Implant system for bone fixation

Patent metadata

Field	Value
Publication number	US-10034696-B2
Application number	US-201213983841-A
Country	US
Kind code	B2
Filing date	Feb 8, 2012
Priority date	Feb 8, 2011
Publication date	Jul 31, 2018
Grant date	Jul 31, 2018

Abstract

An implant system for use in orthopedic surgery for fixation of bone includes an intramedullary nail and a coupling unit. The intramedullary nail has a medial side, a lateral side and a proximal portion defining a longitudinal axis. The proximal portion includes a bore defining a first axis substantially parallel to the longitudinal axis of the proximal portion and a transverse bore configured to receive a bone fastener. The coupling unit is movably arranged within the bore of the proximal portion and includes one or more bone fastener engagement members at one or both of the lateral side and the medial side of the intramedullary nail.

First claim

The invention claimed is:

1. An implant system for use in orthopaedic surgery for fixation of bone, comprising:
a bone fastener;
an intramedullary nail with a medial side, a lateral side and a proximal portion defining a central longitudinal axis, wherein the proximal portion includes an axial bore defining a first axis substantially parallel to the longitudinal axis of the proximal portion and at least one transverse bore having a central longitudinal axis extending from the medial side to the lateral side of the proximal portion configured to receive the bone fastener;
a coupling unit configured to be movably arranged within the axial bore of the proximal portion and the coupling unit having a base member formed at a proximal end thereof, including first and second bone fastener engagement pins extending from the base member each engagement pin having a central longitudinal axis, the first bone fastener engagement pin located at the lateral side of the intramedullary nail and the second bone fastener engagement pin located at the medial side of the intramedullary nail, wherein the medial and lateral sides generally lie within a plane including the central longitudinal axis of the proximal portion and a central longitudinal axis of the transverse bore, the central longitudinal axis of the first and second bone fastener engagement pins lying in the plane;
wherein the first and second bone fastener engagement pins are interconnected by the base member and have distal ends for engaging the bone fastener; and
further comprising a first and second guiding structure in the axial bore of the proximal nail portion respectively slidably engaging the first and second bone fastener engagement pins, the first and second guiding structures are formed as a first and second axially extending recesses formed in a wall of the proximal portion axial bore, the axially extending recesses guiding the first and second bone fastener engagement pins in the axial direction into the bone fastener, the engagement of the first and second bone fastener engagement pins and the recesses preventing the rotation of the coupling unit about the central longitudinal axis during axial movement of the coupling unit prior to the first and second bone fastener engagement pins distal ends engaging the bone fastener.

2. The implant system according to claim 1 , wherein the proximal portion is adapted to guide the coupling unit with the first and second bone fastener engagement pins have a longitudinal axis extending in a direction substantially parallel to the longitudinal axis of the proximal portion.

3. The implant system according to claim 1 , wherein, each axially extending recess defining a central longitudinal axis substantially parallel to the longitudinal axis of the proximal portion.

4. The implant system according to claim 3 , wherein the longitudinal axis of the first and second guiding structures are oriented eccentrically with respect to the longitudinal axis of the proximal portion.

5. The implant system according to claim 3 , wherein the first and second axially extending recesses are formed as grooves or bores.

6. The implant system according to claim 3 , wherein the bore of the proximal portion and the first and second axially extending recesses are arranged adjacent to each other.

7. The implant system according to claim 3 , wherein the first and second axially extending recesses are respectively located at the lateral side and the medial side of the intramedullary nail.

8. The implant system according to claim 1 , wherein the coupling unit first bone fastener engagement pin and second bone fastener engagement pin lie on a line that extends along the plane including the longitudinal axis of the proximal portion and a longitudinal axis of the transverse bore, wherein the line is spaced apart from the longitudinal axis of the proximal portion in a medial direction and a lateral direction of the intramedullary nail.

9. The implant system according to claim 1 , wherein the axial bore of the proximal portion is located at the medial side or at the lateral side of the intramedullary nail or is centrally located with respect to the longitudinal axis of the proximal portion.

10. The implant system according to claim 1 , wherein the coupling unit is configured to urge, upon moving of the coupling unit toward a distal portion of the intramedullary nail, the first and second bone fastener engagement pins in the direction of the longitudinal axis of the proximal portion towards the distal portion.

11. The implant system according to claim 1 , wherein each of the first and second bone fastener engagement pins define a longitudinal axis intersecting a longitudinal axis of the transverse bore.

12. The implant system according to claim 1 , wherein the first and second bone fastener engagement pins are eccentrically arranged on a drive member of the coupling unit.

13. The implant system according to claim 1 , wherein the coupling unit includes a drive member for moving the coupling unit within the axial bore of the proximal portion.

14. The implant system according to claim 13 , wherein the drive member has an external thread for threadable engagement with the intramedullary nail.

15. The implant system according to claim 14 ,
wherein the axial bore of the proximal portion of the intramedullary nail includes an internal thread, wherein the external thread of the drive member is configured to mate with the internal thread of the axial bore.

16. The implant system according to claim 13 , wherein the drive member further includes a ring arranged in a circumferential groove of the drive member.

17. The implant system according to claim 13 , wherein the drive member includes a drive transmitting portion, and the first and second bone fastener engagement pins include a groove arranged in a direction transverse to the longitudinal direction of the first and second bone fastener engagement pins, wherein the drive transmitting portion movably engages within the groove of the first and second bone fastener engagement pins.

18. The implant system according to claim 17 , wherein the drive transmitting portion is rotatably supported in the groove of the first and second bone fastener engagement pins.

19. The implant system according to claim 13 , wherein the drive member includes a drive transmitting portion, and the first and second bone fastener engagement pins are arranged on a base member, wherein the drive transmitting portion movably engages the base member.

20. The implant system according to claim 1 , further comprising a retainer arranged in the proximal portion of the intramedullary nail, wherein the range of motion of the coupling unit in the proximal direction is limited by the retainer.

21. The implant system according to claim 1 , further comprising the bone fastener, wherein the first and second bone fastener engagement pins engage the bone fastener to prevent rotation of the bone fastener about a longitudinal axis of the bone fastener.

22. The implant system according to claim 1 , wherein the coupling unit is captively held within the proximal portion of the intramedullary nail.

23. The implant as set forth in claim 1 , wherein the proximal nail portion has a longitudinally extending part-cylindrical groove open to the axial bore extending along the medial side and along the lateral side of the proximal nail portion and wherein each medial and lateral engagement pin includes a cylindrical portion slidabl

Assignees

• Mueckter Helmut
• Stoltenberg Ingo
• Stryker European Holdings I Llc

Inventors

• Mueckter Helmut
• Stoltenberg Ingo

Classifications

• A61B17/725 Primary

  with locking pins or screws of special form · CPC title

• A61B17/744 Primary

  the longitudinal elements coupled to an intramedullary nail · CPC title

• A61B17/7233

  with special means of locking the nail to the bone · CPC title