Polyaxial bone anchoring device

Patent metadata

Field	Value
Publication number	US-12564427-B2
Application number	US-202418593680-A
Country	US
Kind code	B2
Filing date	Mar 1, 2024
Priority date	Dec 21, 2015
Publication date	Mar 3, 2026
Grant date	Mar 3, 2026

Abstract

A polyaxial bone anchoring device includes a bone anchoring element having a head, a receiving part having a channel for receiving a rod and an accommodation space for pivotably holding the head, and a pressure member having a pressure exerting surface and a deformable portion with a free end. The deformable portion is adjustable from a first configuration where a first part of the deformable portion is supported at a first axial position relative to the receiving part while a second part of the deformable portion protrudes further radially into the channel than parts of the deformable portion positioned axially above the second part, to a second configuration where the second part of the deformable portion is deformed radially outwardly and the pressure exerting surface is shifted lower axially to exert pressure on the head while the first part of the deformable portion remains supported at the first axial position.

First claim

What is claimed is:

1 . A polyaxial bone anchoring device comprising:
a receiving part having a first end, a second end below the first end, a longitudinal axis extending through the first end and the second end, a channel at the first end for receiving a rod, an engagement surface at the first end for engaging a locking member to lock the rod in the receiving part, and an accommodation space at the second end for pivotably holding the head; a pressure member positionable in the receiving part and comprising a pressure exerting surface configured to exert pressure on a head of a bone anchoring element to lock the head relative to the receiving part; and an expandable member having a first end directly engageable with the receiving part and an opposite second end directly engageable with the pressure member, wherein the expandable member is axially expandable in a direction of the longitudinal axis from a first configuration to a second configuration while a radial position of at least the first end of the expandable member relative to the longitudinal axis remains constant to urge the pressure member towards the second end of the receiving part to exert pressure on an inserted head; and wherein the entire expandable member is positioned lower axially than the entire engagement surface of the receiving part, and wherein the pressure member is prevented from extending to an axial position that is higher than the first end of the expandable member.

2 . The polyaxial bone anchoring device of claim 1 , wherein the expandable member comprises a deformable portion configured to deform at least partially in a direction transverse to the longitudinal axis.

3 . The polyaxial bone anchoring device of claim 1 , wherein the second end of the expandable member is fixedly connected to the pressure member.

4 . The polyaxial bone anchoring device of claim 1 , wherein the expandable member is directly accessible from the channel for the rod.

5 . The polyaxial bone anchoring device of claim 4 , wherein the expandable member extends at least partially into the channel for the rod.

6 . The polyaxial bone anchoring device of claim 1 , wherein the expandable member is adjustable from the second configuration back to the first configuration.

7 . The polyaxial bone anchoring device of claim 1 , wherein when the expandable member is adjusted to the second configuration, the expandable member is configured to remain at the second configuration absent any forces from outside the bone anchoring device.

8 . The polyaxial bone anchoring device of claim 1 , wherein the expandable member and the pressure member are separate parts and separable from one another.

9 . The polyaxial bone anchoring device of claim 1 , wherein the expandable member comprises two expandable members respectively located on either side of the channel for the rod.

10 . A polyaxial bone anchoring device comprising:
a bone anchoring element comprising a shank for anchoring to a bone and a head; a receiving part having a first end, a second end, a longitudinal axis extending through the first end and the second end, a channel at the first end, and an accommodation space for pivotably holding the head, the accommodation space forming an opening at the second end for inserting the head; a pressure member positionable in the receiving part and comprising a pressure exerting surface configured to exert pressure on the head to lock the head relative to the receiving part; a rod insertable into the channel; and an expandable member comprising an engagement surface configured to engage the rod; wherein when the pressure member and the expandable member are in the receiving part at an insertion position, the head is insertable through the opening at the second end into and configured to be held in the receiving part, and thereafter the pressure member and the expandable member are adjustable from the insertion position to a pre-locking position to restrict removal of the head through the opening; and wherein when the head, the pressure member, and the expandable member are in the receiving part at the pre-locking position, the rod is insertable into the channel and configured to directly engage the engagement surface of the expandable member to axially expand the expandable member in a direction of the longitudinal axis from a first configuration to a second configuration to urge the pressure member towards the second end of the receiving part to exert pressure on the head, and is configured to block adjustment of the expandable member back to the first configuration.

11 . The polyaxial bone anchoring device of claim 10 , wherein the expandable member comprises a deformable portion configured to deform at least partially in a direction transverse to the longitudinal axis.

12 . The polyaxial bone anchoring device of claim 11 , wherein the rod is configured to block the deformable portion from deforming in the direction transverse to the longitudinal axis.

13 . The polyaxial bone anchoring device of claim 10 , wherein the expandable member is fixedly connected to the pressure member.

14 . The polyaxial bone anchoring device of claim 10 , wherein the expandable member and the pressure member are separate parts and separable from one another.

15 . The polyaxial bone anchoring device of claim 10 , wherein the expandable member is adjustable from the second configuration back to the first configuration when the rod is spaced apart from the channel.

16 . The polyaxial bone anchoring device of claim 10 , wherein when the expandable member is at the second configuration, the pressure member exerts a force on the head to hold an angular position of the head relative to the receiving part.

17 . The polyaxial bone anchoring device of claim 10 , further comprising a compressible portion configured to hold the head in the receiving part and to exert a pressure directed towards the first end of the receiving part on the head.

18 . The polyaxial bone anchoring device of claim 17 , wherein the compressible portion is formed as part of the pressure member.

19 . A polyaxial bone anchoring device comprising:
a receiving part having a first end, a second end, a longitudinal axis extending through the first end and the second end, a channel at the first end for receiving a rod, and an accommodation space at the second end for pivotably holding the head; a pressure member positionable in the receiving part and comprising a pressure exerting surface configured to exert pressure on a head of a bone anchoring element to lock the head relative to the receiving part; and an expandable member having a first end fixedly connected to the receiving part in an unadjustable manner and an opposite second end configured to engage the pressure member, wherein the expandable member is axially expandable in a direction of the longitudinal axis from a first configuration to a second configuration to urge the pressure member towards the second end of the receiving part to exert pressure on an inserted head.

20 . The polyaxial bone anchoring device of claim 19 , wherein the expandable member is directly engageable with the pressure member.

Assignees

• Biedermann Technologies Gmbh

Inventors

• Biedermann Lutz
• Fischer Bernd

Classifications

• A61B2017/564

  Methods for bone or joint treatment · CPC title

• A61B2017/00867

  shape memory effect · CPC title

• A61B17/7032

  Screws or hooks with U-shaped head or back through which longitudinal rods pass · CPC title

• A61B17/7002

  Longitudinal elements, e.g. rods · CPC title

• A61B17/7035

  Screws or hooks, wherein a rod-clamping part and a bone-anchoring part can pivot relative to each other · CPC title