The diabetic foot is one of the most serious complications of diabetes, but its pathology is also a gradual process, and the signs and symptoms of the diabetic foot vary at different times depending on the course of the disease and the severity of the lesion. The diabetic foot is a common chronic complication in diabetic patients, and its high incidence and disability rate have become an important public health problem, so it is especially important to prevent and treat the diabetic foot in its early stages. The clinical features of diabetic foot are early numbness, pain, chill and/or intermittent sloping, resting pain in the extremities, and continued development of blackened skin, tissue ulceration, infection, and gangrene in the distal lower extremities. In moderate cases, deep penetrating ulcers combined with soft tissue inflammation may occur. In severe cases, the ulcers are combined with soft tissue abscesses, bone histopathy, limited gangrene of the toes, heel or forefoot dorsum, or even gangrene of the whole foot may occur. The Wagner method of grading diabetic foot is widely accepted and is based on the severity of the patient’s condition. 0 to 5: Grade 0 refers to the presence of risk factors for ulcers, including: ① peripheral neuropathy, autonomic neuropathy; ② peripheral vascular disease; ③ previous history of foot ulcers; ④ foot deformities, such as eagle claw foot, Charcot foot; ⑤ combined with foot ulcers. Charcot foot; ⑤ combined with callus or “corns”; ⑥ blindness or severe vision loss; ⑦ combined with renal pathology, especially chronic renal failure; ⑧ elderly people or people who cannot observe their own feet, especially those who live alone; ⑨ people with sensory loss; ⑩ people who lack knowledge of diabetes. Diabetic foot also known as diabetes combined with extremity gangrene Wagner method of classification table: (mainly based on clinical performance grading.) Grade 0: generally refers to grade 0 to 1, also known as early diabetic foot. The main manifestations are limited to sensory abnormalities or superficial ulcers. Grade 1: Superficial ulcers on the skin surface of the foot, but no manifestation of infection. Superficial ulcers tend to occur on prominent areas of the foot, such as the heel, foot or bottom of the foot, and the ulcers are mostly surrounded by calluses. Grade 2: Exhibits deeper penetrating ulcers, often combined with soft tissue infection, but without osteomyelitis or deep abscesses. Grade 3: Deep ulcers often affect bone tissue and have deep abscesses or osteomyelitis. Grade 4: manifests as a limited ischemic ulcer with gangrene (toe, heel, and forefoot dorsum), often combined with neuropathy without severe pain, and the surface of the necrotic tissue may be infected. Grade 5: Gangrene affecting the entire foot, with extensive and severe lesions, some of which develop rapidly.