Diabetic foot: symptoms, treatment and prevention
Diabetic foot is one of the major chronic complications of diabetes and the one that results in the most hospitalizations and the highest costs
According to the World Health Organization, about 15 percent of diabetics experience a foot ulcer that requires medical treatment
In most cases, the diabetic foot is related to a collection of other conditions, whether directly related to diabetes or not, which in turn require treatment at the same time as the foot.
We speak of diabetic foot when diabetic neuropathy and/or lower extremity arteriopathy compromise the structure of the foot and its function.
Diabetic neuropathy can alter skin sensitivity and thus the perception of pain and temperature, especially in the extremities; for this reason, the diabetic individual may more easily get foot lesions, which sometimes progress to form ulcers; these, in the case of vasculopathy, become particularly difficult to heal.
Ulcers are areas where, instead of skin, a sore forms surrounded by a red halo that tends to become infected.
The most significant problem related to foot ulcers in diabetics is the risk of a major amputation, i.e., performed above the ankle: although the diabetic population is 3 percent of the general population, more than 50 percent of all major amputations involve diabetics.
Types of diabetic foot
Diabetic foot comes in two main forms depending on the causes that cause it: neuropathic foot (caused by neuropathy) and ischemic foot (caused by arteriopathy).
The two pictures are profoundly different from each other, and in the diabetic population they occur in comparable percentages; however, in the vast majority of subjects especially of advanced age, the causes coexist and we therefore speak of neuroischemic foot.
A serious risk of complication for a diabetic foot, in the presence of an open ulcer, is the probable occurrence of an infection; in fact, this is often the real cause leading to amputation.
This is the most frequent and earliest picture.
It is a consequence of peripheral vasculopathy-typical in diabetes-due to the presence of atherosclerotic plaques that decrease (stenosis) or completely interrupt (occlusions) blood flow in one or more arteries of the lower limb.
When blood flow to the leg is reduced, the following signs and symptoms may appear:
- cramps in the calf or foot, which are accentuated by walking and reduce with rest (in the more severe forms, the pain is present even at rest, and becomes more intense at night);
- feeling of having a cold foot;
- pale, cold, shiny, thin skin on the foot (the pallor increases when lying down and when lifting the leg, which instead turns red or purplish when resting it on the ground);
- presence of ulcers on the big toe, fifth toe, heel, or between toes.
Together with vasculopathy, diabetic neuropathy is the typical cause of ulceration in the diabetic foot, being responsible for about half of all foot ulcers.
The most common diabetic neuropathy directly involved in the pathogenesis of the diabetic foot is diffuse symmetrical distal sensory-motor neuropathy with the typical “stocking” distribution (feet and calves).
Sensory-motor neuropathy is one of the most common complications of diabetes and affects at least one third of the diabetic population, but it is proportional to the duration of diabetes: after 25 years of diabetes, 50% of diabetics are affected.
When there is nerve damage, the patient may report the following symptoms:
- numbness, tingling, paresthesias, allodynia,
- changes in skin sensitivity,
- swelling of the feet and ankles.
Neuropathy, however, typically has an insidious onset, and some patients may evolve asymptomatically to the “numb foot” picture; these, unfortunately, are the cases most related to the onset of a foot ulcer.
Therefore, it becomes crucial to observe the signs as well.
The semeiology of neuropathic foot frequently involves:
- claw toes, hammer toes, overlapping toes,
- hallux valgus,
- accentuation of the plantar arch,
- prominent metatarsal heads,
- plantar hyperkeratosis and dryness of the skin,
- venous turgor,
- presence of circular ulcers on the soles of the feet, sometimes deep to the bones.
Many diabetic patients-especially in old age-present both vasculopathy and neuropathy, which contribute to the onset of diabetic foot with signs and symptomatology of both pictures described above.
Consequence of the previous pictures is often the formation of foot ulcers.
And a frequent and dangerous complication of an ulcer is infection.
Infection most often sets in on an ulcer that has been open for a long time and has not been properly treated.
An infected ulcer can cause systemic phenomena that can endanger not only the limb but the patient’s own life.
Signs and symptoms of diabetic foot
Depending on the type, the symptoms of diabetic foot can be summarized as:
- cramps in the calf or foot,
- feeling of cold foot,
- pale, cold, shiny, thin and dry skin of the foot,
- numbness, tingling, paresthesias, allodynia,
- changes in skin sensitivity,
- swelling of feet and ankles, venous turgor,
- deformation of the physiological structure of the foot,
- plantar hyperkeratosis,
- presence of ulcers.
Prevention of diabetic foot
The diabetic foot causes many discomforts in sufferers and is difficult to treat: preventing it is therefore of paramount importance.
The first form of prevention, of course, is to keep diabetes itself under control by strictly adhering to the diet and treatment that the doctor has prescribed.
Secondly, it is also necessary to take daily care of the extremities, to avoid the formation of ulcers, which would then be difficult to treat.
Below is a list of useful precautions to avoid the occurrence of foot injuries.
Take care of hygiene:
- Inspect the condition of the feet daily (possibly using a mirror);
- Wash the feet several times a day with warm water (not above 37°C) and soap, cleaning the nails with a soft brush;
- Dry the feet thoroughly but gently, paying special attention to the space between the toes (possibly using a hair dryer);
- Make sure feet are always clean and dry;
- Do not use calloused products;
- Moisturize the foot with specific creams (however, avoid the spaces between the toes);
- Avoid foot baths, disinfectants, iodine dye and alcohol, as they dehydrate tissues;
- Keep nails neither too long nor too short;
- Change socks daily;
- Change shoes often.
- Avoid using scissors and sharp objects to care for nails and calluses: better to use a file;
- Do not cut or puncture any boils or blisters;
- Do not walk barefoot;
- Avoid direct heat sources on the foot, such as hot water bags, space heaters, heaters, fireplaces, etc.
- Use comfortable shoes with a wide sole, round toe, heel no higher than 4 cm, closed and possibly leather;
- When wearing new shoes, check the foot after a few minutes of walking;
- If necessary, use soft insoles that redistribute weight on the feet as you walk;
- Avoid socks with thick seams or darns, and possibly wear socks inside out;
- Avoid socks that are too tight;
- Do not use synthetic fiber socks;
- Avoid the use of bulky dressings or patches that may be irritating to the skin.
- Show the doctor any foot or nail injury, even if insignificant;
- Tell the doctor if foot or calf pain, tingling sensation, or different sensitivity between feet appears;
- In case of a wound, wash it with a disinfectant soap, apply a little mercury-chrome to it, cover it with sterile gauze and a paper plaster, and show it to the doctor as soon as possible;
- Avoid smoking and alcohol;
- Engage in regular physical activity, both to help blood circulation and to keep blood sugar under control.
The choice of shoes, in particular, is extremely delicate and depends greatly on the state of the foot (foot still free of ulceration, foot already ulcerated, foot already operated on). Shoe and footbed evaluation should therefore be done in diabetology outpatient clinics, with periodic checkups, the frequency of which depends on the stage of the disease.
What to do in case of diabetic foot
In case of a diagnosis of diabetes and the presence of some of the signs and symptoms described above, it is necessary to contact your primary care physician or diabetes center of reference, for an accurate diagnosis and proper therapeutic approach.
In case of an infected ulcer, it is essential to be seen urgently.
Diabetic foot therapies
The therapy of diabetic foot depends on the causes causing it (neuropathy or arteriopathy) and especially on the severity of the condition (with or without ulcer, with or without infection, etc.).