Dynamic bone fixation element

Patent metadata

Field	Value
Publication number	US-9827029-B2
Application number	US-201615133546-A
Country	US
Kind code	B2
Filing date	Apr 20, 2016
Priority date	Mar 13, 2012
Publication date	Nov 28, 2017
Grant date	Nov 28, 2017

Abstract

A dynamic bone fixation element can include a sleeve elongate along a first direction and a fixation member. The sleeve can define a channel that extends from a proximal end through to a distal end along the first direction. The channel has a first cross-sectional dimension. The fixation member has a head, a shaft extending from the head and elongate along a second direction, and an abutment member extending from the shaft and integral with the shaft, wherein the shaft extends through the channel such that the sleeve is captured between the abutment member and the head. At least a portion of the shaft that is within the channel has a second cross-sectional dimension that is less than the first cross-sectional dimension such that the fixation member is moveable with respect to the sleeve along a direction that has a directional component transverse to the first direction.

First claim

What is claimed:

1. A dynamic bone fixation element configured to couple a load carrier to bone, the dynamic bone fixation element comprising:
a sleeve that is elongate along a first direction, the sleeve defining a proximal end, a distal end spaced from the proximal end along the first direction, an outer surface that is configured to engage bone, and a channel that extends through the proximal end and at least toward the distal end along the first direction, at least a portion of the channel having a first cross-sectional dimension measured along a second direction, perpendicular to the first direction; and
a fixation member having a head, a shaft that extends from the head along the first direction, and an abutment member that extends from the shaft such that at least a portion of the abutment member faces the head, the shaft configured to extend into the channel such that at least a portion of the sleeve is captured between the abutment member and the head to thereby couple the fixation member to the sleeve,
wherein at least a portion of the shaft has a second cross-sectional dimension along the second direction, the second cross-sectional dimension being less than the first cross-sectional dimension such that the fixation member is moveable with respect to the sleeve along the second direction, and the channel and shaft have non-circular cross-sections that engage one another when the fixation member is coupled to the sleeve such that rotation of the fixation member causes the sleeve to rotate.

2. The dynamic bone fixation element of claim 1 , wherein the head defines a shoulder and the entire sleeve is configured to be captured between the abutment member and the shoulder such that the fixation member is moveable relative to the sleeve along the first direction.

3. The dynamic bone fixation element of claim 1 , wherein the head defines a shoulder and the entire sleeve is configured to be captured between the abutment member and the shoulder such that the fixation member is only moveable relative to the sleeve along the second direction.

4. The dynamic bone fixation element of claim 1 , wherein the non-circular cross-section of the channel has a cross-sectional dimension that is substantially equal to a cross-sectional dimension of the non-circular cross-section of the shaft.

5. The dynamic bone fixation element of claim 1 , wherein the cross-section of the channel is polygonal shaped and the cross-section of the shaft is polygonal shaped.

6. The dynamic bone fixation element of claim 1 , wherein the non-circular cross-section of the channel defines the first cross-sectional dimension, the non-circular cross-section of the shaft defines the second cross-sectional dimension, and the second cross-sectional dimension is less than the first cross-sectional dimension so as to define a non-zero gap between the shaft and an inner surface of the channel along the second direction.

7. The dynamic bone fixation element of claim 1 , wherein the abutment member comprises at least one flexible extension that is configured to flex inward as the shaft is passed through the channel.

8. The dynamic bone fixation element of claim 7 , wherein the abutment member comprises four flexible extensions that are configured to flex inward as the shaft is passed through the channel.

9. The dynamic bone fixation element of claim 1 , wherein the head includes an external thread that is configured to engage an internal thread of a bone plate.

10. The dynamic bone fixation element of claim 1 , wherein the outer surface of the sleeve carries a thread that is configured to engage bone.

11. The dynamic bone fixation element of claim 1 , wherein the sleeve defines a plurality of flexible legs that are configured to flex outwardly as the abutment member passes through the channel.

12. The dynamic bone fixation element of claim 1 , wherein the channel extends through proximal and distal ends of the sleeve.

13. A dynamic bone fixation element configured to couple a load carrier to bone, the dynamic bone fixation element comprising:
a sleeve that is elongate along a first direction, the sleeve defining a proximal end, a distal end spaced from the proximal end along the first direction, an outer surface that is configured to engage bone, and an inner surface that at least partially defines a channel, the channel extending through the proximal end, and further extending from the proximal end along the first direction toward the distal end, wherein at least a portion of the channel has a non-circular cross-section; and
a fixation member having a head, a shaft configured to extend from the head and into the channel, and an abutment member having at least a portion that protrudes radially outward relative to the shaft along a second direction that is substantially perpendicular to the first direction, wherein at least a portion of the shaft has a non-circular cross-section that engages the non-circular cross-section of the channel when the fixation member is coupled to the sleeve such that rotation of the fixation member causes the sleeve to rotate,
wherein the abutment member is configured to at least partially couple the fixation member to the sleeve such that both the abutment member and the head are moveable with respect to the sleeve along the second direction.

14. The dynamic bone fixation element of claim 13 , wherein the entire sleeve is captured between the head and the abutment member.

15. The dynamic bone fixation element of claim 13 , wherein the shaft has a surface that is spaced apart from the inner surface.

16. The dynamic bone fixation element of claim 13 , wherein the head defines a first abutment surface that is configured to abut the proximal end of the sleeve and the abutment member defines a second abutment surface that is configured to abut the distal end of the sleeve.

17. The dynamic bone fixation element of claim 13 , wherein the non-circular cross-section of the channel has a cross-sectional dimension that is substantially equal to a cross-sectional dimension of the non-circular cross-section of the shaft.

18. The dynamic bone fixation element of claim 13 , wherein the cross-section of the channel is polygonal shaped and the cross-section of the shaft is polygonal shaped such that rotation of the shaft causes the sleeve to rotate.

19. The dynamic bone fixation element of claim 13 , wherein the shaft has an outer surface at the non-circular cross-section of the shaft that is spaced from the inner surface of the sleeve at the non-circular cross-section of the channel so as to define a non-zero gap between the outer surface and the inner surface.

20. The dynamic bone fixation element of claim 13 , wherein the abutment member comprises at least one flexible extension that is configured to flex inward as the shaft is passed through the channel.

Assignees

• Depuy Synthes Products Inc

Inventors

• Hulliger Urs

Classifications

• A61B17/8625 Primary

  Shanks, i.e. parts contacting bone tissue · CPC title

• A61B17/84

  Fasteners therefor {or fasteners being internal fixation devices} · CPC title

• A61B17/8685 Primary

  comprising multiple separate parts · CPC title

• A61B17/686

  Plugs, i.e. elements forming interface between bone hole and implant or fastener, e.g. screw · CPC title