Diabetes, when uncontrolled, can have a profound effect on many systems: eyes, heart, kidney, nerves, and feet. When sugar becomes elevated, it forms alcohol that can damage the insulation of the nerves that supply the feet. This may result in abnormal sensations to the feet such as sharp, shooting, tingling, burning pains, and may lead to complete numbness. This is known as neuropathy and can be dangerous when the foot does not feel injury from pressure, sharp objects, hot and cold temperatures.
At times, neuropathy can lead to the formation of limb-threatening holes in the feet (or ulcerations). This is important as more than 80% of amputations begin with foot ulcerations. Approximately 15-25 % of diabetics will develop foot ulceration in their lifetime. Up to 85% of lower limb amputations are the result of foot ulceration. To prevent this serious complication and bring about early detection of neuropathy, every diabetic should visit a podiatrist at least once a year. During this exam, the doctor will test for neuropathy using a small filament and a tuning fork to see if the feet are still feeling properly. In addition, other non-invasive tests such as the knee-jerk reflex test with a patellar hammer and joint position tests may be performed to evaluate for neuropathy. These tests are simple to perform and are non-painful.
As part of a regular foot exam, the podiatrist will examine both feet for circulation status by checking for a pulse in each foot to ensure there is adequate blood flow to the toes. This is important as diabetes can result in a decreased blood flow to the legs and feet that also can lead to amputation if undetected. In select cases, your podiatrist may want to order a special ultrasound or arterial doppler of the feet and legs to further evaluate the blood flow. Should the blood flow be reduced or absent, the podiatrist will often refer the patient to a vascular surgeon for further evaluation and possible revascularization to restore blood flow to the legs.
WHY SHOULD I BE CONCERNED ABOUT MY FEET?
Diabetics can easily have problems with their feet and especially when they have poor blood flow or neuropathy. These may both lead to poor healing and result in amputation. Neuropathy is particularly dangerous as the foot may act as if it is completely oblivious to simple basic injuries to temperature and pressure. This often delays prompt medical care and makes matters worse.
HOW CAN I PROTECT MY FEET?
- Check your feet daily between your toes and on the bottoms for redness, cracks, breaks in the skin, and blisters
- Check the soles of your shoes for penetrating objects before you put them on
- Check inside your shoes for anything that may have fallen into them
- Seek help immediately from your podiatrist if you notice redness, cracks, breaks in the skin
- Avoid self-treating your feet which may make problems worse
- Avoid the use of over-the-counter corn and callus removers that contain harmful acids and may produce ulceration.
- Avoid narrow shoes
- Break-in new shoes slowly and inspect your feet regularly during this time
- Schedule an appointment with your doctor if you notice non-healing sores or wounds
- Avoid walking barefoot
- Avoid tobacco
- Let your doctor know if you are unable to walk 1-2 blocks without calf, leg, or buttock pain. This may indicate more serious problems with blood flow
WHAT ELSE SHOULD I CONSIDER ABOUT SHOES AND SOCKS?
- When buying new shoes, get measured
- Buy your shoes late in the day when your feet are more swollen
- Look for diabetic socks or socks with bamboo that wicks away moisture
- A correctly fitted sock should never indent your skin
- Ask your podiatrist about extra-depth or double-depth shoes made for diabetics that reduce injury over bone prominences such as bunions and hammertoes
- Break-in new shoes slowly starting with one hour the first day and gradually increasing by an hour each day and performing regular skin exams
HOW OFTEN WILL MY DOCTOR CHECK MY FEET?
Your podiatrist will want to see you every year at a minimum unless it is identified that you have risk factors such as neuropathy or vascular disease. If this is the case your podiatrist will likely have you return at 9-12 week intervals for regular nail and callus care and sooner if other problems arise. Should anything new develop during those visits you will want to contact your podiatrist immediately for an appointment to seek proper medical attention.