Robotic unilateral and bilateral upper-limb movement training for stroke survivors afflicted by chronic hemiparesis

Stroke is the leading cause of long-term neurological disability and the principle reason for seeking rehabilitative services in the US. Learning based rehabilitation training enables independent mobility in the majority of patients post stroke, however, restoration of fine manipulation, motor function and task specific functions of the hemiplegic arm and hand is noted in fewer than 15% of the stroke patients. Brain plasticity is the innate mechanism enabling the recovery of motor skills through neurological reorganization of the brain as a response to limbs´ manipulation. The objective of this research was to evaluate the therapeutic efficacy for the upper limbs with a dual arm exoskeleton system (EXO-UL7) using three different modalities: bilateral mirror image with symmetric movements of both arms, unilateral movement of the affected arm and standard care. Five hemiparetic subjects were randomly assigned to each therapy modality. An upper limb exoskeleton was used to provide bilateral and unilateral treatments. Standard care was provided by a licensed physical therapist. Subjects were evaluated before and after the interventions using 13 different clinical measures. Following these treatments all of the subjects demonstrated significant improved of their fine motor control and gross control across all the treatment modalities. Subjects exhibited significant improvements in range of motion of the shoulder, and improved muscle strength for bilateral training and standard care, but not for unilateral training. In conclusion, a synergetic approach in which robotic treatments (unilateral and bilateral depending on the level of the motor control) are supplemented by the standard of care may maximize the outcome of the motor control recover following stroke.