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The reported event could be confirmed, since the nail was returned broken as complained.The device inspection revealed the following: the received nail is completely broken in the webs of the lag screw hole.The proximal portion of the broken nail exhibits clear signs of a fatigue fracture.A fatigue zone with a smooth surface and distinct progression lines is visible.On the distal portion, one side shows a highly polished and shiny surface, likely resulting from friction with the lag screw.This contact was probably caused by a shift in the lag screw following the initial nail fracture, leading to abnormal rubbing between the two components.Evidence of this friction is also visible on the lag screw itself, which was returned with significant wear marks.The opposite side of the proximal portion also reveals features consistent with fatigue fracture.Altogether, the fracture pattern is characteristic of a fatigue-related failure.The nail likely fractured progressively due to high tension and loading over time, before ultimately failing.In addition, this case and provided documentation were forwarding to medical affairs, with the following review: « it is a pseudo-arthrosis/non-union: failure to unite led to failure of the implant.Based on the provided information, the root cause of the reported event is multi-factorial: the location of the fracture and the technical aspects of the surgical procedure may have contributed to the event.Furthermore, patient activity levels post-op, co-morbidities may also have contributed to an inadequate load distribution, and therefore the breakage of the implant.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.Based on the investigation, the root cause was attributed to a combination of user and patient condition related issue.The implant breakage occurred as a direct result of the bone non-union.The choice of the construct and technical aspects of the procedure may also have contributed to the non-union, and therefore failure of the implant.If more information is provided, the case will be reassessed.
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