Knee osteoarthritis (OA) is a chronic and progressive joint disease characterized by the degeneration of articular cartilage, subchondral bone sclerosis, and the formation of osteophytes. This condition leads to joint pain and stiffness, negatively affecting individuals' quality of life. Joint stiffness, decreased quadriceps strength, and impaired proprioceptive sensation result in functional limitations. Due to these symptoms, individuals experience difficulties in performing daily activities such as rising from a chair, walking, and climbing stairs. The aim of this study is to evaluate the effects of joint range of motion, balance, and muscle strength on functional capacity in patients with knee osteoarthritis.