Task-Oriented Training by a Personalized Electromyography-Driven Soft Robotic Hand in Chronic Stroke: A Randomized Controlled Trial.

BACKGROUND: Intensive task-oriented training has shown promise in enhancing distal motor function among patients with chronic stroke. A personalized electromyography (EMG)-driven soft robotic hand was developed to assist task-oriented object-manipulation training effectively. Objective. To compare the effectiveness of task-oriented training using the EMG-driven soft robotic hand. METHODS: A single-blinded, randomized controlled trial was conducted with 34 chronic stroke survivors. The subjects were randomly assigned to the Hand Task (HT) group (n = 17) or the control (CON) group (n = 17). The HT group received 45 minutes of task-oriented training by manipulating small objects with the robotic hand for 20 sessions, while the CON group received 45 minutes of hand-functional exercises without objects using the same robot. Fugl-Meyer assessment (FMA-UE), Action Research Arm Test (ARAT), Modified Ashworth Score (MAS), Box and Block test (BBT), Maximum Grip Strength, and active range of motion (AROM) of fingers were assessed at baseline, after intervention, and 3 months follow-up. The muscle co-contraction index (CI) was analyzed to evaluate the session-by-session variation of upper limb EMG patterns. RESULTS: The HT group showed more significant improvement in FMA-UE (wrist/hand, shoulder/elbow) compared to the CON group (P < .05). At 3-month follow-up, the HT group demonstrated significant improvements in FMA-UE, ARAT, BBT, MAS (finger), and AROMs (P < .05). The HT group exhibited a more significant decrease in muscle co-contractions compared to the CON group (P < .05). CONCLUSIONS: EMG-driven task-oriented training with the personalized soft robotic hand was a practical approach to improving motor function and muscle coordination. CLINICAL TRIAL REGISTRY NAME: Soft Robotic Hand System for Stroke Rehabilitation. CLINICAL TRIAL REGISTRATION-URL: https://clinicaltrials.gov/. UNIQUE IDENTIFIER: NCT03286309.

Probabilistic Model-Based Learning Control of a Soft Pneumatic Glove for Hand Rehabilitation.

OBJECTIVE: Stroke survivors are usually unable to perform activities of daily living (ADL) independently due to loss of hand functions. Soft pneumatic gloves provide a promising assistance approach for stroke survivors to conduct ADL tasks. However, few studies have explored effective control strategies for the 'human-soft robot' integrated system due to challenges in the nonlinearities of soft robots and uncertainties of human intentions. Therefore, this work aims to develop control approaches for the system to improve stroke survivors' hand functions. METHODS: Firstly, a soft pneumatic glove was utilized to aid with stroke-impaired hands. Secondly, a probabilistic model-based learning control approach was proposed to overcome the challenges. Then a task-oriented intention-driven training modality was designed. Finally, the control performance was evaluated on three able-bodied subjects and three stroke survivors who attended 20-session rehabilitation training. RESULTS: The proposed approach could enable the soft pneumatic glove to provide adaptive assistance for all participants to accomplish different tasks. The tracking error and muscle co-contraction index showed decreasing trends while the hand gesture index showed an increasing tendency over training sessions. All stroke survivors showed improved hand functions and better muscle coordinations after training. CONCLUSION: This work developed a learning-based soft robotic glove training system and demonstrated its potential in post-stroke hand rehabilitation. SIGNIFICANCE: This work promotes the application of soft robotic training systems in stroke rehabilitation.

Effects of a Soft Robotic Hand for Hand Rehabilitation in Chronic Stroke Survivors.

OBJECTIVES: Soft robotic hands are proposed for stroke rehabilitation in terms of their high compliance and low inherent stiffness. We investigated the clinical efficacy of a soft robotic hand that could actively flex and extend the fingers in chronic stroke subjects with different levels of spasticity. METHODS: Sixteen chronic stroke subjects were recruited into this single-group study. Subjects underwent 20 sessions of 1-hour EMG-driven soft robotic hand training. Training effect was evaluated by the pre-training and post-training assessments with the clinical scores: Action Research Arm Test(ARAT), Fugl-Meyer Assessment for Upper Extremity(FMA-UE), Box-and-Block test(BBT), Modified Ashworth Scale(MAS), and maximum voluntary grip strength. RESULTS: For all the recruited subjects (n = 16), significant improvement of upper limb function was generally observed in ARAT (increased mean=2.44, P = 0.032), FMA-UE (increased mean=3.31, P = 0.003), BBT (increased mean=1.81, P = 0.024), and maximum voluntary grip strength (increased mean=2.14 kg, P < 0.001). No significant change was observed in terms of spasticity with the MAS (decreased mean=0.11, P = 0.423). Further analysis showed subjects with mild or no finger flexor spasticity (MAS<2, n = 9) at pre-training had significant improvement of upper limb function after 20 sessions of training. However, for subjects with moderate and severe finger flexor spasticity (MAS=2,3, n = 7) at pre-training, no significant change in clinical scores was shown and only maximum voluntary grip strength had significant increase. CONCLUSION: EMG-driven rehabilitation training using the soft robotic hand with flexion and extension could be effective for the functional recovery of upper limb in chronic stroke subjects with mild or no spasticity.

Soft Rehabilitation Actuator With Integrated Post-stroke Finger Spasticity Evaluation.

Strokes cause severe impairment of hand function because of the spasticity in the affected upper extremities. Proper spasticity evaluation is critical to facilitate neural plasticity for rehabilitation after stroke. However, existing methods for measuring spasticity, e.g. Modified Ashworth Scale (MAS), highly depends on clinicians' experiences, which are subjective and lacks quantitative details. Here, we introduce the first rehabilitation actuator that objectively reflects the condition of post-stroke finger spasticity. The actuator is 3D printed with soft materials. By considering the finger and the actuator together, the spasticity, i.e. stiffness, in finger is obtained from the pressure-angle relationship. The method is validated by simulations using finite element analysis (FEA) and experiments on mannequin fingers. Furthermore, it is examined on four stroke subjects and four healthy subjects. Results show the finger stiffness increases significantly from healthy subjects to stroke subjects, particularly those with high MAS score. For patients with the same MAS score, stiffness variation can be a few times. With this soft actuator, a hand rehabilitation robot that may tell the therapeutic progress during the rehabilitation training is readily available.

Verification of Finger Joint Stiffness Estimation Method With Soft Robotic Actuator.

Stroke has been the leading cause of disability due to the induced spasticity in the upper extremity. The constant flexion of spastic fingers following stroke has not been well described. Accurate measurements for joint stiffness help clinicians have a better access to the level of impairment after stroke. Previously, we conducted a method for quantifying the passive finger joint stiffness based on the pressure-angle relationship between the spastic fingers and the soft-elastic composite actuator (SECA). However, it lacks a ground-truth to demonstrate the compatibility between the SECA-facilitated stiffness estimation and standard joint stiffness quantification procedure. In this study, we compare the passive metacarpophalangeal (MCP) joint stiffness measured using the SECA with the results from our designed standalone mechatronics device, which measures the passive metacarpophalangeal joint torque and angle during passive finger rotation. Results obtained from the fitting model that concludes the stiffness characteristic are further compared with the results obtained from SECA-Finger model, as well as the clinical score of Modified Ashworth Scale (MAS) for grading spasticity. These findings suggest the possibility of passive MCP joint stiffness quantification using the soft robotic actuator during the performance of different tasks in hand rehabilitation.

Simultaneous enlargement of the pulmonary annulus and the pulmonary cusp with autologous pericardium in right ventricular outflow tract reconstruction.

BACKGROUND: Surgical repair of obstructive lesions of the right ventricular outflow tract (RVOT) commonly creates pulmonary valve incompetence, which continues to stimulate research for the optimal materials and surgical techniques to reconstruct RVOT. In this study, we present the early results with simultaneous enlargement of the pulmonary annulus and the pulmonary cusp with a transannular patch of autologous pericardium in RVOT reconstruction. PATIENTS AND METHODS: From January 2003 to December 2005, the surgical technique of simultaneous enlargement of the pulmonary annulus and the pulmonary cusp was used in 32 patients who had complex congenital heart anomalies with pulmonary artery hypoplasia. The functional status of the patients was followed up in the cardiologic clinic of our institute. The motion of the newly constructed valve and the degree of pulmonary insufficiency were evaluated by echocardiography before discharge and at 2-6 months, 12 months, and 36 months postoperatively. RESULTS: Early death occurred in one patient (3.1%). Postoperative complications occurred in six patients but they recovered uneventfully. During the follow-up, 28 of 31 operative survivors were in New York Heart Association functional class I without medication and the other three were in class II. Seventeen patients had no or trivial pulmonary regurgitation; mild regurgitation was present in 12 patients, and moderate regurgitation was seen in 2 patients. None of these patients needed reoperation and echocardiography showed good motion of the reconstructed valve. CONCLUSIONS: The surgical technique of simultaneous enlargement of the pulmonary annulus and the pulmonary cusp with a transannular patch of autologous pericardium is a safe, reliable, and effective way for RVOT reconstruction. Satisfactory early results have been achieved; however, long-term follow-up is necessary to determine the true value of this technique.