Receiving part for receiving a rod for coupling the rod to a bone anchoring element and a bone anchoring device with such a receiving part

Patent metadata

Field	Value
Publication number	US-9364266-B2
Application number	US-201313905062-A
Country	US
Kind code	B2
Filing date	May 29, 2013
Priority date	May 29, 2012
Publication date	Jun 14, 2016
Grant date	Jun 14, 2016

Abstract

A receiving part for coupling a rod to a bone anchoring element includes a receiving part body having a first end, a second end, a channel for receiving a rod, an accommodation space for accommodating a head of a bone anchoring element, and an opening at the second end for inserting the head, and a pressure element configured to be positioned at least partly in the accommodation space, the pressure element having a first end, a second end, a central axis, and a flexible portion to clamp an inserted head. The flexible portion has a first slit spaced apart from the second end of the pressure element that extends at least partially around the central axis, and a second slit that extends from the second end of the pressure element into the first slit. The first slit extends away from the second slit and is longer than the second slit.

First claim

What is claimed is:

1. A receiving part for receiving a rod for coupling the rod to a bone anchoring element, the receiving part comprising:
a receiving part body having a first end, a second end, a length that extends between the first end and the second end, a channel for receiving the rod, and an accommodation space for accommodating a head of the bone anchoring element, the accommodation space having an opening at the second end for inserting the head; and
a pressure element configured to be positioned at least partly in the accommodation space, the pressure element having a first end, a second end configured to be positioned closer than the first end of the pressure element to the second end of the receiving part body, a central axis extending through the first and second ends of the pressure element, and a flexible portion to clamp the inserted head of the bone anchoring element, wherein the pressure element has a length that is shorter than the length of the receiving part body;
wherein the flexible portion has a first slit spaced apart from the second end of the pressure element that extends at least partially around the central axis, and a second slit that extends from the second end of the pressure element into the first slit, and wherein the first slit extends away from the second slit and is longer than the second slit.

2. The receiving part of claim 1 , wherein the first slit and the second slit define a slit ring.

3. The receiving part of claim 2 , wherein the slit ring is configured to laterally encompass the inserted head of the bone anchoring element, and is connected to other portions of the pressure element in a monolithic manner via at least one connecting strip.

4. The receiving part of claim 2 , wherein the slit ring has a tapered exterior surface portion that tapers towards the second end of the pressure element.

5. The receiving part of claim 1 , wherein the second slit extends in a direction substantially parallel to the central axis.

6. The receiving part of claim 1 , wherein the first slit extends circumferentially in a direction substantially perpendicular to the central axis.

7. The receiving part of claim 1 , wherein only a single first slit and only a single second slit are provided on the pressure element.

8. The receiving part of claim 1 , wherein two first slits and two second slits are provided on the pressure element.

9. The receiving part of claim 1 , wherein the second slit is arranged at one end of the first slit in a circumferential direction.

10. The receiving part of claim 1 , wherein the flexible portion has a hollow spherical-segment shaped inner surface portion configured to accommodate the head of the bone anchoring element.

11. The receiving part of claim 1 , wherein the first end of the pressure element has a substantially cylindrical portion with a recess that is configured to accommodate the rod.

12. The receiving part of claim 1 , further comprising a stop configured to prevent movement of the pressure element towards the first end of the receiving part body when the pressure element is in the receiving part body.

13. The receiving part of claim 1 , wherein the pressure element can assume an insertion position in the receiving part body wherein the flexible portion is laterally expandable in the accommodation space, so as to allow introduction of the head of the bone anchoring element through the opening at the second end of the receiving part body into the pressure element.

14. The receiving part of claim 1 , wherein the accommodation space is substantially cylindrical, and has a tapered or curved narrowing portion near the second end of the pressure element.

15. The receiving part of claim 14 , wherein an outer wall of the pressure element has a tapered or rounded narrowing portion configured to cooperate with the narrowing portion of the accommodation space.

16. A bone anchoring device comprising:
a bone anchoring element having a shaft for anchoring to a bone and a head; and
a receiving part for receiving a rod for coupling the rod to the bone anchoring element, the receiving part comprising:
a receiving part body having a first end, a second end, a length that extends between the first end and the second end, a channel for receiving the rod, and an accommodation space for accommodating the head, the accommodation space having an opening at the second end for inserting the head; and
a pressure element configured to be positioned at least partly in the accommodation space, the pressure element having a first end, a second end configured to be positioned closer than the first end of the pressure element to the second end of the receiving part body, a central axis extending through the first and second ends of the pressure element, and a flexible portion to clamp the head, wherein the pressure element has a length that is shorter than the length of the receiving part body;
wherein the flexible portion has a first slit spaced apart from the second end of the pressure element that extends at least partially around the central axis, and a second slit that extends from the second end of the pressure element into the first slit, and wherein the first slit extends away from the second slit and is longer than the second slit.

17. The bone anchoring device of claim 16 , wherein the head has a spherical-segment shaped outer surface portion.

18. The bone anchoring device of claim 16 , wherein the flexible portion is sized relative to the head, such that the head is clamped by friction when the head is held in the flexible portion.

19. The bone anchoring device of claim 16 , further comprising a closure element for securing the rod in the receiving part body.

20. The bone anchoring device of claim 16 , wherein when the head is inserted in the receiving part body and the flexible portion of the pressure element is spaced apart from an inner wall of the receiving part body, the bone anchoring device can assume a position wherein the head is prevented from removal from the receiving part body.

21. A method for coupling a rod to a bone via a bone anchoring device, the bone anchoring device comprising a bone anchoring element having a shaft for anchoring to a bone and a head, a receiving part comprising a receiving part body having a first end, a second end, a length that extends between the first end and the second end, a channel for receiving the rod, and an accommodation space for accommodating the head, the accommodation space having an opening at the second end for inserting the head, and a pressure element configured to be positioned at least partly in the accommodation space, the pressure element having a first end, a second end configured to be positioned closer than the first end of the pressure element to the second end of the receiving part body, a central axis extending through the first and second ends of the pressure element, and a flexible portion to clamp the head, wherein the pressure element has a length that is shorter than the length of the receiving part body, and wherein the flexible portion has a first slit spaced apart from the second end of the pressure element that extends at least partially around the central axis, and a second slit that extends from the second end of the pressure element into the first slit, and wherein the first slit extends away from the second slit and is longer than the second slit, the method comprising:
inserting the bone anchoring element into a bone;
adjusting an angular position of the bone anchoring element relati

Assignees

• Biedermann Technologies Gmbh

Inventors

• Biedermann Lutz
• Biedermann Timo
• Dannecker Berthold
• Matthis Wilfried

Classifications

• A61B17/7037 Primary

  wherein pivoting is blocked when the rod is clamped · CPC title

• A61B17/7034

  characterised by a lateral opening · CPC title

• A61B17/7049 Primary

  Connectors, not bearing on the vertebrae, for linking longitudinal elements together (A61B17/7055, A61B17/7053, A61B17/7019 take precedence) · CPC title

• A61B17/685

  Elements to be fitted on the end of screws or wires, e.g. protective caps · CPC title

• A61F2002/30495

  using a locking ring · CPC title