Patent ID: 7594924
Filing Date: 2009-09-29
Classification: A61B

Abstract:
1. A stabilization system for implantation in a patient, comprising: a bone anchor including a head and a shaft, the shaft extending away from the head along a bone insertion axis and being operable for connection to a bone of the patient; and a tulip including: (i) a first pivot element including a first body having at least one first wall member through which at least one first aperture extends, a first anchor engagement element of the first body including an outer surface and an inner surface, the inner surface including a contour operable to engage the head of the bone anchor and terminating at a first edge, and a first lever arm extending from the first body and forming at least a portion of a first locking element; and (ii) a second pivot element including a second body having at least one second wall member through which at least one second aperture extends, a second anchor engagement element of the second body including an outer surface and an inner surface, the inner surface including a contour operable to engage the head of the bone anchor and terminating at a second edge, and a second lever arm extending from the second body and forming at least a portion of a second locking element, wherein: the first and second wall members are disposed adjacent to one another such that the first and second apertures are sized, shaped and disposed in substantial axial alignment, and such that they are operable to receive a stabilization rod therethrough, and displacement of the first and second lever arms of the respective first and second locking elements away from one another: (i) urges the first and second wall members to pivot about a central portion of the first and second apertures, (ii) urges the first and second apertures to misalign and thereby clamp the stabilization rod, and (iii) causes the first pivot element and the second pivot element to pivot in opposite directions about the stabilization rod thereby creating a corresponding movement of the first and second anchor engagement elements toward one another such that the respective inner surfaces of the first and second anchor engagement elements are directed toward one another to engage opposite sides of the head of the bone anchor, thereby clamping the head of the bone anchor therebetween.