Radially expandable intramedullary nail

• US 20020165544A1
• Filed: 05/10/2002
• Published: 11/07/2002
• Est. Priority Date: 11/11/1999
• Status: Active Grant

• Current Assignee: Synthes USA LLC (Johnson & Johnson)
• Original Assignee: Synthes USA LLC (Johnson & Johnson)
• Inventors: Hehli, Markus, Perren, Stephan
• Granted Patent: US 6,736,818 B2
• Time in Patent Office: Days
• US Class Current: 606/63
• CPC Class Codes: A61B 17/7266 with fingers moving radially outwardly

Abstract

The invention is related to an intramedullary nail for fixation of a fractured bone having a medullary canal. The intramedullary nail may comprise a first radially expandable section provided in a proximal section adjacent to the head of the intramedullary nail, a second radially expandable section provided in the distal section adjacent to the tip of the intramedullary nail, and a non-expandable middle section provided between said two radially expandable sections of the intramedullary nail. The head may provide a distraction mechanism, by means of which said two radially expandable sections are distractible transverse to said longitudinal axis.

Claims

1. An intramedullary nail having a head, a tip, and a longitudinal axis for fixation of a fractured bone having a medullary canal, the intramedullary nail comprising:

a first radially expandable section adjacent to the head;

a second radially expandable section adjacent to the tip; and

a non-expandable section disposed between the first and second radially expandable sections.

2. The intramedullary nail of claim 1, further comprising a hollow cylindrical sleeve extending along the longitudinal axis and surrounding a locking element coaxially to the longitudinal axis.

3. The intramedullary nail of claim 1, wherein the head is provided with a distraction mechanism, and the first and second radially expandable sections are distractible transverse to said longitudinal axis.

4. The intramedullary nail of claim 1, wherein the non-expandable section comprises at least one unslotted tubular member.

5. The intramedullary nail of claim 1, wherein the non-expandable section has a length in the range of about 10 mm to 25 mm.

6. The intramedullary nail of claim 4, wherein the non-expandable section of the intramedullary nail has a length in the range of about 15 mm to about 22 mm.

7. The intramedullary nail of claim 2, wherein the expandable and nonexpandable sections are tubular members that are positioned over the sleeve in sequence and are secured on the sleeve by a nut, the sequence of positioning the tubular members comprising:

a slotted tubular member, an unslotted tubular member, a slotted tubular member, and an unslotted tubular member.

8. The intramedullary nail of claim 7, wherein the nut comprises means for engagement of a driving means.

9. The intramedullary nail of claim 7, wherein the means for engagement of a driving means comprises hexagonal sides.

10. The intramedullary nail of claim 2, wherein the sleeve comprises means for engagement of a holding means.

11. The intramedulllary nail of claim 10, wherein the means for engagement of a holding means is a slot.

12. The intramedullary nail of claim 12, wherein the locking element comprises a shaft with a thread in a proximal section and a projection forming an abutment in the distal section.

13. The intramedullary nail of claim 12, wherein a distal section of the sleeve provides a slot penetrating the side wall through to a bore and the projection of the locking element is movable slide within said slot in the direction of the longitudinal axis.

14. The intramedullary nail of claim 2, wherein the first and second radially expandable sections each comprise a slotted tubular member..

15. The intramedullary nail of claim 14, wherein the slotted tubular member are configured to be slidable on the sleeve.

16. The intramedullary nail of claim 15, wherein the distraction mechanism comprises a thread on the locking element adjacent to the head and a nut with an interior thread corresponding with the thread on the locking element.

17. The intramedullary nail of claim 16, wherein the nut comprises means for engagement of a driving means.

18. The intramedullary nail of claim 2, wherein the locking element comprises means for engagement of a holding means.

19. The intramedullary nail of claim 18, wherein the distraction mechanism comprises a thread on the locking element adjacent to the head and an end cap with an interior thread corresponding with the thread on the locking element.

20. The intramedullary nail of claim 19, wherein an end cap comprises means for engagement of a driving means.