Effects of Treatment Intensity in Upper Limb Robot-Assisted Therapy for Chronic Stroke: A Pilot Randomized Controlled Trial

Background and Objectives. Robot-assisted therapy (RT) is a current promising intervention in stroke rehabilitation, but more research is warranted for examining its efficacy and the dose-benefit relation. The authors investigated the effects of higher intensity versus lower intensity RT on movements of forearm pronation-supination and wrist flexion-extension relative to conventional rehabilitation (CR) in patients poststroke for a mean of 21 months. Methods. In this pilot study, 18 patients with initial mean Fugl-Meyer Assessment (FMA) of 37 to 44 for the upper extremity were randomized to higher intensity RT, lower intensity RT, or CR intervention for 4 weeks. The dose of the higher intensity RT was twice the number of repetitions in the lower intensity RT. Outcome measures at pretreatment and posttreatment were administered to patients to evaluate beneficial and adverse effects of interventions. Primary outcomes were the FMA and Medical Research Council scale. Results. There were significant differences in motor function (P = .04) and daily performance (P = .03) among the 3 groups. The higher intensity RT group showed better improvement in motor function, muscle strength, performance of daily activities, and bimanual ability than the other 2 groups. The intensive RT intervention did not induce higher levels of an oxidative DNA biomarker. Conclusions. Higher intensity of RT that assists forearm and wrist movements may lead to greater improvement in motor ability and functional performance in stroke patients. A sample size of only 20 to 25 in each arm of a larger randomized controlled trial is needed to confirm the findings for similar subjects.