Investigators have demonstrated that a variety of intensive movement training protocols for persistent upper limb paralysis in patients with chronic stroke (6 months or more after stroke) improve motor outcome. This randomized controlled study determined in patients with upper limb motor impairment after chronic stroke whether movement therapy delivered by a robot or by a therapist using an intensive training protocol was superior. Robotic training (n = 11) and an intensive movement protocol (n = 10) improved the impairment measures of motor outcome significantly and comparably; there were no significant changes in disability measures. Motor gains were maintained at the 3-month evaluation after training. These data contribute to the growing awareness that persistent impairments in those with chronic stroke may not reflect exhausted capacity for improvement. These new protocols, rendered by either therapist or robot, can be standardized, tested, and replicated, and potentially will contribute to rational activity-based programs.Key Words: Stroke-Recovery of function-Rehabilitation. S troke causes permanent disability that is dependent in large part on motor impairment, and although most patients walk independently, often with a device or orthosis, recovery of arm and hand function occurs less often.1-3 Despite the tendency to focus restorative treatments in the weeks soon after the stroke inasmuch as motor improvements, in general, plateau 3 to 6 months later, 4,5 a new convergence of animal and human studies has focused on the treatment efficacy of repetitive exercise of the paralyzed upper limb to alter motor performance in patients with chronic stroke.5-13 These emerging data have stimulated the clinical development of activity-based techniques based on a combination of the control of guidance and speed of the movements and intensive practice.14-19 In patients with chronic stroke referred to an outpatient clinic, we have attempted to establish a standard therapistdelivered intensive physical therapy program, and then to compare it to a treatment with a robotic-driven protocol that has been demonstrated to alter motor performance significantly in patients with chronic stroke. 15 METHODS Study Population and DesignWe screened 55 patients with stroke referred to the outpatient clinic and who had impaired arm and hand mobility for at least 6 months. Twenty-one patients who met the inclusion criteria were randomized to robotic training that was identical to a past robotic trial 15 or to an intensive upper extremity movement-based treatment from a therapist. The therapist's protocol was designed by a group of senior therapists working in the stroke recovery program, and represented a combination of common practice treatments that, for the purpose of this experiment, matched the session duration, number, and timing of robot treatments. Patients were measured monthly for 3 months to test whether there was spontaneous improvement. Measurements of motor impairment were also obtained at the mid-point and the end of trai...

Thirty patients with chronic stroke received 6 weeks of sensorimotor robotic training in a pilot study that targeted motor function of the affected shoulder and elbow. The impairment and disability scores were stable during a 2-month observation/measurement period, improved significantly by program completion, and remained robust in the 3-month follow-up. Task-specific motor training attenuated a chronic neurologic deficit well beyond the expected period for improvement after stroke.

A system for electromyographic (EMG) triggering of robot-assisted therapy (dubbed the EMG game) for stroke patients is presented. The onset of a patient's attempt to move is detected by monitoring EMG in selected muscles, whereupon the robot assists her or him to perform point-to-point movements in a horizontal plane. Besides delivering customized robot-assisted therapy, the system can record signals that may be useful to better understand the process of recovery from stroke. Preliminary experiments aimed at testing the proposed system and gaining insight into the potential of EMG-triggered, robot-assisted therapy are reported.