Diabetic Foot Ulcer

Causes

Diabetes can cause problems with blood flow in feet and nerve damage. Poor blood flow will make it harder for damaged skin to heal. Damage to the nerves can make it hard to feel pressure, blisters, or other injury to the feet. This makes it hard to prevent sores and can lead to larger sores.

The ulcer itself is usually caused by:

• Repetitive trauma or pressure on the foot
• A puncture wound on the foot
• Objects in the shoe that can damage the skin, such as a small rock

Risk Factors

The risk of diabetic foot ulcers is higher in those with:

• Neuropathy—numbness, tingling, or burning sensation in the feet
• Peripheral artery disease (PAD)—poor blood flow in the legs
• Improperly fitted shoes
• A foot deformity, such a bunion
• Diabetes for more than 10 years
• Poor diabetes control (HbA1c > 9% )
• Not wearing shoes
• A history of smoking

Symptoms

Symptoms of a diabetic foot ulcer may include:

• Sores, ulcers, or blisters on the foot or lower leg
• Pain
• Problems walking
• Discoloration in feet: black, blue, or red
• Fever, skin redness, swelling, or other signs of infection

Diagnosis

The doctor will ask about symptoms and past health. A physical exam will be done. A foot specialist may be needed. Fluid from the wound and blood tests may be done to look for signs of infection. Other tests may include:

• Doppler or arteriographic ultrasound to assess blood flow
• X-ray to look for infection
• MRI scan or CT scan to look for bone infection

Treatment

Early treatment can prevent more problems. The goals are to:

• Heal the ulcer
• Prevent infection
• Prevent future foot ulcers
• Avoid having to surgically remove all or part of the foot

Treatment options include the following:

Wound Care

Good wound care is important to help the ulcer heal and prevent infection. It will include keeping area clean and bandaged. Special bandages can help the wound heal faster. Other steps that can help during recovery include:

• A special cast or boot may be needed to ease pressure on the ulcer.
• Good blood glucose control can help the area heal. High blood glucose can slow healing and increase the risk of infections. Infected ulcers can also raise blood glucose levels. Changes to blood glucose care plan may be needed.
• Quit smoking. Smoking can slow healing.
• Proper footwear can decrease further injury.
• Antibiotics may be needed if there is an infection.

Skin Graft

Some large skin ulcers may have a hard time fully healing with basic care. A skin graft can use a section of skin from somewhere else to help the wound heal. The patch of skin may be taken from other area of the body, from donors, or be manmade skin.

Surgery

Dead tissue can build up inside and around the wound. This tissue will slow or prevent healing and raise the risk of infection. Surgery may be needed to remove the dead tissue and clean the wound. This surgery is called debridement. Surgery may also be needed to improve blood flow to the legs.

Sometimes an infection is too severe or does not respond to treatment. Amputation may be needed if the area cannot heal and tissue continues to die. Part of the foot is removed to stop infections from spreading to the rest of the body.

Other Treatments

Hyperbaric oxygen therapy may help with healing. Pure oxygen is pumped into a chamber to increase the amount of oxygen in the blood. The extra oxygen can improve the ability to heal.

Negative pressure wound therapy may also be used. A vacuum device and dressing help to draw fluid and infected tissue away from the wound. This can help the wound heal faster for some.

Prevention

Steps that can help keep feet healthy:

• Daily care including washing, drying well, and using socks
• Daily inspection of feet to look for injuries or sores
• Regular medical care for diabetes
• Use properly fitting shoes and socks
• Stop or avoid smoking
• Physical activity on most days of the week
• Proper care for calluses or toenails that are hard to trim