Flexible tissue rasp

• US 20070123888A1
• Filed: 05/04/2006
• Published: 05/31/2007
• Est. Priority Date: 10/15/2004
• Status: Active Grant

• Current Assignee: Baxano, Inc. (Baxano Surgical, Inc.)
• Original Assignee: Baxano, Inc. (Baxano Surgical, Inc.)
• Inventors: Hlavka, Edwin, Bleich, Jeffery
• Granted Patent: US 8,048,080 B2
• Time in Patent Office: Days
• US Class Current: 606/79
• CPC Class Codes: A61B 17/00234 for minimally invasive surgery A61B17/0218, A61B17/0469, A61B17/12013, A61B17/1285, A61B17/29, A61B17/320016 take precedence
• CPC Class Codes: A61B 17/02 for holding wounds open; Tractors specula A61B1/32 ; drainage appliances for wounds A61M27/00
• CPC Class Codes: A61B 17/1659 Surgical rasps, files, planes, or scrapers
• CPC Class Codes: A61B 17/1671 for the spine
• CPC Class Codes: A61B 17/1757 for the spine
• CPC Class Codes: A61B 17/320016 Endoscopic cutting instruments, e.g. arthroscopes, resectoscopes A61B10/0233, A61B17/29, A61B17/3207 take precedence
• CPC Class Codes: A61B 17/32002 with continuously rotating, oscillating or reciprocating cutting instruments
• CPC Class Codes: A61B 17/3421 Cannulas
• CPC Class Codes: A61B 2017/00261 Discectomy
• CPC Class Codes: A61B 2017/00867 shape memory effect for prostheses A61F2210/0014
• CPC Class Codes: A61B 2017/32006 with a cutting strip, band or chain, e.g. like a chainsaw
• CPC Class Codes: A61B 2017/3488 Fixation to inner organ or inner body tissue
• CPC Class Codes: A61B 2090/08021 of the patient or his organs

Abstract

Methods and devices are described for modifying tissue in a spine of a patient to treat or alleviate spinal stenosis. In one embodiment, a method may include: advancing at least a distal portion of an elongate tissue modification device into an epidural space and between target tissue and non-target tissue in the spine; positioning the tissue modification device so that at least one abrasive surface of the device faces target tissue and at least one non-abrasive surface faces non-target tissue; applying tensioning force at or near separate distal and proximal portions of the tissue modification device; and translating the tissue modification device back and forth while maintaining at least some tensioning force to abrade at least a portion of the target tissue with the at least one abrasive surface. Unwanted damage to the non-target tissue may be prevented via the at least one non-abrasive surface.

Claims

1. A method for modifying tissue in a spine of a patient to treat or alleviate at least one of foraminal spinal stenosis and lateral recess spinal stenosis, the method comprising:

advancing at least a distal portion of an elongate, at least partially flexible, tissue modification device into an epidural space of the patient'"'"'s spine and between target tissue and non-target tissue in the spine;

positioning the tissue modification device so that at least one abrasive surface of the device faces target tissue and at least one non-abrasive surface faces non-target tissue;

applying tensioning force at or near the distal portion of the tissue modification device by pulling on distal tensioning means coupled with the tissue modification device at or near the distal portion;

applying tensioning force at or near a proximal portion of the tissue modification device by separately pulling on proximal tensioning means coupled with the tissue modification device at or near the proximal portion and not directly connected to the distal tensioning means, to urge the at least one abrasive surface against the target tissue; and

translating the tissue modification device back and forth while maintaining at least some tensioning force to abrade at least a portion of the target tissue with the at least one abrasive surface, while preventing unwanted damage to the non-target tissue with the at least one non-abrasive surface.

2. A method as in claim 1, wherein advancing the tissue modification device comprises advancing at least the distal portion through at least one channel in the patient'"'"'s spine.

3. A method as in claim 2, wherein the at least one channel comprises an intervertebral foramen.

4. A method as in claim 3, wherein advancing the tissue modification device comprises advancing at least the distal portion between two adjacent vertebrae into the epidural space and through the intervertebral foramen between the same two adjacent vertebrae.

5. A method as in claim 3, wherein advancing the tissue modification device comprises advancing at least the distal portion between two adjacent vertebrae into the epidural space and through the intervertebral foramen between two different vertebrae.

6. A method as in claim 2, wherein advancing the tissue modification device comprises advancing at least the distal portion of the device into the patient'"'"'s back at a first location and out of the patient'"'"'s back at a second location.

7. A method as in claim 1, wherein applying the tensioning force comprises:

grasping the device at or near its proximal and distal portions, using the proximal and distal tensioning means; and

manually pulling on the device toward both the proximal and distal portions.

8. A method as in claim 1, wherein applying the tensioning force comprises pulling on the distal and proximal tensioning means in substantially different directions during at least part of a tissue modification procedure.

9. A method as in claim 1, wherein abrading the target tissue comprises abrading at least one of ligament, tendon, tumor, cyst, cartilage, scar, osteophyte, inflammatory, bone and joint capsule tissue.

10. A method as in claim 1, wherein abrading the target tissue reduces impingement of the tissue on at least one of a spinal cord, a branching nerve, a dorsal root ganglion, and vascular tissue in the spine.

11. A method as in claim 1, wherein positioning the tissue modification device includes positioning at least one non-abrasive shield member to face the non-target tissue.

12. A method as in claim 11, wherein positioning the at least one shield member comprises sliding the shield member into position along the tissue modification device.

13. A method as in claim 11, wherein the at least one shield member is positioned between the target tissue and non-target tissue before advancing the tissue modification device, and wherein the tissue modification device is advanced by sliding it along the at least one shield member.

14. A method as in claim 11, wherein the shield member is disposed over a portion of the at least one abrasive surface and is advanced into the patient along with the rest of the tissue modification device.

15. A method as in claim 11, wherein at least one of a distal portion and a proximal portion of the shield member is anchored outside the patient, so as to remain substantially stationary while the tissue modification device is translated back and forth.

16. A method as in claim 1, further comprising removing debris from the patient'"'"'s spine through at least one lumen in the tissue modification device, using at least one of suction and irrigation.

17. A method as in claim 1, further comprising delivering an electrical stimulus through the tissue modification device to test positioning of the tissue modification device before abrading the tissue.

18. A method as in claim 17, further comprising observing the patient to determine if the electrical stimulus was delivered to nerve tissue.

19. A method for modifying tissue in a spine of a patient to treat or alleviate spinal stenosis, the method comprising:

advancing an elongate, at least partially flexible, shield member into an epidural space of the patient'"'"'s spine and between target tissue and non-target tissue in the spine;

exposing an abrasive surface of an elongate, at least partially flexible tissue modification member through an opening on the shield member;

applying tensioning force at or near a distal portion of at least one of the shield member and the tissue modification member by pulling on distal tensioning means coupled with the distal portion of at least one of the shield member and the tissue modification member;

applying tensioning force at or near a proximal portion of at least one of the shield member and the tissue modification member by separately pulling on proximal tensioning means coupled with the proximal portion of at least one of the shield member and the tissue modification member and not directly connected to the distal tensioning means, to urge the at least one abrasive surface against the target tissue; and

translating the tissue modification device back and forth while maintaining at least some tensioning force to abrade at least a portion of the target tissue with the abrasive surface, while preventing unwanted damage to the non-target tissue with the shield member, wherein abrading the target tissue enlarges at least one opening in the spine without completely cutting through bone.

20. A method as in claim 19, wherein advancing the shield member comprises advancing at least the distal portion through at least one channel in the patient'"'"'s spine.

21. A method as in claim 20, wherein the at least one channel comprises an intervertebral foramen.

22. A method as in claim 20, wherein advancing the shield member comprises advancing at least the distal portion of the member into the patient'"'"'s back at a first location and out of the patient'"'"'s back at a second location.

23. A method as in claim 22, further comprising anchoring the shield member outside the patient at or near at least one of the first and second locations.

24. A method as in claim 19, further comprising advancing the tissue modification member through the shield member.

25. A method as in claim 19, wherein the tissue modification member is housed within the shield member during advancement.

26. A method as in claim 19, wherein abrading the target tissue comprises abrading at least one of ligament, tendon, tumor, cyst, cartilage, scar, osteophyte, inflammatory bone and joint capsule tissue.

27. A method as in claim 19, wherein abrading the target tissue reduces impingement of the tissue on at least one of a spinal cord, a branching nerve, a dorsal root ganglion, and vascular tissue in the spine.

28. A method as in claim 19, wherein applying the tensioning force comprises:

grasping the tissue modification member at or near its proximal and distal portions, using separate proximal and distal tensioning means; and

manually pulling on the tissue modification member toward both the proximal and distal portions.

29. A method as in claim 19, wherein applying the tensioning force comprises:

grasping the shield member at or near its proximal and distal portions, using separate proximal and distal tensioning means; and

manually pulling on the shield member toward both the proximal and distal portions.

30. A method as in claim 29, further comprising anchoring the proximal and distal portions of the shield member outside the patient to maintain at least some of the tensioning force.

31. A method as in claim 19, wherein applying the tensioning force comprises pulling on the distal and proximal tensioning means in substantially different directions during at least part of a tissue modification procedure.

32. A method as in claim 19, further comprising removing debris from the patient'"'"'s spine through at least one lumen in at least one of the shield member and the tissue modification member, using at least one of suction and irrigation.

33. A method as in claim 19, further comprising delivering an electrical stimulus through at least one of the shield member and the tissue modification member to test positioning before abrading the tissue.

34. A method as in claim 33, further comprising observing the patient to determine if the electrical stimulus was delivered to nerve tissue.

35. A device for modifying tissue in a spine of a patient to treat or alleviate spinal stenosis, the device comprising:

an elongate, at least partially flexible body having a proximal portion and a distal portion;

at least one abrasive surface disposed along a portion of one side of the elongate body;

at least one non-abrasive surface located adjacent the at least one abrasive surface so as to face non-target tissue when the abrasive surface is positioned to face target tissue;

at least one proximal tensioning member coupled with the elongate body at or near the proximal portion for facilitating application of tensioning force to, and translation of, the elongate body; and

at least one distal tensioning member, coupled with the elongate body at or near the distal portion and not directly connected to the proximal tensioning member, for facilitating application of tensioning force to, and translation of, the elongate body.

36. A device as in claim 35, wherein the elongate body has a cross-sectional shape selected from the group consisting of round, ovoid, ellipsoid, flat, rectangular, square, triangular, symmetric and asymmetric.

37. A device as in claim 35, wherein the elongate body has a width of not more than 5 mm and a height of not more than 2 mm.

38. A device as in claim 35, wherein the elongate body includes at least one of a guidewire lumen, a rail, a track, and a lengthwise impression along which the device may be passed over a delivery device.

39. A device as in claim 35, wherein the at least one abrasive surface comprises a rasp.

40. A device as in claim 35, wherein each of the proximal and distal tensioning members comprises at least one of a handle, a textured gripping surface, a widened portion of the body, a shaped portion of the body, and a reeling mechanism.

41. A device as in claim 35, wherein at least one of the proximal and distal tensioning members is removably attachable to the elongate body.

42. A device as in claim 35, wherein at least one of the proximal and distal tensioning members is deployable from within the elongate body.

43. A device as in claim 35, further comprising at least one shield member coupled with the elongate body to protect the non-target tissue from damage during a tissue modification procedure.

44. A device as in claim 43, wherein the shield member is removably, slidably couplable with the elongate body.

45. A device as in claim 43, wherein the shield member comprises at least one anchor for anchoring the shield member outside the patient.

46. A device as in claim 45, wherein the shield member comprises:

a proximal anchor; and

a distal anchor.

47. A device as in claim 46, wherein the proximal and distal anchors are removably couplable with the shield member at or near proximal and distal portions thereof, respectively.

48. A device as in claim 43, wherein the shield member comprises at least one window along its length, through which the at least one abrasive surface may be exposed to modify target tissue.

49. A device as in claim 48, wherein at least one edge of the window includes a protective surface for protecting the shield member from damage by the abrasive surface.

50. A device as in claim 43, further comprising at least one electrode coupled with the shield member for testing positioning of the shield member.

51. A device as in claim 35, further comprising at least one electrode coupled with the device at or near at least one of the abrasive surface and the non-abrasive surface for testing positioning of the device.

52. A device as in claim 35, further comprising at least one lumen in the elongate body for providing at least one of suction and irrigation.

53. A device for modifying tissue in a spine of a patient to treat or alleviate spinal stenosis, the device comprising:

an elongate, at least partially flexible shield member having a proximal portion, a distal portion and at least one opening along its length;

an elongate, at least partially flexible tissue modification member disposed at least partly within the shield member, the tissue modification member having a proximal portion, a distal portion, and at least one abrasive surface;

at least one proximal tensioning member at or near the proximal portion of at least one of the shield member and the tissue modification member for facilitating application of tensioning force in a first direction; and

at least one distal tensioning member at or near the distal portion of at least one of the shield member and the tissue modification member and not directly connected to the proximal tensioning member, for facilitating application of tensioning force in a second direction.

54. A device as in claim 53, wherein the shield member comprises a hollow member, and the opening comprises a window in a sidewall of the hollow member.

55. A device as in claim 54, wherein at least one edge of the window includes a protective surface for protecting the shield member from damage by the abrasive surface.

56. A device as in claim 53, wherein the opening of the shield member extends along one side of the entire length of the shield member.

57. A device as in claim 53, wherein the shield member is removably, slibably couplable with the tissue modification member.

58. A device as in claim 53, wherein the shield member comprises at least one anchor for anchoring the shield member outside the patient.

59. A device as in claim 58, wherein the shield member comprises:

a proximal anchor; and

a distal anchor.

60. A device as in claim 59, wherein the proximal and distal anchors are removably couplable with the shield member at or near proximal and distal portions thereof, respectively.

61. A device as in claim 53, wherein the shield member includes at least one of a guidewire lumen, a rail, a track, and a lengthwise impression along which the shield member may be passed over a delivery device.

62. A device as in claim 53, wherein the tissue modification member comprises a rasp.

63. A device as in claim 53, wherein each of the proximal and distal tensioning members comprises at least one of a handle, a textured gripping surface, a widened portion of the body, a shaped portion of the body, and a reeling mechanism.

64. A device as in claim 53, wherein at least one of the proximal and distal tensioning members is removably attachable to at least one of the shield member and the tissue modification member.

65. A device as in claim 53, wherein at least one of the proximal and distal tensioning members is deployable from at least one of the shield member and the tissue modification member.

66. A device as in claim 53, further comprising at least one electrode coupled with the at least one of the shield member and the tissue modification member at or near at least one of the abrasive surface and the non-abrasive surface for testing positioning of the device.

67. A device as in claim 53, further comprising at least one lumen in at least one of the shield member and the tissue modification member for providing at least one of suction and irrigation.