CPC A61B 17/7035 (2013.01) [A61B 17/70 (2013.01); A61B 17/7001 (2013.01); A61B 17/7032 (2013.01); A61B 17/7037 (2013.01); A61B 2017/00526 (2013.01); A61B 17/68 (2013.01)] | 18 Claims |
1. A polyaxial bone anchor comprising:
a housing having an upper end, a lower end and a bore extending through the housing from the upper end to the lower end, the bore opening out at the lower end at a lower opening, the housing including a channel configured for receiving an elongate stabilization member therethrough which extends from a first side surface of the housing to a second side surface of the housing opposite the first side surface transverse to the bore;
a retainer positioned into the bore of the housing and having an outermost diameter greater than a diameter of the lower opening, the retainer including:
a lower portion having a plurality of alternating tabs and slots circumferentially arranged to define a cavity therein;
an upper portion extending into the channel of the housing configured to support the elongate stabilization member off a bottom of the channel; and
an intermediate portion residing between the lower portion and the upper portion, wherein the intermediate portion includes a resilient spring that enables the intermediate portion to be compressed between the upper portion and the lower portion; and
a bone screw including a head portion and a shank extending from the head portion, the head portion of the bone screw positionable in the cavity of the retainer with the shank extending from the lower end of the housing by deflecting the tabs radially outward to enlarge a lower opening of the retainer into the cavity from a diameter less than a diameter of the head portion to a diameter greater than or equal to the diameter of the head portion.
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