Patent ID: 8394108

Claim:
A screw driver for driving a multi-axial bone screw into a vertebra of a spine, the bone screw including an elongate shaft having a threaded screw portion at the distal end and a screw head at the proximal end, and a yoke articulatingly attached to the screw head, the yoke having a slot therethrough for receiving a connecting rod and including a lower surface, the yoke having an opening communicating with the screw head, said screw driver comprising: an elongate inner shaft having a distal end and a proximal end, said inner shaft defining a driving tip at said distal end configured to engage the screw head for rotation thereof; an outer retention sleeve disposed about said inner shaft and having a distal end and a proximal end, the inner shaft being freely rotatable within said outer retention sleeve and including said tip at the distal end thereof, the distal end of said outer retention sleeve configured to releasably engage the yoke for joint rotational movement therewith; and a stop rotatably mounted on said inner shaft between the distal end of the outer retention sleeve and the driving tip at the distal end of said inner shaft, said stop being sized to seat within the slot of said yoke and configured to rotate with rotation of said yoke; wherein rotation of said inner shaft rotates the elongate shaft of said bone screw relative to the said outer retention sleeve, said stop and said yoke which are joined in common.