Only a small percentage of joint pain is caused by trauma in daily life. Prolonged exposure of the joint to cold or a huge temperature difference in the environment is the main cause of joint pain. Knee pain conditions: 1. Fat pad strain, this injury occurs mostly in people who walk, climb or squat more frequently; 2. If the knee joint is slightly flexed, sudden excessive internal rotation and knee extension or external rotation and knee extension, it may cause meniscal tear; 3. If the synovial membrane is damaged by factors such as trauma or excessive strain, it will produce a large amount of fluid, which will increase the pressure in the joint, if not eliminated in time, it will easily cause joint adhesions, the general population will feel pain, swelling, pressure and pain in the knee joint, and the synovial membrane has a frictional sound; 4. If long-term overload will lead to swelling and pain in the knee joint, sometimes there will be frictional sounds in the moving joint. This condition is often accompanied by deformity and pain.