Claudication: symptoms, causes and treatment of leg pain on walking

Claudication is leg pain brought on by walking or exercise that settles with rest. The NHS says the medical term "intermittent claudication" is used for a painful ache in your legs when you walk that usually disappears after a few minutes of rest, and that the pain can affect 1 or both legs and range from mild to severe.

NICE Clinical Knowledge Summaries (CKS) describes intermittent claudication as the most common symptom of peripheral arterial disease: diminished circulation leads to pain in the lower limb on walking or exercise, relieved by rest. It also describes a progressive cramp-like pain in the calf, thigh or buttock on walking, relieved by resting.

Because leg muscles need more blood when they work, a narrowed artery that supplies enough blood at rest may not supply enough during exercise, so pain appears at a predictable distance and eases when you stop.

The NHS says many people with PAD have no symptoms. When symptoms appear, the main one is the painful ache on walking that settles with rest. Other symptoms of PAD that the NHS lists are listed below.

• Hair loss on the legs and feet.

• Numbness or weakness in the legs.

• Brittle, slow-growing toenails.

• Ulcers (open sores) on the feet and legs that do not heal.

• Changing skin colour on the legs, such as turning paler than usual or blue (this may be harder to see on brown and black skin).

• Shiny skin; in men, erectile dysfunction.

• Shrinking (wasting) of the leg muscles.

The NHS says PAD is a form of cardiovascular disease, usually caused by a build-up of fatty deposits (atheroma, made of cholesterol and other waste substances) in the walls of the leg arteries, which makes them narrower and restricts blood flow. This process is called atherosclerosis.

The NHS lists the things that increase the chance of developing PAD and other cardiovascular disease: smoking (the most significant risk factor), type 1 and type 2 diabetes, high blood pressure, high cholesterol, and growing older. NICE CKS names the same strong risk factors: smoking, diabetes, hypertension and hypercholesterolaemia.

The NHS says to see a GP if you experience recurring leg pain when exercising. Do not assume it is just age.

It also says that if PAD symptoms develop quickly or suddenly get worse, this could be a sign of a serious problem requiring immediate treatment. NICE CKS lists the features of acute limb ischaemia as pain, pallor, pulselessness, perishing cold, paraesthesia (pins and needles) and loss of power, and says emergency assessment by a vascular specialist should be arranged.

The NHS describes critical limb ischaemia (CLI) as an extremely serious complication in which blood flow to the legs becomes severely restricted. Symptoms include a severe burning pain in the legs and feet that continues at rest, skin turning pale, shiny, smooth and dry, wounds and ulcers that do not heal, loss of muscle mass, and skin on the toes or lower limbs that becomes cold and numb, then red and black, and may swell and produce smelly pus (gangrene). If you think you are developing symptoms of CLI, contact a GP immediately, or call 111 or use 111 online if you cannot reach one.

The NHS says PAD is usually diagnosed through a physical examination by a GP and by comparing the blood pressure in your arm and your ankle. A difference between the 2 may indicate PAD and is called the ankle brachial pressure index (ABPI).

NICE CKS says assessment of people with suspected PAD should involve a medical history, a physical examination and measuring the ABPI, and that an ABPI of 0.79 or lower suggests PAD.

NICE CKS includes differential diagnosis as part of the assessment, meaning other possible causes of leg pain are considered alongside PAD. Narrowing of the spinal canal (spinal stenosis) is one condition that can also cause leg symptoms on walking; see our spinal stenosis page.

The NHS says there is no cure for PAD, but lifestyle changes and medicines can help reduce symptoms and the risk of other cardiovascular disease such as coronary heart disease, stroke and heart attack. Treatment matters because having PAD is a sign that your blood vessels are unhealthy.

The two most important changes, according to the NHS, are exercising more regularly and stopping smoking. NICE recommends supervised exercise as one of the first steps; the NHS says this usually involves 2 hours of supervised exercise a week for 3 months, and that you should aim to exercise daily for the rest of your life because the benefits are quickly lost if exercise is not frequent and regular.

The NHS suggests walking as far and for as long as you can before the pain becomes intolerable, resting until it goes, then walking again until the pain returns, using this stop-start method for at least 30 minutes in total, several times a week. It acknowledges that the course is challenging because the frequent episodes of pain can be upsetting, but says it should improve symptoms.

The NHS says PAD is not immediately life-threatening, but the atherosclerosis behind it can lead to serious problems, because blockages in leg arteries can also affect the arteries supplying the heart and brain, making coronary heart disease, stroke, heart attack and angina more likely. With treatment, most people's symptoms remain stable and some experience an improvement in pain.

NICE CKS says all people with PAD should be offered information, advice, support and treatment for secondary prevention of cardiovascular disease, which is why medicines for cholesterol, blood pressure and clotting often form part of the plan even when leg pain is the main complaint.

On the NHS, claudication is usually assessed by a GP, with referral to a vascular service for supervised exercise, imaging or consideration of angioplasty or bypass. Access to supervised exercise programmes varies by area. Some people choose to see a vascular specialist privately, and the tests and treatments are broadly the same, with risk-factor management coordinated through your GP.