Investigation results were made available.Event description: it was reported that the products were implanted in 2003 and revised on (b)(6) 2020 due to acetabulum fracture.Patient had a fall.Stem was well fixed and remain in-situ.Review of received data: x-rays: an x-ray review has been performed by an hcp and can be summarized as follows: (b)(6) 2005- pelvic overview, right / left hip axial-view: inclination angle approximately 35 degrees, heterotopic ossifications on the right side.(b)(6) 2009 - pelvic overview, right / left hip axial-view: inclination angle unchanged, no suspicious findings on the right side.(b)(6) 2012 - pelvic overview, right / left hip axial-view: compared to the previous x-rays no relevant changes on the right side.(b)(6) 2014 - pelvic overview, left hip axial-view: unchanged inclination angle on the right side.Small radiolucent areas at the acetabular roof neat to the implant.At the lower rim of the cup a radiolucent zone is visible.(b)(6) 2020 - pelvic overview: compared to the previous follow up of (b)(6) 2014 a protrusion of the cup with flattened inclination angle and breakthrough in the acetabular bottom can be identified.A vertical fracture line might also be delineated.(b)(6) 2020 - pelvic overview, right hip axial-view: situation after revision surgery on the right side.Surgical report: surgical report, dated (b)(6) 2020: due to a stumble fall patient suffered the periprosthetic fracture.A prosthesis that has been in place for a long time has evidently developed osteolysis in the acetabulum and a stumble fall was enough to cause the fracture.It¿s a high fracture with a multi-fragmentary component of the posterior wall, but the stem is fitting stuck.The joint is obliterated, the capsule is 15-25 mm thick with pronounced fibrosed synovitis.No obvious metallosis.Biopsies are taken from various locations for histopathological and microbiological examination.The cup is obviously unstable and can be removed with a single tincher after it has been tilted further with a pestle.The anterior acetabular wall is fractured, the column may still be in continuity in a thin area.The tear drop and lamina quadrilateralis are unstable.The posterior column is also unstable with a multi-fragmentary posterior wall.After stabilization of the anterior and posterior column with screws fitting of the acetabular bottom with cement insert of a reinforcement ring with hook and cementing of a müller flat profile cup durasul in 40 degrees - 45 degrees and 15 degrees - 20 degrees anteversion.After removal of the femoral head the cone is moderately corroded.The traces of corrosion can be rubbed off with a compress.After trial reposition with a l-head the correct relative implant position is confirmed without instability under tension as well as in extension and external rotation with telescoping of approximately 5 mm.Lab results: sampling date (b)(6) 2020 -whole blood : cobalt 37 nmol/l (reference < 66 nmol/l).Chrom 29 nmol/l (reference < 75 nmol/l).Product evaluation: visual examination: the head, insert and shell were received for investigation.The articulation surface of the head shows numerous fine scratches as well as some individual coarse scratches.The head taper is inconspicuous.On the articulation side some scratches and cuts most likely from the revision surgery can be observed on the polyethylene rim of the insert.In one area possible signs of delamination can be observed.On the articulation surface numerous fine scratches can be seen.Further, individual coarse scratches are visible in one area.The backside of the insert is slightly yellowish discolored.The pole pin of the insert is slightly damaged and deformed.The indentations from the fixation spikes on the shell can be observed indicating a proper fixation of the insert in the shell.On the anchoring side of the fitmore shell the sulmesh shows some bone attachments.In some areas the sulmesh seems to be polished and/or scratched.The inside of the shell looks inconspicuous.Review of product documentation: device purpose: this device is intended for treatment.Product compatibility: the product combination was approved by zimmer biomet.Dhr review: review of the device history records identified no deviations or anomalies during manufacturing.Conclusion: it was reported that the products were implanted in 2003 and revised on (b)(6) 2020 due to acetabulum fracture.Patient had a fall.Stem was well fixed and remain in-situ.A revision surgery was performed of the right hip idue to a periprosthetic transversal acetabular fracture with fracture of the posterior wall on the right side.In the preoperative indication, evidently developed osteolysis in the acetabulum is mentioned and the fall event was enough to cause the periprosthetic fracture.In the preoperative x-ray documentation of the right hip joint from (b)(6) 2020, radioloucent areas close to the implant in the area of the acetabular roof can be seen as possible indications of osteolytic changes.Intraoperatively, the presence of metallosis is explicitly excluded.Based on the investigation the reported event can be confirmed.The investigation did not identify a nonconformance or a complaint out of box (coob).A direct correlation between the acetabular osteolysis and the acetabular fracture caused by a fall 17 years after implantation of a total hip arthroplasty cannot be confirmed on the basis of the available medical findings and reports.A macroscopically recognizable metallosis in the hip joint is explicitly excluded intraoperatively.The metal ions determined preoperatively are not increased.A preoperative increase in the metal ion values of cobalt and chrom in the blood could be excluded by laboratory tests.Based on the given information and the results of the investigation, we identified the root cause of the fracture is most likely the patient's fall which is in alignment with the surgeon's evaluation.The need for corrective measures is not indicated and zimmer switzerland manufacturing gmbh considers this case as closed.Zimmer biomet's reference number of this file is (b)(4).The following reports are associated with this event: 0009613350-2020-00185-1.
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