The reported event could be confirmed, since the plate is broken as complained.The device inspection revealed the following: the visual inspection has shown that the plate is broken apart on the fourth locking hole.The breakage of the plate can also be confirmed on the received x-rays.The microscopic examination of the fracture surface reveals the fracture to be a typical fatigue fracture evident by a smooth topography.The origin of the crack was at the upper right corner of the locking hole and there are progression lines in this area visible.The rest of the fracture face has the typical view of a fatigue fracture with an uniform fine-grained texture.The relevant dimensions were as far as possible checked and no deviation from the specification could be detected.A review of the device history for the reported lot did not indicate any abnormalities.No corrective actions are required at this time.A review of the labeling did not indicate any abnormalities.No indications of material, manufacturing or design related problems were found during the investigation.The complaint was forwarded to medical affairs for a medical opinion with following feedback: "no obvious technical failures can be seen.There are some patient related factors which assumingly have contributed to the failure of the plate.First of all the patients age.At that age the bone quality and the capability of restoration of bone is definitely reduced.Then we have ¿kissing¿ prostheses of the hip and (stem) of the knee joint.The ¿working range¿ of the bone is only a few centimeters.Instead of distributing the load on the whole plate - due to the stiff hip and knee joint stem - movement and thus energy transfer is only possible at the short bone area in between the prostheses.This is probably the most relevant factor, here.I would recommend to add a second plate at the medial circumference of the femur to exclude high loads on the plate.I fear that although additional measurements have been taken with the cerclage the outcome (breakage) may become the same." based on investigation, the root cause of the breakage was attributed to a patient related issue.Different patient related factors did result in fatigue failure of the plate.If more information is provided, the case will be reassessed.
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