Old Zhang has been a driver for more than ten years and is 46 years old this year. In addition to driving, he loves cigarettes and wine; like most middle-aged men, he doesn’t love sports. In order to avoid always looking for a place to go to the toilet, Lao Zhang also rarely drink water, basically sitting in the car is a whole day. However, recently, the old Zhang always feel the calf stomach and sore and pain, a burst, but also some swelling, not only sitting is difficult, standing is also difficult. Old Zhang thought it was “bruises”, thinking of soaking feet, legs will be better, and the results did not get better. Old companion said it is better to go to the hospital to take a look at it, the old Zhang thought to endure, the result is not two days really can not help it, to the hospital for a checkup, the doctor diagnosed as lower extremity deep vein thrombosis. But let the old Zhang is puzzled, after dragging so many days, just went to the hospital to see the doctor to check has not started to cure, leg pain is actually lighter, then this time still want to treat it? Will the thrombus “melt away” on its own? Drinking less water and sitting for a long time, why is it easy to get lower extremity deep vein thrombosis? Many patients with lower extremity deep vein thrombosis (DVT) have experiences similar to Zhang’s. First, let’s see why the doctor suspected that Zhang was suffering from DVT. Let’s see why the doctor suspected that Zhang was suffering from lower extremity DVT. 1. This is a 46-year-old middle-aged man, a driver by profession, who has taken to drinking less water to avoid frequent trips to the toilet. Then, drinking less water will lead to body dehydration, blood concentration, and blood has a tendency to gather into thrombus, which is also called hypercoagulable state. 2, Lao Zhang is addicted to smoking, drinking, not much exercise, the blood lipid level is relatively high, and tobacco and alcohol, especially nicotine on the blood vessels are stimulated, over the years, the inner wall of the blood vessels are prone to breeding thrombus. In the risk scale of lower extremity DVT, there is an assessment of “whether the patient takes transportation for a long time”. That is to say, if the patient takes the transportation for a long time, and the position is narrow, it is easy to grow blood clots on the legs. A common example is economy class syndrome, in which the patient has to sit in the economy class cabin of an airplane for several hours (usually ≥6 hours) in a cramped location that is not easy to move around, so the blood from the lower extremities cannot return to the heart smoothly, and it tends to collect in the lower legs and form thrombi. Although Zhang was not flying, he drove all day long, and it was also easy to form lower extremity DVT. 4, Lao Zhang’s symptoms are more special – swelling, soreness, a burst, sitting, standing are not good, soak your feet, pounding the leg also did not relieve, which is the most common symptoms of lower extremity deep vein thrombosis. These four points are the most common symptoms of lower extremity DVT. If we summarize these four points, we can highly suspect that Lao Zhang has lower extremity DVT. What are the characteristics of pain caused by lower extremity DVT? The pain caused by lower extremity DVT is very characteristic. About 50% to 60% of patients with lower extremity DVT have leg pain, and the pain is usually concentrated deep in the calf, regardless of whether the thrombus is in the calf or spreads to the thigh or even the root of the thigh. The pain caused by DVT in the lower limbs is not quite the same as superficial phlebitis. Patients with superficial phlebitis can see a red line in the skin of the lower limbs in the direction of the blood vessels, usually on the inside of the leg, and the pain is in the thighs and calves, and mainly around the superficial blood vessels. Calf muscle or ligament strain can also lead to leg pain, with lower extremity venous thrombosis how to distinguish it? We can teach you 2 small methods that can be used at home – Homans’ sign (straight leg ankle test) and Neuhof’s sign (gastrocnemius muscle tenderness). Straight leg and ankle extension test: The patient lies on the bed, straightens the legs, and hooks the toes upward as much as possible. If the calf stomach hurts, it means that Homans’ sign is positive, which indicates that the pain is caused by DVT in the lower limbs 90% to 90%. Gastrocnemius muscle pain: patients lie on their backs, relax the lower limbs, let others put their hands under the calves, and press the calf stomach (gastrocnemius muscle), if the calf stomach is particularly tight and tough, or if there is a hard lump and the patient feels pain, it means that Neuhof’s sign is positive, which further suggests that intermuscular vein thrombosis in the lower limbs. What are the characteristics of leg swelling due to DVT in the lower limbs? The blood in the deep veins of the lower extremities flows upward from below and overcomes gravity to return to the heart, relying on the following principles: 1. There is a special structure in the veins of the lower extremities, the venous valve, which is equivalent to a single valve, so that the blood in the veins of the lower extremities can only flow upward and not backward. 2. 2, the human body whistling process, the formation of negative pressure, the lower extremity vein blood has a certain negative pressure attraction force. 3, people every step, calf muscles will lower extremity blood upward extrusion, so calf muscles also known as the “second heart”. Sitting for a long time will make the power of the “second heart” greatly reduced, blood concentration, high coagulation state is easy to form blood clots; thrombosis will also destroy the venous valves, resulting in the blood can not be normal back to the heart, stagnation in the legs, the calves will be easy to swell. About 80% of the patients with lower extremity DVT will have leg swelling, often one leg is swollen, rarely both legs are swollen. Some patients with high blood pressure take calcium antagonists and other antihypertensive drugs, there will be drug-induced leg swelling, are bilaterally symmetrical swelling. Nephrotic syndrome, nephritis will also be swollen legs, often all other parts of the body will also be swollen, especially the face and eyelids, edema is obvious. Some people are susceptible to fungal diseases such as athlete’s foot and gray toenails in the summer, which block lymphatic vessels in the lower extremities leading to edema of the lower extremities, which is usually confined to the lower calves, near the ankles, and is painless. These swellings are often quite different from those caused by deep vein thrombosis of the lower extremities. Will the pain and leg swelling appear when I stand and disappear when I lie down? No. As long as a blood clot has taken root in the deep veins of the lower extremities, it is very difficult for it to go away on its own, much less with more rest or lying down. Not only will the blood clots not go away, they will continue to grow.