Wrist position sense acuity and its relation to motor dysfunction in children with developmental coordination disorder.

This study obtained objective measures of wrist position sense to verify that children with DCD have proprioceptive deficits. In addition, it examined the relationship of wrist proprioceptive impairment with fine motor and balance function. Twenty children with DCD and thirty typically developing children (TD) aged 10-11 years old were recruited and screened using the Movement Assessment Battery for Children (MABC-2). The DCD group had total MABC-2 score below 5th percentile, and TD group was above 25th percentile. Wrist position sense was assessed under two conditions: 1) an ipsilateral wrist joint position matching requiring active movement to reproduce a reference position, and 2) a psychophysical discrimination threshold testing, in which the wrist joint was passively rotated. The results showed that, in comparison to TD controls, the DCD group showed an increased joint position error variability during active matching (p < 0.05) and highly elevated mean position sense threshold for passive displacement (+71%; p < 0.001). Position sense threshold data correlated significantly with manual dexterity (r = -0.4) and balance scores (r = -0.5). This study documents that DCD is associated with a proprioceptive dysfunction of the wrist/hand complex, which likely contributes to the fine motor problems in children with DCD.