Abstract: A posterior fixation system for the human spine associated with fusion or corrective procedures in achieving proper alignment of the spine with regard to the patient's natural or corrective posture through optional postoperative re-adjustment. The fixation system may include a clamping block secured to a bone segment by pedicle screws or other anchoring device whereby a cross member passes through the multi-axial clamping block and is attached to a bone segment opposite the bridged section. The cross member is clamped and locked into position by engaging the set screw which is also accessible postoperatively by non-invasive means. The fixation of the bone segments promotes healing over an affected area while facilitating a proper alignment of the spine.