RECEIVING PART FOR RECEIVING A ROD FOR COUPLING THE ROD TO A BONE ANCHORING ELEMENT, BONE ANCHORING DEVICE, METHOD AND TOOL FOR ASSEMBLING THE SAME

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 with a first end and a second end, a rod receiving portion with a channel for receiving a rod, and a head receiving portion for accommodating a head of a bone anchoring element, the head receiving portion having an open end at the second end of the receiving part body and being flexible so as to allow introduction and clamping of the head; and

a locking ring configured to be positioned around the head receiving portion,

wherein the locking ring can assume a first position with respect to the receiving part body in which the locking ring is latched to the receiving part body in a position where the head receiving portion is expandable to facilitate insertion of a head of a bone anchoring element, and

wherein the locking ring can assume a second position with respect to the receiving part body in which the locking ring is latched to the receiving part body in a position where the locking ring compresses the head receiving portion, such that when a bone anchoring element has a head inserted in the head receiving portion, the bone anchoring element is held adjustably at a first angular position relative to the receiving part.

2 . The receiving part of claim 1 , wherein when the locking ring is in the second position, the locking ring provides a first compression force on the head receiving portion such that when a head of a bone anchoring element is inserted in the head receiving portion, the head is not fully locked.

3 . The receiving part of claim 2 , wherein the locking ring can assume a third position with respect to the receiving part body in which the locking ring compresses the head receiving portion with a second compression force greater than the first compression force, such that when a head of a bone anchoring element is inserted in the head receiving portion, the head is fully locked in the head receiving portion.

4 . The receiving part of claim 1 , wherein in the first position, the locking ring is prevented from moving in an axial direction towards the first end of the receiving part body, but is movable towards the second end of the receiving part body by application of a force.

5 . The receiving part of claim 1 , wherein the locking ring has a first projection or a first recess which is configured to cooperate with a corresponding first recess or first projection of the receiving part body to latch the locking ring in the first position.

6 . The receiving part of claim 5 , wherein the receiving part body has an asymmetric recess.

7 . The receiving part of claim 1 , wherein in the second position, the locking ring is prevented from moving in an axial direction towards the first end of the receiving part body, but is movable towards the second end of the receiving part body by application of a force.

8 . The receiving part of claim 7 , wherein the receiving part body has an asymmetric recess.

9 . The receiving part of claim 1 , wherein when the locking ring is positioned around the receiving part body, the locking ring has a first annular portion which is non-resilient and which is arranged to be closer to the second end of the receiving part body and a second annular portion which is resilient and which is arranged to be closer to the first end of the receiving part body.

10 . The receiving part of claim 1 , wherein the head receiving portion has an exterior surface with a tapered or curved portion and the locking ring has an interior surface with a correspondingly tapered or curved portion which are configured to cooperate with one another, such that when a head of a bone anchoring element is inserted in the head receiving portion, the head is clamped when the locking ring is moved towards the second end.

11 . The receiving part of claim 10 , wherein the locking ring further comprises an inwardly projecting edge at one end which cooperates with the head receiving portion near the second end of the receiving part body to provide additional clamping.

12 . A bone anchoring device comprising:

a bone anchoring element comprising a shaft with a threaded portion and a head with a spherical outer surface portion; 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 with a first end and a second end, a rod receiving portion with a channel for receiving a rod, and a head receiving portion for accommodating the head of the bone anchoring element, the head receiving portion having an open end at the second end of the receiving part body and being flexible so as to allow introduction and clamping of the head; and

a locking ring configured to be positioned around the head receiving portion,

wherein the locking ring can assume a first position with respect to the receiving part body in which the locking ring is latched to the receiving part body in a position where the head receiving portion is expandable to facilitate insertion of the head, and

wherein the locking ring can assume a second position with respect to the receiving part body in which the locking ring is latched to the receiving part body in a position where the locking ring compresses the head receiving portion to compress the inserted head, such that the bone anchoring element is held adjustably at a first angular position relative to the receiving part.

13 . A method for assembling a bone anchoring device, the bone anchoring device comprising a bone anchoring element comprising a shaft for anchoring in 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 for accommodating the head of the bone anchoring element in a polyaxial manner, and a locking ring, in a first position with respect to the receiving part body in which the locking ring is latched to the receiving part body in a position in which the head of the bone anchoring element can be introduced into the receiving part body and can freely pivot therein, the method comprising:

inserting the head of the bone anchoring element into the receiving part body; and

moving the locking ring and the receiving part body relative to each other until the locking ring assumes a second position with respect to the receiving part body in which the locking ring is latched to the receiving part body in a position where the locking ring compresses a portion of the receiving part body to compress the head, such that the bone anchoring element is held adjustably at a first angular position relative to the receiving part.

14 . The method of claim 13 , wherein the shaft of the bone anchoring element comprises a threaded portion and the head of the bone anchoring element comprises a spherical outer surface portion,

wherein the receiving part body has a first end and a second end, a rod receiving portion with a channel for receiving a rod, and a head receiving portion for accommodating the head of the bone anchoring element, the head receiving portion having an open end at the second end of the receiving part body and being flexible so as to allow introduction and clamping of the head, and

wherein the locking ring is configured to be positioned around the head receiving portion.

15 . The method of claim 13 , wherein a same tool is utilized for both the inserting of the head and the moving of the locking ring and the receiving part body relative to each other.

16 . The method of claim 15 , wherein a first holder of the tool holds the bone anchoring element and a second holder of the tool holds the receiving part, and wherein the first holder and the second holder are moved closer relative to one another for both the inserting of the head and the moving of the locking ring and the receiving part body relative to each other.

17 . A tool for assembling a bone anchoring device, the bone anchoring device comprising a bone anchoring element with a head and a shaft to be anchored in a bone, 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 with a head receiving portion for accommodating the head of the bone anchoring element and a locking ring configured to be positioned around the head receiving portion, the tool comprising:

a first holder for holding a bone anchoring element; and

a second holder for holding a receiving part,

wherein the first and second holders are movable relative to one another, such that when the first holder is holding a bone anchoring element and the second holder is holding a receiving part, the movement between the first and second holders is configured to press the bone anchoring element against the receiving part body or the locking ring, and

wherein the tool further comprises an abutment device which is adjustable between a first configuration to provide a first abutment for preventing movement of the receiving part body with respect to the second holder when the first holder is moved towards the second holder to engage the bone anchoring element with the receiving part body, and a second configuration to provide a second abutment for preventing movement of the locking ring with respect to the second holder when the first holder is moved further towards the second holder, such that the bone anchoring element with the engaged receiving part body is moved relative to the locking ring to adjust the locking ring from the first position to the second position.

18 . The tool of claim 17 , wherein the second holder has a recess for inserting the receiving part body, and wherein the abutment device is configured to adjust the depth of the recess between a first depth for the second holder to provide the first abutment and a second depth for the second holder to provide the second abutment.

19 . A method for coupling a rod to a bone anchoring element via a receiving part, the bone anchoring element comprising a shaft and a head, and the receiving part comprising a receiving part body with a first end and a second end, a rod receiving portion with a channel for receiving a rod, and a head receiving portion for accommodating the head of the bone anchoring element, the head receiving portion having an open end at the second end of the receiving part body and being flexible so as to allow introduction and clamping of the head, and a locking ring around the head receiving portion in a first position with respect to the receiving part body in which the locking ring is latched to the receiving part body in a position where the head receiving portion is expandable and in which the head of the bone anchoring element can be introduced into the head receiving portion and can freely pivot therein, the method comprising:

inserting the bone anchoring element in a first holder of a tool, and inserting the receiving part in a second holder of the tool;

moving one of the first holder or the second holder towards the other one of the first holder or the second holder to insert the head of the bone anchoring element into the head receiving portion of the receiving part body;

adjusting the tool;

moving the one of the first holder or the second holder further towards the other one of the first holder or the second holder to move the locking ring and the receiving part body relative to each other until the locking ring assumes a second position with respect to the receiving part body in which the locking ring is latched to the receiving part body in a position where the locking ring compresses the head receiving portion to compress the head, such that the bone anchoring element is held adjustably at a first angular position relative to the receiving part; and

removing the attached bone anchoring element and receiving part from the tool.

20 . The method of claim 19 , further comprising:

inserting the shaft of the bone anchoring element into a bone;

applying a force on the receiving part to move the bone anchoring element to a second angular position relative to the receiving part, wherein in the second angular position the receiving part is aligned with a rod;

inserting the rod into the channel of the receiving part body; and

locking the rod in the receiving part and locking the receiving part at the second angular position relative to the bone anchoring element.

21 . The method of claim 20 , further comprising:

attaching at least one additional bone anchoring element and receiving part assembly to the same bone or a different bone;

aligning the receiving part of the at least one additional assembly with the rod; and

locking the rod in the receiving part and locking an angular position of the receiving part relative to the bone anchoring element for each of the at least one additional assembly.

22 . A tool for assembling a bone anchoring device, the bone anchoring device comprising a bone anchoring element with a head and a shaft to be anchored in a bone, 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 with a head receiving portion for accommodating the head of the bone anchoring element and a locking ring configured to be positioned around the head receiving portion, the tool comprising:

a first holder for holding a bone anchoring element; and

a second holder for holding a receiving part,

wherein the first and second holders are movable relative to one another, and

wherein at least one of the first holder or the second holder has a first abutment, a second abutment, and a recess, and wherein the first abutment is movable to adjust a depth of the recess independent from the movement between the first holder and the second holder.

23 . The tool of claim 22 , wherein the recess is on the second holder and is for inserting a receiving part body, and wherein the first abutment is configured to adjust the depth of the recess.

24 . The tool of claim 23 , wherein the second holder comprises an insert, the first abutment is defined by a wall of the insert, and the insert has a hole adjacent to the first abutment, and wherein the insert is movable between a first position where the first abutment is aligned with the recess and a second position where the hole is aligned with the recess.

25 . The tool of claim 23 , wherein the tool further comprises an insert for receiving the bone anchoring element, the insert configured to be inserted into the first holder.

26 . The tool of claim 25 , wherein the first holder has a recess configured to receive the insert.

27 . The tool of claim 25 , wherein the insert has at least two recesses.

28 . The tool of claim 27 , wherein the recesses on the insert are cylinder-shaped or U-shaped.

29 . The tool of claim 27 , wherein the recesses on the insert extend over the whole length of the insert.

30 . The tool of claim 25 , wherein the insert is rotatable while in the first holder.

31 . The tool of claim 22 , further comprising a handle and lever, wherein the first holder or the second holder is connected to the handle and lever and is configured to be moved towards the other one of the first holder or the second holder by actuation of the handle and lever.

32 . The tool of claim 31 , further comprising a frame, wherein a position of the other one of the first holder or the second holder is fixed with respect to the frame.

33 . A receiving part for receiving a rod for coupling the rod to a bone anchoring element, the receiving part comprising:

a receiving part body with a first end and a second end, a rod receiving portion with a channel for receiving a rod, and a head receiving portion for accommodating a head of a bone anchoring element, the head receiving portion having an open end at the second end of the receiving part body and being flexible so as to allow introduction and clamping of the head; and

a locking ring configured to be positioned around the head receiving portion,

wherein the locking ring can assume a first position with respect to the receiving part body in which the locking ring is latched to the receiving part body in a position where the head receiving portion is expandable,

wherein the locking ring can assume a second position with respect to the receiving part body in which the locking ring is latched to the receiving part body in a position where the locking ring compresses the head receiving portion inwardly towards a central axis of the receiving part body, and

wherein the locking ring can assume a third position with respect to the receiving part body where the locking ring compresses the head receiving portion inwardly closer towards the central axis of the receiving part body than when the locking ring is in the second position.