1, no limb infection occurred: daily before washing feet test the water temperature with your hands, wash feet carefully with <40< span=""> ℃ warm water, wipe clean with a light-colored, soft, absorbent dry towel, dry skin wipe lubricating lotion or nutritional cream, toe seam wide as clean as possible, no moisture. Check the feet carefully every day and massage the feet and legs or exercise appropriately, twice a day for 30 min. trim the toenails regularly so that they are not too long or too short, and ask family members or doctors and nurses to help if you are visually impaired. Do not walk barefoot or in shoes with exposed toes to avoid damaging the skin of the feet. Wear light-colored, soft, loose cotton pants. Wash socks daily. Choose flat-heeled, thick-soled shoes with wide tips, non-extruding toes and breathable uppers. 2.Infection or gangrene has occurred: different treatment methods are used for different stages of the disease. Cellulitis stage: local redness, swollen lymph nodes, fever, general discomfort. Treatment principles: ① most cellulitis can be cured by local care and oral antibiotics; ② severe cellulitis requires intravenous drip antibiotics or even emergency surgical treatment. Ulcerative stage: blistering, keratinization, superficial to full lesions, deep lesions involving tendons, bones or joints. Treatment principles: ① wound care, diligent dressing changes; ② application of antibiotics when there are signs of infection; ③ clearing of keratinized edges or necrotic parts. Abscess stage: local skin blister to deep abscess on the bottom of the foot, involving tendons or superficial tissues. Treatment principles: ① necrotic and infected tissue clearance; ② culture followed by sensitive antibiotic treatment; ③ reconstructive surgery. Osteomyelitis stage: limited osteomyelitis (dead bone) or diffuse osteomyelitis. Treatment principles: ① necrotic and infected tissue debridement; ② culture followed by sensitive antibiotic therapy; ③ reconstructive surgery. Stage of gangrene: dry, wet, gas gangrene or necrotizing fasciitis. Principles of treatment: All gangrenous tissue must be removed, followed by reconstruction.