Patent ID: 11925391
Assignee: BIEDERMANN TECHNOLOGIES GMBH & CO. KG
Field: Medical technology (Instruments)
Classification: CPC A | IPC A

Claim 0:
1. A bone anchoring device for coupling a rod to a bone, the bone anchoring device comprising:
a bone anchoring element comprising a shank for anchoring to the bone and a head;
a receiving part having a first end, a second end below the first end, a central axis extending through the first end and the second end, a recess at the first end for receiving the rod, an accommodation space for accommodating the head of the bone anchoring element, and an opening at the second end to facilitate insertion of the head into the accommodation space;
a retainer element positionable at least partially in the accommodation space, wherein the retainer element comprises an upwardly facing surface configured to contact and to exert an upwardly directed pressure on the head; and
a pressure element positionable at least partially in the accommodation space and separable from the retainer element, wherein the pressure element comprises a downwardly facing surface configured to contact and to exert a downwardly directed pressure on the head for locking the head in the receiving part;
wherein when the retainer element and the pressure element are in the receiving part and the head of the bone anchoring element is outside of the receiving part, the pressure element is urged against another portion of the bone anchoring device; and
wherein when the head is inserted through the opening into the accommodation space, the head is movable axially above the upwardly facing surface of the retainer element, and a spring that extends circumferentially at least partially around the central axis is configured to urge the retainer element axially downwardly to prevent removal of the head back out of the opening.