Variable stiffness hammertoe K-wire and methods for use

Patent metadata

Field	Value
Publication number	US-11504172-B2
Application number	US-201916671803-A
Country	US
Kind code	B2
Filing date	Nov 1, 2019
Priority date	Nov 1, 2018
Publication date	Nov 22, 2022
Grant date	Nov 22, 2022

Abstract

The present disclosure provides an apparatus comprising a wire having a first end and a second end opposite the first end. A first portion of the wire including the first end comprises a malleable region that is configured to remain deformed after bending, and a second portion of the wire including the second end comprises a superelastic region that is configured to return to a straight configuration after bending.

First claim

The invention claimed is:

1. An apparatus comprising:
a wire having a first portion including a first end and a second portion including a sharp tapered second end opposite the first end, wherein the first portion of the wire is configured to transition from a straight configuration along a longitudinal axis of the wire to a bent configuration in response to a bending applied to the first portion when positioned outside of a body of a patient in ambient air, wherein the first portion is configured to remain in the bent configuration after release of the bending, and wherein the second portion of the wire comprises a region that is superelastic in ambient air and is configured to return to the straight configuration a along the longitudinal axis of the wire after bending of the superelastic region when the second portion is positioned inside the body of the patient.

2. The apparatus of claim 1 , wherein a length of the first portion of the wire is less than a length of the second portion of the wire.

3. The apparatus of claim 1 , wherein a ratio of a length of the first portion of the wire to a length of the second portion of the wire is about 3:1 to about 1:3.

4. The apparatus of claim 1 , wherein a length of the first portion of the wire ranges from about 10 mm to about 600 mm, and wherein a length of the second portion of the wire is about 10 mm to about 300 mm.

5. The apparatus of claim 1 , wherein a diameter of the wire is about 0.6 mm to about 4 mm.

6. The apparatus of claim 1 , wherein a diameter of the first portion of the wire is equal to a diameter of the second portion of the wire.

7. The apparatus of claim 1 , wherein a diameter of the first portion of the wire is different than a diameter of the second portion of the wire.

8. The apparatus of claim 1 , wherein the first portion of the wire has an austenitic start temperature greater than 22° C.

9. The apparatus of claim 1 , wherein the second portion of the wire has an austenitic finish temperature less than 37° C.

10. The apparatus of claim 9 , wherein the austenitic finish temperature of the second portion of the wire ranges from about −5° C. to about 26° C.

11. The apparatus of claim 1 , wherein a loading plateau of the first portion of the wire is less than about 45 ksi, and wherein a loading plateau of the second portion of the wire ranges from about 55 ksi to about 80 ksi.

12. The apparatus of claim 1 , further comprising a transition zone marker positioned on the wire between the first portion and the second portion.

13. The apparatus of claim 1 , wherein the first portion and/or the second portion of the wire includes a marker.

14. The apparatus of claim 1 , wherein the first portion of the wire includes one or more measurement markings indicating a length of the first portion.

15. The apparatus of claim 1 , wherein the wire comprises a shape memory alloy.

16. A method comprising:
introducing the second end of the wire of claim 1 into a joint; and
cutting the first end of the wire.

17. The method of claim 16 , wherein the first end of the wire is malleable.

18. The method of claim 17 , further comprising:
bending the first portion of the wire to permanently deform the first portion such that the first end of the wire has a non-zero angle with respect to the second end of the wire.

19. The method of claim 16 , further comprising:
positioning the second end of the wire through a lumen in a hammertoe implant; and
positioning the hammertoe implant in the joint prior to cutting the first end of the wire.

20. The method of claim 16 , further comprising:
removing the wire from the joint.

Assignees

• Arthrex Inc

Inventors

• Powell Chris
• Fonte Matthew
• Devaney Robert
• Fein Paul
• Weaver Vincent

Classifications

• A61F2/4225

  for feet, e.g. toes · CPC title

• A61B17/848 Primary

  Kirschner wires, i.e. thin, long nails · CPC title

• A61B17/7291 Primary

  for small bones, e.g. in the foot, ankle, hand or wrist · CPC title

• A61B2017/00946

  malleable · CPC title

• A61F2002/4228

  for interphalangeal joints, i.e. IP joints · CPC title