We compared the effect of visual information on the dominant upper limb position sense of children with diplegic cerebral palsy (n = 10) and normally developing children (n = 10). An isokinetic dynamometer passively moved the dominant forearm in 120° of elbow flexion/extension until the volunteers stopped the machine to indicate that the elbow joint was positioned in the predetermined target angle. Participants performed this task five times in sequence with and without visual feedback of the elbow angle. We calculated the absolute and the relative position errors related to the final elbow position and the target angle. In both groups, absolute error was significantly higher when vision was occluded. Relative error was not affected by cerebral palsy or visual feedback. When vision was occluded, accuracy on this task was similarly impaired in both groups and precision was not disturbed.
Keywords: accuracy; diplegic cerebral palsy; position sense; visual feedback; visual information.