After middle age, the tendons and ligaments of the knee joint begin to undergo degenerative changes, the synovial fluid secretion in the joint cavity decreases, the bone surface of the joint rubs together for a long time to form bone wear and tear, and the tissues around the joints are prone to fibrous adhesions due to inflammation and other reasons, so the elderly often feel stiffness in the knee joint. Activity will be issued “click” sound or friction sound, in the cold or excessive activity will induce pain, swelling, joint cavity fluid, serious will also make the elderly joint deformity, the formation of disability. Specifically, the causes of knee pain in middle-aged and elderly people are as follows: 1, chronic synovitis manifested as chronic pain and swelling of the knee joint. The examination can see synovial fluid, synovial membrane hypertrophy. 2.Patellar deviation Knee joint pain and weakness after activity, better after rest, and pain when half squatting. 3, Knee joint free body The patient’s leg is weak or there is a sense of joint jamming, and there is friction sound under the patella. 4.Pre-patellar bursitis There is a history of trauma, which causes pre-patellar pain, and there is localized compression pain on examination. 5.Osteoarthropathy Joint pain is obvious when getting up after sitting or squatting for a long time, going up and down the stairs, and relieved after resting. 6.Pseudogout Male patients, preferably in the knee joint. Swelling and pain, high skin temperature, functional limitation during attack. x-ray film shows calcification of meniscus and articular cartilage surface. 7.Necrosis of femoral head Hip joint lesions with knee pain symptoms. How to daily health care for knee pain? 1.Don’t walk for too long, and rest immediately when your knees feel uncomfortable. 2.Do not do large exercise, such as running, high jump, long jump. 3, avoid half squatting, full squatting or kneeling posture (such as squatting horse stance). 4, do not do half-flexion rotary movement of the knee joint to prevent half-plate injury. 5.Maintain ideal body weight to reduce the burden on the knee. 6, pay attention to the warmth of the knee, you can wear long pants, knee pads to protect the knee. 7, less heavy lifting, less wearing high heels. Avoid trauma and excessive labor. 9, choose the right shoes, not only can you walk comfortably, but also can reduce the impact and pressure on the knees during exercise.