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Why do "earthworms" grow on my legs?
After standing for a long time, a network of blood will grow on the legs, and if you ignore it, these blue and purple blood streaks will swell up. It was as if earthworms had climbed up the legs, and even like tangled old tree roots, winding from the ankles to the thighs.
Medically, this condition is known as "varicose veins of the lower extremities" and affects 1 in 10 people on average.
In this issue, "Life Times" will take you to see the whole process of "earthworms" climbing up to the calves.
Audit Specialists
Wang Keqin, Chief Physician of the Department of Vascular Surgery, Beijing Chaoyang Hospital, Capital Medical University
The author and editor of this article丨Xu Wenting
Drawing丨Ma Hongliang
The vascular vein is a one-way street
The venous system is the conduit for the return of blood to the center, which is distributed throughout the body, and can collect the used blood of various tissues and organs, accounting for about 64% of the total body blood volume, so it is often called a blood bank.
In order to prevent the stored blood from backing up under gravity, the endothelium of the veins in the extremities protrudes inward, forming valves (venous valves) that contain elastic fibers that can be opened and closed freely, but only a one-way street with centripetal flow is opened.
When the valve is closed, it can tolerate pressures above 200 mm Hg, which is enough to carry the blood stored. Because the lower extremities are longer and it is more difficult for blood to flow back to the heart, the veins of the lower extremities usually have more valves than the upper extremities.
Prolonged sitting increases venous pressure in the lower extremities
Compared with arteries, vein walls are thin and less elastic. In addition, without the help of the heart's pump, the blood flow in the veins is slower, and the muscles that contract when moving or walking are needed to promote the return of blood to the heart and reduce the pressure in the veins.
Lower extremity venous pressure receptor position and activity are particularly affected, with the average ankle venous pressure as an example:
Only 12~18 mm Hg in the resting supine position;
up to 56 mm Hg when sitting;
Up to 85 mmHg in upright position.
When the lower limbs are active, the calf muscles can contract and drain 30~40 ml of blood each time, so that the venous pressure of the foot decreases by 60%~80%.
Sitting and standing in a resting state for a long time, without muscle assistance, will cause the veins on the distal side of the lower limbs to be in a state of high pressure and congestion. Long-term exposure to high pressure can also cause the valve to gradually thin, elongate, tear, and eventually atrophy, age, and incomplete closure, unable to prevent blood from flowing backwards.
Stagnant blood in the blood vessels
As a result, blood is trapped in the veins of the lower limbs, and the blood vessels are not only expanded laterally, but also stretched and deformed longitudinally. Crooked, pimple-protruding blood vessels protrude from the skin.
Starting with the veins in the ankles, the vein valves collapse one after another, and the varicose blood vessels spread to the periphery and above. Teachers, surgeons, nurses, hairdressers, cooks, restaurant waiters, etc., who usually need to stand for long periods of time, are at high risk of varicose veins in the lower extremities.
Long-term retention of blood may gradually form a clot near the venous valve, and the surrounding blood vessels may become red, swollen and inflamed.
Due to poor blood circulation, the ability to resist injury is reduced, and it is more likely to ulcerate when exposed to trauma or bleeding from a ruptured vein.
As the disease progresses, the valve is destroyed more and more, and the varicose becomes more and more severe, and there is no specific drug, and severe radiofrequency ablation or surgery is required.
-Finish-
Varicose veins are an irreversible phenomenon, and it is especially important to detect and stop further dilation in time.
Varicose veins of the lower limbs may have no obvious symptoms at first, and some patients often feel that the affected limbs are heavy, swollen and painful, and easily fatigued;
People with a long course of disease have pigmentation, itching, and eczema on the skin of the lower calf or ankle;
In some patients, blood circulation deteriorates and local tissue hypoxia decreases, resulting in reduced resistance to injury, and thrombophlebitis will be complicated by thrombophlebitis, which is manifested as redness, swelling, hard mass, tenderness, and even ulceration due to injury bleeding.
1. The pressure of varicose vein stockings is the largest in the ankle and gradually decreases along the leg upward, which can effectively prevent and relieve varicose veins, but cannot play a therapeutic role. It is best for patients to put it on in the early morning before they get out of bed and take it off when they go to bed at night.
2. Walking, swimming, cycling and other sports can not only improve blood circulation, but also reduce the rate of occurrence of new varicose veins.
3. In terms of diet, you should eat more high-fiber and low-fat foods and pay attention to weight control.
4. Avoid wearing tight clothing and high heels, do not stilt your legs, reduce sitting or standing for a long time, and high-risk groups can raise their legs for a period of time before going to bed every day. ▲
Editor of this issue: Luo Rong
Copyright Notice: This article is the original of "Life Times" and is not reproduced without authorization.