Diabetic foot syndrome
Diabetic foot syndrome is one of the complications of diabetes mellitus, along with diabetic ophthalmopathy, nephropathy, etc., which is a pathological condition resulting from damage to the peripheral nervous system, arterial and microvasculature, manifested by purulent-necrotic, ulcerative processes and damage to the bones and joints of the foot … It arises as a result of a violation of carbohydrate metabolism in the body and the development of diabetes mellitus, in the absence of an adequate correction of this condition.
According to medical statistics, the prevalence of diabetic foot syndrome among patients with diabetes mellitus is about 5-10%. A significant proportion of all non-traumatic lower limb amputations occur in patients with diabetic foot syndrome (about 60%).
Diabetic foot syndrome: classification
Depending on the cause and mechanism of development of the pathological process, there are three main forms of diabetic foot syndrome :
1. The neuropathic form of diabetic foot syndrome is the most frequently detected form (in 70% of cases), which can occur with a violation of the integrity of the bone tissue and joints of the feet (with osteoarthropathy) and without osteoarthropathy.
2. Neuroischemic form – associated with damage to both peripheral nerves and vessels of the microvasculature. It occurs in 15-20% of cases of diabetic foot syndrome.
3. Ischemic form – one of the variants of diabetic angiopathy, in which the main blood vessels are involved in the process. It is found in 5-7% of patients.
There is also a combined classification that takes into account the degree of damage to the tissues of the foot in conjunction with the cause that caused the pathological process. According to this classification, there are 5 stages of development of diabetic foot syndrome :
– Stage 0 of diabetic foot syndrome – violations of the integrity of the skin of the foot are not detected, but there are signs that increase the risk of developing diabetic foot syndrome, such as cracks, corns, calluses, pronounced deformities, decreased sensitivity of the feet.
– Stage 1 . There are two types of this stage: 1A – characterized by the presence of a superficial ulcer without signs of infection, while the blood flow in the foot is not changed; 1B – superficial ulcer on the foot against the background of decreased blood supply.
– Stage 2 . 2A – characterized by the presence of an ulcer defect in which soft tissues are involved, against the background of normal blood supply; 2B – an ulcer involving soft tissues in the process, associated with limb ischemia.
– Stage 3 . Bone tissue and tendons are involved in the ulcerative process. 3A – no signs of deep infection; 3B – with signs of deep infection.
– Stage 4 . It manifests itself in the form of gangrenous lesions of the foot with reduced main blood flow.
Causes and mechanism of development of diabetic foot syndrome
The factors leading to the development of a diabetic foot in patients with diabetes mellitus include injuries, neuropathies, chronic arterial and venous insufficiency of the lower extremities, systemic diseases of the connective tissue, vasculitis, fungal infections, erysipelas, pyoderma, allergic reactions to medications, vitamin deficiencies, etc.
In order for an ulcer to form on the foot of a patient with diabetes mellitus, there must be a damaging effect on the foot from the outside. Fertile soil for the formation of an ulcer defect occurs due to dry skin, reduced sensitivity due to sensory neuropathy, as well as impaired blood circulation. Trauma can be acute – thermal burn or mechanical damage with a sharp object, or chronic – when for a long time the patient wears shoes that compress certain areas of the foot, which leads either to hyperkeratosis (keratinization) with the subsequent formation of hematomas, or to calluses, which are damaged, expose the wound surface. And in fact, and in another case, the inevitable outcome is the formation of a peptic ulcer.
The mechanism of development of the ischemic form of the diabetic foot is somewhat different. Due to impaired blood circulation, the lower limbs of patients with diabetes mellitus are prone to edema, especially during physical exertion. These areas on the feet are squeezed by shoes, resulting in the formation of extensive areas of ischemia, which are subsequently subject to necrotic processes.
In the formation of diabetic osteoarthropathy (Charcot’s foot), the trigger is an increase in blood supply to the osteoarticular apparatus of the foot, which leads to destructive changes in the bone tissue. Moreover, due to a decrease in pain sensitivity, the patient does not feel these changes for a long period.
There are a number of factors that favor the development of diabetic foot syndrome with peptic ulcer defect in persons with diabetes mellitus. These are primarily elderly people, with already identified retinopathy and nephropathy, suffering from heart or venous insufficiency. The risk group also includes people with overweight, immunodeficiency states, leading an asocial lifestyle, lonely.
In a word, the mechanisms of development and the causes of the onset of diabetic foot syndrome are diverse. It is only known that late complications of diabetes mellitus, such as macro- and microangiopathies, polyneuropathies in combination with external and internal factors lead to the development of one form or another of diabetic foot syndrome.
Signs of a diabetic foot
The neuropathic form of diabetic foot syndrome develops more often than others. Ulcerative defects are located in the zones of the sole of the foot, which account for the maximum pressure during walking. Ulcers are usually painless, with marked hyperkeratosis along the edge of the defect. Patients present with complaints that are characteristic of peripheral polyneuropathy, namely, a decrease in temperature, pain, vibration sensitivity, a feeling of numbness, tingling or burning in the fingers, pain at night.
Examination of the feet reveals a specific deformity of the feet, expansion of the dorsal veins of the foot with preserved pulsation of the peripheral arteries. The skin of the legs is dry, warm, cracks and areas of excessive keratinization may be noted on the feet.
The ischemic form of diabetic foot syndrome occurs as a result of peripheral vascular pathology in the form of obliterating atherosclerosis of the arteries of the lower extremities or Meneberg’s sclerosis. This form of diabetic foot is observed more often in patients over 45 years old, with concomitant pathology of the cardiovascular system and cerebral vessels (ischemic heart disease, arterial hypertension, etc.). A typical site of localization of ulcers is the heel, interdigital spaces and fingertips. The ulcers are painful, surrounded by thinned skin, dry, necrotic areas in the form of a scab form on the ulcers.
On examination, the pallor of the skin of the lower extremities is revealed, they are cold to the touch. Arterial pulsation is absent or very weak. No bone changes are observed. Tactile, temperature and vibration sensitivity are preserved. Patients may have intermittent claudication that occurs when climbing stairs or walking vigorously.
The development of osteoarthropathy in diabetic foot syndrome is determined by the following symptoms:
– in the acute stage: redness, an increase in temperature in the area with an ulcer defect by more than 2 degrees, edema, pain, on the roentgenogram – a picture of osteoporosis;
– in the chronic stage: destructive changes in the bones of the foot on the roentgenogram, the formation of ulcers in places of excessive pressure, as well as deformity of the foot with the development of collapse of the arch of the foot.
Infection of the ulcer can lead to a serious condition leading to the amputation of the limb. Most often, infection of ulcerative defects occurs due to the attachment of a polymicrobial infection, which includes groups of aerobic and anaerobic gram-positive and gram-negative microorganisms. The defeat of the wound surface by infectious agents may not threaten the limb, pose a threat to the limb and threaten life.
The penetration of infection within the soft tissues does not threaten the limb – cellulitis up to two centimeters deep, characterized by edema, local redness and an increase in local temperature. If painful sensations join, one should suspect the involvement of the deep tissues of the foot in the process, as a result of which diabetic gangrene develops. In this case, tissues are affected to a depth of more than 2 cm – cellulitis, fasciitis, abscess or phlegmon of the feet and osteomyelitis. These infections pose a threat of limb loss, so such patients need urgent hospitalization.
Diagnostics of the diabetic foot syndrome
The diagnosis is made on the basis of anamnesis, physical, instrumental and laboratory research methods of the patient. Anamnestic data can allow timely identification of the factor of foot trauma in order to eliminate the cause of ulceration. Patients are recommended to pass a general and biochemical blood test, a blood and urine test for glucose, a coagulogram, and when an infection is attached, a bacteriological examination of exudate from the wound.
Examination of the patient reveals the nature and form of the lesion, as well as the stage of the diabetic foot. With the help of instrumental research methods, tactile, pain and temperature sensitivity are revealed. To determine the state of patency of the arteries of the lower extremities, the definition of the ankle-brachial index is used, determining the ratio of systolic pressure in the knee artery and brachial artery. If this figure is below 0.9, stenosis of the arteries of the lower extremities can be suspected. Transcutaneous oximetry is also used – a method that allows you to determine the state of tissue blood flow. Indicators below 30 mm Hg. indicate the presence of a lack of blood supply in the tissues of the feet.
If necessary, differential diagnosis is consulted by vascular surgeons, endocrinologists and other narrow specialists.
Treatment of diabetic foot syndrome
Since diabetic foot syndrome, depending on the form and stage, can pose a threat to a person’s life, in certain cases, patients need hospitalization to monitor the condition and course of the pathological process, and to carry out appropriate therapeutic manipulations. Hospitalization of patients with diabetic foot syndrome is recommended in the presence of symptoms of an infectious lesion of ulcerative defects of moderate and severe severity, with gangrene of a toe or one of the zones of the foot, with signs of acute arterial or venous insufficiency, in the acute phase of neuroosteoarthropathy, as well as in ulcerative defects 2, 3 , 4 degrees.
Depending on the severity of the condition and the nature of the damage to the tissues of the foot, the treatment of diabetic foot syndrome can be conservative and surgical. Drug therapy involves, first of all, the correction of the underlying disease – diabetes mellitus. In addition, therapy is needed to maintain normal blood pressure levels. Since one of the causative factors of the disease is a violation of the blood supply to the feet due to atherosclerotic vascular changes, adequate therapy is needed to lower blood cholesterol.
If signs that are characteristic of infected wounds are found, antibiotic therapy is initiated. Moreover, the general signs accompanying the addition of infection (fever, general intoxication) may be absent in patients due to a decrease in the immune response. Therefore, antibiotics are prescribed on the basis of the local manifestation of infectious inflammation, namely, with redness, edema, hyperthermia of the wound area, the presence of purulent discharge, an unpleasant odor, granular growths, etc. The choice of the drug is carried out based on the data of bacteriological analysis and determination of the sensitivity of microorganisms to antibiotics.
If the process is shallow, it is recommended to take antibiotics in tablets, and it is carried out on an outpatient basis. In severe wound infections (phlegmon, gangrene, sepsis), antibacterial drugs are administered intramuscularly or intravenously in a hospital, combining this process with regular wound care.
If a purulent process develops on the foot, accompanied by tissue necrosis, they resort to surgical treatment of the wound, which involves the radical removal of all necrotic tissue, drainage of the wound, followed by plastic surgery. When diabetic foot syndrome occurs as a result of stenosis of the vessels supplying the foot, revascularization is required using endovascular methods (angioplasty with stenting), or by performing prosthetics of large arteries or distal bypass grafting. With the development of gangrene, they resort to amputation of the limb above the site of localization of the process.
Prevention of diabetic foot syndrome
To prevent the development of a diabetic foot, patients with diabetes should constantly monitor their blood glucose levels, follow a diet and take regularly the necessary medications, inspect their feet daily for signs that may contribute to the development of mechanical damage, and follow the rules of foot care.
Foot care for diabetic patients should consist of daily washing of the feet with gentle wiping, daily change of socks and stockings, examination of the feet for scratches, cuts, corns, calluses. It is very important to choose the right shoes for yourself, best of all – orthopedic, lubricate your feet at night with a fat cream containing sea buckthorn oil. When trimming nails, be as careful as possible with the cutting tool. If the skin is damaged, it is not recommended to treat the wound with a solution of iodine or brilliant green, as they dry out the skin, which can lead to dehiscence of the edges of the damage. It is best to carry out the treatment with chlorhexidine or hydrogen peroxide.
The choice of footwear should also be approached thoroughly. The onam should be seamless, soft, comfortable, with a thick insole. Orthopedic shoes can reduce the likelihood of developing diabetic foot syndrome several times.
At least once a year, it is necessary to examine, palpate and assess the sensitivity of the feet by an endocrinologist.