The common clinical symptoms of osteoarthritis of the knee include localized pain, activity limitation, joint deformity and so on. 1. Localized pain: in the early stage of osteoarthritis of the knee, the pain is mild and usually relieved after resting, but when the osteoarthritis is serious, the patient may have persistent pain in the knee. 2. Restricted movement: Patients with osteoarthritis of the knee have typical morning stiffness, which is a feeling of tightness and rigidity in the knee joints in the early morning, and is usually alleviated by movement. As the disease progresses, it may eventually lead to severe limitation of activities or even disability. 3. Joint deformity: the patient’s knee joint may develop osteophytes or synovial hyperplasia resulting in joint enlargement, causing changes in the shape of the knee joint. Clinically, patients with osteoarthritis of the knee joint may also have symptoms such as muscle atrophy and bone rubbing sound, etc. If the patients have the above symptoms, they should consult a doctor for examination in time.