Results of investigation: the devices, used in treatment, was returned for evaluation.The devices were manufactured in 2015 and 2016.A review of the device history records for the listed batches did not reveal any deviation from the standard manufacturing processes.At this time, we have no reason to suspect that the product failed to meet any product specifications at the time of manufacture.A review of the complaint history for the listed parts revealed no prior complaints for the listed failure mode with the same batch number.A review of the risk management file and instructions for use document for this failure mode was conducted and concluded this failure mode has been identified.The quality lab concluded that the plate experienced a high-energy ductile fracture.This fracture may have been caused by scratching the plate during implanting the device.The screws fractured by the initiation and subsequent propagation of fatigue cracking.The fatigue cracking eventually propagated to an extent that the remaining crosssectional area of the screws could not bear the imposed patient loading, which lead to an overload fracture.If one of the screws fractured, the remaining screws would have been subjected to higher stresses causing them to suffer fatigue fractures as well.The fracture origin could not be located using sem.Fatigue cracking is caused by the screws bearing cyclic stresses in excess of the material endurance limit for an extended period of time.These stresses may be caused by any number of conditions, including but not limited to excessive patient activity levels prior to full bone union, applications of loads in excess of the material¿s strength, and/or poor bone quality.Our clinical/medical team noted: the photo provided shows the plate that was cut shorter prior to implantation and the broken screws.Four unlabeled, undated x-ray confirms the broken screws but does not indicate a definite reason for break.The contours of the original femoral neck fracture cannot be appreciated so non-union cannot be ruled out but revision documentation was not provided to confirm.It cannot be ruled out that the shortening of the plate and the resulting change in load on the plate contributed the broken screws.Based on the product evaluation, the conquest fn screws fractured by the initiation and subsequent propagation of fatigue cracking also the plate experienced a high-energy ductile fracture was from trimming prior to the implant as demonstrated in the x-ray.Without the revision report or medical history, the root cause of the origin of the implant fracture and pain cannot be concluded.We cannot rule out excessive patient activity prior to full bone union, change in the plate size and load handling capabilities, applications of loads in excess of the material¿s strength, and/or poor bone quality as contributing factors.Since this issue was resolved by conversion to a total hip, the impact to the patient was the revision and expected pain in the post ¿operative period.Should any relevant clinical information be provided, this complaint would be re-evaluated.No further clinical/medical assessment is warranted at this time.Based on this investigation, the need for corrective action is not indicated.Should additional information be received, the complaint will be reopened.We consider this investigation closed.
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