It was reported the patient had a revision surgery due to femur subtrochanteric atrophic non-union with hardware fatigue.The associated trigen trochanteric nail along with damaged recon screws and a fraction of cable were returned for evaluation.A lab analysis conducted during this investigation noted that the nail fractured by the initiation and subsequent propagation of fatigue cracking.The fracture most likely initiated on the lateral side of the nail.The fatigue cracking eventually propagated to an extent that the remaining cross sectional area of the nail could not bear the imposed patient loading which led to an overload fracture.Fatigue cracking is caused by the nail 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 prior to full bone union, applications of loads in excess of the material¿s strength, and/or poor bone quality.Sem examination showed beach marks on the nail fracture surface and striations on the compression screw surface.A clinical analysis noted that a hematoma is a risk factor from surgeries or any sort of invasive medical procedures as they damage nearby tissues and blood vessels, often hematomas may form around the site of the procedure.The review of the manufacturing records for the listed batches did not reveal any deviation from the standard manufacturing processes.A review of the complaint history for the listed parts revealed no prior complaints for the listed failure mode with the same batch number.At this time, we have no reason to suspect that the product failed to meet any product specifications at the time of manufacture.A relationship, if any, between the devices and the stated issue could not be corroborated.No further investigation is warranted for this complaint; smith and nephew will continue to monitor for future complaints and investigate as necessary.
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The associated complaint device was not returned.A clinical analysis indicated that it is known that a hematoma is a risk factor from surgeries or any sort of invasive medical procedures.Because these procedures damage nearby tissues and blood vessels, often hematomas may form around the site of the procedure.There is no evidence that our device contributed to the development of the hematoma.No details regarding the patient¿s weight-bearing status were provided.Additionally without x-ray images to confirm the fracture was adequately reduced or the return of the explant for analysis we are unable to conclude the root cause of the broken nail and nonunion though the nonunion could have resulted in fatigue stress to the nail.Although the surgery time was extended for this patient it was reported that the patient tolerated the procedure well.The impact to the patient beyond the revision cannot be determined.Without the actual product involved our investigation cannot proceed.No further investigation is warranted for this complaint; however we will continue to monitor for future complaints and investigate further as necessary.If the devices are received in the future, this complaint can be re-opened.We consider this complaint closed.
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