Diabetic foot is a lesion that causes destruction of the foot or lower extremity tissue in diabetic patients due to factors such as diabetic vasculopathy and/or neuropathy and infection. It is a serious diabetic complication that threatens diabetic patients and causes serious impact and burden to patients, their families and society.
Disease definition
WHO definition: foot infection, ulceration and/or deep tissue destruction associated with local nerve abnormalities and peripheral vascular lesions in the distal lower extremity.
Epidemiology
(i) International
In foreign countries, 85% of amputations in diabetes originate from foot ulcers, and the amputation rate is 25 times higher than that in non-diabetes (5/10,000-180/10,000). 47% of diabetic inpatients are hospitalized due to diabetic foot.
(II) The situation in China
There is a lack of complete national data.
1996 – 2000 diabetic foot accounted for 2.45% of hospitalized diabetic patients, amputation rate of 14%; 304 hospital retrospective analysis of the past 10 years in 2306 hospitalized patients, diabetic foot accounted for 2.5%; Tianjin Medical University General Hospital statistics show that: diabetic foot accounted for 2.24% of outpatient, 8.57% of hospitalized, amputation rate of 17.31%; international scope data show that According to international data, 15% of diabetic patients have at least one foot ulcer in their lifetime, and in China, 10% of diabetic patients have foot ulcers.
The causes of morbidity include.
①Neuropathy: sensory, motor and autonomic neuropathy;
②Vascular lesions;
(iii) Circulatory disorders;
④Immune disorders;
⑤ Decrease in insulin growth factor-1 (IGF-1), which promotes skin growth, in the skin. Among them, neurological and vascular lesions are the main ones.
Clinical manifestations
The signs and symptoms of diabetic foot vary depending on the course of the disease and the severity of the lesion. In mild cases, there is only minimal foot pain and skin surface ulcers; 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, and even whole foot gangrene may occur.
Grading.
Grade 1: Skin surface ulcers on the foot without signs of infection. The ulcers tend to develop 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: Ischemic ulceration with gangrene, 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.
Predisposing factors
(1) Scratching of the skin between the toes or on the foot due to itching;
(ii) Ulceration, ruptured blisters, burns;
③Injuries, collision injuries and new shoe abrasions, etc.
Risk factors
Diabetic patients over 40 years old; diabetic patients over 10 years old; male; smokers, smoking can aggravate circulatory disorders; loss of peripheral nerve sensation and diminished or absent peripheral arterial pulsation; foot deformities, such as high arches and claw toes; history of foot ulcers or amputations; uncontrolled blood sugar; combined cardiovascular, renal and fundus pathologies; combined peripheral neurological and vascular pathologies; elderly, especially those who live alone; self-protection Inadequate; little knowledge of diabetes mellitus; decreased foot sensation; inappropriate shoe size, nail and foot skin lesions.
Types of manifestations
① Foot ulcers;
② foot gangrene: including dry, wet and mixed;
(iii) foot ischemia.
Causes of foot ulcers: neuropathy is an important cause 78%; triad of neuropathy, deformity and trauma 63%; ischemia 35%; 80% of ulcers can be prevented.
Disease diagnosis
(A) Medical history taking
To understand the duration of the disease, treatment and other complications in diabetic patients, identify the cause, duration, degree and progression of ulcers in the foot.
(II) Physical examination
Pay attention to the appearance, extent, depth, temperature and odor of the ulcerated surface, and also determine whether the foot has deformity, swelling, soft tissue infection or osteomyelitis. Check the condition of the patient’s contralateral limb and the suitability of shoes and socks.
(C) Auxiliary examination
1.Nervous system examination
The purpose is to understand whether the patient still has protective nerve sensation. The most simple and commonly used method is to use a special 10 gram nylon wire, one end touches the patient’s big toe, heel and the outside of the front sole of the foot, press the other end of the nylon wire with your hand and apply gentle pressure, just so that the nylon wire bends, and the patient can feel the nylon wire on the bottom of the foot or toes at this time, then it is normal, otherwise it is abnormal. There is also a tuning fork to check the patient’s sensation of vibration.
2.Skin temperature check
Diabetic foot examination method
Check the skin sensation to temperature changes, and respond to whether the nerve function is damaged. There are qualitative and quantitative tests. Qualitative is to place a tuning fork or a thin stainless steel stick in a cup of warm water, remove it and measure the sensation of the skin in different parts of the patient, while comparing with normal people. Quantitative examination requires the use of instruments.
3.Pressure measurement
By measuring the pressure in different parts of the foot, we can understand whether the patient has abnormal pressure in the foot. Usually the subject is made to stand on a plate with a multi-point pressure sensitive device, which is imaged by scanning and analyzed on a computer.
4.Peripheral vascular examination
The simplest method is to use the hand to touch the pulsation of the dorsal foot or posterior tibial artery to understand the foot macrovascular pathology, and the disappearance of fluctuation suggests a serious macrovascular pathology, which requires the next step of examination.
(1) Vascular ultrasonography: the examination is used to clarify whether there is stenosis or occlusion of blood vessels.
(2) Ankle artery-brachial artery blood pressure ratio: reflecting the blood pressure and vascular status of the lower limbs, the normal value is 1.0-1.4; 0.9 is mild ischemia, 0.5~0.7 is moderate ischemia, and 0.5 is severe ischemia. Patients with severe ischemia are prone to gangrene of the lower extremities (or toes).
(3) Angiography: to understand the degree and site of lower limb vascular occlusion, to provide a basis for amputation plane or vascular bypass surgery.
(4) Transdermal oxygen partial pressure measurement: reflect the state of microcirculation and also the blood supply status of peripheral arteries.
(5) Blood rheological examination: whole blood viscosity, plasma specific viscosity, whole blood reduction viscosity; erythrocyte aggregation index, erythrocyte stiffness index; plasma fibrinogen content measurement.
5. Examination of ulcer co-infection
Probe the ulcer suspected of infection, such as the discovery of sinus tracts, probe and bone tissue, to consider osteomyelitis; while using the probe to take a specimen of the deep ulcer for bacterial culture, to increase the specificity of the culture of infected bacteria. Deep infection or bone lesions can also be identified by X-ray plain film, isotope scan or magnetic resonance examination.
6. Examination of Charcot arthropathy
Charcot arthropathy may be complicated by a long history of diabetes mellitus. Specialist examination is required to confirm the diagnosis.
Disease treatment
1.Medical treatment.
①Control hyperglycemia;
②Improve microcirculation;
③Improve nerve function;
④Lower blood lipids;
⑤ local debridement;
⑥Apply effective antibacterial agent;
(7) Combine with hyperbaric oxygen and traditional Chinese medicine, if possible.
2.Surgical treatment
(1) Local treatment of trauma
(2) Revascularization
(3)Amputation
3.Stem cell transplantation
Stem cell transplantation is a new treatment method for lower limb vascular lesions and diabetic foot developed in recent years, which has been discussed by several scholars at home and abroad and has made some progress.
4.The special treatment mode of pain department – lumbar sympathetic ganglion chemical resection
For patients with diabetic foot pain, lumbar sympathetic ganglion chemical excision can fully relieve lower limb pain, improve microcirculation of the affected lower limb, establish collateral circulation, improve nutritional status, promote local ulcer healing, and terminate or delay the progression of diabetic foot.