With the aging of our population, the incidence of diabetes is on the rise. The number of people with diabetes in China has reached 40 million, and about 20 million others with increased blood glucose are untreated. The seriousness of diabetes is not in itself, but in its complications. According to statistics, the incidence of gangrene of the extremities is 53 times higher in men with diabetes than in non-diabetic patients and 71 times higher than in women. Clinical manifestations of diabetic foot: It has common features of general limb ischemic diseases, such as cold fear, pale skin, reduced blood flow, intermittent claudication, and nutritional disorders. The unique features are: firstly, the clinical manifestations of combined diabetes and multi-organ vascular complications; secondly, the characteristic gangrene occurs at a later stage.