spaced apart position, the first body distal tip is spaced apart from the second body distal tip.

12. A medical system for electrical stimulation, the system comprising:

a first column of electrodes, and a second column of electrodes extending alongside the first column of electrodes, each of the first and second columns of electrodes including at least a first electrode separated from a second electrode by an insulative spacer, and a length defined from a proximal end of the first electrode to a distal end of the second electrode;

an expandable member extending over the length of the first and second column of electrodes and being disposed between the first and second columns of electrodes; and

an expansion mechanism adapted to transmit externally applied pressure to expand the expandable member, the expansion of the expandable member forcing the first column of electrodes and the second column of electrodes into a position in which the first and second columns of electrodes are spaced apart from one another being approximately parallel with one another.

13. The system of claim 12, wherein:

the expandable member comprises an inflatable chamber; and

the expansion mechanism comprises an inflation medium.

14. The system of claim 12, wherein:

the expandable member includes a first end and a second end and extends between the first end and the second end; and

the expansion mechanism comprises an elongate member adapted to bring the first end of the expandable member closer to the second end of the expandable member to expand the member.

15. The system of claim 12, further comprising a sidewall surrounding a lumen, the lumen extending proximally from the expandable member and providing a passageway for the transmission of externally applied pressure.

16. The system of claim 15, further comprising:

a body extending proximally from one of the first and second columns of electrodes; and

wherein the sidewall surrounding the lumen is a part of the body.

17. The system of claim 15, further comprising:

a body extending proximally from one of the first and second columns of electrodes; and

wherein the sidewall surrounding the lumen is separate from the body.

18. The system of claim 12, further comprising a body extending proximally from both the first and second columns of electrodes, the body including a lumen extending proximally from the expandable member and providing a passageway for the transmission of externally applied pressure.

19. The system of claim 12, further comprising:

another expandable member extending alongside at least one of the first and second columns of electrodes; and

wherein the expansion mechanism is further adapted to transmit externally applied pressure to expand the other expandable member.

20. The system of claim 12, wherein:

the first column of electrodes is coupled to a first body, the first body including a distal tip; and

the second column of electrodes is coupled to a second body, the second body including a distal tip unattached to the first body distal tip, such that, when the first and second columns of electrodes are in the spaced apart position, the first body distal tip is spaced apart from the second body distal tip.

21. A medical system for electrical stimulation, the system comprising:

a first column of electrodes, and a second column of electrodes extending alongside the first column of electrodes, each of the first and second columns of electrodes including at least a first electrode separated from a second electrode by an insulative spacer;

an expandable area extending between the first and second columns of electrodes, the expandable area formed by a sidewall attached to each of the first and second columns of electrodes; and

an expansion element adapted for insertion within the expandable area in order to force the first column of electrodes apart from the second column of electrodes, when the expansion element is expanded within the area.

22. The system of claim 21, wherein the expansion element comprises an inflatable member, an inflation medium, and an inflation device coupled thereto.

23. The system of claim 21, wherein the expansion element comprises an expandable member and an elongate member adapted to bring a first end of the expandable member closer to a second end of the expandable member to expand the expansion element.

24. The system of claim 21, further comprising another sidewall surrounding a lumen, the lumen extending proximally from the expandable area and providing a passageway for the expansion element.

25. The system of claim 24, further comprising:

a body extending proximally from one of the first and second columns of electrodes; and

wherein the sidewall surrounding the lumen is a part of the body.

26. The system of claim 24, further comprising:

a body extending proximally from one of the first and second columns of electrodes; and

wherein the sidewall surrounding the lumen is separate from the body.

27. The system of claim 21, further comprising a body extending proximally from both the first and second columns of electrodes, the body including a lumen extending proximally from the expandable area and providing a passageway for the expansion element.

28. The system of claim 21, wherein:

the first column of electrodes is coupled to a first body, the first body including a distal tip; and

the second column of electrodes is coupled to a second body, the second body including a distal tip unattached to the first body distal tip, such that, when the first column of electrodes is forced apart from the second column of electrodes, the first body distal tip is also forced apart from the second body distal tip.

29. A method for implanting spinal cord stimulation electrodes, the method comprising:

inserting a first column of electrodes and a second column of electrodes through a percutaneous needle and into an epidural space alongside a spinal cord, the first and second columns being disposed side-by-side during insertion; and

applying pressure to an expandable member, the expandable member being disposed between the first and second columns of electrodes, and the applied pressure causing the expandable member to expand, thereby forcing the first column of electrodes and the second column of electrodes into a position in which the first and second columns of electrodes are spaced apart from one another and approximately parallel with one another.

30. The method of claim 29, wherein applying pressure comprises filling the expandable member with an inflation medium.

31. The method of claim 29, wherein applying pressure comprises forcing a first end of the expandable member closer to a second end of the expandable member.

32. The method of claim 29, further comprising applying another pressure to the expandable member causing the expandable member to expand further, thereby forcing the first column of electrodes and the second column of electrodes into another position in which the first and second columns of electrodes are spaced further apart from one another.

33. A medical system for electrical stimulation, the system comprising:

a first body including a distal tip;

a second body including a distal tip, the second body distal tip being unattached to the first body distal tip;

a first column of electrodes coupled to the first body in proximity to the first body distal tip, and a second column of electrodes coupled to the second body in proximity to the second body distal tip, the second column of electrodes extending alongside the first column of electrodes, and each of the first and second columns of electrodes including at least a first electrode separated from a second electrode by an insulative spacer;

an expandable member disposed between the first and second columns of electrodes; and

an expansion mechanism adapted to transmit externally applied pressure to expand the expandable member, the expansion of the expandable member forcing the first column of electrodes and the first body distal tip apart from the second column of electrodes and the second body distal tip.

34. The system of claim 33, wherein:

each of the first and second columns of electrodes further includes a length defined from a proximal end of the first electrode to a distal end of the second electrode; and

the expandable member extends along the length of the first and second columns.

35. The system of claim 33, wherein the expandable member further extends alongside the first and second columns of electrodes.

36. The system of claim 33, wherein:

the expandable member comprises an inflatable chamber; and

the expansion mechanism comprises an inflation medium.

37. The system of claim 33, wherein:

the expandable member extends between a first end thereof and a second end thereof; and

the expansion mechanism comprises an elongate member adapted to bring the first end of the expandable member closer to the second end of the expandable member to expand the member.

38. The system of claim 33, further comprising a sidewall surrounding a lumen, the lumen extending proximally from the expandable member and providing a passageway for the transmission of externally applied pressure.

39. The system of claim 33, wherein each of the first and second bodies includes a proximal end;

and further comprising another body coupled to each of the first and second body proximal ends and extending proximally therefrom.

40. The system of claim 39, wherein the other body includes a lumen extending proximally from the expandable member and providing a passageway for the transmission of externally applied pressure.

41. The system of claim 33, further comprising:

a first connector assembly and a second connector assembly; and

wherein the first body extends proximally from the first column of electrodes to the first connector assembly; and

the second body extends proximally from the second column of electrodes to the second connector assembly.

42. The system of claim 41, wherein one of the first and second bodies includes a lumen extending proximally from the expandable member and providing a passageway for the transmission of externally applied pressure.

43. The system of claim 41, further comprising a sidewall surrounding a lumen, the sidewall being separate from the first and second bodies, and the lumen extending proximally from the expandable member and providing a passageway for the transmission of externally applied pressure.

44. The system of claim 33, further comprising:

another expandable member extending alongside at least one of the first and second columns of electrodes; and

wherein the expansion mechanism is further adapted to transmit externally applied pressure to expand the other expandable member.