The reported event could be confirmed, although the device was not returned but an image was shared which confirms the alleged failure.A device inspection was not possible since the affected device was not returned, and no other evidences were provided for investigation.A review of the device history for the reported lot did not indicate any abnormalities.No indications of manufacturing or design related problems were found during the investigation.A review of the labeling did not indicate any abnormalities.A few x-rays were provided which were presented to our health care professional for evaluation, questions about confirmation of the non-union its likely reason for breakage of nail, to which medical expert replied: "the initial fracture was a (reverse) subtrochanteric fracture.These are very difficult to treat due to the intrinsic instability of the fracture.Since we only see one direction on the provided x-rays, i cannot judge the initial repositioning properly.Trying to get the best possible stability is key.In general, there is agreement of treating these fractures with a long nail to create additional intrinsic stability.It is unclear what the post-operative instructions were regarding weightbearing.By the way the patient characteristics and history do play a key role in these instructions.The weight bearing was allowed after 6wks? 2 months? directly? looking at the follow-up x-rays, it seems the second x-ray is showing at least delayed union, but maybe even a non-union since there seems to be no callus formation at all after 4 months.These fractures are known for their instability and most often of a lack of compression at the fracture site which causes movement at the fracture site.This movement will prevent the bone from healing and cause movement in the interface between the nail and the screw continuously.This movement results in friction/ fatigue/ breakage, etc.Looking at the event, it seems that the fracture did not heal at all after the initial surgery.The gamma-nail is not intended to weight bear for such a long time.If the fracture did not heal, the non-union can be cause of the breakage of the nail, since the nail is not intended to bear that weight/ or those forces at that time after surgery anymore (which is stated in warnings and cautions in the labelling of the product and the lifetime statement).¿ based on the available information and the opinion received from the health care professional, the root cause of the issue is most likely patient related.The available x-rays indicate towards a non-union which ultimately increased loading on the nail and consequently it broke over a period of close to 4 months.The ifu clearly specifies: ¿these devices can break when subjected to the increased loading associated with delayed unions and/or non-unions.Internal fixation devices are load sharing devices which are intended to hold fractured bone surfaces in apposition to facilitate healing.If healing is delayed or does not occur, the appliance may eventually break due to metal fatigue.Loads on the device produced by load bearing and the patient¿s activity level will dictate the longevity of the device.¿ if the device is returned or if any additional information is provided, the investigation will be reassessed.
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