Childhood-Onset Movement Disorders: A Clinical Series of 606 Cases.

The aim of this work is to report the distribution of clinical phenomenology, demographic variables, and delay of diagnosis in a cohort of patients with childhood-onset movement disorders. Personally examined patients with childhood-onset movement disorders apart from those with cerebral palsy are reported. A total of 606 patients were included. The majority had tic disorders (346; 57%) followed by dystonia (72; 12%); other movement disorders were less frequent (<5%). Mean onset age of patients with tics was 7.4 years ± 3.8 standard deviation; mean delay of diagnosis was 9.9 ± 11 years. Mean onset age of other movement disorders was 8.6 ± 5.7 years; mean delay of diagnosis was 11.1 ± 12.5 years. Psychogenic movement disorders had a later onset than all other movement disorders (P < 0.01) apart from tremor and "other movement disorders." Dystonias had a longer delay of diagnosis than psychogenic movement disorders (P < 0.038). The diagnostic delay of childhood-onset movement disorders is considerable, indicating that they are probably under-recognized.