Things to know about diabetes foot problems
Diabetes can cause a variety of foot problems.
- A number of different kinds of foot problems can occur in people with diabetes.
- Two main conditions, peripheral artery disease (PAD) and peripheral neuropathy, are responsible for the increased risk of foot problems in people with diabetes.
- Symptoms and signs of diabetic foot problems arise due to the decreased sensation from nerve damage as well as the lack of oxygen delivery to the feet caused by vascular disease.
- People with diabetes have an increased risk of ulcers and damage to their feet.
- Diabetic foot problems also include bunions, corns, calluses, hammertoes, fungal infections, dryness of the skin, and ingrown toenails. These problems are not specific to diabetes but may occur more commonly due to the nerve and vascular damage caused by diabetes.
- Treatment depends on the exact type of foot problem. Surgery or even amputation may be required in some cases.
- Gangrene (dry gangrene) is tissue death due to the absence of blood circulation. It can be life-threatening if a bacterial infection develops (wet gangrene).
- Many diabetes-related foot problems can be prevented by good control of blood sugar levels combined with appropriate care of the feet.
How can diabetes cause foot problems?
Both type 1 and type 2 diabetes cause damage to blood vessels and peripheral nerves that can result in problems in the legs and feet. Two main conditions, 1) peripheral artery disease (PAD), and 2) peripheral neuropathy are responsible for the increased risk of foot problems in people with diabetes.
- Peripheral artery disease (PAD), sometimes referred to as peripheral vascular disease (PVD), means that there is narrowing or occlusion by atherosclerotic plaques of arteries outside of the heart and brain. This is sometimes referred to as "hardening" of the arteries. Diabetes is a known risk factor for developing peripheral artery disease. In addition to pain in the calves during exercise (medically known as intermittent claudication), the signs and symptoms of peripheral artery disease relate to a decreased delivery of oxygen to the lower legs and feet. In severe cases, the lack of oxygen delivery to tissues can result in ulcers and even gangrene (tissue death).
- Peripheral neuropathy refers to damage to the peripheral nerves directly as a result of diabetes. Symptoms of peripheral neuropathy include decreased sensation in the nerves of the legs and feet, making it difficult to perceive injuries due to lack of feeling. Peripheral neuropathy also causes tingling, pain, or burning in the involved areas. It can also cause the muscles of the feet to work improperly, leading to misalignment of the foot that can put pressure on certain areas of the foot.
Peripheral Artery Disease (PAD or PVD) Symptoms
Peripheral artery disease (or peripheral vascular disease) symptoms include:
- Intermittent claudication
- Pain at rest
- Numbness in the extremities
- Weakness of the calf muscle
- Hair loss
- Coldness in the legs or feet
What are the symptoms and signs of foot problems caused by diabetes?
In the most severe case, as mentioned above, due to a combination of decreased sensation and reduced blood flow to the feet, ulcers may develop. If the tissues continue to receive insufficient oxygen, tissue death (gangrene) occurs. Gangrene is a serious and potentially life-threatening condition. Other potentially serious problems that may develop include cellulitis (infection of the tissues beneath the skin) and osteomyelitis (infection of the bone); sepsis (the infection spreads to the bloodstream) also is possible.
People with diabetes are at increased risk for milder problems with the feet that are not specific to diabetes but may occur more frequently due to problems with the nerves and circulation to the feet.
Some of these conditions are: (This list is not exhaustive.)
- Calluses and corns, that may develop due to abnormal alignment of the feet or abnormal gait
- Fungal infections of the nails, which can appear as thickened, discolored, and at times brittle nails
- Tinea pedis, or athlete's foot, a fungal infection of the skin of the feet
- Hammertoes, or bent toes due to muscle weakness.
- Bunions, or the angling of the big toe toward the second toe. The area of the bunion may become reddened and irritated, leading to callus formation.
- Ingrown toenails
- Cracking of the skin of the feet, especially the heels, due to dry skin
Diabetes Nerve Pain: Improving Diabetic Peripheral Neuropathy
What are treatment options for diabetes foot problems?
Treatment depends upon the type of foot problem. For example, some problems such as corns may require wearing corrective shoes, while others such as mild infections may be treated with antibiotics or antifungals. Other problems may need surgical debridement and antibiotics. Gangrene, or tissue death, cannot be reversed, but treatments are available to prevent gangrene (often termed dry gangrene) from spreading or becoming infected (dry gangrene becomes infected and develops into wet gangrene). Surgical removal of the dead tissue is typically required, and antibiotics are given to prevent the development of life-threatening infections in the dead tissue. In severe cases of gangrene, amputation of the affected part may be necessary.
Other types of foot problems can be relieved by proper footwear, sometimes with orthotic devices, and splinting or bracing. For some conditions like hammertoes, bunions, and ingrown toenails; surgery may be necessary to correct severe cases.
Taking proper care of your feet (see Prevention section) can help prevent or relieve many common foot problems in people with diabetes.
Is it possible to prevent diabetes-related foot problems?
Some diabetes foot-related problems can be prevented by taking careful steps to observe and care for your feet. Keeping blood sugar levels under control (in the ranges advised by your doctor), and following your recommended diet and exercise program are the best ways to prevent all complications of diabetes, including foot problems. In addition to keeping your diabetes under control, you can take steps to care for your feet, including the following:
- Wear comfortable, closed-toe footwear at all times. Special shoes are available for people with bunions or foot deformities if these are necessary. Be sure no objects are trapped inside the shoes that could cut or injure your feet.
- Don't walk barefoot, even at home. Be sure your feet do not get burned by walking on very hot pavement in summer
- Always wash your feet with warm water and dry them well after washing.
- Check your feet daily for any sores or problems.
- Apply lotion to dry areas, especially heels, but don't use lotion between the toes. Corns and calluses can be lightly smoothed with a pumice stone. Never use scissors or razors to cut away corns or calluses.
- Trim toenails straight across, and do not cut the corners shorter than the rest of the nail.
- Be sure that your doctor checks your feet at every checkup.
- Stop smoking if you are a smoker. Smoking further increases the risk of arteriosclerosis and poor circulation to the feet.
What is the prognosis for diabetes-related foot problems?
The outlook depends upon the severity of the foot problem. As mentioned before, gangrene can be life-threatening if a bacterial infection develops in the dead tissue area. Severe gangrene may result in the necessity for amputation of the affected area. Other foot problems are less severe but may nevertheless lead to reduced function or discomfort. Patients need to understand that the best outcome of foot problems caused by diabetes is life-long monitoring of their feet for problems and consulting their doctor immediately if a problem begins to develop.
Diabetes is defined best as...
Medically Reviewed on 11/17/2022
Bronze, M.S. "Diabetic Foot Infections." Medscape. Jan. 16, 2020. <https://emedicine.medscape.com/article/237378-overview>.
Khardori, R.K. "Type 2 Diabetes." Medscape. May 31, 2022. <https://emedicine.medscape.com/article/117853-overview>.
National Diabetes Information Clearinghouse.