Osteoarthritis is also known as age-related arthritis or degenerative arthritis. Many people believe that osteoarthritis is an inevitable disease of the elderly, the result of natural wear and tear on the joints over time. In recent years, however, questions have been raised about this view. This is because the changes seen in surgically removed specimens of femoral heads suffering from osteoarthritis far exceed those developed by the natural degeneration of the femoral head in the elderly. Moreover, very few degenerative features were found in the articular cartilage of the elderly, and no physical or biochemical changes were evident. Accordingly, osteoarthritis in the elderly may begin at a young age as a result of a series of long-term pathophysiological stimuli to the bone joints. For example: repeated chronic injuries, excessive and repeated use as well as developmental abnormalities and secondary deformities. In addition, obesity increases joint weight bearing, which can cause and accelerate the onset of osteoarthritis; metabolic diseases such as diabetes can also trigger osteoarthritis. Osteoarthritis is more common in women than in men, and the affected areas are mostly found in the interphalangeal joints and hip and knee joints. Pain is a common symptom. In the early stage, the pain is mild and occurs during activity and is relieved after rest. The pain is activity-related, and rest can reduce the pain, while activity, especially weight-bearing activity, can make it worse. Common signs include joint enlargement, tenderness, rattling with movement, deformity, and functional impairment. Diagnosis of osteoarthritis is generally not difficult and can be made based on symptoms, signs, and radiographs. So, how should we treat this disease after a clear diagnosis? First of all, you should pay attention to proper rest and weight loss, and consistently participate in appropriate physical exercise to maintain the coordination of nerves and muscles and prevent atrophy of muscles, tendons and ligaments. Correct various incorrect postures in life and work, and reduce the damage caused by repetitive impact of activities on joints. Secondly, physical therapy plays an important role in the treatment of osteoarthritis, especially for those who cannot relieve the symptoms with medication or cannot tolerate it. The goal of physical therapy is to maintain or increase the range of motion of the joints, increase the strength and endurance of the muscles around the joints, and increase the ability to move outdoors. Third, many anti-rheumatic drugs are effective for osteoarthritis, but their effect is primarily to relieve symptoms. Medication is only part of the treatment. Fourth, surgery is almost the only option for patients with severe joint damage and functional impairment. osteotomy may be considered for O- or X-leg; intra-articular free bodies or cartilage fragments can contribute to the deterioration of osteoarthritis, and the removal of these free bodies and cartilage fragments often greatly reduces pain and other symptoms; artificial joint replacement is a well-established technique that relieves pain and improves range of motion, and is particularly suitable for patients with severe osteoarthritis. It is particularly suitable for patients with severe osteoarthritis.