Method: visual analysis, material analysis, device history review, complaint history review, risk assessment.Result: the rod was returned in 2 pieces with the hex end fractured from the rest of the rod.The device was sent for material analysis.The elemental constituent was consistent with the material listed on the print.Material analysis of the device confirmed fatigue fracture at the contact point with the polyaxial screw.No material or manufacturing defects were found.Manufacturing records were reviewed for the corresponding lot and no relevant issues were identified.Conclusion: the most likely root cause is fatigue fracture of the rod due to length of implantation.As non fusion, patient activity level, and patient fall are unknown, these can also be contributing factors to the rod fracture.
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