In aseptic loosening of arthoplasties (hip, knee), inflammation leads to dissolution of the bone and progressive implant loosening. These processes are the main cause of follow-up surgery. There is a great need for action to detect the onset of implant loosening at an early stage in order to take countermeasures. The project aims to identify factors (“biomarkers”) which (1) predict aseptic implant loosening, (2) can identify affected patients, (3) distinguish aseptic implant loosening from other causes of implant failure, (4) are able to provide insight into the development of aseptic implant loosening in order to avoid it in the future. The Erwin Röver-Stiftung (https://www.erwin-roever-gruppe.de/index.php) now funds our project in which we strive to answer these questions.