First of all, it is important to understand that swelling of the lower limbs is not a disease in itself, just like fever, it is only a clinical manifestation, and there are many different diseases that cause this manifestation. The point is to find the real cause of the disease lurking behind! Only then can we treat the cause. The human body’s lower limbs are made up of the following main “materials”: skin, muscle, fat, bone, nerves, blood vessels, lymphatic vessels; then, we can see at a glance that skin, bone, nerves, fat itself does not cause swelling, then the cause of swelling is only through the blood vessels and lymphatic vessels, so that The swelling of the lower extremities for unknown reasons, usually the following diseases: 1, venous valve insufficiency There are a lot of valves in the veins, and its role is like the wind box pulled by the cookhouse in the countryside, to ensure that the wind can only blow in one direction, so the valves can ensure that the blood flows in one direction, without backflow, when the valves are damaged (for many reasons, such as: varicose veins, long-term standing, old age degeneration, etc.), the blood will occur with the position of backflow, specifically: the legs do not swell in the morning, after the activity, to the evening legs are swollen, the reason we all understand, is because the damaged valve can not block the gravity of blood, backflow occurred. 2, heart disease The heart is like a pump, while discharging blood to the outside, while pumping blood to the inside; week after week, the cycle is endless! When the heart disease occurs, due to the contraction capacity is reduced, can not be timely blood discharge, so that also can not effectively pump blood, so that the vicious circle of “starvation in front, suffocating in the back”, resulting in venous stasis, soft tissue edema! 3, hypoproteinemia malnutrition, blood protein levels are too low, resulting in the blood can not “pull” water, water will be oozing out of the tissue to the high osmotic pressure, resulting in tissue edema! When our country was poor in the 1960s, many people had “swelling disease”, and this was the reason. 4.Deep vein thrombosis of lower limbs Deep vein thrombosis of lower limbs seriously affects human health, and there are many causes of deep vein thrombosis (I will write an article to tell you later), the common ones are: long-term bed rest, fracture, orthopedic surgery If the thrombus grows in the veins of the lower limbs, it will lead to the obstruction of blood flow back to the heart, which is not difficult to understand, just like a balloon, the bigger it is, the lower limbs will swell very much. Once the thigh starts to swell, it means that the thrombus has already blocked above the root of the thigh (above the level of the common femoral vein)! The swelling caused by the thrombus itself is not terrible, what is terrible is that the thrombus is not honest, it is easy to fall off, because the venous blood is to return to the heart, therefore, the fall off thrombus is easy to block in the heart and pulmonary artery, which is clinically called: pulmonary embolism; after the pulmonary artery is blocked, the blood cannot be pumped into the lungs, oxygen cannot enter the blood, and the person will be “suffocated”! suffocated”! Therefore, once deep vein thrombosis occurs, you must go to the hospital in time for regular anticoagulation and thrombolysis treatment! 5.Lymphatic system diseases Blocked lymphatic vessels will also cause lower limb edema, in the past, the cause of lower limb lymphatic vessels blockage is mostly caused by a parasite, also called “filariasis”, this microorganism will enter the lymphatic system, blocking the lymphatic vessels, due to blocked reflux, resulting in a high degree of lower limb edema! It is now rare! Nowadays, the causes of lymphatic vessels blockage are mostly due to surgical destruction of lymphatic vessels, inflammation of lymphatic vessels, etc. 6, arteriovenous fistula or other malformation lower limb arteriovenous fistula is either congenital or acquired, mostly due to trauma and other factors, as arterial pressure is very high, perfusion into the vein, resulting in higher venous pressure, the venous wall is very thin, water will be “squeezed” out of the blood vessels, resulting in edema. In short, there are many causes of lower limb swelling, the common ones are the above diseases, we develop unexplained edema, we must seek medical attention in time, early diagnosis, in order to effectively treat!