Clinical features and long-term outcomes of 100 children (62 boys and 35 girls) with motor stereotypies were evaluated by review of records and telephone interviews at Johns Hopkins Hospital, Baltimore, MD. Mean age was 8.3 +/- 4.5 years. Age at onset was < 24 months in 81%. All children were in a regular classroom and were at least grade C in achievement. Six had a history of early language delay. Repetitive, rhythmic, involuntary movements consisted of finger wiggling and/or flapping of hands or arms; 20% also exhibited facial grimacing, and 8% had head nodding movements. Movements occurred once a day or more in 90% and lasted less than a minute in 62%. Triggers included excitement/happiness in 80%, anxiety and stress in 26%, and fatigue in 21%. Stereotypies ceased during sleep and when cued by calling his or her name. Family history was positive for most motor stereotypies in 17% first-degree relatives, but negative in patients with head nodding. Associated conditions included ADHD in 30%, tics in 18%, and OCD in 10%. Various medications prescribed in 20 patients, including clonidine, risperidone, and oxcarbazepine, were ineffective, and behavior modification in 14 resulted in modest improvements in 5 patients. Follow-up ranged from 2 months to 26 years, with a median of 6 years. Movements were persistent in 94 children, continuing for >10 years in 22%, and 6-10 years in 44%. Prognosis was better in children with head nodding than in those with hand/arm movements; head nodding resolved in one third, compared to only 3% with hand movements (P=0.001). 
COMMENT. The present findings in 100 patients are similar to those reported in a previous study of 40 patients from the same institution (Ped Neur Briefs Sept 2004; 18:72) . Most motor stereotypies are chronic and persistent and of greater concern to parents and physicians than to the child. Approximately 50% of patients with motor stereotypies >7 years of age have a comorbid disorder such as ADHD, tics or OCD.
Motor stereotypies are defined as involuntary, bilateral, repetitive, rhythmic movements associated with periods of excitement, stress, and fatigue . They are common in mentally retarded and autistic children, and less prevalent in otherwise normal, healthy children. Associated disorders such as tics are distinguished by a later age of onset, 5-10 years, their asymmetry, vocal as well as motor, and response to medication.