The relation of hand and arm configuration variances while tracking geometric figures in XXXX : aspects for rehabilitation.

@entity1 @entity717 @entity191
Variances of drawing arm movements between @entity1 with @entity191 and healthy controls were compared. The aim was to determine whether differences in joint synergies or individual joint rotations affect the endpoint (hand position) variance. Joint and endpoint coordinates were measured while @entity1 performed drawing tasks. Variances of arm configurations and endpoints were computed and statistically analyzed for 12 @entity1 and 12 controls. The variance of arm movements for @entity1 (both for arm configuration and endpoint) was overall higher than that for the control group. Variation was smaller for drawing a circle versus a square and for drawing with the dominant versus the nondominant hand within both groups. The ratio of arm configuration variances between groups was similar to the ratio of endpoint variances. There were significant differences in the velocity, but not in the path lengths of movements comparing the two groups. @entity1 presented @entity717 stability while drawing different figures in different trials. Moreover, the similarity of the ratios suggests that the ill-coordinated hand movement was caused by the error in the movements of individual body parts rather than by the lack of intersegmental coordination. Thus, rehabilitation may focus on the improvement of the precision of individual joint rotations.
