The knee, the largest and most complex joint in the body, is one of the few joints in our body that can only move in one direction. The knee is also the largest weight-bearing joint in the human body, and the average knee joint in a normal person can carry 35 kg of weight. The more weight you carry, the greater the chance of wear and tear on the joint cartilage, and the tendons are prone to injury, resulting in faster degeneration of the knee joint. What are the weight-bearing multiples of the knee in different states? 1. When lying down, the weight-bearing of the knee is almost 0. 2. When standing up and walking, the weight-bearing of the knee is about 1 to 2 times. 3.When walking up and down a slope or up and down a staircase, the weight on the knee is about 3 to 4 times. 4.When running, the weight of the knee is about 4 times. 5.When playing ball, the weight of the knee is about 6 times. 6, squatting and kneeling, the weight of the knee is about 8 times. For example: a person weighing 50kg, for each step, the knees have to bear about 200kg of weight. (50*4 times) How to spend the life of the knee 1.Before 15 years old The knee joint is in the developmental stage, and most of the growing pains in adolescence occur near the knee joint. 2. From the age of 15 to 30, the knee joint is in a “perfect state” and works tirelessly. As long as the knee joint tissue is not damaged, you will not feel its presence. 3, 30 ~ 40 years old Patellofemoral cartilage has early mild wear and tear, there will be a period of weakness, short-term knee pain, lasting a few weeks to a few months, some people will not even notice. Patellofemoral cartilage is a 3 to 5 mm thick layer of clear cartilage in the human knee joint that cushions the knee joint from the impact of movement. However, because the patellar cartilage has no nerve distribution, it will only sound an “early warning signal” once during the vulnerable period before the full layer wears out, and strenuous exercise should be avoided during this period. From this time on, the knee joint can no longer be used as you wish. 4. 40 to 50 years old After walking long distances, the inside of the knee joint tends to become sore and painful, which is relieved by rubbing it with your hands. In the knee joint, the role of the meniscus is to cushion vibration and maintain stability. Since 60% of the body weight is supported by the medial side of the knee, the degeneration of the medial meniscus occurs earlier. Because of the nerve distribution in the meniscus, people can feel soreness during the degeneration process. The arrival of this phenomenon reminds people that it is time to start taking care of their joints. 5, over 50 years old, the knee joint will feel obvious pain, this is because the “life” of the patellar cartilage has reached, the cartilage full layer wear, arthritis has been generated. This is the time to conserve the use of the joint, reduce strenuous exercise, especially stairs and climbing, and use crutches if necessary to reduce the pressure on the knee joint. What are the causes of knee pain 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 the tissue around the joint is prone to fibrous adhesions due to inflammation, so the elderly often feel stiffness in the knee joint. This is why the elderly often feel stiffness in their knee joints. When they move, they will make a “clicking” sound or frictional sound, and when they are cold or overly active, they will experience pain, swelling, and fluid accumulation in the joint cavity, and in severe cases, they will have deformed joints and become disabled. Specifically, the causes of knee pain in the elderly are as follows: 1. Chronic synovitis Chronic pain and swelling of the knee joint. Synovial effusion and synovial hypertrophy can be seen on physical examination. 2, patellar deviation, soreness and weakness of the knee joint after activity, improving after rest, pain during half squatting. 3, free body in the knee joint The patient’s leg is weak or has a feeling of joint jamming, and there is a friction sound under the patella. 4, prepatellar bursitis History of trauma, causing prepatellar pain, localized pressure pain on physical examination. 5, osteoarthrosis After sitting or squatting for a long time, when standing up or going up and down, the joint pain is obvious and relieved after rest. 6, pseudogout More male patients, mostly in the knee joint. The painful swelling, high skin temperature and limited function during the attack. x-ray film shows calcification of meniscus and articular cartilage surface. 7, femoral head necrosis Hip joint lesions have knee pain symptoms. What are the painful parts of the knee joint 1. pain in the lateral iliotibial band of the knee. 2.The front knee pain around the knee, also called patellofemoral joint pain. 3, Pain above the knee, which may be quadriceps tendonitis. 4, pain above the kneecap or on the inside of the upper tibia, which may be bursitis. How to take care of sore knees on a daily basis 1. Don’t walk for too long, and rest immediately when your knee feels uncomfortable. 2, do not do heavy exercise, such as running, high jump, long jump. 3, avoid half squat, full squat or kneeling position. Such as squatting horse stance. 4, do not do the knee joint half flexion rotation action, to prevent half plate injury. 5, maintain the ideal 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. 8.Avoid trauma and overwork. 9, the choice of shoes is very important. Shoes a pair of shoes that fit, not only can you walk comfortably, but also can reduce the impact and pressure on the knee during exercise. 1, the instep part of the foot can be closely combined with the shoe, width, length are appropriate, can correctly maintain the arches of the foot. 2, the weight of the shoe to light appropriate, the sole should not be too soft, and to a little thickness. 3, the heel of the shoe can be about 2-3 cm high, the sole is too flat is easy to walk when fatigue. 4, shoes with non-slip pattern on the sole. Knee pain in the elderly, more leg lifting more tiptoe Lie on your back, one side of the lower limb straight, the other side of the lower limb bend knee and hip so that the thigh as close to the chest as possible, and then alternately practice the other side of the lower limb. When there is nothing, back against the wall, as close as possible, up to quickly lift the heel, hold for 5 seconds and then put down, 10 times for a group, each time do 3-5 groups. This is also a good way to increase the stability of the ankle joint, especially for people who walk a long time foot pain.