Inclusion Criteria:  age more than 18 patients underwent total knee arthroplasty without controindications for this procedure patients enrolled in PatientsReportedOutcomesMeasureS (PROMS) study  Exclusion Criteria:  age less than 18 comorbility that make difficult come back for follow-up patients with allergy at materials used in Radiostereometry tecnique infection anemia, obesity, osteoporosis pregnancy