A tulip-shaped rod-receiving member in a spinal rod system is provided with a transverse slot accessible from the top of the tulip member for placing the rod therein until the rod seats. A locking assembly includes a cap having inclined surfaces that cooperate with inclined surfaces on the rod-receiving member to lock and bias inwardly the rod-receiving member relative to the cap. A novel seating ring is provided for the bone screw to be supported in the tulip in a manner that maximizes support and optimizes axial alignment of forces.
