Rhythmic movement disorder

Patients with rhythmic movement disorder can present with complaints of repetitive movements that occur before sleep onset.49 The movements are stereotyped, involving large muscles, usually of the head and neck, and are sustained into light sleep. Movements may include head banging, body rocking, leg rolling, humming, and chanting. Some patients are relatively unaware of the movement, and others describe the movement as a calming effect or a compulsion before sleep.

This behavior is frequently seen in infants and young children, and the prevalence diminishes with age. It is more commonly seen in individuals with mental handicaps or autism and is more prevalent in men. Emotional stress may provoke the movements.

Typical episodes are seen on polysomnography as episodes of rhythmic movement preceding sleep onset and during stage 1 sleep, although rhythmic movement disorder can occur out of any stage of sleep.

Sleep bruxism

Sleep bruxism can occur as a rhythmic or repetitive movement during sleep.22,50 Grinding or clenching of the teeth during sleep may produce bizarre sounds, and patients rarely can even vocalize with the episodes. Patients may have abnormal wear of the teeth, jaw pain, headache, facial pain, or tooth pain. They may have hundreds of events per night, and the events increase with emotional stress.

Some studies suggest as many as 85% of the population grinds its teeth to some degree.22 These events usually begin in the teen years. Occasionally a familial pattern can be ascertained.

The polysomnogram demonstrates repetitive bouts of increased temporalis muscle activity, particularly occurring before sleep onset and continuing through stage 2 sleep.

Patients should have a dental evaluation and be considered for bite plates.

Adapted from: Malow, BA, and Vaughn BV. Sleep disorders and epilepsy. In: Ettinger AB and Devinsky O, eds. Managing epilepsy and co-existing disorders. Boston: Butterworth-Heinemann; 2002;255–267.
With permission from Elsevier (www.elsevier.com).
Reviewed and revised April 2004 by Steven C. Schachter, MD, epilepsy.com Editorial Board.