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

摘要

A receiving part for receiving a rod for coupling the rod to a bone anchoring element includes 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. A method for assembling a bone anchoring device includes 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 the second position with respect to the receiving part body.