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Professional Technical IVT

periodic limb movement disorder

Also written as: PLMD — periodic limb movement disorder

Sleep disorder characterized by repetitive, involuntary leg movements during sleep that cause significant sleep disruption or daytime impairment.

Full Definition

Periodic limb movement disorder (PLMD) involves repetitive, stereotyped leg movements during sleep that occur in sequences lasting from minutes to hours. These movements typically consist of dorsiflexion of the foot and flexion of the knee and hip, occurring every 20-40 seconds. PLMD is diagnosed when the periodic limb movement index exceeds 15 per hour in adults (5 per hour in children) and is associated with clinically significant sleep disturbance or daytime symptoms. The condition is distinguished from restless legs syndrome by the absence of conscious sensory symptoms and the purely nocturnal occurrence of symptoms.

Usage

Usage note: Distinguish from 'periodic limb movements of sleep' (PLMS), which refers to the movements themselves rather than the disorder.

In Context

  • "Polysomnography revealed periodic limb movement disorder with an index of 45 movements per hour." — Sleep study diagnosis
  • "The patient's bed partner reported frequent leg jerking consistent with periodic limb movement disorder." — Sleep history documentation

Also known as

PLMD nocturnal myoclonus

Don't confuse with

restless legs syndrome periodic limb movements of sleep

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