The reported event could be confirmed, since the device was returned for evaluation and matches the alleged failure mode.Device inspection revealed the following: the received nail is found to be completely broken in the webs of the proximal lag screw hole.The fracture appears to have originated from the posterior web in a fatigue manner, as evident by the lines of rest/waves.The anterior web shows signs of instantaneous fracture which is a result of sudden loading after the breakage of the posterior web.Miss-drilling marks are also evident majorly on the anterior web, running from lateral entrance to the medial through the bore.Very slight miss-drilling marks appear on the posterior web.The effect of miss-drilling on the breakage in this case cannot be quantified.On the medial side of the distal portion of the nail, the bearing point shows signs of permanent deformation indicating towards overloading of the nail.A review of the device history for the reported lot did not indicate any abnormalities.No corrective actions are required at this time.No indications of material, manufacturing or design related problems were found during the investigation.A review of the labeling did not indicate any abnormalities.The instruction for use states that ¿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.¿ based on the investigation and the available facts, the root cause of the issue is majorly attributed to patient related factors.The fracture area of the nail exhibits a fatigue fracture and a plastically deformed medial side which indicates towards constant overloading in a cyclic manner.The overloading can be explained by the non-union of fracture site in the patient, as received through the additional information.If the device is returned or if any additional information is provided, the investigation will be reassessed.
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