Pilot testing of the spring operated wearable enhancer for arm rehabilitation (SpringWear)

Effect of exoskeleton manipulator on hand function rehabilitation for postburn patients

PURPOSE

Patients with scar contracture deformities caused by hand burns were treated with an exoskeleton manipulator system, which was equipped with games to explore its clinical application value.

METHODS

Twenty patients who were treated for post-burn scars of bilateral hands between October 2020 and June 2021 were selected (ChiCTR2000036232). The patients were divided into two groups: control, 10 patients (traditional outpatient treatment); and experimental, 10 patients (exoskeleton manipulator system treatment). We compared the change in the total active motion (TAM) value, grip strength, scar improvement, and postoperative pain improvement.

RESULTS

After 3 months of rehabilitation training, the improvement of thumb TAM was 33.80 ± 11.38 ° in the experimental group and 23.2 ± 6.13 ° in the control group. With respect to the index finger TAM, the improvement in the experimental and control groups was 84.50 ± 30.96 ° and 54.80 ± 15.89 °, respectively. The middle finger TAM of the experimental and control groups improved by 86.75 ± 32.85 ° and 60.25 ± 17.97 °, respectively. However, improvement of grip strength, scar score, and pain score were similar between the two groups.

CONCLUSIONS

The exoskeleton manipulator system has excellent effects in improving burned hand joint movement, which is suitable for hand burn patients and has beneficial clinical effects.Implications for rehabilitationExercise is an effective means to improve the hand function of burn patients.The application of mechanical devices in the rehabilitation of burned hands can effectively help patients exercise.The A5 Hand Function Training System is an exoskeleton mechanical device that can exercise the small joints of the hand. It assists patients in using different computer games during treatment.

Design of Spiral-Cable Forearm Exoskeleton to Assist Supination for Hemiparetic Stroke Subjects

We present the development of a cable-based passive forearm exoskeleton that is designed to assist supination for hemiparetic stroke survivors. Our device uniquely provides torque sufficient for counteracting spasticity within a below-elbow apparatus. The mechanism consists of a spiral single-tendon routing embedded in a rigid forearm brace and terminated at the hand and upper-forearm. A spool with an internal releasable-ratchet mechanism allows the user to manually retract the tendon and rotate the hand to counteract involuntary pronation synergies due to stroke. We characterize the mechanism with benchtop testing and five healthy subjects, and perform a preliminary assessment of the exoskeleton with a single chronic stroke subject having minimal supination ability. The mechanism can be integrated into an existing active hand-opening orthosis to enable supination support during grasping tasks, and also allows for a future actuated supination strategy.

Clinical Test of a Wearable, High DOF, Spring Powered Hand Exoskeleton (HandSOME II)

In previous work, we developed an exoskeleton, Hand Spring Operated Movement Enhancer (HandSOME II), that allows movement at 15 hand degrees of freedom (DOF). Eleven separate elastic elements can be added to customize the extension assistance for individuals with impaired hand function. In this pilot study of twelve individuals with stroke, we measured the immediate improvements in range of motion (ROM) and upper extremity function when wearing the device. Index finger ROM was significantly improved at the PIP (p=.01) and DIP joints (p=.026), and the max extension was significantly increased at the MCP (p<.001), PIP (p=.013) and DIP joints (p=.016). The thumb CMC abduction max (p=.017) and CMC flexion/extension ROM also increased (p=.04). In a grip and release task involving various objects, six subjects were unable to complete the tasks without assistance. Across these 6 subjects, 13 of 42 tasks were completed without assistance, while 36 of 42 tasks were completed when wearing HandSOME II. Despite the extension assistance provided by the device, flexion grip force was not statistically decreased. HandSOME II can potentially increase the effectiveness of repetitive task practice in patients with moderate-severe hand impairment by allowing completion of grasp and release tasks that are impossible to complete unassisted.

Robotic Home-Based Rehabilitation Systems Design: From a Literature Review to a Conceptual Framework for Community-Based Remote Therapy During COVID-19 Pandemic

During the COVID-19 pandemic, the higher susceptibility of post-stroke patients to infection calls for extra safety precautions. Despite the imposed restrictions, early neurorehabilitation cannot be postponed due to its paramount importance for improving motor and functional recovery chances. Utilizing accessible state-of-the-art technologies, home-based rehabilitation devices are proposed as a sustainable solution in the current crisis. In this paper, a comprehensive review on developed home-based rehabilitation technologies of the last 10 years (2011-2020), categorizing them into upper and lower limb devices and considering both commercialized and state-of-the-art realms. Mechatronic, control, and software aspects of the system are discussed to provide a classified roadmap for home-based systems development. Subsequently, a conceptual framework on the development of smart and intelligent community-based home rehabilitation systems based on novel mechatronic technologies is proposed. In this framework, each rehabilitation device acts as an agent in the network, using the internet of things (IoT) technologies, which facilitates learning from the recorded data of the other agents, as well as the tele-supervision of the treatment by an expert. The presented design paradigm based on the above-mentioned leading technologies could lead to the development of promising home rehabilitation systems, which encourage stroke survivors to engage in under-supervised or unsupervised therapeutic activities.

Development of Self-Adaptable Mechanism to Compensate Angle-Dependent Flexor Tone of the Elbow Joint Post-stroke: A Pilot Study

Upper extremity impairments are common among stroke survivors. Robotic devices enable a high-dose of repetitive training for patients, but most systems are confined to the laboratory settings due to their complexity and power requirements. Previously we developed a passive elbow device that can counteract the angle-dependent tone of flexor muscles with hypertonia, but its efficacy was found limited as the increase in passive assistance during elbow extension was found not sufficient to provide assistance to those with more severe impairments. Therefore, in this study, we developed a 'self-adaptable' passive device that adjusts its assistance level based on the movements of patients. In addition to the morphological design to adjust moment arms of the elastic components, we incorporated a self-adaptation mechanism, in which the lengths of the elastic bands were adjusted by a pair of miniature linear motors based on the joint position feedback signals. The capacity of the device was then tested in a pilot testing with two healthy subjects, for whom angle-dependent flexion torque was implemented to simulate flexor hypertonia. The additional adjustment of passive component lengths was found to further increase the elbow extension assistance as the elbow joint extended. The proposed self-adapting mechanism, which does not require any complex control input from the experimenters, can be incorporated with the existing passive device to improve its functional efficacy in home-based training.

Passive Elbow Movement Assistant (PEMA): A portable exoskeleton to compensate angle-dependent tone profile of the elbow joint post-stroke

Significant impairments in upper extremity function are commonly observed after neurological injuries such as stroke. While the efficacy of robotic training has been demonstrated, the use of these devices is confined to the laboratory setting due to its complexity and power requirements. In this study, we developed a passive, portable device (Portable Elbow Movement Assistant; PEMA) that can provide assistance during elbow movements of stroke survivors. The geometric properties of the device were designed to allow morphological changes in the elastic components during movements, so that the assistance produced by the elastic component counteract the angle-dependent flexor hypertonia commonly observed in stroke survivors. A mathematical model for the proposed design was first developed to characterize the assistance provided by the device. The capacity of the device was then tested in a pilot testing with four healthy subjects, for whom a custom device to simulate elbow flexor hypertonia (providing an increased resistance for the extended posture) was implemented. The proposed device was found to effectively counteract the angle-dependent flexion moment, produced by the hypertonia simulator, as a significant decrease was observed in the slope of the angle-activation relationship (movement phase) and activation level (hold phase) of the triceps brachii muscle. The assistance did not affect the activation of the antagonist muscle (biceps brachii), indicating an independent modulation of the agonist and antagonist muscles resulted from the assistance.

Inertial Measurement Unit Based Upper Extremity Motion Characterization for Action Research Arm Test and Activities of Daily Living

In practical rehabilitation robot development, it is imperative to pre-specify the critical workspace to prevent redundant structure. This study aimed to characterize the upper extremity motion during essential activities in daily living. An IMU-based wearable motion capture system was used to access arm movements. Ten healthy subjects performed the Action Research Arm Test (ARAT) and six pre-selected essential daily activities. The Euler angles of the major joints, and acceleration from wrist and hand sensors were acquired and analyzed. The size of the workspace for the ARAT was 0.53 (left-right) × 0.92 (front-back) × 0.89 (up-down) m for the dominant hand. For the daily activities, the workspace size was 0.71 × 0.70 × 0.86 m for the dominant hand, significantly larger than the non-dominant hand (p ≤ 0.011). The average range of motion (RoM) during ARAT was 109.15 ± 18.82° for elbow flexion/extension, 105.23 ± 5.38° for forearm supination/pronation, 91.99 ± 0.98° for shoulder internal/external rotation, and 82.90 ± 22.52° for wrist dorsiflexion/volarflexion, whereas the corresponding range for daily activities were 120.61 ± 23.64°, 128.09 ± 22.04°, 111.56 ± 31.88°, and 113.70 ± 18.26°. The shoulder joint was more abducted and extended during pinching compared to grasping posture (p < 0.001). Reaching from a grasping posture required approximately 70° elbow extension and 36° forearm supination from the initial position. The study results provide an important database for the workspace and RoM for essential arm movements.

Usability Study of Mainstream Wearable Fitness Devices: Feature Analysis and System Usability Scale Evaluation

Background

Wearable devices have the potential to promote a healthy lifestyle because of their real-time data monitoring capabilities. However, device usability is a critical factor that determines whether they will be adopted on a large scale. Usability studies on wearable devices are still scarce.

Objective

This study aims to compare the functions and attributes of seven mainstream wearable devices and to evaluate their usability.

Methods

The wearable devices selected were the Apple Watch, Samsung Gear S, Fitbit Surge, Jawbone Up3, Mi Band, Huawei Honor B2, and Misfit Shine. A mixed method of feature comparison and a System Usability Scale (SUS) evaluation based on 388 participants was applied; the higher the SUS score, the better the usability of the product.

Results

For features, all devices had step counting, an activity timer, and distance recording functions. The Samsung Gear S had a unique sports track recording feature and the Huawei Honor B2 had a unique wireless earphone. The Apple Watch, Samsung Gear S, Jawbone Up3, and Fitbit Surge could measure heart rate. All the devices were able to monitor sleep, except the Apple Watch. For product characteristics, including attributes such as weight, battery life, price, and 22 functions such as step counting, activity time, activity type identification, sleep monitoring, and expandable new features, we found a very weak negative correlation between the SUS scores and price (r=−.10, P=.03) and devices that support expandable new features (r=−.11, P=.02), and a very weak positive correlation between the SUS scores and devices that support the activity type identification function (r=.11, P=.02). The Huawei Honor B2 received the highest score of mean 67.6 (SD 16.1); the lowest Apple Watch score was only 61.4 (SD 14.7). No significant difference was observed among brands. The SUS score had a moderate positive correlation with the user’s experience (length of time the device was used) (r=.32, P<.001); participants in the medical and health care industries gave a significantly higher score (mean 61.1, SD 17.9 vs mean 68.7, SD 14.5, P=.03).

Conclusions

The functions of wearable devices tend to be homogeneous and usability is similar across various brands. Overall, Mi Band had the lowest price and the lightest weight. Misfit Shine had the longest battery life and most functions, and participants in the medical and health care industries had the best evaluation of wearable devices. The perceived usability of mainstream wearable devices is unsatisfactory and customer loyalty is not high. A consumer’s SUS rating for a wearable device is related to their personal situation instead of the device brand. Device manufacturers should put more effort into developing innovative functions and improving the usability of their products by integrating more cognitive behavior change techniques.