Sleep-related movement disorders

Abstract

Sleep-related movement disorders are conditions characterized by simple and usually stereotyped movements that disturb sleep. They comprise periodic limb movement disorder, nocturnal leg cramps, sleep-related bruxism, sleep-related rhythmic movement disorder, and movement disorders due to drugs or medical conditions. Some of these movements, such as bruxism, might occur during both wakefulness and sleep, but a clear worsening of the symptoms during sleep is necessary in order to include the condition among sleep-related movement disorders. Sleep-related movement disorders may occasionally be present in healthy individuals, but the manifestations must disturb sleep with daytime consequences in order to be classified within this group of disorders. Finally, sleep-related movement disorders must be distinguished from parasomnias, such as sleepwalking or rapid eye movement sleep behavior disorder (RBD), which normally show more complex muscular patterns and behaviors.