Apparatus and methods for optimizing anchoring force

• US 20050277981A1
• Filed: 06/09/2004
• Published: 12/15/2005
• Est. Priority Date: 06/09/2004
• Status: Active Grant

• Current Assignee: USGI Medical, Inc.
• Original Assignee: USGI Medical, Inc.
• Inventors: Saadat, Vahid, Ewers, Richard C., Maahs, Tracy D., Michlitsch, Kenneth J., Khairkhahan, Alex
• Granted Patent: US 8,206,417 B2
• Time in Patent Office: Days
• US Class Current: 606/213
• CPC Class Codes: A61B 17/0401 Suture anchors, buttons or pledgets, i.e. means for attaching sutures to bone, cartilage or soft tissue; Instruments for applying or removing suture anchors A61B17/0642 takes precedence; fixation devices for tendons or ligaments A61F2/0811
• CPC Class Codes: A61B 17/0469 Suturing instruments for use in minimally invasive surgery, e.g. endoscopic surgery
• CPC Class Codes: A61B 17/0482 Needle or suture guides guides for drills, pins or wire A61B17/17; for puncturing needles A61B17/3403
• CPC Class Codes: A61B 17/0644 penetrating the tissue, deformable to closed position
• CPC Class Codes: A61B 2017/00867 shape memory effect for prostheses A61F2210/0014
• CPC Class Codes: A61B 2017/0454 the anchor being crimped or clamped on the suture
• CPC Class Codes: A61B 2017/0464 for soft tissue
• CPC Class Codes: A61B 2017/0496 for tensioning sutures
• CPC Class Codes: A61B 2017/06052 Needle-suture combinations in which a suture is extending inside a hollow tubular needle, e.g. over the entire length of the needle hollow suture needles A61B2017/061
• CPC Class Codes: A61B 2090/037 with a frangible part, e.g. by reduced diameter

Abstract

Apparatus and methods for optimizing anchoring force are described herein. In securing tissue folds, over-compression of the tissue directly underlying the anchors is avoided by utilizing tissue anchors having expandable arms configured to minimize contact area between the anchor and tissue. When the anchor is in its expanded configuration, a load is applied to the anchor until it is optimally configured to accommodate a range of deflections while the anchor itself exerts a substantially constant force against the tissue. Various devices, e.g., stops, spring members, fuses, strain gauges, etc., can be used to indicate when the anchor has been deflected to a predetermined level within the optimal range. Moreover, other factors to affect the anchor characteristics include, e.g., varying the number of arms or struts of the anchor, positioning of the arms, configuration of the arms, the length of the collars, etc.

Claims

1. An anchor adapted to exert a substantially constant force against a tissue surface, comprising:

a proximal collar;

a distal collar;

a plurality of deformable arms each extending between the proximal and distal collars,

wherein the anchor is adapted to self-configure from a delivery configuration to an expanded configuration for placement against the tissue surface, and

wherein the anchor is further adapted to exert a substantially constant force against the tissue surface over a range of deflections when the proximal and distal collars are moved relative to one another.

2. The anchor of claim 1 wherein the proximal collar defines a lumen therethrough.

3. The anchor of claim 1 wherein the distal collar defines a lumen therethrough.

4. The anchor of claim 1 wherein the anchor is comprised of a shape memory or superelastic alloy.

5. The anchor of claim 1 wherein the anchor is comprised of nitinol.

6. The anchor of claim 1 wherein the plurality of deformable arms define a space between adjacent arms for contact against the tissue surface.

7. The anchor of claim 1 wherein the deformable arms are parallel.

8. The anchor of claim 1 wherein the deformable arms each define a non-uniform cross-section along a length of the arm.

9. The anchor of claim 8 wherein each of the arms is tapered along its length.

10. The anchor of claim 1 wherein each of the arms define at least a proximal section, a distal section, and a middle section.

11. The anchor of claim 10 wherein the proximal and distal sections have uniform cross-sections.

12. The anchor of claim 1 wherein the arms number at least two.

13. The anchor of claim 1 wherein the arms each defines a profile when in the expanded configuration, the profile selected from the group consisting of curves, semi-circles, semi-ellipses, figure-eights, U-shapes, and combinations thereof.

14. The anchor of claim 1 further comprising a loading mechanism in communication with the anchor, wherein the loading mechanism is adapted to indicate a loading condition upon the anchor.

15. The anchor of claim 1 further comprising a length of suture passing through the anchor.

16. The anchor of claim 15 further comprising a locking mechanism adapted to pass the anchor in a first direction relative to the length of suture.

17. The anchor of claim 16 wherein the locking mechanism is further adapted to impart a locking force upon the length of suture when the anchor is urged in a second direction opposite to the first direction.

18. The anchor of claim 1 wherein the anchor is adapted to be delivered through a hollow member when in the delivery configuration.

19. The anchor of claim 1 further comprising a coating or covering disposed over at least a portion of the anchor.

20. The anchor of claim 19 wherein the coating or covering is disposed over at least a portion of an outer surface of each arm.

21. The anchor of claim 1 further comprising a covering disposed over the anchor.

22. A tissue securement system, comprising:

an anchor having a proximal collar, a distal collar, and a plurality of deformable arms each extending therebetween;

a length of suture disposable through the anchor;

a hollow member adapted to contain the anchor in a delivery configuration, wherein the anchor is adapted to self-configure from the delivery configuration to an expanded configuration externally of the hollow member, and

wherein the anchor is further adapted to exert a substantially constant force against a tissue surface in the expanded configuration over a range of deflections when the proximal and distal collars are moved relative to one another.

23. The anchor of claim 22 wherein the proximal and distal collars each define a lumen therethrough.

24. The anchor of claim 22 wherein the anchor is comprised of a shape memory or superelastic alloy.

25. The anchor of claim 22 wherein the anchor is comprised of nitinol.

26. The anchor of claim 22 wherein the plurality of deformable arms define a space between adjacent arms for contact against the tissue surface.

27. The anchor of claim 22 wherein the deformable arms are parallel.

28. The anchor of claim 22 wherein the deformable arms each define a non-uniform cross-section along a length of the arm.

29. The anchor of claim 28 wherein each of the arms is tapered along its length.

30. The anchor of claim 22 wherein each of the arms define at least a proximal section, a distal section, and a middle section.

31. The anchor of claim 30 wherein the proximal and distal sections have uniform cross-sections.

32. The anchor of claim 22 wherein the arms number at least two.

33. The anchor of claim 22 wherein the arms each defines a profile when in the expanded configuration, the profile selected from the group consisting of curves, semi-circles, semi-ellipses, figure-eights, U-shapes, and combinations thereof.

34. The anchor of claim 22 further comprising a loading mechanism in communication with the anchor, wherein the loading mechanism is adapted to indicate a loading condition upon the anchor.

35. The anchor of claim 22 further comprising a locking mechanism adapted to pass the anchor in a first direction relative to the length of suture.

36. The anchor of claim 35 wherein the locking mechanism is further adapted to impart a locking force upon the length of suture when the anchor is urged in a second direction opposite to the first direction.

37. The anchor of claim 22 wherein the hollow member comprises a needle.

38. The anchor of claim 22 further comprising a coating or covering disposed over at least a portion of the anchor.

39. The anchor of claim 38 wherein the coating or covering is disposed over at least a portion of an outer surface of each arm.

40. The anchor of claim 22 further comprising a covering disposed over the anchor.