| Home | Publications | Proceedings |
Objectives: This study examines the ability of a novel upper limb therapy device, Driver's Simulation Environment for Arm Therapy (Driver's SEAT), to enable subjects with hemiplegia to initiate and actively engage their paretic limb in a functional bimanual exercise task. Driver's SEAT is a 1 degree of freedom robotic device that incorporates a modified PC-based driving simulator to create simple and motivating steering tasks.
Clinical Relevance: Hemiplegia, a common post-stroke condition affects many of the 400,000 stroke survivors per year in the U.S. Upper extremity return of function of both limbs is important for many activities of daily living. If these preliminary results are confirmed in a larger study, then Driver's SEAT has potential to augment and improve current upper limb therapy.
Research Plan: Via Driver's SEAT, subjects with hemiplegia can focus on steering coordination and their ability to regulate the force effort between their paretic and non-paretic limbs. Regulation of force effort is made possible via our unique split steering wheel design, which allow us to measure the tangential forces applied to the wheel by each limb. Three therapy modes, designed to complement the three main stages of stroke recovery, were implemented. They differ by the level of programmed resistance torque experienced at the wheel by the subject. A subject's ability to successfully complete the road-tracking tasks was coupled to their ability to modify the forces generated on the steering wheel with each limb. The main therapy mode implements a bimanual steering task that constrains the non-paretic limb and encourages the paretic limb to control the road-tracking task. The diagnostic mode does not constrain either limb so both can control the road-tracking task.
Methods: To explore whether the main therapy mode encouraged subjects to increase their paretic limb force output, we studied 8 subjects with hemiparesis (age > 50 years). Each subject performed unilateral and bilateral steering tasks in the three steering modes of Driver's SEAT. Force, position, surface EMGs, and video data were collected.
Results: The study showed that the main therapy mode does enable subjects to more actively engage their paretic limb. The level of torque output from paretic limb was greater in the main therapy mode than in the diagnostic mode. These findings support our hypothesis that in a bimanual task without constraints, i.e. our diagnostic mode, subjects with hemiplegia will choose to use their non-paretic limb over their paretic limb to control the outcome of the task but in a bimanual task with constraint, ie the main therapy mode, they would be motivated to switch to their paretic limb as the primary controller of the task.
Conclusions: Subjects with hemiplegia can be encouraged to modify their bilateral force efforts using Driver's SEAT.
Acknowledgments: This project was supported by VA Rehabilitation R&D;Grant B2257PA and NASA Grant No. 2-52208.