Patent ID: 9439681
Filing Date: 2016-09-13
CPC Classification: A61B

Claim Text:
1. A method for securing a rod to a bone fixation assembly, the method comprising the steps of: inserting a head of a bone anchor into a collet; after the inserting step, implanting the bone anchor into a vertebral body so that a threaded shaft of the bone anchor is engaged with the vertebral body and the collet is spaced away from the vertebral body; positioning the collet in a bore of a body in a loading position such that the collet is in an enlarged diameter portion of the bore, wherein when the collet is in the loading position, the collet is polyaxially rotatable relative to the bone anchor; and causing the collet to move along a direction from the loading position to a locking position such that the collet is in contact with a spherical undercut of the body that: 1) is in the bore, 2) extends in the direction such that the spherical undercut defines a length measured along the direction, and 3) is spaced from the enlarged diameter portion, wherein when the collet is in the locking position the collet is fixed to the bone anchor with respect to relative polyaxial rotation.