Patent ID: 11937850
Assignee: BIEDERMANN TECHNOLOGIES GMBH & CO. KG
Field: Medical technology (Instruments)
Classification: CPC A | IPC A

Claim 14:
15. A bone anchoring device comprising:
a receiving part for coupling a rod to a bone anchoring element, the receiving part having a first end, a second end, and a central axis extending between the first end and the second end, the receiving part comprising:
two legs defining a recess at the first end for receiving the rod; and
a head receiving portion at the second end that is at least partially expandable and having an opening at the second end for inserting and pivotably holding a head of the bone anchoring element therein; and

a locking ring that is mountable around the head receiving portion in an axial direction to a first axial position while the locking ring remains at a first rotational orientation relative to the receiving part, and that is further configured to be held at the first axial position while the locking ring remains at the first rotational orientation and while the locking ring remains substantially free from any forces from outside the bone anchoring device acting thereupon;
wherein a protrusion extends radially away from at least one of an outer surface of the head receiving portion or an inner surface of the locking ring as the surface extends circumferentially, such that when the locking ring is around the head receiving portion, the locking ring is rotatable around the central axis from a first rotational orientation to a second rotational orientation where the protrusion is engaged to increase a compressive force exerted by the locking ring on the head receiving portion compared to the first rotational orientation; and
wherein each of the legs comprises a weakened portion that permits breaking away of part of the legs to shorten a height of the receiving part, and the legs comprise an internal thread for engaging a fixation element, the internal thread extending into the part of the legs configured to be broken away.