Neuropathic leg swelling

The diabetic foot syndrome is complexa complex of anatomical and functional changes, which occurs in different forms in 30-80% of patients with diabetes mellitus. Amputations of the lower limbs in this group of patients are 15 times more likely than in the rest of the population. According to the data of a number of authors, from 50 to 70% of the total number of all performed amputations of the lower extremities falls on the proportion of patients with diabetes mellitus. In 1993, the Russian Federation produced about 12,000 amputations of lower extremities at various levels in patients with diabetes mellitus.

In the pathogenesis of the development of the diabetic foot syndrome, the leading place is occupied by three main factors:

defeat of arteries of lower extremities
The last factor, as a rule, isassociated with the first two. Based on the prevalence of neuropathic changes or violations of peripheral blood flow, there are two main clinical forms of the diabetic foot syndrome:

neuropathic (Fig. 5)
ischemic (Fig.6)
Fig.5 Neuropathic form of diabetic foot with trophic infected ulcer

Fig.6 Gangrene of the lower extremity due to peripheral vascular injury in a patient with diabetes mellitus (ischemic form)

Along with the two main forms of the defeat of the lower extremities in diabetes mellitus, there is also a third:

mixed (neuro-ischemic)
With a neuropathic form, there is a lesionsomatic and autonomic nervous system with intact arterial segments of the lower limbs. Neuropathy can lead to the following three types of lesions of the feet:

Neuropathic ulcers
osteoarthropathy (with the subsequent development of the joint of Charcot)
Neuropathic edema
Ischemic form develops as a consequenceatherosclerotic lesions of arteries of the lower extremities, which leads to disruption of the main blood flow. Neuropathic changes may also occur. However, a decrease or a complete absence of pulsation on the arteries of the feet and shins, cold extremities with palpation, pain symptoms, and the characteristic localization of ulcerative defects of the type of acral necrosis make it possible to differentiate the neuropathic and mixed (neuro-ischemic) forms of foot damage.

Neuropathic form of diabetic foot syndrome

Neuropathic defect occurs on sitesThe feet experiencing the greatest pressure, especially often on the plantar surface and in the interdigital spaces. Long-flowing sensorimotor neuropathy leads to deformation of the foot, which contributes to the redistribution and excessive increase of pressure on its individual areas, for example, in the projection of the heads of metatarsal bones. In these places there is a thickening of the skin, the formation of hyperkeratoses, which have a rather high density. Constant pressure on these areas leads to inflammatory autolysis of the underlying soft tissues, the formation of a ulcerative defect. In this case, the patient may not notice the changes occurring due to reduced pain sensitivity.

Very often the formation of ulcerative lesionsoccurs because of improper shoe selection. As mentioned above, sensorimotor neuropathy leads to a characteristic deformation of the foot. On the other hand, very often there is a presence of a neuropathic edema (for more details, see the next page). Thus, the patient's foot changes not only the shape, but also the dimensions. At the same time, shoes are selected by patients based on knowledge of their previous sizes, and one or two measurements are taken into account. Reduced sensitivity does not allow the patient to detect the inconvenience of new shoes in a timely manner and, as a result, leads to the formation of scrapes and ulcers.

Patients' legs may be exposedvarious damaging factors. Because of the increase in the sensitivity threshold, patients may not feel the effect of high temperature, for example, the burn of the rear surface of the foot when taking sun baths, or the plantar surface of the foot when walking barefoot on hot sand. Of the chemical factors, it should be noted the damaging effect of keratolytic ointments containing salicylic acid, which can lead to the formation of ulcers.

Ulcerative defect is often infectedstaphylococci, streptococci, colibacillus. Anaerobic microflora often takes place. Pathogenic microorganisms produce hyaluronidase, which leads to the spread of necrotic changes with the coverage of subcutaneous fat, muscle tissue, bone-ligament apparatus, in severe cases, there is a thrombosis of small vessels and, as a consequence, the involvement of new large areas of soft tissues. Infected lesion of the foot can be accompanied by the formation of gas in soft tissues, which is detected both palpation and x-ray. This condition is usually accompanied by hyperthermia, leukocytosis. In such cases, urgent surgical intervention is necessary with necrectomy, the appointment of adequate antibiotic therapy, careful monitoring of glycemia.

Principles of conservative therapy of a neuropathic infected form of the diabetic foot syndrome.

Timely and adequately conductedconservative therapy of non-ieropathic infected form of foot injury allows to avoid surgical intervention in 95% of cases. Treatment of the neuropathic infected foot includes the following main components:

1. Optimization of metabolic control

In most cases, patients withulcerative lesions of the feet, marked hyperglycemia. To ensure conditions favorable to healing, it is important to achieve a state of compensation for carbohydrate metabolism. With IDDM, intensification of insulin therapy is carried out. The body's need for insulin can increase significantly due to the presence of an infectious inflammatory process and high temperature, hence this requires an appropriate increase in the dose of insulin administered. Therefore, the benchmark for the optimal amount of the drug is not the ratio of the dose of insulin and the body weight of the patient, but the glycemic index.

Very often, the diabetic foot syndromedevelops in patients with NIDDM on the background of pronounced decompensation of the disease, which is not amenable to correction in spite of diet and treatment with oral hypoglycemic drugs. Such patients with NIDDM, in the presence of non-healing neuropathic ulcers or severe pain syndrome, it is recommended to translate into insulin therapy. In such cases, the appointment of insulin allows to normalize the glycemia and maintain good metabolic control.

2. Antibiotic therapy
Dry, thinned skin of the neuropathic foot withviolation of integrity has a reduced barrier properties against the penetration of microorganisms located on its surface. If there is an infection of the soft tissues of the foot, antibiotic therapy is necessary. The drugs of choice can be:

lincomycin, clindamycin
oxacillin, ampiox
The type, dose of the preparation and duration of treatment are determined on the basis of bacteriological data on the microflora of the wound detachable, the severity of the process and the rate of healing of the ulcer.

3. Unloading of the affected area
Full rest and unloading of the foot can lead tohealing for several weeks even for years of existing ulcers. This can be used as a wheelchair, crutches, and special unloading shoes.

4. Local wound treatment
Local wound treatment includes removal of necrotic tissues, treatment of the edges of the ulcer and ensuring aseptic wound surface and nearby foot areas.

5. Removal of hyperkeratosis sites
In the presence of sites of hyperkeratosis,timely removal of them with a scalpel with a shortened blade. This procedure is carried out by specially trained medical personnel. In some cases, after removal of the callus, a ulcerative defect is found.

6. Proper selection and wearing of special shoes

Treatment of patients with neuropathic ulcers
If there is a breach of the integrity of the skin withoutinvolving the soft tissues to be treated, it is sufficient for the patient to follow the recommended mode of unloading the limb or the affected area and perform local treatment of the ulcer with antiseptics (solution of furacillin, dioxidine). If there are signs of infection of ulcers, involvement in the pathological process of subcutaneous fat and muscle tissue, antibiotic therapy is necessary.

Diabetic osteoarthropathy (joint of Charcot)

Bony changes are manifested by osteoporosis,osteolysis, hyperostosis. Initial changes in the bones may not manifest themselves in a retgenological study. In this regard, for the early diagnosis of changes in the bone-ligament apparatus, the method of ultrasound scanning of the bone is used. Destructive changes can progress for several months and lead to severe deformation of the foot.

The development of these destructive changesis the cause of a high predisposition of this category of patients to fractures of the foot bones when compared with persons without neuropathy. The presence of a patient's neuropathy can mask spontaneous fractures of the foot bones; only a third of patients report pain. If after a fracture several days have passed, then the radiograph can have a normal picture, while the scanning shows significant changes. Palpation is marked hyperthermia of the foot area; when compared with the contralateral limb, the foot is edematous. Very often, this condition is mistakenly regarded as deep vein thrombosis or gout. Even a minor injury can serve as the cause of the fracture. Therefore, careful collection of anamnestic data is very important.

Patients with fractures or already formedSharco's joint recommend full discharge of the affected limb to the full consolidation of bones, and in the subsequent - wearing individual orthopedic shoes. In the presence of severe hyperostosis, the patient may have long-lasting, recurrent ulcers. In such cases, the removal of hyperostosis.

The accumulation of fluid in the tissues of the lower extremities,associated with neuropathy requires the exclusion of other causes of edema, namely: heart failure or nephropathy. The causes of the appearance of neuropathic edema have not been fully elucidated, but it can be assumed that they are a consequence of disorders in the autonomic nervous system, the formation of a variety of arteriovenous shunts and the violation of hydrodynamic pressure in the microcirculatory bed.

The most effective treatment isthe appointment of sympathomimetics, for example, ephedrine (30 mg every 8 hours). Ephedrine has a fairly rapid effect, consisting of a reduction in peripheral blood flow and an increase in sodium excretion. Along with the peripheral, ephedrine can also have a central regulating effect on water-salt metabolism.

Ischemic form of diabetic foot syndrome
Ischemic form is characterized by painfulsymptomatology, usually pain at rest. At the same time, some relief comes when the patient's position changes, for example, by giving an elevated position to the head end of the cot or hanging legs from the bed. To alleviate pain symptoms, lumbar sympathectomy is sometimes performed, but no improvement in hemodynamics of the lower limbs is observed.

Externally, the skin of the feet can be paleor cyanotic, or have a pinkish-red hue due to the expansion of the surface capillaries in response to ischemia. Unlike the neuropathic, in the ischemic form of lesion, the feet are cold. Ulcerous defects appear as acral necrosis (fingertips, marginal surface of heels). Provoking factors in terms of ulcerative defects are: wearing tight shoes, the presence of deformity, swelling of the foot. Often, a secondary infection is added, both aerobic and anaerobic. The cause of the violation of blood flow is the development of obliterating arteriosclerosis of the arteries of the lower extremities. In this case there is a clear tendency to generalized lesions of arteries of medium and small caliber. In patients with diabetes, atherosclerotic changes develop much more often than in the general population.

Treatment of ischemic form of diabetic foot syndrome

1. Use of conservative therapies (see above).

2. If the conservative therapy is ineffective, the question is raised about the possibility of a reconstructive surgery. The choice of the method of reconstruction depends on the level and type of damage:
a) percutaneous transluminal angioplasty;
b) thrombarterectomy;
c) distal vein shunting in situ.

3. The presence of other serious complications from the cardiovascular system, in particular, atherosclerotic lesion of the coronary vessels, limits the possibilities of a reconstructive surgical operation aimed at restoring the disturbed blood flow in the lower extremities. Therefore, in this category of patients in order to avoid the development of gangrene it is important to early detection of ulcerative lesions and control over the infection - the appointment of adequate antibiotic therapy, local treatment of the wound defect. In the presence of edema of the lower extremities due to heart failure, appropriate dehydration therapy is necessary.

With extensive purulent-necrotic lesionsamputation is performed, and amputations at the level of the lower third of the shin are the most favorable in terms of postmortem rehabilitation. The questions of post-mutilation rehabilitation are solved by orthopedic surgeons. Important in the future is prosthetics and the selection of orthopedic shoes.

Diagnosis of lesions of the lower extremities in diabetes mellitus

As it was said above, in the development of changes withthe lower extremities play a leading role such factors as neuropathy, ischemia, foot deformity and the presence of edema. When assessing the condition of the legs, it is important to determine in each specific case the place in the development of lesions is occupied by one or another factor and, in accordance with this, determine the tactics of further treatment.

Examination and palpation of feet and shins

It is the most simple and effective method of detecting lesions of the foot. It is important to pay attention to the following features:

color of extremities: red (with neuropathic edema or arthropathy of Charcot) pale, cyanotic (with ischemia), pink in combination with pain symptoms and absence of pulsations (severe ischemia)
deformations: hammer-shaped, hook-shaped toes, hallux valgus, hallux varus, protruding heads of metatarsal bones of the foot, arthropathy of Charcot
edema: bilateral - neuropathic, as a consequence of cardiac or renal insufficiency; one-sided - with an infected lesion or arthropathy Sharko
condition of the nails: atrophic with neuropathy and ischemia, change in color in the presence of fungal infection
hyperkeratosis: particularly pronounced in areas of the foot experiencing excessive pressure with neuropathy, for example, in the projection of the heads of metatarsal bones
ulcerative lesions: with neuropathic forms - on the sole, with ischemic forms - are formed in the form of an acral necrosis
pulsation: pulsation on the posterior and posterior tibial arteries of the foot is reduced or absent on both extremities with ischemic form and normal with neuropathic form
skin condition: dry thinned skin with neuropathy.
Neurological examination
1. Investigation of vibration sensitivity, which is carried out using a biotesiometer or graded tuning fork (Fig. 7).
Fig.7 Investigation of vibration sensitivity with a tuning fork in a patient with diabetes mellitus.

The threshold of vibration sensitivity is increased fromage, so the indicators should be compared with the nomogram curve, which reflects the change in the threshold of vibration sensitivity, depending on age.

2. Study of tactile and temperature sensitivity.

3. Definition of the Achilles tendon reflex.

Assessment of the state of the arterial blood flow
To assess the state of the arterial blood flowThe ankle-brachial index is measured using the Doppler apparatus. Systolic pressure is measured in the arteries of the legs and brachial artery. The ratio of the systolic pressure in the arteries of the lower limbs to the magnitude of systolic pressure in the brachial artery is the ankle-brachial index. Normally, it is 1.0 or higher. Critical in terms of the state of peripheral blood flow are indexes below 0.6, prognostically unfavorable - cases in which the ankle-brachial index is below 0.3.

If there is calcification of the tunica media of the arteries(sclerosis of Menkeberg), which is one of the manifestations of autonomic neuropathy, because of the change in the elasticity of the vascular wall for its compression, more pressure is needed in the cuff, so you can get a fake elevated ankle-brachial index. This phenomenon is observed in 10-15% of patients.

Angiography of the arteries of the lower extremities is the most informative research method, allowing to assess the level of stenosis or thrombosis, as well as its extent.

Prevention of lesions of the lower limbs in diabetes mellitus

1. Screening of patients with diabetes mellitus in terms of identifying the syndrome of diabetic foot consists in the timely identification of people who have an increased risk of ulcerative lesions of the lower extremities. Such risk factors include:

The presence of somatic and autonomic neuropathy
peripheral vascular injury
deformation of feet
leg injury in history
loss of vision
diabetic nephropathy, especially in the terminal stage of chronic renal failure
elderly age
absence of outside assistance (residence of the patient separately from relatives and friends)
excessive alcohol consumption
The defeat of the lower extremities often develops in men with excessive body weight.

2. Education of patients
Currently, the most effective formorganization of specialized medical care for patients with diabetes is the organization of training, which gives a real opportunity to achieve optimal control of the disease, as an important factor in preventing late complications. Structured training programs contain a section on the rules of proper foot care. Compliance with these rules can significantly reduce the risk of leg injury.

3. Proper selection of everyday shoes, making and wearing special, orthopedic shoes.

4. Regular medical supervision of the condition of the patient and his lower limbs. Examination of the legs should be performed each time during the visit of a diabetic patient to the doctor, but at least once every 6 months.