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An event regarding instability involving a triathlon insert was reported.The event was confirmed via medical review.Method & results: product evaluation and results: visual inspection: visual inspection of the returned device noted the following: the returned device was examined with the aid of a stereomicroscope at magnifications up to 50x.Damage was observed on the distal and anterior surfaces of the insert which is consistent with the explantation process.Backside impressions on the distal surface of insert are consistent with contact against a tibial base plate.Damage was observed on the articulating surface of the insert which is consistent with contact against the femoral component.The damage present on the articulating surface is consistent with burnishing, scratching, and third body indentations; these are common damage modes of uhmwpe.Damage consistent with delamination and material loss due to articulation against the femoral component was observed on the posterior portion of the medial condyle.Yellow discoloration, consistent with absorption of synovial fluid, was also observed on the insert.Dimensional inspection: dimensional inspection was not performed because the event does not relate to device dimensions.Functional inspection: functional inspection was not performed because the event does not relate to device function.Material analysis: material analysis of the returned device noted the following: the damage present on the articulating surface, posterior portion of the medial condyle, was consistent with delamination and material loss.The damage on the articulating surface of the insert is consistent with burnishing, scratching, and third body indentations; which are common damage modes of uhmwpe.The yellow discoloration of the insert is consistent with absorption of synovial fluid.Based on the given information, no identifiable materials or manufacturing discrepancies were observed on the surfaces examined.Medical records received and evaluation: a review of the provided medical information by a clinical consultant indicated: after eight-and-a-half years in situ, a post-traumatic instability of the right total knee arthroplasty was treated by a thicker, more constrained tibial insert.There is no evidence this late clinical event was related to factors associated with implant manufacturing or materials.Product history review: a review of the device manufacturing records indicate that all devices accepted into final stock were free from discrepancies.Complaint history review: there have been no other similar events for the lot referenced.Conclusions: a review of the provided medical information by a clinical consultant indicated: after eight-and-a-half years in situ, a post-traumatic instability of the right total knee arthroplasty was treated by a thicker, more constrained tibial insert.There is no evidence this late clinical event was related to factors associated with implant manufacturing or materials.No further investigation for this event 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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