This study examined body-scaled information that specifies the reach patterns of children with hemiplegic cerebral palsy and children with typical development.
Nine children with hemiplegic cerebral palsy (3-5 years) and 9 age-matched children with typical development participated in the study. They were required to reach and grasp 10 different pairs of cubes. Reach data were coded as either a 1-handed reach or a 2-handed reach. Dimensionless ratios were calculated by dividing the cube size by the maximal aperture between the index finger and thumb. A critical ratio was used to establish the shift from a 1-handed to an exclusive 2-handed reach.
The critical ratio was not significantly different for either preferred or nonpreferred arms within and between groups. All children used an exclusive 2-handed reach at a similar dimensionless ratio.
Our study provides evidence of the “fit” between environment (cube size) and the individual's capabilities (finger aperture) for reaching for both groups.