The thickness of the cartilage in our knee joints is only about 3mm for men on average, and even lower for women, only about 2.7mm on average, which is as thick as our common dollar coin, and the cartilage is not regenerative after wear and tear, which means the wear and tear of our articular cartilage is irreversible. So, when our knee joints receive damage, what distress signals will be issued? 1, the knee joint distress signal: (1) stiff: stiff joints, feel inflexible activities? (2) pain: up and down stairs knee pain? (3) swelling: joint swelling? (4) card: walking knee stuck, activities and good? 2, received a distress signal from the knee what to do? If, the knee sends these distress signals you have to pay attention to. This means that our knee joints may have begun to appear problems in daily life will need to pay attention to the protection, for example, excessive obesity patients need to appropriate weight loss, to avoid prolonged exposure to a posture; pay attention to cold and dampness, warmth, to avoid excessive strain on the knee joints; try to minimize the up and down the steps and so on, so that the knee joints flexion weight-bearing exercise, in order to reduce wear and tear on the articular cartilage. You can take hot compresses, physical therapy, can take oral anti-inflammatory analgesic drugs and other ways to relieve the symptoms. Muscle strength training to exercise the quadriceps muscle, such as the following training methods. Static squatting against the wall: back against the wall, feet forward and apart, shoulder width, so that the thighs and calves into a close to 90 degrees (slightly less than 90 degrees) angle, adhere to 20 seconds, slowly relax, 20 times per group, 10 groups per day. If necessary, the doctor needs to decide whether to take surgical treatment according to the actual situation of the patient.