This report is being resubmitted for an incident that occurred earlier.Evaluation of the returned devices found the clamps and saddle of the screw head attached to the screw.Wearing of the anodized coating can be seen on the amp saddle and a cylindrical impression can be seen across the high points of the saddle, perpendicular to the saddle's rod slot.The screw head, looking cap, and curved rod were returned still assembled.The screw head was missing the saddle and clamps which were attached to the screw.The curved rod was fully seated in the screw head's rod slot with no space between the rod and screw head.The locking cap was in full contact with the curved rod and the top of the locking cap was countersunk below the top surface of the screw head.The observed damage to the screw head is indicativeof abnormal or excessive force.The cylindrical impression on the saddle indicates that the saddle may have been rotated out of position as the marks were perpendicular to the rod slot.This could have resulted in excessive compression and translation of the internal components.Additionally, excessive loading.Of the implants post-operatively may have contributed to the reported issue.However, the exact cause cannot be determined.
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