1.Deep vein thrombosis of the lower limb is mostly manifested as single leg swelling, and the swelling occurs more suddenly, so patients often do not know enough and think that it can be relieved automatically after enduring a few days. In fact, there is a greater risk, because the movement of the limb is likely to cause the formed deep vein thrombosis to loosen and dislodge, and once these vein thrombosis dislodged, with the venous blood flow back through the inferior vena cava into the pulmonary artery, it will cause pulmonary embolism, chest pain, breathing difficulties and even sudden death. 2.Left iliac vein compression syndrome Refers to the compression of left iliac vein due to the clamping of iliac artery in front and sacral headland in the back before the blood converges into vena cava, which causes a series of symptoms such as limb edema, superficial varicose vein, bruised nutritional disorder of lower limb soft tissue, and even lower limb venous thrombosis. Because of the deep location of iliac vein and the interference of intestinal gas, it is difficult to diagnose by general ultrasound, so it is often ignored. Moreover, a considerable part of doctors do not know enough about this disease, and often treat it as simple varicose veins surgery, as a result, the patient’s leg swelling is not relieved after surgery, and even induce deep vein thrombosis, resulting in medical disputes. For patients with varicose veins and combined with leg swelling, it is best to go to the specialized vascular surgery to clarify the cause and get regular and effective treatment. 3, lymphedema Often there is a history of filarial infection or repeated attacks of dermatitis, which makes the lymphatic flow of the lower limbs obstructed, causing soft tissue fluid in the body surface after repeated infections of subcutaneous fibrous connective tissue hyperplasia, fat sclerosis, limb thickening, skin thickening, rough, tough as elephant skin, also known as “elephantiasis”. The Department of Vascular Surgery of Yangzhou First People’s Hospital has rich clinical experience in the treatment of lower limb dermatosis, and after regular treatment here, you can fully recover from the pain of lower limb swelling.