Diabetic Foot Ulcer: Causes and Treatments

Diabetics are prone to foot ulcers due to complications with their circulatory and neurologic systems. It is the nature of diabetes to run interference with both of these functions, which means there are several causes and potential risks of a diabetic foot ulcer:

Neurological System Effects: Peripheral neuropathy is similar in sensation to the ‘fat flip’ experienced after an anesthetic at the dentist’s office, and diabetics often suffer a similar loss of feeling in their feet and legs, meaning that they are not always aware of cuts or injuries that have occurred. A diabetic patient may believe that an ulcer “just appeared” when really it had been festering for several days.

Neurological and Circulatory System Effects: Diabetic patients also often fail to register when too much pressure is being applied to one area of the foot and may leave their limbs in a pressure-point situation that leads to ulceration. This failure of the body to shift positions, combined with a diminished circulatory system, means that ulcers are not only more likely to occur but will not heal as quickly due to a decrease in blood flow.

What is Diabetic Foot Ulcers?

When most people hear the word ‘ulcer’ they often think of the illness associated with the lining of the stomach, but in reality, this is just one type of ulcer found in or on the body. In simple terms, an ulcer involves layers of the skin breaking open and then not healing properly. Exterior skin ulcerations are usually accompanied by redness, swelling, and pain.

What Causes Diabetic Foot Ulcers?

There are several factors that contribute to the development of diabetic foot ulcers including, (but not limited to), impaired nervous system and circulatory system function:

  • Inability to feel pain in the foot and leg and thus unable to respond to the body’s distress signals.
  • Loss of protective reflexes: the sympathetic nervous system is often damaged and fails to communicate that pressure point friction or blood pooling has occurred.
  • Deformity of the foot structure: because diabetic patients don’t respond to pain stimuli deformities of the foot can occur from abnormal positioning and lead to decreased circulation and blood flow, both of which contribute to the development of ulcers.
  • Connective tissue changes: changes in glucose levels can change connective tissue structure which leads to a host of complications including a thickening of the sole pad, which may contribute to ulcer development.
    Poor foot care.
  • Improperly fitting shoes.

Complications Associated with Diabetic Foot Ulcers

Special care must always be taken with a diabetic patient to minimize the risk of ulcers forming, to begin with, as treating a patient with diabetes is much riskier than treating a patient without, for several reasons:

  • Once an initial ulcer develops the patient is at increased risk for the condition becoming chronic. This is an undesirable situation because a multitude of ulcers can continue to develop, which is not only frustrating but extremely dangerous to the health of a diabetic patient.
  • If the initial ulcer deepens or grows worse there is a serious increase in the risk of infection. When diabetics experience infection treating the affected area can be challenging, and if it cannot be brought under control it could lead to amputation.
  • The risk of amputation due to minor foot problems makes proper foot care just as critical to a diabetic’s health as correct and regular management of blood sugar and insulin levels

Venous Ulcer

Venous ulcers occur in the leg, frequently above the ankle, and are caused by problems with the veins in the leg. It is also one of the most common types of ulcers that diabetics suffer from; it accounts for about 70% of all cases of ulcerations in patients with diabetes.

Venous ulcers are caused by poor functioning of superficial and deep level veins, which compromises blood flow and triggers the onset of ulcer development. This is not a difficult ulcer to diagnose as the skin becomes quite swollen, dry, itchy, and occasionally discolored. The ulcer will suppurate and will likely show signs of eczema as well.

There are several things that can be done to prevent a diabetic ulcer of this type:

  • Walk regularly; take the stairs when you can
  • Consume plenty of fresh fruits and vegetables
  • Decrease saturated fat in your diet
  • Maintain a healthy weight; lose weight if necessary
  • Do not cross your legs when seated
  • Frequently move around and change the position of your feet and legs if you don’t ‘feel the need’ because you may never feel it; it still needs to be done
  • Wear support hose on a regular basis
  • When seated elevate your legs
  • Inspect your feet and legs regularly. Check for open sores, redness, swelling, or brownish-colored skin. You cannot rely on pain indicators so you must check manually for injuries and ulcers.

Arterial Ulcers

After Venous Ulcers, Arterial Ulcers are the second most common type of diabetic foot ulcer. While only 10% of ulcers are the Arterial kind they can be much more painful and more difficult to treat. While pain is not always a factor for diabetic patients this in no way diminishes the risks posed by this type of sore.

In fact, if left untreated arterial diabetic foot ulcers can pose exceedingly dangerous risks to the patient’s health, as the arteries are responsible for moving oxygenated and nutrient-rich blood from the heart to all other areas of the body. An arterial ulcer would interfere with this process, making quick identification and treatment of this particular ulcer absolutely crucial.

Arterial ulcers are most often found on the feet, particularly the heels, the ends of the toes, between the toes, and wherever the bones may protrude and create friction by rubbing against bed sheets, shoes, etc. These ulcers may also occur in the nail bed as a result of improper nail care.

Arterial diabetic foot ulcers are characterized by a ‘punched-out’ appearance and the skin may be cool to the touch. The surrounding skin may have a waxy, pale, taught appearance when the leg is elevated; when lowered the entire foot may turn red.

The following steps can help to reduce the risk of developing diabetic Arterial ulcers. They are the same suggestions for preventing venous ulcers and they are important and effective enough to bear repeating:

  • Increase movement even when indoors
  • Be selective on the kind of shoes you wear.
  • Dry your feet properly after a shower or a foot soak. This eliminates any moisture that could mature into something else.


Diabetes will eventually cause the small blood vessels to become permanently damaged, and atherosclerosis (narrowing of the arteries) is always a risk with this disease, and it has a devastating impact on the circulatory system. Combined with a deterioration of the nervous system atherosclerosis becomes one of the major causes and potential risks of a diabetic foot ulcer because it not only contributes to the problem but negatively interferes with the healing process as well.

Taking care of your general health, practicing good foot and nail maintenance, and regularly inspecting your legs and feet for signs of injury or damage are three crucial steps that must be regularly undertaken to reduce the risk of developing diabetic foot ulcers of any kind.

Scroll to Top