An event regarding wear involving a triathlon insert was reported.The event was confirmed.Method and results: device evaluation and results: material analysis concluded; evenly distributed wear patterns, discoloration, burnishing, scratching and third body indentations were present on the triathlon insert.Discoloration is attributed to the absorption of synovial fluid.Burnishing, scratching and third body indentations are common failure modes of uhmwpe during in vivo use.No material or manufacturing defects were observed on the surfaces examined.Medical records received and evaluation: a review of the provided x-rays by a clinical consultant indicated: complex malposition of components including 3 degrees varus deformity, 6 degrees obliquity of a low joint line and 7 degrees posterior baseplate slope, has contributed to quite likely early instability and a cosmetic disturbing appearance in the knee requiring revision.The observed ¿abrasive wear¿ should be interpreted as sign of flexion instability in the knee consistent with the other facts and findings reported including the mar.No patient or device-related factors were evident.Device history review: the device was manufactured and accepted into final stock with no reported discrepancies.Complaint history review: there have been no other similar events for the lot referenced.Conclusions: material analysis concluded that the burnishing, scratching and third body indentations noted on the insert are common failure modes of uhmwpe during in vivo use.No material or manufacturing defects were observed on the surfaces examined.The medical review indicated that complex malposition of components has contributed to quite likely early instability and a cosmetic disturbing appearance in the knee requiring revision.The observed ¿abrasive wear¿ should be interpreted as sign of flexion instability in the knee consistent with the other facts and findings reported including the mar.No further investigation is possible at this time.If additional information becomes available to indicate further evaluation is warranted, this record will be reopened.
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