An event regarding wear/metallosis involving a bone screw was reported.The event was confirmed via clinician review of the provided medical records.Method & results: -product evaluation and results: the reported device was not returned; however, photographs were provided for review.The photographs show a recently explanted metal mdm liner, poly adm liner, and 4 screws sealed inside a poly bag.Nothing remarkable can be seen on these devices in the photos.-clinician review: a review of the provided medical information by a clinical consultant indicated: "this patient underwent primary total hip arthroplasty, a revision total hip arthroplasty for polyethylene liner disassociation, with metallosis, and then another revision for acetabular loosening with metallosis.The root cause of these events cannot be determined with certainty.The causes of both acetabular loosening, polyethylene, disassociation, and metallosis, are multi factorial, including surgical technique, especially in the way preparation is made for insertion of the femoral head on the trunnion and the mdm liner into the acetabulum, as well as proper insertion of the polyethylene liner into a primary acetabular cup.Also contributing can be patient factors such as activity level and bmi, as well as implant factors." -product history review: review of the device history records indicate 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 lot referenced.Conclusions: it was reported that the patient was revised due to loosening of the acetabular component and metallosis.The reported device was not returned; however, photographs were provided for review.The photographs show a recently explanted metal mdm liner, poly adm liner, and 4 screws sealed inside a poly bag.Nothing remarkable can be seen on these devices in the photos.It was not reported what devices caused or contributed to the reported metallosis, and the stem and head in this case were competitor devices.It is possible that the metallosis generated due to motion of the loose shell against the acetabular screws or between the metal mdm liner and the shell.The event was further confirmed via clinician review of the provided medical records: "the root cause of these events cannot be determined with certainty.The causes of both acetabular loosening, polyethylene, disassociation, and metallosis, are multi factorial, including surgical technique, especially in the way preparation is made for insertion of the femoral head on the trunnion and the mdm liner into the acetabulum, as well as proper insertion of the polyethylene liner into a primary acetabular cup.Also contributing can be patient factors such as activity level and bmi, as well as implant factors." no further investigation for this event is possible at this time.If devices and/or additional information become available to indicate further evaluation is warranted, this record will be reopened.H3 other text : not returned.
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