Set screw disassociated from polyaxial screw causing rod to disengage from polyaxial screw.Surgeon discovered at 6-week follow-up visit with patient.Surgeon stated he was certain that the dissociation occurred due to the rod not being fully seated, and the driver not being able to overcome the force of the 6.0mm cocr rod.Surgeon further stated that when he performed the revision surgery on the patient, he observed that the rod was not fully seated.Upon utilizing the reduction tower intended to assure the rod is fully seated into the pedicle screw, he observed that the rod did reduce further.He then final tightened the set screw using the toque limiting driver handle.Reduction tower instruments are provided to specifically provide additional mechanical advantage to aid surgeon in seating the rod into the bottom of the pedicle screw prior to final tightening of set screw.Surgical technique shows how to visually or via palpitation confirm that set screw is fully seated.Device not returned for evaluation.
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