Leg pain after walking is a sign of atherosclerosis of the lower extremities, a considerable number of older people have such experience, walking for a period of time after the emergence of pain on one or both sides of the calf belly, and even forced to stop, rest for a moment, the pain disappeared, you can also continue to walk; symptoms repeated, to a period of time to stop several times to rest. This symptom is often thought of as old age and leg inconvenience, but in fact it is a sign of atherosclerosis of the lower extremities, which in medical terms is called intermittent claudication. Lower extremity atherosclerosis is part of systemic atherosclerosis. When lipid components in the blood are deposited under the intima of the arteries leading to the lower extremities, or when smooth muscle cells under the intima proliferate, causing the intima to protrude into the lumen, the lumen is narrowed and blood flow to the lower extremities is reduced. As the lesion progresses, the lumen becomes narrower and narrower, and when the blood supply cannot meet the demand for oxygen and nutrients during the movement of the limb, the corresponding symptoms will appear. Initially, the limb becomes cold and numb, and the muscles of the lower extremity have an increased need for oxygen when walking. When the activity stops, the metabolic wastes are removed by the blood flow and the pain disappears, a symptom that is repeated. The distance between the start of walking and the onset of pain forcing a stop is called the claudication distance. As the lesion progresses the claudication distance gradually decreases. When stenosis or occlusion of the arterial trunk occurs, local hypotension in the distal artery releases vasoactive substances, resulting in dilation of the small collateral arteries, which maintain nutritive blood flow through compensatory microvascular dilation. The lesion progresses further, and when the collateral compensation is also insufficient to maintain the needs of the limb, the part of the toe with the poorest blood supply experiences pain around the clock, called resting pain. Eventually gangrene develops in the extremity. Symptoms of intermittent claudication should be seen at the earliest possible time after they occur. Depending on the patient’s condition, the doctor may recommend ultrasonography, arterial segmental manometry, magnetic resonance angiography, or angiography, as he or she may find pulselessness in one or both limbs and cold, purple, or pale extremities. Ultrasound is less expensive, but its accuracy depends on the operator’s experience and does not provide images familiar to the clinician; segmental manometry can be used for rough characterization and localization of the condition; MRI can provide an overall image of the artery, but its accuracy depends on the function of the MRI machine and the operator’s experience; the most accurate method is angiography, which is an invasive test. The most accurate method is angiography, which is an invasive test and requires hospitalization. During the imaging procedure, an arterial puncture is performed from the groin or upper extremity, a catheter is inserted, and the catheter is placed in the artery to inject the contrast agent. The treatment of lower extremity atherosclerosis includes: conservative medical treatment and surgical treatment. Internal treatment is suitable for patients with mild cases or those who cannot tolerate surgery, including smoking cessation, warmth, appropriate exercise, hyperbaric oxygen therapy, and various vasodilators, anticoagulants, and blood-vitalizing drugs. Surgical treatment includes both interventional treatment and surgical treatment. Interventional treatment is a minimally invasive treatment, in which a catheter is introduced through arterial puncture under local anesthesia and the stenosis is dilated or stented, with the advantage that it is less invasive and the patient recovers quickly, and it is suitable for larger vessels. Interventional treatment is good but expensive and not suitable for patients with long vascular lesions. Surgical treatment varies from person to person, and the two main types are sclerosing endothelial debridement and bypass grafting. If the lesion is limited, local sclerosing endothelial debridement can be used; otherwise, bypass surgery is required. An autologous saphenous vein or an artificial vessel is used to anastomose with a normal artery at each end of the stenotic occluded segment, thus supplying blood to the distal limb across the stenotic segment. Compared to interventional treatment, bypass surgery is more invasive and usually requires general or semi-body anesthesia, with bed rest for 5-7 days and stitches removed in 2 weeks. Whether interventional or surgical treatment, there is a possibility of thrombosis and re-embolization after surgery, so anticoagulation or antiplatelet therapy should be continued. Lower extremity atherosclerosis is usually a segmental lesion, and most of them have conditions for bypass, but if the blockage is too long and secondary thrombosis occurs in the distal vessels, the opportunity for bypass will be lost, which will eventually lead to amputation. Therefore, early diagnosis and early treatment are crucial.