Osteoarthritis can occur in all joints of the body, but is more likely to occur in the knee, hip and spine, which are heavily weight-bearing. Sometimes, the pain can be radiated, such as pain in the hip joint can be radiated to the inner thigh and near the knee joint. Patients with osteoarthritis may experience stiffness in the early stages of the disease, for example, when the knee joint is in a certain position for a long time, they may have difficulty moving and starting. As the disease worsens, joint instability, reduced range of motion in flexion and extension, and decreased walking ability, especially the ability to walk up and down steps, squat, run, and jump, may gradually appear. Some patients with advanced osteoarthritis may develop deformities of the lower extremities, with knee deformities being the most common, and patients may even have to rely on crutches to walk. Although osteoarthritis is more common in the elderly, it can still be effectively prevented in daily life, mainly by doing the following four things: First, try to avoid joint weight bearing. It is best for the elderly not to frequently go up and down stairs, lifting heavy objects, so as not to overload the joints and aggravate joint degeneration. Second, maintain body weight and prevent obesity. Because obesity can increase the burden on the joints, so once you are overweight, you should actively lose weight. Third, appropriate participation in outdoor activities to prevent excessive exercise. The elderly actively participate in outdoor activities is beneficial to physical and mental health, but must pay attention to avoid excessive exercise, so as not to cause joint, ligament and muscle damage. Fourth, a reasonable diet. Eat more food containing protein and calcium, such as milk and milk products, beans and soy products, fish and shrimp, seaweed, etc., which can not only supplement protein and calcium to prevent osteoporosis, but also nourish cartilage and joints and reduce arthritis symptoms.