Leg ulcers: causes, treatment and how long they take to heal

The NHS says treatment of venous leg ulcers should always be carried out by a healthcare professional trained in compression therapy for leg ulcers, usually a practice or district nurse. The first step is to remove debris or dead tissue, wash and dry the ulcer and apply a dressing, which usually needs changing 1 to 3 times a week.

Compression is the main treatment. The NHS says a firm compression bandage is applied over the affected leg to improve vein circulation and treat swelling, and is usually changed with the dressing. Applying it is a skilled procedure. In some clinics specialist teams use alternatives such as special stockings or other compressive devices.

Before compression is used, a test called a Doppler measurement of the blood pressure in the arteries at your ankles is done to rule out peripheral arterial disease. The NHS says it is not safe to apply compression if ankle artery pressures are low.

The NHS says a venous leg ulcer can develop after a minor injury if there is a problem with circulation in the leg veins. Constant high pressure in the veins gradually damages the tiny blood vessels in the skin and makes it fragile, so it breaks easily after a knock or scratch. NICE CKS describes this as sustained venous hypertension, due to failed vein valves or a poor calf muscle pump.

The NHS lists factors that raise the risk: obesity, difficulty walking, previous deep vein thrombosis (DVT), varicose veins, previous leg injury or surgery such as a hip or knee replacement, and increasing age. NICE CKS adds immobility to the list.

Other types of leg ulcer have different causes, and the NHS notes that most ulcers caused by artery disease or diabetes occur on the foot rather than the leg.

The NHS describes venous leg ulcers as open, often painful sores in the skin that take more than 2 weeks to heal, usually on the inside of the leg between the knee and ankle. You may also have swollen ankles, darkened or discoloured skin around the ulcer, hardened skin that makes the leg feel hard, a heavy or aching feeling in the legs, flaky, scaly and itchy skin (varicose eczema) and visible varicose veins.

The sore may produce a foul-smelling discharge. The NHS says leg ulcers are unlikely to get better on their own because they usually need specialist medical treatment.

A venous leg ulcer can be susceptible to bacterial infection. The NHS lists worsening pain, a green or unpleasant discharge, redness and swelling of the skin around the ulcer (redness may be harder to see on black or brown skin), a high temperature and an unpleasant smell.

Contact your GP or leg ulcer specialist as soon as possible if you have signs of infection. The NHS says an infected ulcer is cleaned and dressed as usual with the leg elevated most of the time, and a 7-day course of antibiotics is prescribed to clear the infection.

The NHS says most venous leg ulcers heal within 6 months if they are treated by a healthcare professional trained in compression therapy. Some ulcers take longer, and a very small number never heal.

NICE CKS notes wide variation in published healing rates: six-month healing has been reported as 45% for people treated in the community and 70% for people treated in specialist clinics. It also says repeat cycles of ulceration, healing and recurrence are common.

The NHS says you will see your nurse at least once a week at the start of treatment, and less often once the ulcer is healing well.

The NHS lists several things that may help an ulcer heal more quickly. Keeping active by walking regularly helps, while sitting or standing still without elevating your legs can make ulcers and swelling worse. Keep the affected leg raised whenever sitting or lying down, and aim to elevate your feet for 30 minutes, 3 to 4 times a day.

• Wear the compression bandage exactly as instructed, and contact your nurse if there are problems rather than removing it yourself.

• Take it off and keep the leg elevated, then contact your doctor or nurse, if you get numbness or tingling in your feet or toes, unusual pain in the legs, feet or toes, or your toes become swollen or look pale or blue.

• Move your feet up and down and rotate your ankles regularly to encourage circulation.

• Lose weight if you are overweight, stop smoking and moderate alcohol, which the NHS says can help the ulcer heal faster.

• Avoid scratching itchy skin, which damages the skin and can lead to further ulcers; emollients help varicose eczema.

• Be careful not to injure the leg and wear comfortable, well-fitting footwear.

The NHS says diagnosis is largely based on your symptoms and an examination of the leg, standing and lying down, with a check of the pulses at the ankles. Your GP or nurse will ask about swelling, skin changes, diabetes, previous DVT, leg injury or surgery and any previous leg ulcer.

A Doppler test is done to rule out peripheral arterial disease, and you may be referred to a vascular specialist if the diagnosis is uncertain, or to a diabetic ulcer clinic or rheumatologist if diabetes or rheumatoid arthritis is the suspected cause. NICE CKS says assessment should also include examining the wound for signs of infection and looking for other causes of delayed healing.

The NHS says once you have had a venous leg ulcer, another could develop within months or years. The most effective way to prevent this is to wear compression stockings at all times when you are out of bed. NICE CKS recommends long-term use of below-knee graduated compression hosiery.

The NHS also lists losing weight, exercising regularly, elevating the leg when possible, stopping smoking, and treating severe varicose veins, which may involve sealing the veins with a catheter and radiofrequency or laser energy, or surgery.

On the NHS the first contact is usually your GP or practice nurse, with ongoing dressings and compression from a practice or district nurse, sometimes in a leg club or specialist leg ulcer clinic. Vascular and diabetes teams are involved if the cause is not venous.

Private wound care and vascular review are available, but the same principles apply: confirming the cause first, checking arterial blood supply before compression, and a long-term plan to prevent recurrence.