3. The spinal fixation system of claim 1 , further comprising a subassembly configured to engage a portion of at least one of the first and second plates to move one of the first and second plates towards the other plate to clamp the spinal rod within the receiving portion.
1. A spinal fixation system, comprising: a bone anchor having a bone-engaging portion and a spinal fixation element receiving portion with opposed arms extending substantially parallel to a longitudinal axis that extends from a proximal end to a distal end of the bone anchor and configured to receive a spinal fixation element therebetween; a spinal rod having first and second ends; and a clamp that is matable to the spinal fixation element receiving portion of the bone anchor, the clamp having a first plate disposed above a second plate, the two plates each having an opening extending therethrough, and the two plates being connected by a receiving portion that is offset from the opening, the receiving portion being configured to receive the spinal rod therethrough; wherein the first and second plates are movable toward one another to clamp the spinal rod within the receiving portion.