Intramedullary rod with spiraling flutes

• US 20050277936A1
• Filed: 06/11/2004
• Published: 12/15/2005
• Est. Priority Date: 06/11/2004
• Status: Active Grant

• Current Assignee: Synthes USA LLC (Johnson & Johnson)
• Original Assignee: Synthes USA LLC (Johnson & Johnson)
• Inventors: Roth, Christoph Andreas, Siravo, Mark
• Granted Patent: US 7,771,428 B2
• Time in Patent Office: Days
• US Class Current: 606/62
• CPC Class Codes: A61B 17/72 Intramedullary pins, nails or other devices A61B17/744 takes precedence
• CPC Class Codes: A61B 17/7233 with special means of locking the nail to the bone
• CPC Class Codes: A61B 17/7241 the nail having separate elements through which screws pass
• CPC Class Codes: A61B 17/7283 with special cross-section of the nail
• CPC Class Codes: A61B 17/744 the longitudinal elements coupled to an intramedullary nail

Abstract

This invention relates generally to devices, systems and methods for the internal fixation of bone fractures, and particularly, to intramedullary fracture fixation devices such as those used in, for example, the treatment of long bone fractures. An IM rod preferably is provided with multiple curved sections in different planes preferably designed to conform with the long bones of a patient, both during insertion and in the rod'"'"'s final position in the long bone. In addition, the overlap of portions of the curved sections results in a co-planar curvature of portions of the IM rod which assist in the insertion process by guiding the proper rotation of the IM rod as it is inserted into the bone. Spiraling flutes extending down the distal portion of the rod also assist in properly guiding and orienting the rod about its longitudinal axis during insertion such that the appropriate segment of the curved rod conforms with the appropriate portion of the long bone at the appropriate place.

Claims

1. An intramedullary rod for use in the treatment of femoral fractures comprising:

an elongated rod with a longitudinal axis, a head and a stem; and

at least one transverse hole extending through the rod;

wherein the elongated rod includes at least two curved sections in a lateral-medial plane, and at least one curved section in an anterior-posterior plane.

2. The intramedullary rod of claim 1, wherein:

the at least two curved sections in the lateral-medial plane comprise a first radius of curvature and a second radius of curvature, the first radius of curvature being different than the second radius of curvature.

3. The intramedullary rod of claim 2, wherein the curved section in the anterior-posterior plane comprises a third radius of curvature, the third radius of curvature being different than the first radius of curvature.

4. The intramedullary rod of claim 2, wherein the second radius of curvature is larger than the first radius of curvature.

5. The intramedullary rod of claim 3, wherein the third radius of curvature is larger than the first and second radii of curvature.

6. The intramedullary rod of claim 3, wherein the first curved section in the lateral-medial plane is separated from the second curved section in the lateral-medial plane by a substantially straight section.

7. The intramedullary rod of claim 6, wherein the first curved section extends for about 10 mm to about 60 mm.

8. The intramedullary rod of claim 7, wherein the second curved section extends for about 10 mm to about 220 mm.

9. The intramedullary rod of claim 6, further comprising a plurality of flutes located along at least a portion of the stem and extending in a spiral down the stem;

wherein at least one of the curved sections in the lateral-medial plane overlaps with the at least one curved section in the anterior-posterior plane.

10. The intramedullary rod of claim 9, wherein the orientation of the flutes changes by about a 90 degree angular rotation with respect to the longitudinal axis of the rod.

11. The intramedullary rod of claim 2, wherein:

the first curved section has a radius of curvature of between 100 mm and 500 mm;

the second curved section has a radius of curvature of between 100 mm and 1500 mm; and

the third curved section has a radius of curvature of between 500 mm and 2500 mm.

12. The intramedullary rod of claim 1, wherein the at least one transverse hole comprises:

a pair of holes located in the head portion having substantially parallel axes oriented at a first angle with respect to said longitudinal axis of said rod; and

a bore located in the head portion having an axis oriented at a second angle with respect to the longitudinal axis of the rod.

13. The intramedullary rod of claim 12 further comprising an elongated hole located in the stem portion having an axis oriented at an angle with respect to the longitudinal axis of the rod.

14. The intramedullary rod of claim 13, wherein the angle of the elongated hole is substantially the same as the bore.

15. The intramedullary rod of claim 13, wherein the angle of the elongated hole is different than the angle of the bore.

16. The intramedullary rod of claim 12, further comprising:

at least two distal holes located in at least a portion of the stem with axes that are oriented at about 85°

to about 95°

to the longitudinal axis of the rod and angularly offset from one another about the longitudinal axis.

17. The intramedullary rod of claim 16, wherein the distal holes comprise a first distal hole angularly offset about the longitudinal axis from the head hole axes, and a second distal hole angularly offset in the same direction as the first distal hole by a larger angular offset about the longitudinal axis from the head hole axes.

18. The intramedullary rod of claim 11, wherein the rod has a bore extending along its longitudinal axis.

19. The intramedullary rod of claim 6 wherein at least one of the curved sections in the lateral-medial plane overlaps with at least one of the curved sections in the anterior-posterior plane.

20. An apparatus for internal fixation of a fracture comprising:

an elongated rod with a head, a stem, a longitudinal axis with at least one curved segment located in a lateral-medial plane, and at least one curved segment located in an anterior-posterior plane;

at least one hole extending transversely to the longitudinal axis through the rod; and

a plurality of spiraling flutes located along at least a portion of said rod.

21. The apparatus for internal fixation of a fracture of claim 20 additionally comprising a second curved segment located in the lateral-medial plane.

22. The apparatus for internal fixation of a fracture of claim 21 wherein the at least one curved segment located in the anterior-posterior plane overlaps the second curved segment located in the lateral-medial plane.

23. The apparatus for internal fixation of a fracture of claim 22 wherein the at least one curved segment and the second curved segment located in the lateral-medial plane are separated by a non-curved segment.

24. The apparatus for internal fixation of a fracture of claim 23 wherein:

the at least one curved segment located in a lateral-medial plane comprises a first radius of curvature;

the second curved segment located in a lateral-medial plane comprises a second radius of curvature; and

the first radius of curvature is different than the second radius of curvature.

25. The apparatus for internal fixation of a fracture of claim 24 wherein the at least one curved segment located in the anterior-posterior plane comprises a third radius of curvature, the third radius of curvature being different than the first radius of curvature.

26. The apparatus for internal fixation of a fracture of claim 25 wherein the second radius of curvature is larger than the first radius of curvature.

27. The apparatus for internal fixation of a fracture of claim 24 wherein the third radius of curvature is larger than the first and second radii of curvature.

28. The apparatus for internal fixation of a fracture of claim 24 wherein the at least one curved segment in the lateral-medial plane extends for about 10 mm to about 60 mm.

29. The apparatus for internal fixation of a fracture of claim 28 wherein the second curved segment in the lateral-medial plane extends for about 10 mm to about 220 mm.

30. The apparatus for internal fixation of a fracture of claim 23 wherein the orientation of the flutes changes by about a 90 degree angular rotation with respect to the longitudinal axis of the rod.

31. The apparatus for internal fixation of a fracture of claim 25, wherein:

the first radius of curvature is between 100 mm and 500 mm;

the second radius of curvature is between 100 mm and 1500 mm; and

the third radius of curvature is between 500 mm and 2500 mm.

32. The apparatus for internal fixation of a fracture of claim 23 wherein the at least one transverse hole comprises:

a pair of holes located in the head having substantially parallel axes oriented at a first angle with respect to the longitudinal axis of the rod; and

a bore located in the head having an axis oriented at a second angle with respect to the longitudinal axis of the rod.

33. The apparatus for internal fixation of a fracture of claim 32 further comprising an elongated hole through the rod having an axis oriented at an angle with respect to the longitudinal axis of the rod.

34. The apparatus for internal fixation of a fracture of claim 33, further comprising:

at least two distal holes located in the stem with axes that are oriented at about 85°

to 95°

to the longitudinal axis of the rod and angularly offset from one another about the longitudinal axis.

35. A method for the treatment of femoral fractures comprising:

creating an entry site at a location offset from the piriformis fossa of a femur;

providing an elongated rod with a longitudinal axis, at least one curved segment located in a lateral medial plane, at least one curved segment located in an anterior-posterior plane, at least one transverse hole extending through said rod, and a plurality of spiraling flutes located along at least a portion of said rod;

positioning the rod at the opening created at the entry site with an angular orientation different than its final position orientation;

inserting the rod through the opening at the entry site and into the medullary canal by twisting the rod during insertion;

inserting a fixation element through said transverse hole to engage bone tissue and secure said rod.

36. The method for the treatment of femoral fractures of claim 35, wherein the elongated rod additionally comprises a second curve located in the lateral-medial plane that is non-tangential with the at least one curved segment located in a lateral medial plane, resulting in a co-planar curvature through a portion of the rod which assists in rotating the elongated rod as it is inserted through the opening into the femur.

37. The method for the treatment of femoral fractures of claim 35 wherein prior to insertion, the rod is rotated about 90°

from its final insertion position and the rod is twisted about 90°

during the insertion step.

38. The method for the treatment of femoral fractures of claim 35 wherein the spiraling flutes rotate in a clockwise direction and the rod during insertion is twisted in a clockwise direction.

39. The apparatus for internal fixation of a fracture of claim 35 wherein the spiraling flutes rotate in a counter-clockwise direction and the rod during insertion is twisted in a counter-clockwise direction.