Intramedullary nail system

• US 6,524,313 B1
• Filed: 09/28/2000
• Issued: 02/25/2003
• Est. Priority Date: 10/14/1999
• Status: Expired due to Term

• Current Assignee: Pega Medical, Inc. (Orthopediatrics Corporation)
• Original Assignee: Pega Medical, Inc. (Orthopediatrics Corporation)
• Inventors: Dujovne, Ariel, Duval, Pierre, Fassier, François
• Primary Examiner(s): Robert, Eduardo C.
• Application Number:
  US09/671,164
• Time in Patent Office: 880 Days
• Field of Search: 606/60, 606/72, 606/73, 606/62, 606/63
• US Class Current: 606/63
• CPC Class Codes: A61B 17/72 Intramedullary pins, nails or other devices A61B17/744 takes precedence
• CPC Class Codes: A61B 17/7216 for bone lengthening or compression A61B17/7258 takes precedence
• CPC Class Codes: A61B 17/7233 with special means of locking the nail to the bone

Abstract

An intramedullary nail system includes a telescopic nail assembly for use in fixation of long bone fractures. The nail assembly includes a female hollow nail that is attached to the proximal cortex of the femur, and a male solid nail that is attached to the distal cortex. Anchorage of the telescopic nail assembly is achieved through screw type fixation. The intramedullary nail system has a built-in feature that allows for extension of its length as bone structures heal and normal patient growth occurs, which is particularly advantageous to be used for children above two years of age and below 65 kilograms of body weight.

Claims

1. An intramedullary nail assembly for use in fixation of long bone fractures comprising:

a telescopic rod having two opposed ends and including a female component and a male component telescopingly interconnected to permit axial movement of the ends relative to each other; and

means for anchoring each end of the telescopic rod to either end of a fractured long bone when the telescopic rod is implanted in the long bone and extends longitudinally through a length of the bone so that the length of the telescopic rod is extendable as the bone heals and bone growth occurs.

2. The intramedullary nail assembly as claimed in claim 1, wherein the anchoring means comprises a thread fastening mechanism at each end of the telescopic rod.

3. The intramedullary nail assembly as claimed in claim 2, wherein the male component comprises a self-tapping screw fixed on the male component forming one of the opposed ends of the telescopic rod and the female component comprises an external thread fixed on the female component forming the other end of the telescopic rod.

4. The intramedullary nail assembly as claimed in claim 3, wherein the male component is detachable from the female component so that the male component is adapted to be implanted in the bone and anchored in one end of the bone using the self-tapping screw before the female component is implanted.

5. The intramedullary nail assembly as claimed in claim 1, wherein each of the male and female components has a length thereof such that the nail assembly is adapted to be attached to bony structures without disrupting a bone growth plate.

6. An intramedullary nail assembly for use in fixation of long bone fractures comprising:

an elongated tube having one end thereof formed with a bone engagement means;

a rod having one end thereof formed with a bone engagement means;

the rod being slidably and detachably received in the elongated tube to form a telescopic nail assembly with the bone engagement means at opposed ends thereof; and

whereby the telescopic nail assembly is adapted to be implanted in a fractured long bone, extending longitudinally through a length of the bone with the bone engagement means at each end of the telescopic nail assembly anchored in either end of the bone and being extendable as the bone heals and bone growth occurs.

7. The intramedullary nail assembly as claimed in claim 6, wherein the bone engagement means is an external thread.

8. The intramedullary nail assembly as claimed in claim 7, wherein the thread formed at the end of the rod is a self-tapping screw.

9. The intramedullary nail assembly as claimed in claim 8, wherein the self-tapping screw has a diameter as large as an external diameter of the elongated tube.

10. The intramedullary nail assembly as claimed in claim 8, wherein the rod includes a connector located close to the self-tapping screw so that a driving tool is enabled to detachably connect the connector to apply a torque to the rod for anchoring the self-tapping screw in the bone.

11. The intramedullary nail assembly as claimed in claim 7, wherein the thread at the end of the tube has a diameter larger than an external diameter of the elongated tube.

12. The intramedullary nail assembly as claimed in claim 7, wherein the elongated tube includes a connector located close to the external thread so that a driving tool is enabled to detachably connect the connector to apply a torque to the tube for anchoring the external thread in the bone.

13. The intramedullary nail assembly as claimed in claim 6, wherein the nail assembly is made from Ti alloy.

14. The intramedullary nail assembly as claimed in claim 6, wherein the nail assembly is made from medical grade stainless steel.

15. A method of treating a fracture in a long bone having an intramedullary canal comprising steps of:

inserting a male nail having a rod and a first bone engagement portion at a forward end of the rod through the intramedullary canal into the bone until the first bone engagement portion is anchored in either one end of the bone, with the rod spanning the fracture;

inserting a female nail having an elongated tube and a second bone engagement portion at a rearward end of the tube through the canal into the bone, to receive a rearward end of the rod sliding into the tube until the second bone engagement portion is anchored in an end of the bone opposite to the end where the first bone engagement portion is anchored so that the male and female nails are axially extendable relative to each other when bone structures heal and bone growth occurs.

16. The method as claimed in claim 15, wherein the first bone engagement portion is a self-tapping screw anchored in a distal epiphysis of the bone and the second bone engagement portion of the female nail is anchored in a greater trochanter.

17. The method as claimed in claim 16, wherein the second bone engagement portion of the female nail is anchored in a place beyond a growth plate of bony structures.

18. The method as claimed in claim 17, wherein the male and female nails are inserted through the greater trochanter of the bone respectively.

19. The method as claimed in claim 17, wherein the male nail is inserted through a postero-lateral approach.

20. The method as claimed in claim 16, wherein the self-tapping screw has a diameter as large as an external diameter of the tube to facilitate the insertion of the female nail.

21. The method as claimed in claim 16, comprising a step of using a driving tool detachably connected to a connector on the rod located close to the self-tapping screw to apply a torque to the male nail to anchor the self-tapping screw in the bone.

22. The method as claimed in claim 16, comprising a step of using a driving tool detachably connected to a connector at the rearward end of the tube to apply a torque to the female nail to anchor the external thread in the bone.

23. The method as claimed in claim 15, comprising a step of reaming at least a portion of the intramedullary canal before the insertion of the male nail to facilitate the insertion.