A comparison of the effects and usability of two exoskeletal robots with and without robotic actuation for upper extremity rehabilitation among patients with stroke: a single-blinded randomised controlled pilot study

Abstract

Background Robotic rehabilitation of stroke survivors with upper extremity dysfunction may yield different outcomes depending on the robot type. Considering that excessive dependence on assistive force by robotic actuators may interfere with the patient’s active learning and participation, we hypothesised that the use of an active-assistive robot with robotic actuators does not lead to a more meaningful difference with respect to upper extremity rehabilitation than the use of a passive robot without robotic actuators. Accordingly, we aimed to evaluate the differences in the clinical and kinematic outcomes between active-assistive and passive robotic rehabilitation among stroke survivors. Methods In this single-blinded randomised controlled pilot trial, we assigned 20 stroke survivors with upper extremity dysfunction (Medical Research Council scale score, 3 or 4) to the active-assistive robotic intervention (ACT) and passive robotic intervention (PSV) groups in a 1:1 ratio and administered 20 sessions of 30-min robotic intervention (5 days/week, 4 weeks). The primary (Wolf Motor Function Test [WMFT]-score and -time: measures activity), and secondary (Fugl-Meyer Assessment [FMA] and Stroke Impact Scale [SIS] scores: measure impairment and participation, respectively; kinematic outcomes) outcome measures were determined at baseline, after 2 and 4 weeks of the intervention, and 4 weeks after the end of the intervention. Furthermore, we evaluated the usability of the robots through interviews with patients, therapists, and physiatrists. Results In both the groups, the WMFT-score and -time improved over the course of the intervention. Time had a significant effect on the WMFT-score and -time, FMA-UE, FMA-prox, and SIS-strength; group × time interaction had a significant effect on SIS-function and SIS-social participation (all, p < 0.05). The PSV group showed better improvement in participation and smoothness than the ACT group. In contrast, the ACT group exhibited better improvement in mean speed. Conclusions There were no differences between the two groups regarding the impairment and activity domains. However, the PSV robots were more beneficial than ACT robots regarding participation and smoothness. Considering the high cost and complexity of ACT robots, PSV robots might be more suitable for rehabilitation in stroke survivors capable of voluntary movement. Trial registration The trial was registered retrospectively on 14 March 2018 at ClinicalTrials.gov (NCT03465267).

Kinematic Assessment to Measure Change in Impairment during Active and Active-Assisted Type of Robotic Rehabilitation for Patients with Stroke

“…The participants performed reaching tasks to generate three-dimensional trajectory data used for calculating the features. Specific details on rehabilitation training are described by Park et al [15].…”

“…We hypothesized that rehabilitation using two different robots would result in different kinematic changes. Recently, we demonstrated discrepant changes in kinematics between ACT and ACAS, although clinical measurements, including FMA and WMFT, did not find any difference [15]. The purpose of this study was to determine whether the kinematic features that cause changes in FMA differ during rehabilitation with ACT and ACAS robotic rehabilitation.…”

“…ACT should be operated by the user during the training, whereas the active assistive robotic device (ACAS) actively aids in the user's movement. ACAS provides assistive force for the user's movement and helps the user to reach a target point even if he/she is not able to move at all [13][14][15]. The provision of active assisted force of the robot may benefit patients who struggle with spontaneous movement, as the robot can be trained for a desired path or speed.…”

Discussion on the Rehabilitation of Stroke Hemiplegia Based on Interdisciplinary Combination of Medicine and Engineering

“…Thus, researchers have put forward the concept of “assist-as-needed” [ 25 ] which refers to helping patients with rehabilitation exercises with the least assistance, so as not to reduce patient spontaneity and initiative. In contrast to this model, a single-blind randomized controlled trial study showed that passive intervention robots are more effective in the rehabilitation of patients with hemiplegia after stroke, and the cost and complexity of passive intervention robots are lower than those of active intervention robots [ 26 ].…”

Hiding Assistive Robots During Training in Immersive VR Does Not Affect Users’ Motivation, Presence, Embodiment, Performance, Nor Visual Attention

“…For example, healthy adults felt more competent and satisfied in a golf-putting task when assisted by a robot versus when the robot augmented their error [21]. However, excessive assistance might also encourage patients to rely on the assistance and reduce their attention and effort [29,30]. Robotic assistance might also lower the experienced embodiment over an avatar if it reduces the sense of agency -i.e., the experience that oneself is initiating and controlling an external event through one's own actions [31,32].…”