The common reasons for walking knee thumping are physiological ringing, pathological reasons such as knee joint disease, meniscus injury. 1. Physiological ringing: the knee joint in the activities caused by synovial membrane, ligament or cartilage friction, so as to sound belongs to the physiological factors, generally will not cause harm to the joints, and there is no joint pain and other uncomfortable symptoms. 2. Knee joint disease: when there are pathologic diseases in the knee joint, such as osteoarthritis and osteophytes, the structure of the knee joint will be damaged, and it is easy to be limited in the activities of the knee joint, which will make a popping sound. It is usually accompanied by joint pain or joint swelling. 3. Meniscus injury: After meniscus injury, tibia and femur will have friction when the knee joint is moving, which will cause the knee joint to rattle when it is moving. When the symptoms are mild, there is only pain and no limitation of activities, but when the symptoms are severe, there is often joint swelling and limitation of activities. Walking knee thumping may also be caused by other reasons, once the popping sound occurs frequently or accompanied by pain, should go to the regular hospital in time to identify the cause and targeted treatment.