Upper limb robot-assisted rehabilitation in sub-acute stroke: Slacking or engagement promotion? Evidence from patient-robot interactions analysis

Abstract

After stroke, interventions based on active repeated movements stimulate neuroplasticity and enhances upper limb motor outcomes. Robotic devices using interactive and adaptive programs offer the ability to perform a large number of movements, including in patients with severe paresis. However, some authors argued that assist-as-needed algorithms would not ensure optimal patient's participation. This retrospective study analyzed robot-patient interactions by measuring motor performance and robotic assistance parameters during robotic sessions. Sixteen patients (age 51 ± 15) with upper limb paresis due to stroke carried out a 16-session robot-assisted training combined with usual care during the sub-acute phase (time from stroke, 43 ± 15 days). The robotic program (5 days a week) comprised at least 2 consecutive series (S1 and S2) of 320 assisted reaching movements performed in the horizontal plane. Time of series completion, active-assisted motor performance (range of motion, accuracy, smoothness) and robotic assistance parameters during movements’ execution were analysed between S1 and S2 every 4 sessions during the training program. Time of 320-movement series completion, robotic assistance and motor performance were not different between S1 and S2 over the training ( Table 1 ). The results indicated that a highly repetitive robot-assisted training for the upper limb can be associated with both sustained active participation and motor performance during robotic sessions. Robotic algorithms might optimize patient's active engagement and motor performance in spite of an unparalleled number of repetitions compared to usual care.