ORIGINAL RESEARCH| Volume 102, ISSUE 11, P2074-2082, November 2021

Exoskeleton-Assisted Anthropomorphic Movement Training (EAMT) for Poststroke Upper Limb Rehabilitation: A Pilot Randomized Controlled Trial

  • Ze-Jian Chen
    Department of Rehabilitation Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan

    World Health Organization Cooperative Training and Research Center in Rehabilitation, Wuhan
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  • Chang He
    Institute of Rehabilitation and Medical Robotics, State Key Lab of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology, Wuhan, China
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  • Feng Guo
    Department of Rehabilitation Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan

    World Health Organization Cooperative Training and Research Center in Rehabilitation, Wuhan
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  • Cai-Hua Xiong
    Institute of Rehabilitation and Medical Robotics, State Key Lab of Digital Manufacturing Equipment and Technology, Huazhong University of Science and Technology, Wuhan, China
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  • Xiao-Lin Huang
    Corresponding author Xiao-Lin Huang, PhD, Department of Rehabilitation Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
    Department of Rehabilitation Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan

    World Health Organization Cooperative Training and Research Center in Rehabilitation, Wuhan
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      • Exoskeleton-assisted anthropomorphic movement training generated reaching movements of the upper extremity under human-like postures and trajectories.
      • EAMT therapy provided a novel and feasible method of upper limb robot-assisted training after stroke.
      • Participants may have improved their upper limb motor function, activities of daily living, and kinematics after engaging in the 4-week therapy.
      • There were no differences in motor capacity between the exoskeleton and conventional therapy.
      • The therapy might be effective for moderate to severe motor impairments only in specific training segments as the exoskeleton is focused on the proximal arm.



      To investigate the feasibility of exoskeleton-assisted anthropomorphic movement training (EAMT) and its effects on upper extremity motor impairment, function, and kinematics after stroke.


      A single-blind pilot randomized controlled trial.


      Stroke rehabilitation inpatient unit.


      Participants with a hemiplegia (N=20) due to a first-ever, unilateral, subacute stroke who had a score of 8-47 on the Fugl-Meyer Assessment for Upper Extremity (FMA-UE).


      The exoskeleton group received EAMT therapy that provided task-specific training under anthropomorphic trajectories and postures. The control group received conventional upper limb therapy. For both groups, therapy was delivered at the same intensity, frequency, and duration: 45 minutes daily, 5 days per week, for 4 weeks.

      Main Outcome Measures

      Primary outcome: feasibility analysis. Secondary outcomes: FMA-UE, Action Research Arm Test (ARAT), modified Barthel Index (MBI), and kinematic metrics during exoskeleton therapy.


      Twenty participants with subacute stroke were recruited and completed all therapy sessions. EAMT therapy was feasible and acceptable for the participants. The recruitment rate, retention rate, and number of therapists required for EAMT therapy were acceptable compared with other robotic trials. EAMT was determined to be safe, as no adverse event occurred except tolerable muscle fatigue in 2 participants. There were significant between-group differences in the change scores of FMA-UE (difference, 4.30 points; P=.04) and MBI (difference, 8.70 points; P=.03) in favor of EAMT therapy. No significant between-group difference was demonstrated for the change scores of ARAT (P=.18). Participants receiving EAMT showed significant improvements in kinematic metrics after treatment (P<.01).


      Our results indicate that EAMT is a feasible approach and may improve upper extremity motor impairment, activities of daily living, and kinematics after stroke. However, fully powered randomized controlled trials are warranted to confirm the results of this pilot study and explore the underlying mechanisms by which EAMT therapy might work.

      Key Words

      List of abbreviations:

      ADL (activities of daily living), ARAT (Action Research Arm Test), DOF (degree of freedom), EAMT (exoskeleton-assisted anthropomorphic movement training), FMA-UA (Fugl-Meyer Assessment for Upper Arm), FMA-UE (Fugl-Meyer Assessment for Upper Extremity), FMA-WH (Fugl-Meyer Assessment for Wrist/Hand), MBI (modified Barthel Index), MCID (minimal clinically important difference), PCA (principal component analysis), PE (postural error)
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