Benign and periodic movement disorders in 2 children with Down syndrome.

Children with Down syndrome show hypotonia and ligamentous laxity that are associated with motor development delay. Neurologic disorders are common in children with Down syndrome; however, in literature the presence of periodic movement disorders has not yet been described. We report 2 different types of periodic movement disorders in 2 infants with Down syndrome. In the first case, we described an 8-month-old girl with involuntary head nodding and absence of any other neurologic or ophthalmologic abnormalities. In the second case, we described a 6-month-old boy with abnormal but painless head rotation and inclination, alternating from side to side. Episodes of head tilting were often associated with a state of general uneasiness. Neurologic examination between attacks was normal. The aim of this paper is to provide practical information on recognition and management of movement disorders in Down syndrome.