The increase in life expectancy is leading to an increase in the average age of patients undergoing total knee arthroplasty (TKA), and, consequently, an increase in the number of revisions. The main cause of TKA failure is aseptic mobilization, which is described as the loss of integration between the prosthetic component and the bone in the absence of infection. This represents a significant impact on professional and economic resources for the Italian healthcare system. Aseptic mobilization can be caused by inadequate initial fixation of the implant and/or mechanical or biological loss of fixation over time, factors that often occur simultaneously. A careful, methodical evaluation of post-operative radiographs of TKAs remains an important diagnostic tool. The analysis of the causes of aseptic mobilization of TKAs and the associated economic impact in the Emilia Romagna region is useful for providing an estimate of the problem and identifying potential areas for improvement.

Inclusion Criteria:

• Patients undergoing knee prosthesis revision for aseptic mobilization
• Follow-up ≥ 2 years
• Willingness to participate in the study
• Both sexes
• Patients ≥ 18 years old

Exclusion Criteria:

• Patient refusal to participate in the study and sign the informed consent
• Simultaneous participation in other studies

The analysis will be conducted on implants performed in the Emilia-Romagna region from 2003 to 2022 and on implants performed at the II Orthopedic and Traumatological Clinic of the Rizzoli Orthopedic Institute during the same period