Impact of initial flexor synergy pattern scores on improving upper extremity function in stroke patients treated with...

Background: Robot-assisted rehabilitation is an appealing strategy for patients after stroke, as it generates repetitive movements in a consistent, precise, and automated manner. Objective: To identify patients who will benefit most from robotic rehabilitation for upper extremity (UE) hemiparesis. Methods:We used data from our previous randomized clinical trial comparing 6 weeks of robotic therapy (ReoGeo system) plus standard therapy (n=30) with self-guided therapy plus standard therapy (n=26) for sub-acute phase rehabilitation in adults with mild to moderate UE hemiparesis. The outcome measures were three Fugl-Meyer (FMA) motor scores: total UE score, proximal UE score, and UE flexor synergy score. Based on pre-therapy UE flexor synergy scores, participants were categorized into mild (10-12 points), moderate (6-9 points), and severe (0-5 points) impairment classes. Results: In the robotic group, all outcome measures improved after therapy in patients with moderate or severe impairment. In the self-guided therapy, most outcomes did not improve, regardless of the impairment class. When changes from pre- to post-therapy were compared between robotic and self-guided groups, most outcomes were similar in all impairment classes. However, robotic therapy was associated with greater improvement in UE flexor synergy than self-guided therapy in patients with moderate impairment (2.3±1.3 vs. -0.1±2.8, P=0.027). Conclusions: Post-strokerobot-assisted rehabilitation, as an adjunct to standard rehabilitation therapy, improved UE function in patients with moderate or severe pre-therapy UE flexor synergy impairment. Adjunct robotic therapy produced greater improvement in UE flexor synergy motor function than adjunct self-guided rehabilitation in patients with moderate pre-therapy impairment.