US 11,925,399 B2
Self-holding screw head
Nils Zander, Eckernförde (DE); and Manfred Wieland, Kiel (DE)
Assigned to Stryker European Operations Holdings LLC, Kalamazoo, MI (US)
Filed by Stryker European Operations Holdings LLC, Kalamazoo, MI (US)
Filed on Jun. 28, 2022, as Appl. No. 17/851,311.
Application 17/851,311 is a continuation of application No. 16/518,110, filed on Jul. 22, 2019, granted, now 11,432,861.
Application 16/518,110 is a continuation of application No. 15/399,233, filed on Jan. 5, 2017, granted, now 10,426,535, issued on Oct. 1, 2019.
Prior Publication US 2022/0323129 A1, Oct. 13, 2022
Int. Cl. A61B 17/86 (2006.01); A61B 17/88 (2006.01)
CPC A61B 17/862 (2013.01) [A61B 17/8891 (2013.01); A61B 17/8615 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A bone fastener comprising:
a threaded shaft extending from a leading end to a trailing end, the threaded shaft having a central longitudinal axis therethrough; and
a head extending from the trailing end of the threaded shaft, the head having a threaded surface including a helical root,
wherein the helical root continuously becomes closer to the central longitudinal axis moving away from the threaded shaft to a free end of the head.