Diabetic Foot

Diabetic foot problems are a serious complication that can develop when high blood sugar levels damage the nerves and blood vessels in your feet. While these complications can be severe, including the risk of amputation, most can be prevented through careful daily foot care and good diabetes management.

Table of contents

• What Is Diabetic Foot?
• How Diabetes Affects Your Feet
• Common Foot Conditions in People with Diabetes
• Serious Complications
• Risk Factors
• Daily Foot Care Tips
• When to See Your Healthcare Provider
• Prevention Through Diabetes Management

What Is Diabetic Foot?

Diabetic foot is a serious complication of diabetes that affects the feet of people with this condition. In Western countries, around 2% of people with diabetes develop foot ulcers each year^[1][3]. These problems are one of the most common reasons people with diabetes need to stay in the hospital^[3].

The condition includes a range of foot problems, from open sores and infections to tissue death, all of which develop because of nerve damage and poor blood flow caused by persistently high blood sugar levels^[1][2]. About 15% of people with diabetes will develop a foot or toe ulcer at some point in their lives^[2][3].

How Diabetes Affects Your Feet

Foot problems are common in people with diabetes and can develop over time when high blood sugar damages nerves and blood vessels in the feet^[1]. Two main problems cause diabetic foot complications: nerve damage and poor blood circulation.

Nerve damage, called diabetic neuropathy, can cause numbness, tingling, pain, or a complete loss of feeling in your feet^[1][4]. About half of all people with diabetes have some kind of nerve damage, and nerves in the feet and legs are most often affected^[4]. When you can’t feel pain, you may not know when you have a cut, blister, or open sore on your foot^[1][4]. Pain is your body’s way of telling you something is wrong so you can take care of yourself. About 50% of patients with neuropathy have no symptoms at all, making it difficult to recognize problems early^[7].

Poor blood circulation, also called peripheral arterial disease, happens when diabetes damages blood vessels and reduces blood flow to the feet^[1][2]. A wound may not heal well because the damaged blood vessels cannot supply enough blood to the injured area. Poor blood flow makes your foot less able to fight infection and heal properly^[5][9].

Common Foot Conditions in People with Diabetes

Any skin, nerve, or circulation problem with your foot has an increased risk of turning into an infection or another complication when you have diabetes^[2]. Common foot and toe conditions that could lead to complications include^[2]:

• Cuts, ulcers, burns, and blisters that don’t heal
• Dry, cracked skin
• Corns and calluses
• Fungal infections, like athlete’s foot and toenail fungus
• Ingrown toenails
• Hammertoes and bunions

Foot ulcers are open sores and are some of the most common types of foot problems for people with diabetes^[2]. These ulcers typically develop in areas where your foot repeatedly rubs or presses against shoes or other surfaces. Around 40% of diabetes-related foot ulcers become infected^[7]. Infections can develop rapidly because of poor circulation and a weakened immune system^[2][7].

Serious Complications

Having an infection and poor blood flow can lead to serious, life-threatening complications^[1][2].

Gangrene

Gangrene is a medical emergency in which blood stops flowing to a specific part of your body, and tissues in that area die^[2]. A foot infection that’s not treated in time can lead to gangrene. This means the muscle, skin, and other tissues start to die^[1]. Without prompt treatment, gangrene can be fatal^[2].

Symptoms of gangrene include changes in skin color (from red to brown, and ultimately to purple or greenish black), swollen skin, severe pain or a loss of feeling, skin that feels cool to the touch, a crackling sound when you press on your skin, sores and blisters that release blood or foul-smelling pus, chills, and fast breathing^[2].

Charcot Foot

Charcot neuroarthropathy, also called Charcot foot, is another serious complication. It should be easily preventable—most importantly, any person with neuropathy who has a warm, swollen foot should be treated as having Charcot foot until proven otherwise^[3]. This condition can lead to the collapse of the arch and create foot deformities^[7].

Amputation

If you have gangrene or a foot ulcer that does not get better with treatment, you may need an amputation—a surgery to cut off your damaged toe, foot, or part of your leg^[1]. It may prevent a bad infection from spreading and could save your life. In 2016, diabetes-related foot infections contributed to more than 130,000 lower-extremity amputations in the United States^[7]. About 85% of all amputations performed in diabetic patients are preceded by foot ulcers^[9].

The five-year mortality rate following amputation is approximately 50%, exceeding the mortality rate of many cancers^[7]. However, early treatment greatly reduces your risk of amputation^[2].

Risk Factors

Anyone with diabetes can develop nerve damage and foot problems, but certain factors increase your risk^[4]:

• Blood sugar levels that are hard to manage
• Having diabetes for a long time, especially if your blood sugar is often higher than your target levels
• Having overweight
• Being older than 40 years
• Having high blood pressure
• Having high cholesterol
• Smoking—it reduces blood flow to the feet
• Foot ulcers greater than 2 cm
• Foot deformities such as bunions, hammer toe, or Charcot foot
• A history of foot ulcers or past amputation
• Vision problems
• Kidney disease

The risk of foot ulceration and limb amputation increases with age and the duration of diabetes^[9]. Recent studies emphasize the very high prevalence of foot ulceration in people with diabetes on dialysis as a consequence of end-stage kidney disease. The mortality in this patient group is higher than for most forms of cancer^[3].

Daily Foot Care Tips

The best way to protect your feet is by controlling your blood sugar levels every day. This will help keep nerve and blood vessel damage from getting worse^[1]. Good foot care for people with diabetes includes the following steps^[1][4][16]:

Check Your Feet Every Day

Look for cuts, redness, swelling, sores, blisters, corns, calluses, or other changes in the skin and toenails, including warts or other spots that your shoes could rub^[1][4]. Make sure to check the bottoms of your feet too. Use a mirror if you can’t see the bottom of your feet, or ask a family member to help^[1][4].

Wash Your Feet Every Day

Use warm—not hot—water and soap^[1][4]. Don’t soak your feet because that can dry out your skin^[1][4]. After you dry your feet completely, you can use talcum powder or cornstarch between your toes. They soak up moisture that can cause infection^[1]. If you use lotion, don’t apply it between your toes^[1][4].

Care for Your Toenails

Trim your toenails straight across with a clipper^[1][16]. Don’t cut nails too short, as this could lead to ingrown toenails. If it’s hard for you to trim your own toenails, or if they’re thick or curve into the skin, have a podiatrist (foot doctor) do it for you^[1].

Handle Corns and Calluses Safely

Ask your doctor how to remove corns and calluses safely^[1]. Thick skin on your feet can rub and lead to sores. But removing it the wrong way could damage your skin. So you don’t want to cut the skin or use medicated pads or liquid removers^[1]. Never try to remove them yourself—visit your doctor for appropriate treatment^[19].

Wear Proper Footwear

Always wear well-fitting shoes and socks or slippers to protect your feet when walking^[1][16]. You don’t want to walk barefoot, even indoors^[1][4]. Be sure your shoes are smooth inside—a seam or pebble could rub your skin raw^[1]. Choose shoes with soft interiors and ample room for your toes^[16]. Consider specialized diabetic shoes that provide extra cushioning and support, especially if you have neuropathy or foot deformities. Always wear clean, dry socks and change them daily^[19].

Protect Your Feet from Temperature Extremes

Use sunscreen on exposed skin and don’t walk barefoot at the beach^[1]. In cold weather, wear warm socks instead of warming your feet near a heater or fireplace^[1]. If you have diabetic neuropathy, you may not be able to feel heat or cold properly, which can put you at risk for burns^[20].

Keep Blood Flowing to Your Feet

Put your feet up when you’re sitting^[1]. Wiggle your toes and circle your feet throughout the day. Don’t wear tight socks. Get plenty of activity that’s not too hard on the feet, such as walking^[1].

Get Regular Foot Exams

Get your feet checked at your healthcare visits^[1][4]. Even if you haven’t noticed a problem, it’s good to have your healthcare provider look at your feet. All patients with diabetes should have an annual screen to identify their foot ulcer risk status^[3]. Those with any risk factors require specific foot care education as well as regular contact with a healthcare professional, usually a podiatrist^[3].

When to See Your Healthcare Provider

Serious foot problems can develop quickly^[1]. See your healthcare provider right away if you notice^[1][2]:

• A cut, blister, or bruise on your feet that doesn’t start to heal in a few days
• Red, warm, or painful skin on your feet
• A callus with dried blood underneath
• Any changes to your skin or toenails, like cuts, blisters, calluses, or sores
• Frequent bleeding
• Discharge of fluid or pus
• Foul smell
• Skin discoloration
• Swelling

If you develop foot issues, see your healthcare provider as soon as possible. Early treatment is key to preventing serious complications^[2]. Small problems can become serious if they aren’t treated early^[4].

Prevention Through Diabetes Management

The most important thing you can do to prevent diabetic foot complications is to control your blood sugar levels^[1][4]. Keeping your blood sugar in your target range as much as possible is one of the most important things you can do to prevent nerve damage or stop it from getting worse^[4].

Other diabetes management habits that can help include^[4]:

• Don’t smoke—smoking reduces blood flow to the feet
• Follow a healthy eating plan
• Get physically active—10 to 20 minutes a day is better than an hour once a week
• Take medicines as prescribed by your doctor
• Keep your blood pressure under control
• Manage your cholesterol levels

Systematic assessment, counseling, and comorbidity management are hallmarks of effective secondary prevention for diabetes-related foot infections^[7]. Most diabetic foot ulcers should heal if there is adequate blood flow, infection is aggressively managed, and pressure is removed from the wound and its margins^[3].

Remember, there is a lot you can do to prevent a foot wound from becoming a major health problem^[1]. By taking care of your feet daily and managing your diabetes well, you can greatly reduce your risk of serious complications.