What would you do if you found yourself with swollen legs that day? Generally speaking, many people who find their legs swollen will choose to go to the hospital for examination and treatment. But when they go to the hospital, many people will be confused about which department to go to for examination and treatment. Perhaps many people will not hesitate to choose to go to the cardiology department, nephrology and other familiar departments. Because they know that many serious heart and kidney diseases, such as cardiac insufficiency, renal insufficiency and nephritis, can cause swelling of the lower limbs. However, is the swelling of the lower limbs necessarily caused by these diseases? The answer is, of course, no. In fact, many people do not know that the most common cause of lower limb edema is not heart disease, kidney disease and other diseases. Rather, it is the type of disease I want to tell you today – lower limb venous disease. It mainly includes deep vein thrombosis and lower extremity venous valve insufficiency. The former is a more serious lower extremity venous disease, patients often have a history of lower extremity venous disease or lower extremity venous injury, usually occurs in one limb, the main manifestation is sudden lower extremity swelling, pain, when palpation found in the limb tension, pressure pain is obvious, skin temperature is often higher than the contralateral limb, skin color is more dark than the contralateral side. Ultrasound of the veins of the lower extremities may provide a clear diagnosis. Thrombolytic therapy with inpatient placement of an inferior vena cava filter is now routinely required. The latter is mostly bilateral and chronic, often with a history of varicose veins, and the main symptoms are swelling and heaviness in the lower extremities, and in some patients, soreness and itching. Examination often reveals obvious depressible edema in the lower extremities, without obvious pressure pain. Dorsal foot artery fluctuations are usually palpable. Ultrasound and nondestructive examination of the veins of the lower extremities may assist in making a definitive diagnosis. These two diseases, which are very common in clinical practice, especially the latter, will occur in almost every person during their lifetime. Deep vein thrombosis is easy to diagnose clinically because of its typical symptoms, so I don’t need to go into too much detail. I will carefully describe the venous insufficiency of the lower extremities. In clinical practice, we often encounter patients who have had swelling in both lower extremities for many years without finding the cause. Most of them have been examined and treated in cardiology and nephrology. But because no clear cause was found. So the effect of their treatment is very unsatisfactory. This not only puts a lot of pressure on the patients psychologically, but also puts a big burden on the economy. Many patients finally had to give up treatment. I have met several such patients who gave up treatment because the long-term treatment was too costly and unsatisfactory. In fact, swelling of the lower limbs is not a rare and serious disease. Rather, it is a venous valve insufficiency of the lower extremity that I just have to tell about. Its cause is mainly venous reflux obstruction caused by venous valve insufficiency in the lower extremities. Treatment, although not ideal, is not usually a serious problem with this disease.