Persona Revision Knee System EMEA PMCF Study

Inclusion Criteria: * Patient qualifies for a revision knee arthroplasty with the Persona Revision Knee System. Full or partial/hybrid revision cases that fall within the revision knee indication are allowed to be included in the study (not first joint replacement). * Patient experiences severe knee pain and disability due to: The salvage of previously failed knee surgical attempts or for a knee in which satisfactory stability in flexion cannot be obtained at the time of surgery. * One-stage revision performed for infection OR * Second stage (reimplantation) of a planned two-stage revision. * Patient is ≥ 18 years. * Patient is skeletally mature. * Patient is willing and able to complete scheduled follow-up evaluations as described in the Protocol and Informed Consent Form. * Patient has participated in the Informed Consent process and is willing and able to sign the Informed Consent Form. Exclusion Criteria: * Patient received the study device for any condition not listed in the indications or in combination with a non-compatible device. * First Knee Replacement patients. * Patient with only inlay/bearing exchange/revision. * Patient requires simultaneous bilateral knee surgery for treatment of diagnosed condition. * Patient has any of the following contraindications: * Any active or suspected latent infection in or about the knee joint or distant foci of infection which may cause hematogenous spread to the implant site: In any case, the infection needs to be treated prior to the revision surgery. * Insufficient bone stock on femoral or tibial surfaces which cannot provide adequate support and/or fixation to the prosthesis. * Skeletal immaturity. * Neuropathic arthropathy. * Osteoporosis or any loss of musculature or neuromuscular disease that compromises the affected limb. * A stable, painless arthrodesis in a satisfactory functional position * Severe instability secondary to the absence of collateral ligament integrity. * Diagnosis of rheumatoid arthritis in conjunction with any of the following at the preoperative appointment: An ulcer of the skin, history of recurrent breakdown of the skin, use of steroids. * Patients in whom the Persona Revision Knee System is used as a temporary, interim, spacer-type, or destination-spacer construct are not eligible, including use in a 1.5-stage revision strategy or as the first-stage construct in a planned 2-stage revision. Enrollment is restricted to subjects in whom the Persona Revision Knee System is implanted as the surgeon-intended definitive revision knee arthroplasty following infection eradication. * Patient underwent contralateral total knee arthroplasty within 3 months of the planned index procedure or has a contralateral total knee arthroplasty planned within 3 months of the index procedure. * Patient is known to be pregnant or planning to become pregnant during the time they will be participating in the study. * Patient is a member of a vulnerable population group, such as * A prisoner. * A known alcohol or drug abuser. * Mentally incompetent or unable to understand what participation in this study entails. * Patient with suspected or confirmed metal sensitivity or allergy to the metals of the device.