Updated b5 to reflect tulip disengagement instead of "broke".Visual inspection confirmed that the tulip head is disengaged from screw shank.The locking ring on tulip head is deformed, and the shank bulb head has a deep deformation on one side of the bulb head.Device history records and complaint history records were reviewed for the corresponding lot number, and no relevant issues or complaints were identified.Complaint history records was also reviewed for the corresponding catalog number, and no similar complaints were identified.From the xia surgical technique guide: the blocker is assembled onto the universal tightener for insertion.The universal tightener is available in three different options; standard, short, and double-ended.Note: the xia 3 universal tightener is not to be used for final tightening.The torque wrench indicates the optimal torque force that must be applied to the implant for final tightening.Line up the two arrows to achieve the final tightening torque of 12nm.Note: do not exceed 12nm during final tightening.The anti-torque key must be used for final tightening.The amount of deformation observed on the returned device indicates excessive torque over 12nm was applied during set screw insertion.Location of shank bulb deformation and locking ring deformation indicates screw being angulated which may have increased the stress on the tulip head.The most likely cause of the reported event was determined to be excessive force and/or torque applied during initial tightening.
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