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The reported event could be confirmed since the device was returned for evaluation and matches the alleged failure.The device inspection revealed the following: the received nail is completely broken in the webs of the proximal lag screw hole.In the microscopic view, progression lines like beach marks are clearly visible on both proximal and distal fragments which clearly indicates that it is a fatigue failure.Marks of mis-drilling also observed on the posterior web of the distal fragment which affects the load bearing capacity of the nail.Also, the load bearing point denoted by blue circle is seen lateral to a-p web, which indicates a high compressive load acting on the nail resulting in overloading.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.Some important points are mentioned in the instructions for use for post operative activities these implants are neither intended to carry the full load of the patient acutely, nor intended to carry a significant portion of the load for extended periods of time.For this reason, post-operative instructions and warnings to patients are extremely important.External immobilization may be employed until x-rays or other procedures confirm adequate bone consolidation.The implant is intended for temporary bone fixation.In the event of a delay in bone consolidation, or if such consolidation does not take place, or if explantation is not carried out, complications may occur, for example fracture or loosening of the implant or instability of the implant system.Regular post-operative examinations are advisable.The risk of post-operative complication is higher if patients are obese and/or cannot follow the recommendations of the physician because of any mental or neuromuscular disorder.Based on investigation, it can be ascertained that the breakage is caused gradually by the action of high dynamic and fluctuating loads resulting in a fatigue failure.But due to lack of vital information about the patient, period for which the implant is implanted and any x-rays of the procedure, we cannot exactly say what caused this fatigue failure resulting in breakage of the nail.If more information is provided, the case will be reassessed.
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