Restless Legs Syndrome (RLS) - Exams and Tests

Exams and Tests

A doctor diagnoses restless legs syndrome by asking questions about your symptoms. A physical exam may be done to look for other possible problems that could be causing your symptoms.

Restless legs syndrome is diagnosed by your doctor based on the following four criteria:

• You have an urge to move your legs, usually because of uncomfortable sensations such as tingling, "pins and needles," prickling, crawling, or pain. In some cases, you may not feel any unpleasant sensations but still feel the urge to move your legs or your arms.
• The sensations and the urge to move your legs begin or get worse during periods of rest or inactivity, such as when you are sitting or lying down.
• The sensations and the urge to move your legs are partially or totally relieved by movement. But relief may be temporary and only last while you are walking, stretching, or moving your legs.
• The urge to move your legs and the sensations are worse in the evening or at night. But some people may have severe sensations and urges to move their legs throughout the day and night.

Other factors that may support a diagnosis include:

• Having a family history (in a parent or sibling) of restless legs syndrome.
• Having periodic limb movements—involuntary jerking or movement of your legs—while you are awake or asleep.
• Showing improvement when the medicine dopamine is used.

A sleep study called a polysomnography may be done to help your doctor diagnose restless legs syndrome or rule out other sleep disorders. This test records the electrical activity of your brain, eye movements, muscle activity, heart rate, breathing, air flow through your nose and mouth, and blood oxygen levels.

Although this test is not essential, it provides details of limb movement symptoms. These details may help evaluate the severity of your symptoms. The severity ranges from people who have restless legs syndrome occasionally, with only mild difficulty falling asleep, to those who have it frequently, with repeated interruptions of sleep. Serious sleep problems can greatly affect your ability to function during the day.

Common problems with diagnosing restless legs syndrome

Many cases go undiagnosed because:

• Many people do not seek a doctor's help when they have symptoms.
• Most people visit a doctor during the day, when symptoms are not present or are only mild.
• Some doctors do not recognize the condition and may believe that the symptoms are caused by other conditions, such as insomnia, stress, muscle cramps, or arthritis.

Restless legs syndrome does occur in children but it is difficult to diagnose for the same reasons. Children often are not able to describe their symptoms. A parent's observations of the child's behavior and sleep may be helpful. Knowing that a parent or other close relative has restless legs syndrome can also help the doctor make a diagnosis of restless legs syndrome in the child.

Other conditions to consider

Polysomnography and related sleep study tests may also be done to help identify problems that can interfere with sleep. You may be evaluated for other conditions with symptoms similar to restless legs syndrome. These conditions include varicose veins, arthritis, or intermittent claudication (a tight, aching, or squeezing pain in the calf, foot, thigh, or buttock that occurs during exercise).

You also may be asked about behaviors, habits, and physical traits that may be related, such as:

• Smoking.
• Lack of regular, moderate exercise.
• Being overweight and having a high body mass index.

You may also have tests to check for other diseases or health conditions—such as diabetes, peripheral neuropathy, pregnancy, kidney problems, or iron deficiency anemia—that can cause your symptoms. Tests will vary depending on what your doctor identifies as likely problems.