23. The spinal fixation system of claim 21 , 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.
23. The spinal fixation system of claim 21 , 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. 24. The spinal fixation system of claim 23 , wherein the subassembly is configured to securely fasten both the clamp to the bone anchor and the spinal rod to the clamp.