Knee bending pain can be caused by joint degeneration, trauma, chondromalacia patella, etc. It can be treated with general therapy, physical therapy, medication and surgery. 1. Joint degeneration: osteoarthritis of the knee joint, due to the irritation of osteophytes and the friction of degeneration of articular cartilage, pain symptoms may appear when bending the knee. It is necessary to reduce the knee flexion and extension activities, pay more attention to rest, under the guidance of the doctor oral celecoxib anti-inflammatory and analgesic treatment, can be injected into the joint cavity of sodium vitrate for nutritional softening of articular cartilage treatment, and in severe cases, the feasibility of knee arthroplasty. 2. Trauma: Knee fracture, meniscus and ligament damage caused by trauma can lead to pain when bending the knee. It is necessary to consult a doctor to clarify the damage situation, can use a brace or plaster for knee braking, can follow the doctor’s instructions to orally take Loxoprofen sodium for pain relief, the application of Panax ginseng tablets and other drugs to activate blood circulation and remove blood stasis treatment, if necessary, surgery to repair the damage. 3. Chondromalacia patella: Chondromalacia patella caused by chronic injury, overloading and malnutrition, etc., which can cause pain when bending the knee. It can be treated by massage and hot compresses in regular hospitals, and chondroprotective drugs such as glucosamine sulfate can be taken orally as prescribed by the doctor, and surgery is feasible when it is serious. When the knee bending pain should be timely medical consultation, under the guidance of specialized doctors to actively carry out appropriate treatment, will help early relief of discomfort symptoms.