Patent ID: 8808335

Claim:
A locking element configured to be used with a polyaxial bone anchor, wherein the bone anchor comprises a head with a spherical exterior surface portion including a largest diameter the locking element being cylindrical with a bottom side facing a head of the bone anchor, a top side opposite to the bottom side, and a circumferential outer edge comprising a surface portion with an external thread; wherein, the locking element has a first recess at the bottom side for accommodating at least a portion of the head, and a second recess at the top side for engagement with a driver, the second recess being located outside the center of the top side, and wherein a first level (L 1 ) is defined by the highest point of a circle with the largest diameter drawn around the head, and a second level (L 2 ) is defined by the bottom of the second recess, (L 2 ) being at a level not higher than (L 1 ), and wherein the second recess comprises a plurality of pockets that are closed towards the outer edge of the locking element.