The reported event could be confirmed, since the product was returned for evaluation and matches the alleged failure mode.The device inspection revealed the following: the received device shows a broken nail in the webs of the proximal lag screw hole.The proximal portion was not available for evaluation.The appearance of the breakage surface of the anterior web suggests that the nail breakage had its origin in this area.Several drill marks were found at the lateral entrance of the proximal through the hole around the posterior web and the center.The fracture pattern resembles a fatigue fracture evident by the appearance of lines of rest and the presence of a shiny surface.The appearance of the fracture pattern indicates that fracture has initiated from the anterior web and progressed through the cross-section.Gradually, alongside the anterior web, the posterior web also started getting fatigued and broke ultimately.Severe deformation (plastic deformation) was also observed on the medial side of the through-hole at the bearing point of the lag screw, which indicates towards the high loading on 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 op tech states that: ¿in the event the nail is damaged during lag screw reaming, the fatigue strength of the implant may be reduced, which may cause nail to fracture." [original statement] the instruction for use clearly indicates that: ¿the implantation affects the patient¿s ability to carry loads and her/his mobility and general living circumstances.For this reason, the surgeon must counsel each patient individually on correct behavior and activity after the implantation.The surgeon must warn the patient that the device cannot and does not replicate a normal healthy bone, that the device can break or become damaged as a result of strenuous activity, trauma, mal-union or non-union and that the device has a finite expected service life and may need to be removed at some time in the future.Explain the need to report unusual changes in the implantation area as well as falls or accidents even if the device or the site of operation did not appear to be harmed at the time.[.] 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.Conditions attributable to non-union, osteoporosis, osteomalacia, diabetes, inhibited revascularization and poor bone formation can cause loosening, bending, cracking, fracture of the device or premature loss of rigid fixation with the bone.¿ [original statement].Based on the above investigation and the available information, the root cause of the breakage is a combination of both patient and user related factors.The nature of deformation in the nail indicates towards high loading which can be attributed to patient's high weight, along with an intra-op miss-drilling potentially weakening the nail initially.Since x-rays were not provided, it cannot be ascertained if the fractured started healing or not.If any further information is provided, the complaint report will be updated.
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