Disc nucleus removal devices and methods
Disclosed herein are devices and methods for removing tissue. In one aspect, a device for removing tissue includes a hollow elongate member having an outer wall and a lumen, a selectively deployable tissue-cutting element extending from the hollow elongate member, and an actuation member extending through the lumen and coupled to the hollow elongate member at a location that is distal to the tissue-cutting element. Movement of the actuation member can cause the tissue-cutting element to move from the insertion configuration where the tissue-cutting element is not deployed to a tissue-cutting configuration where the tissue-cutting element is deployed such that it is radially extended relative to the insertion configuration.
1. A tissue removal device, comprising:
a hollow elongate member having an outer wall and a lumen;
a selectively deployable tissue-cutting element formed on the hollow elongate member; and
an actuation member extending through the lumen and communicating with a distal-most end of the hollow elongate member at a location that is distal to the tissue-cutting element, the actuation member configured to selectively bend the distal-most end of the hollow elongate member in multiple directions relative to a longitudinal axis of the tissue removal device,
wherein movement of the actuation member causes the tissue-cutting element to move from the insertion configuration where the tissue-cutting element is not deployed to a tissue-cutting configuration where the tissue-cutting element is deployed such that it is radially extended relative to the insertion configuration.
2. The device of claim 1 , wherein at least two adjacent slits are formed in the outer wall of the elongate member.
3. The device of claim 2 , wherein the slits are formed proximal to a distal end of the elongate member and extend proximally over a distance that is less than a length of the elongate member.
4. The device of claim 3 , wherein the tissue-cutting elements are separated by a distance in the range of about 0.1 mm to 3 mm and extend a distance in the range of about 5 to 50 mm along the elongate member.
5. The device of claim 1 , wherein the tissue-cutting element is formed on at least a portion of the hollow elongate member.
6. The device of claim 2 , wherein the tissue-cutting element is formed by the portion of the elongate member between adjacent slits that is able to extend radially when subjected to a force.
7. The device of claim 6 , wherein an edge of the tissue-cutting element includes a sharpened edge.
8. The device of claim 6 , wherein the tissue-cutting element is substantially helical.
9. The device of claim 6 , wherein the tissue-cutting element comprises at least two radially-extendable arms that are formed between a plurality of slits.
10. The device of claim 1 , wherein the actuation member effects deployment of the tissue-cutting element by compression of the elongate member.
11. The device of claim 10 , wherein the compression is effected by rotation of a portion of the elongate member distal to the tissue-cutting element.
12. The device of claim 1 , wherein the lumen of the elongate member can accommodate an irrigation fluid and suction.
13. The device of claim 12 , further comprising a fluid input conduit and a suction conduit that are disposed in the lumen.
14. The device of claim 1 , wherein the outer wall of the elongate member is adapted to be positioned within a cannula.
15. The device of claim 14 , wherein a distal end of the cannula includes a shoulder and a distal portion of the elongate member that includes the tissue-cutting element protrudes from the cannula such that a ledge formed on the elongate member abuts the shoulder of the cannula.
16. The device of claim 1 , wherein the actuation member and the elongate member are adapted to move independently of one another.
17. The device of claim 1 , wherein the tissue-cutting elements are adapted to move independently of the elongate member.
18. The device of claim 1 , further comprising a locking mechanism that is adapted to hold the actuation member in the actuated position.
19. The device of claim 1 , further comprising a steering element that is adapted to control directional movement of the elongate member.
20. The device of claim 19 , wherein the steering element is a joint formed between proximal and distal ends of the elongate member.
21. The device of claim 19 , wherein the steering element is a tether that extends through the lumen of the elongate member and is coupled to the elongate member at a location that is distal to the tissue-cutting element.
22. The device of claim 1 , wherein the elongate member is formed from a material selected from the group consisting of stainless steel, titanium, titanium alloys, cobalt chromium alloys, nitinol, nylon, polyolefins, ABS, PEEK, polysulfones, polyacetal, and combinations thereof.