1.Definition
A foot disorder caused by loss of sensation due to neuropathy or loss of mobility due to ischemia, combined with infection in diabetic patients. The most common consequence is chronic ulceration, and the most serious end is amputation.
2.Examination of diabetic foot
2.1 Routine examination of sensation or dorsalis pedis artery pulsation is the most important way to detect that the foot is at risk of ulceration. In the community, sensation is best measured with a 5.07/10 gram Semmes Weinstein single nylon wire. The single nylon wire test is a simple and inexpensive method of sensory testing. When a force of 10 grams is applied, it bends. If the patient cannot feel this pressure, it is assumed that there is sensory loss in this foot.
2.2 Electrophysiological examination: The application of nerve conduction velocity electromyography can detect 90% of diabetic peripheral neuropathy early, and the patient’s motor and sensory nerve conduction velocity is generally slowed down by about 15%-30%.
2.3 X-ray examination: it can detect osteoporosis or destruction, osteomyelitis and bone and joint lesions, etc.
2.4 Color ultrasound: non-invasive, screening for the presence or absence of stenosis or occlusion of lower extremity arteries.
2.5 Lower limb arteriography: the gold standard for diagnosing the presence or absence of stenosis or occlusion of lower limb arteries.
3.Clinical manifestations of diabetic foot
The clinical manifestations of diabetic foot patients are related to five aspects of lesions: neuropathy, vascular lesions, biomechanical abnormalities, lower limb ulcer formation and infection.
3.1 General manifestations: due to neuropathy, the skin of the affected limb is dry and sweatless; tingling, burning pain, numbness, dullness or loss of sensation at the extremity, sock-like changes, and the feeling of stepping on cotton wool; due to malnutrition at the extremity, muscle atrophy, the flexor and extensor muscles lose the normal balance of traction tension, causing the bones to sink causing the interphalangeal joints to bend, forming bowed feet, mallet toes, chicken claw toes and other foot deformities. When the patient’s bone joints and surrounding soft tissues are strained, the patient continues to walk easily resulting in bone joint and ligament damage, causing multiple fractures and ligament rupture, forming Charcot joints (Charcot). x-ray examination mostly has bone destruction, and some small bone fragments detach from the periosteum causing dead bone affecting gangrene healing.
3.2 Manifestations of ischemia: common skin dystrophy muscle atrophy, dry skin with poor elasticity, detachment of hair, decreased skin temperature, pigmentation, weakened or absent arterial pulsations at the extremities, and vascular murmurs can be heard at the narrowed vessels. The most typical symptoms are intermittent claudication, painful rest, and difficulty in squatting and standing up. When the patient has a break in the skin of the affected limb or spontaneous blistering after being infected, ulcers, gangrene or necrosis are formed.
3.3 Diabetic foot ulcers can be divided into neurological ulcers, ischemic ulcers and mixed ulcers according to the nature of the lesion.
Neuropathic ulcers: neuropathy plays a major role in the etiology and has good blood circulation. This foot is usually warm, numb, and dry, with little pain and good fluctuation of the arteries in the foot. A foot with concurrent neuropathy can have two consequences: neuropathic ulcers (mainly on the sole) and neuropathic arthropathy (Charcot joint).
Foot ulcers due to ischemia alone, without neuropathy, are rare.
Neuro-ischemic ulcers these patients have both peripheral neuropathy and peripheral vasculopathy. The dorsalis pedis artery fluctuations are absent. The foot is cold in these patients and may be associated with pain at rest and ulceration and gangrene at the foot margin.
Foot ulcers occur mostly in the forefoot plantar, often due to repeated mechanical pressure, due to the loss of protective sensation caused by peripheral neuropathy, the patient can not feel this abnormal pressure change, can not take some protective measures, the occurrence of ulcers complicated by infection, ulcers are not easy to heal, and finally gangrene occurs.
4.Diabetic foot grading
The classic grading method is the Wagner grading method.
Grade 0: foot with the risk of foot ulcers, no open lesions on the skin.
Grade 1: surface ulcers, no clinical infection.
Grade 2: deeper ulcerated infected lesions, often combined with soft tissue inflammation, without abscesses or infection of the bone.
Grade 3: deep infection with bone histopathy or abscess.
Grade 4: Bone defect with partial gangrene of the toe and foot.
Grade 5: Major or total gangrene of the foot.
5.Treatment
Interventional treatment: Low-pressure balloon dilation is given to patients with significant narrowing or occlusion of the lower extremity arteries causing lower extremity ischemia.
6.Prevention
Diabetic foot occurs very importantly due to limb ischemia, neuropathy, infection and triggering factors, therefore, prevention should be the main focus in treatment, prevention and treatment for the cause
6.1 Active treatment of diabetes and strict control of hyperglycemia.
6.2 Rational distribution of diet and strict control of hyperlipidemia and various factors leading to early atherosclerosis.
6.3 Improve blood circulation in the extremities and exercise appropriately, such as insisting on calf and foot exercises for 30-60 minutes every day. Prohibit smoking, as smoking can cause vasospasm of the limb and aggravate tissue ischemia.
6.4 Pay attention to foot hygiene and cleanliness, wash feet with warm water every night to keep the skin soft and feet warm; at the same time, pay attention to not overheating the foot washing water to prevent burns. Do not soak the feet for the existing ulcerated wounds.
6.5 Treatment of calluses and corns on both feet, shoes and socks should be clean and loose, soft and well-fitting, breathable, and should not be walked barefoot.
6.6 Prevent foot trauma and frostbite. Frequently check the foot end for risk factors, such as whether there are lacerations, insect bites, blisters, redness, swelling, discoloration, feeling whether there is a change in temperature, once found, must be properly treated.
6.7 To prevent infection, those who have tinea pedis and secondary infection should apply 0.2 parts per thousand of potassium permanganate water solution to wash their feet three times a day and ask a dermatologist for early consultation and treatment. Small wounds should be seen by a doctor promptly and should not be treated by yourself.
6.8 Toenail trimming should not be too short, so as not to damage the nail groove caused by secondary infection.
6.9 Seek medical attention when the skin of the affected foot becomes red, painful and swollen. Once diabetic foot gangrene occurs, it should be treated formally in hospital as early as possible.
6.10 Adhere to a diabetic diet and give a low-cholesterol, light and easy-to-digest diet with plenty of green leafy vegetables.
6.11 Prohibit smoking and drinking alcohol to prevent vasoconstriction and affect blood supply.