A proof of concept study for the integration of robot therapy with physiotherapy in the treatment of stroke patients

Objective: To carry out a proof of concept study for integrating robot therapy with physiotherapy in the treatment of stroke patients. Design: A simple and `gentle' paradigm of robot—patient interaction was designed in order to foster the re-emergence of smooth, active control patterns in coordinated shoulder/elbow reaching movements. A haptic robot was programmed according to a strategy of minimal, progressively reduced assistance, with a double representation of targets: (i) visual (circles on a screen) and (ii) haptic (robot-generated force fields). The protocol included trials with and without vision, in order to emphasize the role of proprioceptive feedback. The training paradigm included 10 sessions and more than 5000 movements. Subjects: Ten chronic, hemiparetic subjects; four controls provided reference values for the performance measurements. Outcome measures: Four performance indicators (derived from the analysis of the reaching trajectories); clinical/functional measures (Fugl-Meyer and Ashworth scales). Results: After robot therapy reaching movements became faster and smoother. The performance in the no-vision trials was at least as good as in the vision trials. The Fugl-Meyer arm scores also increased significantly and remained approximately constant at follow-up; the Ashworth scores did not change. Conclusion: In spite of its simplicity, a limited number of `gentle' robot therapy sessions appear to be beneficial, even for severely impaired patients, although no firm conclusion can be drawn at this point. However, the study provides support material for the careful design of controlled clinical trials and for a better integration with physiotherapy.