Sensory and Motor Parameters Predict Performance on the Bead Maze Hand Function Test

Understanding the forces imparted onto an object during manipulation can shed light on the quality of daily manual behaviors. We have developed an objective measure of the quality of hand function in children, the Bead Maze hand function test, which quantifies how well the individual performs the activity by integrating measures of time and force control. Our main objectives were to examine associations between performance (total force output) on the Bead Maze Hand Function test and 1) performance on a sensitive measure of force scaling obtained on a laboratory-based dexterous manipulation task, and 2) general sensory and motor parameters important for fine motor skills. Thirty-nine typically developing participants ranging in age from 5-10 years old (n=28) and 15-17 years (n=11). Force, completion time, and movement of sensorized objects were recorded, along with hand size, strength, and sensory measures. We found that better performance on the Bead Maze Hand Function test can be predicted by the development of anticipatory coordination of digit forces. We also found that factors of hand size and strength known to improve with age in typically developing children were associated with improved Bead Maze performance, and that pinch strength improved our ability to predict total force on the double curve wire. These findings support the integration of more sensitive sensorimotor metrics, such as the total applied force, into clinical assessments. Connecting the development of sensorimotor capabilities to functional task performance can facilitate more targeted and effective intervention strategies, ultimately improving a child’s participation in daily activities.