SEGMENTED INTRAMEDULLARY STRUCTURE

• US 20080287951A1
• Filed: 03/21/2008
• Published: 11/20/2008
• Est. Priority Date: 03/22/2007
• Status: Active Grant

• Current Assignee: Arthrex Incorporated
• Original Assignee: Sonoma Orthopedic Products Incorporated (Arthrex Incorporated)
• Inventors: Larsen, Charles E., Justin, Daniel F., Stoneburner, James D., Harmon, Matthew T., Trip, Roelof, Creger, Carlyle J., Mohr, Karen E.
• Granted Patent: US 8,430,879 B2
• Time in Patent Office: Days
• US Class Current: 606/63
• CPC Class Codes: A61B 17/1717 for applying intramedullary nails or pins
• CPC Class Codes: A61B 17/1725 for applying transverse screws or pins through intramedullary nails or pins
• CPC Class Codes: A61B 17/7208 Flexible pins, e.g. ENDER pins
• CPC Class Codes: A61B 17/7266 with fingers moving radially outwardly
• CPC Class Codes: A61B 17/7283 with special cross-section of the nail
• CPC Class Codes: A61B 17/8869 Tensioning devices
• CPC Class Codes: A61B 2017/922 Devices for impaction, impact element
• CPC Class Codes: A61B 5/107 Measuring physical dimensions, e.g. size of the entire body or parts thereof
• CPC Class Codes: A61B 5/4504 Bones A61B5/4547 takes precedence
• CPC Class Codes: Y10T 29/49826 Assembling or joining
• CPC Class Codes: Y10T 29/53796 Puller or pusher means, contained force multiplying operator

Abstract

An implantable intramedullary fixation structure adapted to be received in the intramedullary canal of a long bone is disclosed comprising a plurality of elongated segments. Each segment has a first end and a complementarily-shaped second end such that the first end of a segment cooperatively engages the second end of an adjacent segment. The segments define a guide aperture so as to be receivable over a guide for positioning in the intramedullary canal.

Claims

1. An implantable intramedullary fixation structure adapted to be received in the intramedullary canal of a long bone comprising:

a plurality of elongated segments, each segment having a first end and a complementarily-shaped second end such that the first end of a segment cooperatively engages the second end of an adjacent segment, the segments defining a guide aperture so as to be receivable over a guide for positioning in the intramedullary canal.

2. The intramedullary structure of claim 1 further comprising a tensioning member extending the length thereof to apply a compressive force along the longitudinal axis of the structure.

3. The intramedullary structure of claim 1 further comprising at least one fastener received in at least one of the segments for securing the structure in place in the long bone.

4. The intramedullary structure of claim 1 further comprising hardenable surgical fluid for securing the structure in place in the long bone.

5. The intramedullary structure of claim 1 wherein the complementarily-shaped ends of the elongated segments permit relative movement between adjacent segments substantially only axially and in a single plane.

6. The intramedullary structure of claim 5 wherein the complementarily-shaped ends comprise four surfaces, a first and second surface being substantially planar in line and substantially parallel planes, a third surface being substantially planar in line and a plane substantially perpendicular to the first and second surfaces, and a fourth surface defining a plane generally perpendicular to the first and second surfaces and oblique to the third surface.

7. The intramedullary structure of claim 6 wherein the fourth surface of the elongated segments comprises a plurality of steps.

8. The intramedullary structure of claim 1 wherein adjacent elongated segments are secured to each other.

9. The intramedullary structure of claim 8 wherein adjacent elongated segments are secured to each other by a hinge pin mounted to a segment and received in an elongated slot and an adjacent segment.

10. The intramedullary structure of claim 1 further comprising a radially-expandable member received distally of a distal-most segment and having a cable secured thereto, the cable residing in the guide aperture and extending through the intramedullary structure.

11. The intramedullary structure of claim 10 wherein the expandable member comprises an expander having a plurality of depending legs and a wedge, the cable being secured to the wedge so that when the cable is tensioned, the wedge spreads the legs of the expander radially outwardly.

12. An assembly for tensioning a surgical cable, the assembly comprising:

a cable having a first location connectable to an implant;

a locking feature configured to circumferentially engage the cable to lock onto a second location on the cable;

a tensioner configured to engage the locking feature, wherein the tensioner is actuable to move the locking feature relative to the first location to regulate tension on the cable between the first location and the second location when the first location is connected to the implant and the second location is locked in the locking feature; and

a locking mechanism actuator configured to actuate a locking mechanism to lock onto a third location on the cable.

13. The assembly of claim 12, wherein the implant is a segmented intramedullary fracture fixation device.

14. The assembly of claim 12, wherein the third location is between the first location and the second location.

15. An assembly for tensioning a surgical cable, the assembly comprising:

a cable having a first location connectable to an implant;

a locking feature configured to engage the cable to lock onto a second location on the cable;

a tensioner configured to engage the locking feature, wherein the tensioner is actuable to move the locking feature relative to the first location to regulate tension on the cable between the first location and the second location when the first location is connected to the implant and the second location is locked in the locking feature; and

a locking mechanism actuator configured to reversibly actuate a locking mechanism to lock and unlock onto a third location on the cable, wherein the locking mechanism actuator is contained within the tensioner.

16. The assembly of claim 15, wherein the implant is a segmented intramedullary fracture fixation device.

17. The assembly of claim 15, wherein the third location is between the first location and the second location.

18. The assembly of claim 15, wherein the locking feature is configured to circumferentially engage the cable.

19. A method for tensioning a surgical cable, the method comprising:

connecting a first location on a cable to an implant;

locking a locking feature onto a second location on the cable, wherein the locking feature circumferentially engages the cable to lock onto the cable;

actuating a tensioner to regulate the tension on the cable between the first location and the second location; and

locking a locking mechanism onto a third location on the cable.

20. The method of claim 19, wherein the implant is a segmented intramedullary fracture fixation device.

21. The method of claim 19, wherein the third location is between the first location and the second location.

22. The method of claim 19, further comprising actuating the locking mechanism actuator to lock the locking mechanism onto the third location on the cable after regulating the tension on the cable.

23. A method for tensioning a surgical cable, the method comprising:

connecting a first location on a cable to an implant;

locking a locking feature onto a second location on the cable, wherein the locking feature circumferentially engages the cable to lock onto the cable;

actuating a tensioner to regulate the tension on the cable between the first location and the second location; and

locking a locking mechanism onto a third location on the cable.

24. The method of claim 23, wherein the implant is a segmented intramedullary fracture fixation device.

25. The method of claim 23, wherein the third location is between the first location and the second location.

26. The method of claim 23, further comprising actuating the locking mechanism actuator to lock the locking mechanism onto the third location on the cable after regulating the tension on the cable.