In the cold winter, people are very sensitive to the climate, especially the elderly. In winter, although the sun shines from time to time, the temperature is still very low, especially in the morning and evening the weather is unusually cold, stay outdoors is very easy to be attacked by cold air, the elderly because the body immune system is reduced, used to sit or lie still, the lower limbs under pressure, stop activities when the lower limbs will feel very cold, there will be numbness and other conditions. Therefore, to prevent diseases in winter, the elderly should focus on protecting the lower limbs. Lower extremity stroke. 60 years of age or older is a high risk, the lower extremity is the farthest from the heart, the local blood flow is relatively slow, lower extremity stroke, a common disease in the elderly is most likely to quietly visit in winter. If an elderly person feels heavy and uncomfortable in the lower extremities after exertion, cold under the knees, numbness in the lower legs, or thickened toenails in the feet, it may be a lower extremity stroke. “Lower extremity stroke is an acute lower extremity artery occlusion caused by lower extremity atherosclerosis, which not only affects the extremities, but also involves the heart, brain, kidneys and internal organs. If the condition worsens, blood clots may form within a short period of time, and the condition may worsen, resulting in the loss of a limb. Lower limb stroke is a manifestation of systemic atherosclerosis, and the incidence of lower limb stroke in people over 60 years old is as high as 79.9%. Doctors’ advice: high age, hypertension, diabetes, hyperlipidemia, etc. are high risk factors for atherosclerosis. Such patients should eat less greasy food, exercise in moderation, eat more vegetables and fruits, take small doses of medication if necessary, and go to the hospital regularly to assess the arterial patency of the limbs. If early symptoms such as sleepiness, discomfort and intermittent claudication of lower limbs after exertion appear, they should be examined immediately. Lower limb venous thrombosis should be prevented at three levels. The cold brings a lot of health risks to the elderly. As the weather gets colder, the incidence of venous thrombosis in the lower extremities of people who are sitting or lying down increases compared to normal temperature, so doctors remind people to do a good job of tertiary prevention. Lower limb vein thrombosis mostly occurs in the left lower limb, the lower limb swelling, thickening, pain, the onset is very rapid. Its formation process is very much like the process of atomic bomb explosion, exogenous and endogenous coagulation system acts one after another, a small piece of attached wall thrombus will rapidly expand and spread in the venous cavity, eventually making the lower limbs thicken, painful and even pale, bruised and blistered, and even a terrible complication. Doctor’s advice: this disease prevention is divided into three levels. Primary prevention, to prevent long time limb inactivity and trauma; secondary prevention, prevention of high-risk groups, timely treatment of lower limb phlebitis, varicose veins; tertiary prevention, the occurrence of limb vein thrombosis, to timely surgery to remove the embolism or thrombolysis. Once deep vein thrombosis occurs in the lower limbs, early treatment is needed. If there is sudden pain and swelling in single lower limb, it should not be misdiagnosed and mistreated as arthritis or lumbar spondylosis.