A Robotic Neck Exoskeleton for Children with Poor Head Control: A Feasibility Study

Background: color{black}The ability to properly orient the head is essential for learning motor and cognitive skills in child development. Children with severe motor disabilities often struggle to hold their head upright and move it in a controlled manner. Existing solutions, such as passive head equipment and physical therapy, are limited and insufficient. We recently developed a robotic neck exoskeleton to support the head and control its three-dimensional movements. As a first step, this study evaluated the feasibility of using this system in a school environment with children who have poor head control and quantified immediate biomechanical changes in head kinematics and neck muscle activation during an active task. Methods: Five children with poor head control attending the Kauri Sue Hamilton School in Riverton, Utah, participated in this study. While wearing the neck exoskeleton, each child performed a visual tracking task, which required active head twisting to follow a moving target. The device applied a virtual force-field around the head to maintain an upright pose. Four levels of force-field support were tested. Head kinematics and bilateral sternocleidomastoid activity were recorded. Results: The neck exoskeleton was well-fit and well-tolerated by all participants. During use, the system behaved as expected, applying a virtual force-field that resisted deviations from the upright head pose. Stronger force-field support improved head control and task performance. Across conditions, the contribution of head twist to the overall head rotation increased from 40.4% in the zero-torque mode to 65.3%, 66.7%, and 66.5% in the low, medium, and high support levels, indicating more targeted head motion with greater assistance. Despite reduced overall head rotation, mean sternocleidomastoid activation remained substantial across conditions, and activation per degree head rotation increased (from 2.8%\((/^\circ)\) to 12.8%\((/^\circ)\)), suggesting that participants remained actively engaged even when producing smaller movements. Conclusion: This study represents the first evaluation of a robotic neck exoskeleton for improving head control in children with severe motor disabilities. The results validate the use of the robotic system in this population and reveal its effects on immediate biomechanical changes of head control while interacting with the device. These findings provide foundational evidence to justify future longitudinal studies aimed at developing novel robotic interventions to improve head control.