Developmental delay of finger torque control in children with developmental coordination disorder.
OBJECTIVE
We examined whether the behavioral impairments in finger torque control evident in children with developmental coordination disorder (DCD) follow a delayed or different developmental trajectory compared with their typically developing peers.


METHODS
Children with DCD (n=36; 18 males, 18 females; mean age 9y 7mo, SD 1y 8mo) and 36 typically developing children (15 males, 21 females; mean age 9y 7mo, SD 2y), between 6 years 10 months and 12 years 7 months of age were recruited from schools in Porto Alegre, Brazil. Particpants completed finger torque control and maximum finger torque production tasks. The inclusion criterion for children with DCD was a Movement Assessment Battery for Children score below the fifth centile. Group means and cross-sectional age-related landscapes of the two groups were compared.


RESULTS
Children with DCD were more variable (p<0.001), less accurate (p=0.007), and less irregular (p<0.001), on average, in their finger torque control than their typically developing peers, despite producing nearly equivalent levels of maximum torque (p=0.49). Despite these mean differences, the cross-sectional age-related changes in torque control were similar in the two groups (all p>0.05).


CONCLUSIONS
The developmental trajectory of finger torque control in children with DCD, compared with typically developing children, is delayed. This suggests the behavioral deficits in finger torque control in children with DCD persist as a function of age, rather than progressing or resolving.
Cognitive Motor Neuroscience Laboratory, Department of Kinesiology, University of Maryland, College Park, MD, USA.
Bradley R
BR
King
Jane E
JE
Clark
Marcio A
MA
Oliveira
D000367:Age Factors; D002648:Child; D003430:Cross-Sectional Studies; D002658:Developmental Disabilities / Q000175:diagnosis*; D005260:Female; D005385:Fingers; D018737:Hand Strength; D006801:Humans; D007537:Isometric Contraction; D008297:Male; D008838:Microcomputers; D019957:Motor Skills Disorders / Q000175:diagnosis*; D012016:Reference Values; D012815:Signal Processing, Computer-Assisted; D019415:Torque