The reported event could be confirmed.Device inspection revealed the following: the received nail was found completely broken in the web.The evaluation of the broken surface revealed that the breakage originated from the anterior web.Significant step drill marks are visible around the inside surface of the anterior web as well.Visibility of lines of rest confirmed the breakage to be a fatigue fracture.The posterior web was chipped off rather quickly due to increased tension.Plastic deformation was found around the edge of anterior web due to rubbing of lag screw against it, post-breakage.There were abrupt ridges and other scratch marks which were caused during ex-plantation.Based on the investigation it was observed that the reason for breakage was fatigue stress.This was induced due to the damage done during the drilling for lag screw by a step-drill.Subsequently, the area around the damage, got weakened (reduction in fatigue strength) and over a period of time (10-11 months) the affected web of the nail broke in a fatigue manner.Since the patient is also being revised to an artificial hip joint, there is a possibility of a potential delayed healing, which could have also contributed in the failure, but due to unavailability any post op x-ray, it cannot be ascertained.Thus, based on the investigation the predominantly the failure happened due to a user related issue.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.If any further information is provided, the complaint report will be updated.
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