Patent ID: 8496661

Claim:
A system for use in performing spinal surgery, the system comprising: at least two threaded caps; at least two screw assemblies, each screw assembly comprising: a cannulated and threaded screw, the screw having a lower end for threaded engagement in bone and an upper end configured to be engaged by a driving tool; a polyaxial head permanently fixed to the screw upper end in a ball-and-socket engagement, the polyaxial head having a receiving area for engaging a rod, the polyaxial head having a threaded area for receiving one of the caps after the rod is engaged in the receiving area such that the rod is sandwiched by the polyaxial head and the cap; and an extension portion fixed to the polyaxial head wherein movement of the extension portion causes the polyaxial head to move in concert, the extension portion having first and second arms spaced apart from one another such that the first and second arms are on opposite sides of the polyaxial head receiving area, the extension portion having at least one point of weakness such that forcing the first and second arms away from one another causes the extension portion to divide at the point of weakness and separate the extension portion from the polyaxial head; wherein the ball-and-socket engagement allows 360 degree rotation of the polyaxial head about a center axis of the screw and additionally allows the polyaxial head to pivot relative to the screw; wherein the first and second arms of the extension portion are sized to extend through skin while the screw is engaged in bone; wherein: the first and second arms of the extension portion are configured to pass the rod therebetween while the rod extends in a first direction; wherein the polyaxial head is configured to engage the rod in the receiving area while the rod extends in a second direction; and wherein the first direction is generally perpendicular to the second direction; and a rod insertion tool, the rod insertion tool comprising: an elongated housing having upper and lower ends; a rotating end pivotably coupled to the housing lower end; a first user input device; linkage coupling the rotating end to the first user input device to allow at least about ninety degrees of rotation for the rotating end controlled by the first user input device; a deformable crown operatively coupled to the rotating end of the rod insertion tool, the deformable crown being biased toward a contracted configuration; an actuator movable between first and second positions, the second position being inwardly adjacent the deformable crown and causing the deformable crown to deform to an expanded configuration, the first position allowing the deformable crown to be at the contracted configuration; a second user input device; and structure coupling the second user input device to the actuator for allowing movement of the actuator between the first and second positions controlled by the second user input device.