Subject-specific, Impairment-based Robotic Training of Functional Upper Limb Movements

Significant hand and upper-limb impairment is common post-stroke. Robotic training can administer a high-dose of repetitive movement training to stroke survivors, but its efficacy can be further improved by targeting specific impairments of individual patients. In this study, we developed a new robotic training protocol that identifies specific impairment patterns that degrade functional performance of individual patients and provide joint-specific assistance to counteract subject-specific impairments. The target tasks were also adjusted based on their task performance during training. Two chronic stroke survivors participated in a pilot training study to demonstrate the efficacy of the proposed impairment-based robotic training. Upper limb function of the participants was improved by the proposed training as shown in the clinical tests (6.5 ± 4.5 increase in Fugl-Meyer; 10 ± 6.9 increase in Action Research Arm Test), and the laboratory tests also showed improvement in their range of motion (hand) and voluntary reaching distance (arm). The impairment-based robotic training targeted (and improved) specific deficits of individual patients that hampered their task performance, which could have contributed to the observed functional improvement. The proposed training can enhance the rehabilitative outcome of robotic training by emphasizing the key components of effective rehabilitation, i.e., subject-specific, impairment-based training.Clinical Relevance- This study shows that impairment-based, `subject-specific' robotic trainings can improve upper extremity function of stroke survivors.