What is periodic limb movement disorder?
Periodic limb movement disorder (PLMD) is repetitive cramping or jerking of the legs during sleep. Periodic limb movement disorder is one of the commonest neurological disorders and causes significant disability, if left untreated. However, it is rarely diagnosed in clinical practice, probably due to lack of awareness and/or lack of necessary diagnostic
facilities. Restless leg syndrome (RLS), aging, pregnancy, uraemia, iron deficiency, polyneuropathy are some of the common causes of secondary PLMD.
Periodic limb movement disorder is characterized by repetitive limb movements that occur during sleep. These episodes of limb movement disrupt sleep, causing insomnia or daytime sleepiness. Periodic limb movement symptoms are only considered a disorder (PLMD) when insomnia or daytime sleepiness cannot be explained by any other problem, such as restless legs syndrome (RLS).
Periodic limb movements of sleep produces quick twitches or kicks of the leg that occur repeatedly during but not before sleep. The limb movements interfere with deep sleep, though the person may not be aware of it and simply feels unrested the next day.
The exact cause of periodic limb movement disorder is unknown. PLMD may occur with other sleep disorders. It is often linked with restless legs syndrome, but they are not the same thing. Restless legs syndrome is a condition involving strange sensations in the legs (and sometimes arms) while awake and an irresistible urge to move the limbs to relieve the sensations. At least 80% of people with restless legs syndrome have PLMD, but the reverse is not true. Although PLMD shares many underlying factors with RLS, such as a hereditary link, iron deficiency anemia, nerve problems, poor blood circulation in the legs, kidney disorders, and others, the two conditions are generally seen as related, not as causing one another.
A person with periodic limb movement disorder has insomnia or daytime sleepiness because the movements disrupt sleep. These movements usually are related to the legs and occur in some type of pattern. Although a person often is not fully awakened by these movements, they interfere with normal sleep cycles. A bed partner's sleep may also be disrupted. In periodic limb movement disorder, the legs and/or arms twitch or jerk at a regular rate (approximately 2-3 times per minute) during sleep. The movements are most frequent during the first half of the night. Some of these movements are associated with sleep disruption.
More information on restless legs syndrome
What is restless legs syndrome? - Restless legs syndrome (RLS) is a condition that produces an intense, often irresistible urge to move the legs caused by or associated with unpleasant feelings in them.
What causes restless legs syndrome? - The cause of restless legs syndrome remains unknown. Restless legs syndrome is a central nervous system disorder. Stress generally makes restless legs syndrome worse.
What're the risk factors for restless legs syndrome? - Risk factors for restless legs syndrome include pregnancy, osteoarthritis, varicose veins, diabetes, iron deficiency anemia, fibromyalgia, rheumatoid arthritis.
What're the complications of restless legs syndrome? - Severe and persistent restless legs syndrome symptoms can cause considerable mental distress, chronic insomnia, and daytime sleepiness.
What're the symptoms of restless legs syndrome? - Restless legs syndrome symptoms are unpleasant or uncomfortable feelings or sensations in the legs often described as creeping, crawling, tingling, pulling.
How is restless legs syndrome diagnosed? - The diagnosis of restless legs syndrome is based primarily on the patient's history. Polysomnography may be used to rule out other sleep disorders.
What's the treatment for restless legs syndrome? - Treatment of restless legs syndrome depends on the severity of symptoms. Medications used to treat restless leg syndrome include carbidopa, levodopa, opioids.
What non-drugs therapies are available? - Exercise may be one of the best ways to achieve healthy sleep. Stimulus control is the standard treatment for primary chronic insomnia. Paradoxical intention is a psychological approach.
What medications cure restless legs syndrome? - Daily drug treatment is recommended only for people who have restless legs syndrome (RLS) symptoms at least three nights a week.
How to prevent restless leg syndrome? - Prevention of sleeplessness is dependent upon the patient's ability to relax. Diet is very important in preventing restless legs syndrome.
What's periodic limb movement disorder? - Periodic limb movement disorder (PLMD) is repetitive cramping or jerking of the legs during sleep.