Diabetes is a chronic condition that is characterised by high blood glucose (sugar) levels. Diabetic patients are at a high risk for developing chronic wounds, especially in the feet. If left untreated, these wounds can cause serious problems that can lead to infections and eventually gangrene, which may require amputation.
In diabetic patients, foot ulcers or wounds that do not heal occur due to the two major complications of diabetes: nerve damage (neuropathy) and poor blood circulation.
- Neuropathy (nerve damage) causes numbness in your feet, reducing the ability to feel pain and discomfort. When you do not feel pain, even a small cut or a blister can form ulcers, sores and infections by going unnoticed.
- Good blood supply is very important for healing of tissues. Poor blood circulation, and thereby, insufficient oxygen supply in your feet is caused by diabetes-associated damage to the blood vessels. This makes healing difficult.
Other factors that can contribute to the risk of developing diabetic foot problems are: impairment of the immune system, fungal and bacterial infections, poorly fitting shoes and smoking.
Signs and symptoms of diabetic foot
If you are a diabetic, you should be aware of any problem that affects your feet. Early warning signs of foot problems that should be recognised include:
- Burning, tingling or acute pain in the feet
- Numbness of the feet or loss of sensation to heat, cold or touch
- Changes in the shape of the feet
- Loss of hair on the lower legs, feet and toes
- Changes in the colour of your foot and yellowing of toenails
- Appearance of blisters, ingrown toenails, sores or ulcers
- Infection of corns and calluses on the feet (thickened areas of skin that can become painful)
Complications of diabetic foot
Diabetic wounds are the most severe types of chronic (non-healing) wounds that can impair your quality of life. Complications can include:
- Wound infection: A small ulcer on the foot when left untreated can attract bacteria, resulting in skin and bone infections.
- Gangrene: Chronic wound infections may cause gangrene, a condition characterised by death of tissue
- Amputation: Chronic wounds may not respond to treatment and if serious enough, may require amputation
Your doctor will diagnose based on your medical history, symptoms, physical examination and the results of tests. The tests may include:
- Wound culture to detect an infection
- X-ray to detect bone infection
- CT scan and MRI to evaluate infection in case your doctor suspects the presence of pus
- Doppler or arteriographic studies to assess blood flow to the feet
- Blood glucose and glycohaemoglobin tests to assess the levels of glucose in the blood
- Complete blood count to determine white blood cell (WBC) count; high levels of which are indicative of infection
Mild foot infections generally heal with antibiotic or antifungal treatment. However, more serious problems may require corrective shoes, proper footwear, orthotic devices, splinting or bracing.
Corrective foot surgeries may sometimes be indicated for foot deformities that may progressively worsen. Surgical treatment is recommended for chronic wounds to control infection and create an environment that encourages healing and preserves the structural and physical integrity of the foot. Surgical treatment involves the following steps:
- Surgical debridement: This process involves the removal of dead and infected tissue, joints and bones, using a scalpel or special scissors. Your doctor may also place your affected foot in a whirlpool bath, apply wet to dry dressings or use a syringe and catheter (narrow tube) to pull away the dead skin, or dissolve it with the help of certain chemicals.
- Reconstruction: This process involves closing a large area of the operative wound.
- Antibiotic application: A catheter is used to apply antibiotics continuously to the wound.
- Skin defect covering: Once the infection has alleviated, surgical procedures to cover the skin defect may be performed.
Since chronic foot wounds are common in diabetics, taking a few preventive steps can keep your feet healthy.
- Avoid walking barefoot, especially on hot surfaces.
- Use a moisturiser for dry feet. Apply only to the heels and not between the toes.
- Don’t cut corns or calluses with scissors or razors.
- Trim your toenails straight across.
- Wash your feet regularly with warm water and dry them thoroughly especially between the toes.
- Wear comfortable and well-fitting shoes.
- Wear socks or stockings all the time.
- Check your feet regularly for cuts, sores, blisters or infections.
- Quit smoking.