Inclusion Criteria:  diagnosed with OA according to American College of Rheumatology clinical criteria for OA of the knee or hip;[14,15] being in the age range 18-65; and absence of other diseases affecting functions and daily life (orthopedic, neurological, cardiovascular, metabolic disease and lung pathology).  Exclusion Criteria:  comorbidity affecting lower extremity and functions (patellofemoral pain syndrome, rheumatoid arthritis, ligament tear, meniscus); previous lower extremity surgery; Intra-articular steroid or hyaluronic acid injection in the last three months cognitive impairments; pregnancy; and illiteracy.