The rod was received for visual and functional testing.Visual inspection revealed that the rod was partially distracted.X-ray imaging confirmed the reported issue.The end cap had disengaged.Functional testing was unable to be performed due to the condition of the nail.A device history review (dhr) was performed on lot number 8122610aaa and there were no deviations in the manufacturing process and the finished product met all acceptance criteria prior to shipment.Fsca investigation was performed and variation in the torque applied to the threaded cap during the assembly process was identified as the root cause of the failure.Per the manufacturing instructions, the threaded cap must be tightened to 40 in-lbs.Although all operators followed the assembly procedure, and the torque wrench indicated 40 in-lbs was applied, the manner of using the torque wrench resulted in variances in applied torque.The manner in which the operator handles the torque wrench may impact the actual torque applied to the end cap, thereby creating a false positive that the specified torque has been applied.If the specified torque is not applied, the effectiveness of the cap tightening process may be compromised.
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