Comparisons between end-effector and exoskeleton rehabilitation robots regarding upper extremity function among chronic stroke patients with moderate-to-severe upper limb impairment

Abstract

Background and purpose: Many rehabilitation robots are now available for post-stroke upper limb training, and are generally categorized into end-effector (EE) and exoskeleton (Exo) types. Two types of rehabilitation robots, EE and Exo robots have not been directly compared previously. The present study aimed to directly compare EE and Exo robots in a selected population of chronic stroke patients with moderate-to-severe upper limb impairment.

Methods: This single-blinded, controlled trial included 38 patients with stroke who were admitted to the rehabilitation hospital. Participants were equally divided into EE and Exo groups. Baseline characteristics of the participants, including sex, age, stroke type, brain lesion side (left or right), stroke duration, Fugl–Meyer Assessment (FMA)–Upper Extremity score, and Wolf Motor Function Test (WMFT) score, were assessed. Additionally, impairment level (FMA, motor status score), activity (WMFT), and participation (stroke impact scale [SIS]) were evaluated. Participants received 30 minutes of therapy 5 days a week for 4 weeks, making a total of 20 sessions of robot-assisted therapy, along with conventional occupational therapy for the same dosage. Assessments were done four times: at baseline, after 4 weeks of the intervention, 4 weeks after the end of the intervention and 6 weeks after the end of the intervention.

Results: There were no significant differences in baseline characteristics, including the baseline primary outcome measures, between the EE and Exo groups. After the robot intervention, improvements were significantly better in the EE group than in the Exo group with regard to activity and participation (WMFT–Functional ability rating scale, WMFT–Time, and SIS–Social participation). There was no adverse event related to the intervention.

Conclusion: The EE robot intervention resulted better than the Exo robot intervention with regard to activity and participation among chronic stroke patients with moderate-to-severe impairment of upper extremity function. This study has limitation of only including chronic stroke patients with moderate-to-severe limb impairment, and further studies are needed.