A diabetic foot ulcer is where an area of skin has broken down and you can see the underlying tissue. Most skin ulcers occur on the lower legs or feet. The skin normally heals quickly if it is cut. However, in some people with diabetes the skin on the feet does not heal so well and is prone to developing an ulcer. Foot ulcers are more common if you have diabetes because of neuropathy and/or the narrowing of blood vessels to the feet.
Neuropathy is a complication of diabetes called peripheral neuropathy of diabetes. Elevated blood sugar levels can damage the nerves that take messages of sensation and pain from the feet. Neuropathy can feel like pins and needles or cause loss of feeling in the feet.
Peripheal Vascular Disease is a complocation of diabetes you have an increased risk of developing narrowing of the arteries (peripheral vascular disease). This is caused by fatty deposits called atheroma that build up on the inside lining of arteries (sometimes called furring of the arteries). This can reduce the blood flow to various parts of the body.
The arteries in the legs are quite commonly affected. This can cause a reduced blood supply (poor circulation) to the feet. Skin with a poor blood supply does not heal as well as normal and is more likely to be damaged. Therefore, if you get a minor cut or injury, it may take longer to heal and be prone to becoming worse and developing into an ulcer. In particular, if you also have reduced sensation and cannot feel the wound.
The nerves that take messages of sensation and pain from the feet are commonly affected. If you lose sensation in parts of your feet, you may not know if you damage your feet. For example, if you tread on something sharp or develop a blister due to a tight shoe. This means that you are also more prone to problems such as minor cuts, bruises or blisters. Also, if you cannot feel pain so well from the foot, you do not protect these small wounds by not walking on them. Therefore, they can quickly become worse and develop into ulcers.
What increases the risk of developing foot ulcers?
- If you have reduced sensation to your feet (see above). The risk of this occurring increases the longer you have diabetes and the older you are. Also, if your diabetes is poorly controlled. This is one of the reasons why it is very important to keep your blood sugar level as near normal as possible.
- If you have narrowed arteries (see above). The risk of this occurring increases the longer you have diabetes, the older you become and also if you are male. Also, if you have any other risk factors for developing furring of the arteries. For example, if you smoke, do little physical activity, have a high cholesterol level, high blood pressure or are overweight.
- If you have had a foot ulcer in the past.
- If you have other complications of diabetes, such as kidney or eye problems.
- If your feet are more prone to minor cuts, grazes, corns or calluses which can occur:
- If you have foot problems such as bunions which put pressure on points on the feet.
- If your shoes do not fit properly, which can put pressure on your feet.
- If you have leg problems which affect the way that you walk, or prevent you from bending to care for your feet.
Are foot ulcers serious?
Although foot ulcers can be serious, they usually respond well to treatment. However, foot ulcers can get worse and can take a long time to heal if you have diabetes, particularly if your circulation is not so good. In addition, having diabetes means you are more likely to have infections and an infection in the ulcer can occur. Occasionally, more serious problems can develop, such as gangrene.
What can I do to help prevent foot ulcers?
Have your feet regularly examined
Most people with diabetes are reviewed at least once a year by a doctor and other health professionals. Part of this review is to examine your feet to look for problems such as reduced sensation or poor circulation. If any problems are detected then more frequent feet examinations will usually be recommended.
Treatment of diabetes and other health risk factors
As a rule, the better the control of your diabetes, the less likely you are to develop complications such as foot ulcers. Also, where appropriate, treatment of high blood pressure, high cholesterol level and reducing any other risk factors will reduce your risk of diabetic complications. In particular, if you smoke, you are strongly advised to stop smoking.