Pilot Test of Dosage Effects in HEXORR II for Robotic Hand Movement Therapy in Individuals With Chronic Stroke

Impaired use of the hand in functional tasks remains difficult to overcome in many individuals after a stroke. This often leads to compensation strategies using the less-affected limb, which allows for independence in some aspects of daily activities. However, recovery of hand function remains an important therapeutic goal of many individuals, and is often resistant to conventional therapies. In prior work, we developed HEXORR I, a robotic device that allows practice of finger and thumb movements with robotic assistance. In this study, we describe modifications to the device, now called HEXORR II, and a clinical trial in individuals with chronic stroke. Fifteen individuals with a diagnosis of chronic stroke were randomized to 12 or 24 sessions of robotic therapy. The sessions involved playing several video games using thumb and finger movement. The robot applied assistance to extension movement that was adapted based on task performance. Clinical and motion capture evaluations were performed before and after training and again at a 6-month followup. Fourteen individuals completed the protocol. Fugl-Meyer scores improved significantly at the 6 month time point compared to baseline, indicating reductions in upper extremity impairment. Flexor hypertonia (Modified Ashworth Scale) also decreased significantly due to the intervention. Motion capture found increased finger range of motion and extension ability after the intervention that continued to improve during the followup period. However, there was no change in a functional measure (Action Research Arm Test). At the followup, the high dose group had significant gains in hand displacement during a forward reach task. There were no other significant differences between groups. Future work with HEXORR II should focus on integrating it with functional task practice and incorporating grip and squeezing tasks.Trial Registration:ClinicalTrials.gov, NCT04536987. Registered 3 September 2020 - Retrospectively registered, https://clinicaltrials.gov/ct2/show/record/NCT04536987

Robotics in health care: Perspectives of robot-aided interventions in clinical practice for rehabilitation of upper limbs

This article belongs to the Special Issue Rehabilitation Robotics: Recent Advancements and New Perspectives about Training and Assessment of Sensorimotor Functions.Robot-aided systems to support the physical rehabilitation of individuals with neurological impairment is one of the fields that has been widely developed in the last few decades. However, the adoption of these systems in clinical practice remains limited. In order to better understanding the causes of this limitation, a systematic review of robot-based systems focused on upper extremity rehabilitation is presented in this paper. A systematic search and review of related articles in the literature were conducted. The chosen works were analyzed according to the type of device, the data analysis capability, the therapy method, the human–robot interaction, the safety strategies, and the focus of treatment. As a conclusion, self-adaptation for personalizing the treatments, safeguarding and enhancing of patient–robot interaction towards training essential factors of movement generation into the same paradigm, or the use of lifelike environments in fully-immersive virtual reality for increasing the assimilation of motor gains could be relevant factors to develop more accepted robot-aided systems in clinical practice.This work was supported in part by the Spanish Ministry of Economy and Competitiveness via the ROBOESPASproject (DPI2017-87562-C2-1-R) and in part by the RoboCity2030-DIH-CMMadrid Robotics Digital Innovation Hub ("Robótica aplicada a la mejora de la calidad de vida de los ciudadanos, Fase IV"; S2018/NMT-4331), which is funded by the Programas de Actividades I+DComunidad de Madrid and cofunded by the Structural Funds of the EU

Advancing the Functionality and Wearability of Robotic Hand Orthoses Towards Activities of Daily Living in Stroke Patients

Post stroke rehabilitation is effective when a large number of motor repetitions are provided to patients. However, conventional physical therapy or traditional desktop-size robot aided rehabilitation do not provide sufficient number of repetitions due to cost and logistical barriers. Our vision is to realize a wearable and functional hand orthosis that could be used outside of controlled, clinical settings, thus allowing for more training repetitions. Furthermore, if such a device can prove effective for Activities of Daily Living (ADLs) while actively worn, this can incentivize patients to increase its use, further enhancing rehabilitative effects. However, in order to provide such clinical benefits, the device must be completely wearable without obtrusive features, and intuitive to control even for non-experts. In this thesis, we thus focus on wearability, functionality, and intuitive intent detection technology for a novel hand robot, and assess its performance when used both as a rehabilitative device and an assistive tool. A fully wearable device must deliver meaningful manipulation capability in small and lightweight package. In this context, we investigate the capability of single-actuator devices to assist whole hand movement patterns through a network of exotendons. Our prototypes combine a single linear actuator (mounted on a forearm splint) with a network of exotendons (routed on the surface of a soft glove). We investigate two possible tendon network configurations: one that produces full finger extension (overcoming flexor spasticity) and one that combines proximal flexion with distal extension at each finger. In experiments with stroke survivors, we measure the force levels needed to overcome various levels of spasticity and to open the hand for grasping using the first of these configurations, and qualitatively demonstrate the ability to execute fingertip grasps using the second. Our results support the feasibility of developing future wearable devices able to assist a range of manipulation tasks. In order to further improve the wearability of the device, we propose two designs that provide effective force transmission by increasing moment arms around finger joints. We evaluate the designs with geometric models and experiment using a 3D-printed artificial finger to find force and joint angle characteristics of the suggested structures. We also perform clinical tests with stroke patients to demonstrate the feasibility of the designs. The testing supports the hypothesis that the proposed designs efficiently elicit extension of the digits in patients with spasticity as compared to existing baselines. With the suggested transmission designs, the device can deliver sufficient extension force even when the users have increased muscle tone due to fatigue. The vision of an orthotic device used for ADLs can only be realized if the patients are able to operate the device themselves. However, the field is generally lacking effective methods by which the user can operate the device: such controls must be effective, intuitive, and robust to the wide range of possible impairment patterns. The variety of encountered upper limb impairment patterns in stroke patients means that a single sensing modality, such as electromyography, might not be sufficient to enable controls for a broad range of users. To address this significant gap, we introduce a multimodal sensing and interaction paradigm for an active hand orthosis. In our proof-of-concept implementation, EMG is complemented by other sensing modalities, such as finger bend and contact pressure sensors. We propose multimodal interaction methods that utilize this sensory data as input, and show they can enable tasks for stroke survivors who exhibit different impairment patterns. We then assess the performance of the robotic orthosis for two possible roles: as a therapeutic tool that facilitates device mediated hand exercises to recover neuromuscular function, or as an assistive device for use in everyday activities to aid functional use of the hand. 11 chronic stroke (> 2 years) patients with moderate muscle tone (Modified Ashworth Scale ≤ 2 in upper extremity) engage in a month-long training protocol using the orthosis. Individuals are evaluated using standardized outcome measures, both with and without orthosis assistance. The results highlight the potential for wearable and user-driven robotic hand orthoses to extend the use and training of the affected upper limb after stroke. The advances proposed in this thesis have the potential to enable robotic based hand rehabilitation during daily activities (as opposed to isolated hand exercises with limited upper limb engagement) and over extended periods of time, even in a patient’s home environment. Numerous challenges must still be overcome in order to achieve this vision, related to design (compact devices with easier donning/doffing), control (robust yet intuitive intent inferral), and effectiveness (improved functionality in a wider range of metrics). However, if these challenges can be addressed, wearable robotic devices have the potential to greatly extend the use and training of the affected upper limb after stroke, and help improve the quality of life for a large patient population

WiGlove : A Passive Dynamic Orthosis for Home-based Post-stroke Rehabilitation of Hand and Wrist

Stroke survivors often experience varying levels of motor function deficits in their hands affecting their ability to perform activities of daily life. Recovering their hand functions through neurorehabilitation is a significant step in their recovery towards independent living. Home-based rehabilitation using robotic devices allows stroke survivors to train at their convenience independent of factors such as the availability of therapists’ appointments and the need for frequent travel to outpatient clinics. While many robotic solutions have been proposed to address the above concerns, most focus on training only the wrist or the fingers, neglecting the synergy between the two. To address this, the WiGlove was co-designed to allow hemiparetic stroke survivors to train both the wrist and fingers in the comfort of their homes. The central hypothesis of this work is to investigate if a device designed using user-centred methods featuring aspects of usability such as easy donning and doffing and wireless operation, can act as a feasible tool for home-based rehabilitation of the hand and wrist following stroke. In order to aid this investigation, we tackled this task in three stages of usability and feasibility evaluations. Firstly, healthy participants tried the current state of the art, the SCRIPT Passive Orthosis, as well as the WiGlove, in a counterbalanced, within-subject experiment and attested to WiGlove’s improvement in several aspects of usability such as ease of don/doffing, suitability for ADL, unblocked natural degrees of freedom, safety and aesthetic appeal. Subsequently, a heuristic evaluation with six stroke therapists validated these improvements and helped identify issues they perceived to potentially affect the device’s acceptance. Integrating this feedback, the updated WiGlove was subjected to a six-week summative feasibility evaluation with two stroke survivors, with varying levels of impairment, in their homes without supervision from the therapists. Results from this study were overwhelmingly positive on the usability and acceptance of the WiGlove. Furthermore, in the case of the first participant who trained with it for a total of 39 hours, notable improvements were observed in the participant’s hand functions. It showed that even without a prescribed training protocol, both participants were willing to train regularly with the WiGlove and its games, sometimes several times a day. These results demonstrate that WiGlove can be a promising tool for home-based rehabilitation for stroke survivors and serve as evidence for a larger user study with more participants with varying levels of motor impairments due to stroke. The findings of this study also offer preliminary evidence supporting the effectiveness of training with the WiGlove, particularly in the case of the first participant, who exhibited a significant reduction of tone in the hand as a result of increased training intensity. Owing to the participant’s satisfaction with the device, it was requested by him to extend his involvement in the study by using the WiGlove for a longer duration which was facilitated

Development of a home-based Computer Assisted Arm Rehabilitation (hCAAR) device for upper limb exercises in stroke patients

Home-based robotic technologies may offer the possibility of self-directed upper limb exercise after stroke as a means of increasing the intensity of rehabilitation treatment. The aim of this research project was to develop and evaluate a robotic device hCAAR that can be used independently at home by stroke survivors with upper limb weakness. The project had two stages: Stage 1, hCAAR development using a user-centred design process; Stage 2, A feasibility clinical study in the home setting. Stage 1: Nine stroke survivors with upper limb weakness and six healthcare professionals were involved in the concept and design stages of device development. hCAAR consists of a powered joystick with a computer interface, which is used to direct the movement of the upper limb to perform therapeutic movements as directed by tasks on the screen. hCAAR also provides controlled assistance when the user’s voluntary upper limb movement is insufficient to complete the prescribed task. Stage 2: In the feasibility study, 19 participants (stroke survivors with upper limb weakness) were recruited and 17 participants used hCAAR in their homes for eight weeks. No serious adverse events were reported. All 17 participants were able to use the device independently. A statistically significant improvement was observed in the kinematic and clinical outcomes. Three participants showed clinically significant improvement in all clinical outcomes. Five participants reported improvement in functional ability in daily activities. Participants, family members and therapists were satisfied with the usability of hCAAR in the home setting. This research project also demonstrated that the International Classification of Functioning, Disability and Health (ICF) Comprehensive Core Set for stroke provides a useful basis to structure interviews to gather feedback from end-users and healthcare professionals in different stages of the rehabilitation device development. In summary, hCAAR is a home-based rehabilitation robotic device that can be independently used by stroke survivors with upper limb weakness and has the potential to improve upper limb movement and function

Diseño y control de exoesqueleto robótico para la rehabilitación y asistencia de los movimientos de la mano

Programa de Doctorado en Tecnologías Industriales y de Telecomunicación por la Universidad Miguel Hernández de ElcheHands are one of the main instruments used by humans for interacting with physical environment. Furthermore, hands play an important role in other aspects of daily living such as non-verbal communication or postural control assisted by external supports. Therefore, individuals that suffer some kind of hand impairment become dependent in many common situations, reducing their quality of life. Developments in the field of robotics result in potential solutions to overcome their dependency. In particular, wearable devices such as exoskeletons can help to lessen the impact of the impairment by becoming a new tool for providing more intense and effective rehabilitation therapies, or by their potential applications to assist people during their activities of daily living in a domestic environment. This Doctoral Thesis focuses on the development of a robotic exoskeleton that, due to its constructive features, can be applied to both rehabilitation and assitance environments. As an innovation, this exoskeleton has a new type of force sensor architecture, integrable in the device, favoring the lightness and portability of the equipment and offering a versatile force control interface in a multitude of environments. Along with the force interface, other types of interfaces based on biological and kinematic parameters are studied, in order to provide the system with the necessary versatility to adapt to different user profiles. In addition, two practical applications of the device are presented in complex rehabilitation settings and everyday situations not previously studied. The results of this work are compiled in four publications in journals indexed in the Journal Citation Reports (JCR). The publication Multimodal robotic system for upper-limb rehabilitation in physical environment studies the integration of the hand exoskeleton in a system of robots and sensors that allow the implementation of manipulative therapies in real environments, using a human-machine interface based on electromyographic signals. As an alternative to electromyography for advanced stages of rehabilitation, new interfaces based on motion capture and force feedback are proposed, results are published in the paper Hand exoskeleton for rehabilitation therapies with integrated optical force sensor. A detailed description of the force sensor integrated in the exoskeleton can be found in the publication Customizable optical force sensor for fast prototyping and cost-effective applications. Finally, the publication Exploring new potential applications for Hand Exoskeletons: Power grip to assist human standing studies the applicability of hand exoskeletons to improve postural control

Development of a hybrid assist-as-need hand exoskeleton for stroke rehabilitation.

Stroke is one of the leading causes of disability globally and can significantly impair a patient’s ability to function on a daily basis. Through physical rehabilitative measures a patient may regain a level of functional independence. However, required therapy dosages are often not met. Rehabilitation is typically implemented through manual one-to-one assistance with a physiotherapist, which quickly becomes labour intensive and costly. Hybrid application of functional electrical stimulation (FES) and robotic support can access the physiological benefits of direct muscle activation while providing controlled and repeatable motion assistance. Furthermore, patient engagement can be heightened through the integration of a volitional intent measure, such as electromyography (EMG). Current hybrid hand-exoskeletons have demonstrated that a balanced hybrid support profile can alleviate FES intensity and motor torque requirements, whilst improving reference tracking errors. However, these support profiles remain fixed and patient fatigue is not addressed. The aim of this thesis was to develop a proof-of-concept assist-as-need hybrid exoskeleton for post-stroke hand rehabilitation, with fatigue monitoring to guide the balance of support modalities. The device required the development and integration of a constant current (CC) stimulator, stimulus-resistant EMG device, and hand-exoskeleton. The hand exoskeleton in this work was formed from a parametric Watt I linkage model that adapts to different finger sizes. Each linkage was optimised with respect to angular precision and compactness using Differential Evolution (DE). The exoskeleton’s output trajectory was shown to be sensitive to parameter variation, potentially caused by finger measurement error and shifts in coupler placement. However, in a set of cylindrical grasping trials it was observed that a range of movement strategies could be employed towards a successful grasp. As there are many possible trajectories that result in a successful grasp, it was deduced that the exoskeleton can still provide functional assistance despite its sensitivity to parameter variation. The CC stimulator developed in this work has a part cost of USD $145 and allows flexible adjustment of waveform parameters through an on-board micro-controller. The device is designed to output current up to ±30mA given a voltage compliance of ±50V. When applied across a 2kΩ load, the device exhibited a linear output transfer function, with a maximum ramp tracking error of 5 The stimulus-resistant EMG device builds on current designs by using a novel Schmitt trigger based artefact detection channel to adaptively blank stimulation artefacts without stimulator synchronisation. The design has a part cost of USD$150 and has been made open-source. The device demonstrated its ability to record EMG over its predominant energy spectrum during stimulation, through the stimulation electrodes or through separate electrodes. Pearson’s correlation coefficients greater than 0.84 were identified be- tween the normalised spectra of volitional EMG (vEMG) estimates during stimulation and of stimulation-free EMG recordings. This spectral similarity permits future research into applications such as spectral-based monitoring of fatigue and muscle coherence, posing an advantage over current same-electrode stimulation and recording systems, which can- not sample the lower end of the EMG spectrum due to elevated high-pass filter cut-off frequencies. The stimulus-resistant EMG device was used to investigate elicited EMG (eEMG)-based fatigue metrics during vEMG-controlled stimulation and hybrid support profiles. During intermittent vEMG-controlled stimulation, the eEMG peak-to-peak amplitude (PTP) index was the median frequency (MDF) had a negative correlation for all subjects with R > 0:62 during stimulation-induced wrist flexion and R > 0:55 during stimulation-induced finger flexion. During hybrid FES-robotic support trials, a 40% reduction in stimulus intensity resulted in an average 21% reduction in MDF gradient magnitudes. This reflects lower levels of fatigue during the hybrid support profile and indicates that the MDF gradient can provide useful information on the progression of muscle fatigue. A hybrid exoskeleton system was formed through the integration of the CC stimulator, stimulus-resistant EMG device, and the hand exoskeleton developed in this work. The system provided assist-as-need functional grasp assistance through stimulation and robotic components, governed by the user’s vEMG. The hybrid support profile demonstrated consistent motion assistance with lowered stimulation intensities, which in-turn lowered the subjects’ perceived levels of fatigue

Manipulador aéreo con brazos antropomórficos de articulaciones flexibles

[Resumen] Este artículo presenta el primer robot manipulador aéreo con dos brazos antropomórficos diseñado para aplicarse en tareas de inspección y mantenimiento en entornos industriales de difícil acceso para operarios humanos. El robot consiste en una plataforma aérea multirrotor equipada con dos brazos antropomórficos ultraligeros, así como el sistema de control integrado de la plataforma y los brazos. Una de las principales características del manipulador es la flexibilidad mecánica proporcionada en todas las articulaciones, lo que aumenta la seguridad en las interacciones físicas con el entorno y la protección del propio robot. Para ello se ha introducido un compacto y simple mecanismo de transmisión por muelle entre el eje del servo y el enlace de salida. La estructura en aluminio de los brazos ha sido cuidadosamente diseñada de forma que los actuadores estén aislados frente a cargas radiales y axiales que los puedan dañar. El manipulador desarrollado ha sido validado a través de experimentos en base fija y en pruebas de vuelo en exteriores.Ministerio de Economía y Competitividad; DPI2014-5983-C2-1-