Traina, FrancescoFrancescoTrainaMorlock, MichaelMichaelMorlockMayer, Richard T.Richard T.MayerHart, AlisterAlisterHart2024-01-042024-01-042023-051st EFORT European Consensus Medical & Scientific Research Requirements for the Clinical Introduction of Artificial Joint Arthroplasty Devices (2023)https://hdl.handle.net/11420/44907Question: Modularities / Interfaces How can the in vivo behaviour of interfaces between implant components (e.g. head-conus-connection, not articulation partners) be assessed clinically, for example concerning the consequences of micro motion or corrosion processes? Summary / Recommendation: The in vivo assessment of the behaviour of interfaces, like the clinical consequences of micro-motion or corrosion processes, includes an appropriate patient/implant stratification, plain X-rays, serum metal ion levels and cross-sectional imaging (MARS MRI). A patient-implant stratification is mandatory to predict the cases at higher risk of complications, when close surveillance is appropriate. In vivo clinical manifestations of interface damages are adverse local tissue reactions (Cr-Co alloy modularity in single or dual taper implants) or catastrophic failures (Ti alloys in dual taper implants). The cases at high risk encompass: active overweight male patients, high offset, 36 mm heads or larger. In these cases, a simple X-ray should be performed and infection ruled out (inflammation markers and synovial fluid aspiration). Second level investigations include serum metal ion levels in Cr Co alloys (single taper: cobalt level >1 ng/ml (1 ppb) and the Co/Cr ratio >2/ dual taper: thresholds can be as high as 2.8 and 3.8). Ti blood ion assessment in dual taper Ti implants is less standardized probably not useful. Cross sectional imaging (MARS MRI, or CT and US as second choices) may identify adverse local tissue reactions, usually >3mm thick walled cystic/solid masses.enMedicine, HealthEngineering and Applied OperationsResearch Reporthttps://www.efort.org/wp-content/uploads/2023/05/EFORT_Consensus.pdfResearch Report