On 12.23.2021 the following event was reported to implant cast (b)(4): "patient implanted in (b)(6) 2015 with a ceramic pth on actinia ecofit ceramic from the implant cast laboratory.In (b)(6) 2016, surgical revision of the acetabulum following a ceramic fracture with insertion of a pe insert + change of broken ceramic head for a metal head.In 2017-2018, progressive onset of deafness then blindness, polyneuropathy in 2021, diagnosis of systemic metallosis evoked with blood co levels at 402.37g/l and blood cr at 454.81 g/l.(b)(6) 2021: removal of pth for loosening and metallosis.Placement of a contour ring in front of a bone defect with cemented pe cup, ceramic head, stem change.".
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After a ceramic head and ceramic inlay used in a total hip prothesis of a (b)(6) female patient broke, the components were revised using a metal head combined with a pe inlay.Consequently, the patient suffered from high blood levels of cobalt and chrome as well as metallosis.An optical inspection was not possible because implant cast (b)(6) had neither the parts nor images thereof at its disposal.However, the manufacturing protocols as well as the material certificates were flawless and showed no deviations.Additionally, neither the surgical technique nor the instructions for use showed any flaws.However, the corresponding surgical technique states that the used combination is strongly contraindicated after a ceramic fracture.The surgical technique also refers to a recommended course of action of the (b)(6) society for endoprosthetics.Here it is stated that even with a thorough debridement there will always remain ceramic particles after a fracture.Due to the higher hardness of the ceramic compared to metal this will always lead to three body wear with systematically high metal ion concentrations, which in turn will lead to serious complications like in the case at hand.Therefore, the used combination is not recommended by the (b)(6) society for endoprosthetics in this situation.Furthermore, a guidance document made by ceramtec, the manufacturer of the former head and inlay, also states that the combination of a metal head and pe-inserts should be avoided at all costs in this situation to minimize problems due to three body wear.Based on tests, the amount of abraded volume when using a metal head and a pe-inlay after a ceramic fracture is about 1000 times higher compared to a ceramic head with pe- or ceramic-inlay.All in all, since the information about a component change after a ceramic fracture being that widespread, it has to be assumed, that the surgeon should have known about the inherent risk of using a metal head and a pe-inlay after a ceramic fracture.Therefore, the implant cast (b)(4) does not see any product problem that caused the problems at hand and suspects a user error to be the root cause.(b)(4).
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