Influence of task on interlimb coordination in adults with cerebral palsy

Abstract

Objective: To examine movement time and kinematic properties of unilateral and bilateral reaching movements in adults with cerebral palsy (CP), focusing on how different types of bilateral movements, simultaneous or sequential, may influence interlimb coordination.

Design: Quantitative study using between-group repeated-measures analyses.

Setting: Motor control laboratory at a research university.

Participants: Adults with hemiplegic CP (n=11; mean age ± SD, 33±10y; 4 men) and age-matched controls (mean age ± SD, 32±9y; 4 men).

Interventions: Not applicable.

Main outcome measures: Movement time (MT), maximum deviation from a straight trajectory to the target, and peak speed.

Results: Although adults with hemiplegic CP showed strong unilateral deficits, bilateral simultaneous reaching movements were temporally and spatially coupled. Movement of the less affected arm slowed to match the movement of the more affected arm. In contrast, bilateral sequential movements improved MTs of the less affected and more affected arms.

Conclusions: Bilateral sequential movements were conducive to faster MT compared with unilateral or bilateral simultaneous movements. Training that includes bilateral sequential movements may be beneficial to adults with hemiplegic CP. Upper-limb movements are coordinated in a variety of ways to perform routine bilateral tasks. Some bilateral tasks, such as stacking boxes, require more symmetric movements of the upper limbs. Other bilateral tasks, such as opening the refrigerator with 1 hand while placing an item on the shelf with the other hand, emphasize coordinated sequential action between upper limbs. Despite the prevalence of integrative upper-limb use, the control of different forms of bilateral movement is not well understood. A more comprehensive knowledge of upper-limb bilateral movements may hold important implications for developing more effective upper-limb movement therapies.

Figure 1

Sample raw data traces of A.) movement of the dominant hand of a control participant, B.) movement of the less affected hand of a participant with stroke, C.) movement of the more affected hand of a participant with stroke. Arrows indicate direction of reaching movement (upward arrow – reach movement, downward arrow – return movement). Abbreviations: LA, less affected; MA, more affected.

Figure 2

Kinematic analyses: A.) Movement time in control group (Mean +1 SE), B.) Movement time in adults with CP. (Mean +1 SE), C.) Maximum deviation in control group (Mean +1 SE), D.) Maximum deviation in adults with CP (Mean +1 SE), E.) Peak speed in control group (Mean +1 SE), F.) Peak speed in adults with CP (Mean +1 SE).