Foot care is an important part of treating your diabetes. In fact, keeping an eye on your feet can help prevent major problems, including amputation. “In the diabetic patient, there are many complications involving the lower limbs,” says Diane Koshimune, DPM, a podiatrist at Kaiser Permanente in California. “The feet are important in our day-to-day lives. If something happens to them, it can impact your ability to walk, to get around, to work.”
Nerve damage causes complications
Poorly controlled diabetes can cause a number of complications. One of the main concerns is nerve damage to the feet, a condition called diabetic peripheral neuropathy (DPN). It is estimated that around 50% of people with type 2 diabetes and 20% of those with type 1 diabetes will develop DPN.
Depending on which nerves are affected, this can be either very painful or rob you of sensation in your feet. If it impacts the small nerves, then signals to your brain about pain and temperature can be disrupted. Attacking the larger nerves can result in not being able to detect pressure and touch or maintain balance. If you have DPN, you are most likely to have a mixture of both issues.
“Because of nerve damage, people can’t feel their feet,” says Robert Gabbay, MD, PhD, Chief Scientific and Medical Officer for the American Diabetes Association (ADA). “The result is that minor problems that occur from too much pressure or ill-fitting shoes don’t result in a signal that something is wrong. So, instead of [the person] readjusting [their] shoes or getting out a pebble, the injury continues, leading to calluses and ultimately an ulcer.”
The most commonly described symptoms of DPN are a sensation of numbness, a “pins and needles” tingling, and weakness in the affected area of the body. Some may experience a sharp, what is called “lightening-like,” pain. Others may have a more burning, throbbing, or stabbing pain.
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Causes not well understood
How diabetes harms these nerve cells is still not well understood. Poor control of blood sugar levels is almost certainly one of the causes. Emerging research suggests that there are other contributors as well:
- Obesity and high triglycerides (a type of blood fat) may double the risk.
- Smoking may increase the risk of DPN by 42%.
- High blood pressure has been found to up the likelihood of nerve damage from 11% to 65%.
- Low levels of “good cholesterol,” high-density lipoprotein (HDL), and high readings of “bad cholesterol,” low-density lipoprotein (LDL), boost risk by up to 67%.
“While cuts and infections are important, you can also have poor outcomes from broken bones that you do not feel,” notes Dr. Koshimune. “Your leg or foot may be a little swollen, but since you feel no pain, you go about your normal day. You finally realize that something is wrong when your foot begins to change shape.”
Peripheral vascular disease
Another common foot complication in diabetes is peripheral vascular disease (PVD). In this case, the flow of blood through your feet and legs is lessened because of fat deposits that narrow or block the arteries.
“Blood flow issues from damage to the cardiovascular system can also have devastating results,” says Dr. Gabbay. “This makes you more prone to infection and also can impede healing.”
Signs and symptoms
Many people, especially in the earlier stages of PVD, may have no symptoms, or they may have severe muscle pain that goes away with rest. Called “claudication,” this pain is usually triggered by very moderate exercise, such as walking or going up stairs. As it worsens, they may get severe pains even when sitting or lying down.
Some of the other signs and symptoms can mimic DPN, such as leg numbness or weakness. PVD may also be seen as coldness in your lower leg or foot, especially when compared with the other leg or foot; sores on your toes, feet, or legs that won’t heal; color changes in the legs; hair loss or slowed hair growth; shiny skin; slowed growth of your toenails; and no or weak pulses in your legs and feet. Men may also have problems with erectile dysfunction.
DPN and PVD are often found together, compounding the risk for serious outcomes such as an infection that spreads to the bloodstream (called sepsis) or into the bones, leading to amputation. Lack of sensation in your lower extremities can be very dangerous, resulting in not finding injuries such as blisters from your shoes or cuts from walking barefoot.
In addition, when the blood supply is compromised by PVD, nutrients may not get to where they are needed. White blood cells and other components that fight infection and help promote healing are not able to reach the infection, resulting in it worsening.
Daily actions to improve foot health
Foot care is an important part of keeping your lower limbs in good health. Here are some steps you can take each day to help avoid serious complications.
- Inspect your feet carefully, looking for signs of damage such as small cuts, scrapes, infected toenails, blisters, or calluses.
- Wash your feet with warm, but not hot, water, and make sure you dry them off completely to avoid having warm and wet spots for fungus to grow. Use your elbow to test the water temperature before washing your feet.
- Keep the tops and bottoms of your feet moisturized (but not between the toes, as this may increase the chances of a fungal infection).
- Don’t go barefoot, as this increases the possibility of injury and infection.
- Quit smoking, as this habit decreases blood flow to the feet.
- Take daily walks, which can help increase blood flow.
- If you are trimming your toenails, trim straight across and don’t round off the corners or cut down the sides of the nail. Smooth them with a nail file.
- Wear appropriate, well-fitting shoes to avoid blistering. (A professional measurement can help you find the best fit.) Keep an eye on your feet to check for areas where your shoes may be consistently rubbing and breaking down the skin.
- If your diabetes or age have impacted your vision, ask a family member to examine the bottoms of your feet and between your toes thoroughly. You also may want to use a mirror to look at the undersides of your feet. (Some mirrors specially designed for foot inspection have telescoping handles, magnifying surfaces and lights.)
Glucose control also important
“The best way to prevent problems with your feet is to work closely with your primary care physician or diabetes specialist in managing blood sugar control,” says Dr. Koshimune. “The better the control, the better your chances of proper healing or at least limited damage. With poor control, the lack of healing can lead to multiple surgeries needed to close up the skin or remove the infection.”
Many people are able to manage their foot care by themselves. However, if you are losing feeling, you will need to stay in closer contact with your personal physicians and/or a podiatrist.
People with diabetes can be divided into two groups based on their risk of foot complications. A simple test helps differentiate between the two groups: The monofilament test uses a small, thin wire to apply pressure to various places along your legs and feet. If you don’t feel it, your risk is increased. If you also have reduced blood flow or a foot deformity, you are in an even higher-risk group. Those at greatest risk may be advised not to trim their own toenails and to see a podiatrist more often.
“Once upon a time, we used to say that everyone should absolutely see a podiatrist, but now we work in a team environment,” said Dr. Koshimune. “If you have neuropathy, you should be seen every year or so, but foot evaluations are typically managed by your primary care provider. [For] those who have other concerns, such as vascular disease or bone malformations, you should have an appointment every 90 days. Those with a previous ulcer or surgery may be seen more frequently. Calluses or blisters should be seen right away.”
Work with your health care team on self-care
Follow your health care team’s lead on what foot care you can or cannot do yourself. Depending on your situation, certain measures, such as trimming your toenails, may be best taken care of by your podiatrist. “I want you to take charge of your own health care, advocate for yourself and ask to see specialists if you think they are needed and available in your area,” says Dr. Koshimune. “Unfortunately, there isn’t a pill for everything. But there are things you can do to lead a normal life.”
Want to learn more about keeping your feet healthy with diabetes? Read “Caring for Your Feet When You Have Diabetes,” “How to Choose Footwear” and “Diabetic Foot Ulcers: What Are They and How You Can Avoid Them.”