What are primary varicose veins of the lower extremities? Varicose veins are not difficult to understand, but varicose veins are divided into primary varicose veins and secondary varicose veins. Primary varicose veins in the lower extremities, also known as simple varicose veins, are a disease that is confined to the superficial venous system of the lower extremities and is the most common type in clinical practice. Here, primary varicose veins are first introduced to you. Why are there primary varicose veins in the lower extremities? First of all, it is important to understand that there are three types of blood vessels in the human body: veins, arteries, and capillaries. Among them, venous valves are present in veins. Here, you can temporarily think of the venous valve as a one-way open gate. The venous blood flow in the lower extremities is from bottom to top, and the venous valves open and blood flows through, during normal reflux. After the blood flow passes, the blood flow returns downward because of the presence of gravity and other factors, and at this time, the venous valve closes, preventing the return of venous blood flow. Once the function of the venous valve is impaired, resulting in incomplete closure, which in turn causes the venous blood flow to return downward. The reflux of venous blood causes thinning of the lower venous wall, which results in the varicose vein masses seen in everyday life. What are the causes of primary varicose veins in the lower extremities? Weakness of the venous wall, venous valve defects and elevated pressure within the superficial veins are the main causes of superficial varicose veins. Varicose veins of the lower extremities mostly occur in people who are engaged in permanent standing work, high intensity of physical activity or are sedentary and less active. Various causes of venous vasodilatation, weakened calf muscle pump, and venous valve insufficiency can lead to downward regurgitation of blood flow in lower extremity veins, and once regurgitation occurs, varicose veins are easily caused. The main factors of varicose veins of lower limbs are: 1, long-term standing work: long-term standing work, due to the relationship of gravity can cause the lower limb veins blood reflux difficulties, over time will lead to thickening of the venous lumen, once the venous lumen thickening to the extent that the venous valve can not be completely closed, and will further aggravate the venous blood downward reflux. 2, heavy physical labor: long-term heavy physical labor can cause the increase of lower limb venous pressure. 3, tall, thick and obese: due to obesity, resulting in the increase of gravity, the lower limb venous blood reflux is affected. 4, abdominal pressure increase and pregnancy: abdominal pressure increase can affect the lower limb venous reflux, any factors that lead to abdominal pressure increase can cause the occurrence of varicose veins in the lower limbs. After women’s pregnancy, in addition to increased abdominal pressure, the enlarged uterus can compress the iliac vein and obstruct the return flow of blood to the lower limbs, causing varicose veins in the lower limbs. 5, other factors: including eating habits, sedentary work.