SAGITTAL ANGLE SCREW WITH INTEGRAL SHANK AND RECEIVER

摘要

A spinal bone screw has a receiver with upstanding arms forming a channel for receiving a longitudinal connecting member, such as a rod, the receiver being integral with a threaded shank. The receiver further includes inner surfaces in sliding engagement with an insert, the insert having a seating surface for the rod. The insert and rod being pivotable with respect to the bone screw in a single plane.

主权项

1. In a spinal implant with a bone screw having a shank for implanting into bone, the bone screw capturing a longitudinal connecting member at an adjustable angle with respect to the shank, the improvement comprising:
a) a receiver having a pair of spaced upstanding arms forming a channel for receiving the longitudinal connecting member, the receiver being integral with the shank, the receiver forming a cavity communicating with the channel, the cavity partially defined by a curved seating surface having a first radius, the receiver further having an arcuate pivot track formed in an inner surface of one of the upstanding arms, the pivot track being spaced from the seating surface, the pivot track having a second radius, the second radius originating at a pivot axis disposed perpendicular to and intersecting with a central axis of rotation of the shank; and b) an insert having a bottom curved surface sized and shaped for slidable engagement with the receiver seating surface, a projection in slidable engagement with the pivot track and a top surface sized and shaped for closely receiving the longitudinal connecting member.