Knee osteoarthritis (OA) is also known as degenerative joint disease, is typically the result of wear and tear and progressive loss of articular cartilage. It is most common in the elder population. It results from functional disability and altered knee biomechanics. Risk factors of Knee OA include; older age, genetics and obesity, female gender. The aim of this study is to compare the effects of core stabilization exercises versus foot-ankle strengthening program on pain, physical function and quality of life in patients with knee osteoarthritis.