Motor ability and visual-motor integration in children affected by tic disorder

Background: By previous studies it has been observed that patients with Tourette Syndrome (TS) present deficits in visual-motor integration, fine motor skill and spatial/motor ability. More recently, it has been suggested that fine motor skill deficits may be predictors of future tic severity and global psychosocial functioning in TS children. Objective: We hypothesized that deficits of motor coordination could be present in a large number of children with Tic Disorders (TD) and this could constitute a further source of social impairment. With this purpose, we performed a cross sectional evaluation of motor coordination and visual-motor integration in a large group of TD children. Methods: Our sample was constituted by 96 TD children (19 females, 77 males) with an age ranged between 4 and 13 years. 18 children presented a diagnosis of Transient Tics, 16 of Chronic Multiple Motor or Phonic Tics and 62 of Tourette Syndrome. Exclusion criteria were the presence of a diagnosis of mental retardation or autistic spectrum disorder; all patients were drug naive.Patients underwent a focused neuropsychological testing battery of Movement Assessment Battery for Children (M-ABC)and Beery-Buktenica Developmental Test of Visual-Motor Integration (VMI). Results: We have observed, in a large part of our sample, difficulties in motor ability. 19% of children obtained pathological scores (inferior to the 5th percentile) on the total M-ABC and another 17% achieved borderline scores (between the 5th and 15th percentile); the higher rate of impairment was found in the manual dexterity subtests (33% had pathological scores and 22% borderline scores).No association was found between the categorical M-ABC total scores (categorized as normal/borderline/pathologic, or grouping together borderline and pathologic) and TD diagnosis or tic severity measured by YGTSS. Children with higher YGTSS scores tended to show poorer performances in M-ABC, in particular on the manual dexterity sub-items, but the correlation did not reach a statistical significance. Conclusions: Our results confirmed the clinical impression that many children with TD are clumsy. In further study, two aspects deserve to be expanded, the developmental trajectories of children showing poor motor performance and the relationship of motor disabilities with other problems (ADHD, learning disabilities) that impair a large set of children affected by TD.