An event regarding wear, disassociation and loosening involving a duracon stem was reported.The event was confirmed (wear through a mar; loosening through the clinician review of the medical records provided).Periprosthetic fracture occurred in the region of the tibial mrh baseplate therefore there is no allegation against the duracon stem for this failure.Method & results: device evaluation and results: visual inspection was performed as part of the material analysis report (mar).This inspection indicated: the parts were examined with the aid of a stereo microscope at magnifications up to 50x.The damage is consistent with contact against a hard object.The distal surface of the stem is shown in figure 7, with damage and an unknown material being observed.This damage is potentially due to contact against a hard object.The damages observed on the threads of the stem and baseplate are consistent with wear mechanisms due to cyclic contact against each other after the loss of their locking mechanism.Material analysis: a material analysis has been performed.The report concluded: damages were observed on the threads of the stem and baseplate.The damages observed on the threads of the stem and baseplate are consistent with wear mechanisms due to cyclic contact against each other after the loss of their locking mechanism.Burnishing, scratching and third-body indentations were observed on the insert.These are common damage modes of uhmwpe.Eds showed the stem was consistent with astm f136 alloy and the baseplate was consistent with astm f75 alloy.Based on the given information, no identifiable materials or manufacturing discrepancies were observed on the surfaces examined.Clinician review: a review of the provided x-rays by a clinical consultant indicated: loss of bone support around the entire tibial mrh, likely due to the infection episode in 2014 with incomplete treatment of the tibial infection resulting in progressive local osteolysis, with persistent relative fixation of the distal stem section has contributed to an overload condition on the screw connection between the two ultimately leading to disassociation between the two and requiring revision surgery.No device-related factors are associated with any of the implanted devices consistent with the type of failure.Device history review: all devices were manufactured and accepted into final stock with no relevant reported discrepancies.Complaint history review: there have been no other similar events for the reported lot.Conclusion: a clinician review of the provided medical records states the following; clinician review: a review of the provided x-rays by a clinical consultant indicated: loss of bone support around the entire tibial mrh, likely due to the infection episode in 2014 with incomplete treatment of the tibial infection resulting in progressive local osteolysis, with persistent relative fixation of the distal stem section has contributed to an overload condition on the screw connection between the two ultimately leading to disassociation between the two and requiring revision surgery.The device was returned and material analysis was performed which stated 'damages were observed on the threads of the stem and baseplate.The damages observed on the threads of the stem and baseplate are consistent with wear mechanisms due to cyclic contact against each other after the loss of their locking mechanism.' the investigation concluded that the wear, disassociation, periprosthetic fracture, and loosening was caused by loss of bone support around the entire tibial mrh, likely due to the infection episode in 2014 with incomplete treatment of the tibial infection resulting in progressive local osteolysis no further investigation is required at this time.If additional information becomes available to indicate further evaluation is warranted, this record will be reopened.
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