US 12,433,645 B2
Coupling assembly for coupling a rod to a bone anchoring element, and polyaxial bone anchoring device
Lutz Biedermann, VS-Villingen (DE); and Bernd Fischer, Bräunlingen (DE)
Assigned to BIEDERMANN TECHNOLOGIES GMBH & CO. KG, Donaueschingen (DE)
Filed by BIEDERMANN TECHNOLOGIES GMBH & CO. KG, Donaueschingen (DE)
Filed on May 16, 2025, as Appl. No. 19/210,212.
Application 19/210,212 is a continuation of application No. 18/439,562, filed on Feb. 12, 2024, granted, now 12,324,608.
Application 18/439,562 is a continuation of application No. 17/376,900, filed on Jul. 15, 2021, granted, now 11,925,391, issued on Mar. 12, 2024.
Application 17/376,900 is a continuation of application No. 16/989,366, filed on Aug. 10, 2020, granted, now 11,090,090, issued on Aug. 17, 2021.
Application 16/989,366 is a continuation of application No. 15/900,204, filed on Feb. 20, 2018, granted, now 10,779,862, issued on Sep. 22, 2020.
Application 15/900,204 is a continuation of application No. 14/596,169, filed on Jan. 13, 2015, granted, now 9,924,971, issued on Mar. 27, 2018.
Claims priority of application No. 14151009 (EP), filed on Jan. 13, 2014.
Prior Publication US 2025/0275788 A1, Sep. 4, 2025
Int. Cl. A61B 17/70 (2006.01); A61B 17/86 (2006.01); A61B 17/88 (2006.01)
CPC A61B 17/7037 (2013.01) [A61B 17/7032 (2013.01); A61B 17/8615 (2013.01); A61B 17/8888 (2013.01)] 20 Claims
OG exemplary drawing
 
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, and an accommodation space at the second end for accommodating the head of the bone anchoring element;
a retainer element positionable at least partially in the accommodation space, the retainer element comprising an upwardly facing surface configured to contact and exert an upwardly directed pressure on the head; and
a spring separate from the retainer element, the spring comprising a lower surface configured to contact and exert a downwardly directed pressure on the retainer element;
wherein when the head, the retainer element, and the spring are held in the receiving part with the head in contact with the upwardly facing surface of the retainer element, the retainer element is configured to remain spaced apart from all portions of the head above a greatest diameter of the head measured in a direction perpendicular to the central axis, and the spring is configured to be blocked from contacting the head by another part of the bone anchoring device.