Venous leg ulcers are the most common type of skin ulcer. They mainly occur just above the ankle. They usually affect older people and are more common in women. About 1 in 50 people develop a venous leg ulcer at some stage. Venous leg ulcers can be painless but some are painful. Without treatment, an ulcer may become larger and cause problems in the leg. Skin inflammation (dermatitis) sometimes develops around a venous ulcer.

Non-venous skin ulcers are less common. For example, a skin ulcer may be caused by poor circulation due to narrowed arteries in the leg, problems with nerves that supply the skin, or other problems. The treatment for non-venous ulcers is different to that of venous ulcers.

What causes venous leg ulcers?

The root of the problem is increased pressure of blood in the veins of the lower leg. This causes fluid to ooze out of the veins beneath the skin. This causes swelling, thickening and damage to the skin. The damaged skin may eventually break down to form an ulcer.  The increased pressure of blood in the leg veins is due to blood collecting in the smaller veins next to the skin. The blood tends to collect and pool because the valves in the larger veins are damaged. The valves may be damaged by a previous thrombosis (blood clot) in the vein, or by varicose veins. Gravity causes blood to backflow through the damaged valves and pool in the lower veins.

How is a venous leg ulcer diagnosed?

The appearance of a venous leg ulcer is usually fairly typical. It often looks different to ulcers caused by other problems such as poor circulation or nerve problems. To rule out poor circulation as a cause, it is usual for a doctor or nurse to check the blood pressure in the ankle and in the arm. The ankle blood pressure reading is divided by the arm blood pressure reading to give a blood pressure ratio called the Ankle Brachial Pressure Index (ABPI). If the ratio is low (less than 0.8) it indicates that the cause of the ulcer is likely to be poor circulation (peripheral vascular disease) rather than venous problems. This is very important to know as the treatments are very different. An ABPI may be checked every six months or so to make sure the circulation to the legs remains good.

What is the treatment for venous leg ulcers?

The ulcer is dressed in a similar way to any other wound. Typically, a nurse will do this every week or so. The wound is cleaned when the dressing is changed - normally with ordinary tap water. However, an ulcer is unlikely to heal with just dressings. In addition to a dressing, the following treatments help the ulcer to heal.

Compression

Graduated compression is the recognised gold standard for the treatment of venous ulcers, usually in the form of four-layer bandaging. Unfortunately with some patients the bulkiness of the bandages leads to non-compliance. An alternative to bandaging could be the use of below-knee graduated compression hosiery.