Adaptive Trajectory Tracking Control of a Parallel Ankle Rehabilitation Robot With Joint-Space Force Distribution

This paper proposes an adaptive trajectory tracking control strategy implemented on a parallel ankle rehabilitation robot with joint-space force distribution. This device is redundantly actuated by four pneumatic muscles (PMs) with three rotational degrees of freedom. Accurate trajectory tracking is achieved through a cascade controller with the position feedback in task space and force feedback in joint space, which enhances training safety by controlling each PM to be in tension in an appropriate level. At a high level, an adaptive algorithm is proposed to enable movement intention-directed trajectory adaptation. This can further help to improve training safety and encourage human-robot engagement. The pilot tests were conducted with an injured human ankle. The statistical data show that normalized root mean square deviation (NRMSD) values of trajectory tracking are all less than 2.3% and the PM force tracking being always controlled in tension, demonstrating its potential in assisting ankle therapy

How a Diverse Research Ecosystem Has Generated New Rehabilitation Technologies: Review of NIDILRR’s Rehabilitation Engineering Research Centers

Over 50 million United States citizens (1 in 6 people in the US) have a developmental, acquired, or degenerative disability. The average US citizen can expect to live 20% of his or her life with a disability. Rehabilitation technologies play a major role in improving the quality of life for people with a disability, yet widespread and highly challenging needs remain. Within the US, a major effort aimed at the creation and evaluation of rehabilitation technology has been the Rehabilitation Engineering Research Centers (RERCs) sponsored by the National Institute on Disability, Independent Living, and Rehabilitation Research. As envisioned at their conception by a panel of the National Academy of Science in 1970, these centers were intended to take a “total approach to rehabilitation”, combining medicine, engineering, and related science, to improve the quality of life of individuals with a disability. Here, we review the scope, achievements, and ongoing projects of an unbiased sample of 19 currently active or recently terminated RERCs. Specifically, for each center, we briefly explain the needs it targets, summarize key historical advances, identify emerging innovations, and consider future directions. Our assessment from this review is that the RERC program indeed involves a multidisciplinary approach, with 36 professional fields involved, although 70% of research and development staff are in engineering fields, 23% in clinical fields, and only 7% in basic science fields; significantly, 11% of the professional staff have a disability related to their research. We observe that the RERC program has substantially diversified the scope of its work since the 1970’s, addressing more types of disabilities using more technologies, and, in particular, often now focusing on information technologies. RERC work also now often views users as integrated into an interdependent society through technologies that both people with and without disabilities co-use (such as the internet, wireless communication, and architecture). In addition, RERC research has evolved to view users as able at improving outcomes through learning, exercise, and plasticity (rather than being static), which can be optimally timed. We provide examples of rehabilitation technology innovation produced by the RERCs that illustrate this increasingly diversifying scope and evolving perspective. We conclude by discussing growth opportunities and possible future directions of the RERC program

Safe Haptics-enabled Patient-Robot Interaction for Robotic and Telerobotic Rehabilitation of Neuromuscular Disorders: Control Design and Analysis

Motivation: Current statistics show that the population of seniors and the incidence rate of age-related neuromuscular disorders are rapidly increasing worldwide. Improving medical care is likely to increase the survival rate but will result in even more patients in need of Assistive, Rehabilitation and Assessment (ARA) services for extended periods which will place a significant burden on the world\u27s healthcare systems. In many cases, the only alternative is limited and often delayed outpatient therapy. The situation will be worse for patients in remote areas. One potential solution is to develop technologies that provide efficient and safe means of in-hospital and in-home kinesthetic rehabilitation. In this regard, Haptics-enabled Interactive Robotic Neurorehabilitation (HIRN) systems have been developed. Existing Challenges: Although there are specific advantages with the use of HIRN technologies, there still exist several technical and control challenges, e.g., (a) absence of direct interactive physical interaction between therapists and patients; (b) questionable adaptability and flexibility considering the sensorimotor needs of patients; (c) limited accessibility in remote areas; and (d) guaranteeing patient-robot interaction safety while maximizing system transparency, especially when high control effort is needed for severely disabled patients, when the robot is to be used in a patient\u27s home or when the patient experiences involuntary movements. These challenges have provided the motivation for this research. Research Statement: In this project, a novel haptics-enabled telerobotic rehabilitation framework is designed, analyzed and implemented that can be used as a new paradigm for delivering motor therapy which gives therapists direct kinesthetic supervision over the robotic rehabilitation procedure. The system also allows for kinesthetic remote and ultimately in-home rehabilitation. To guarantee interaction safety while maximizing the performance of the system, a new framework for designing stabilizing controllers is developed initially based on small-gain theory and then completed using strong passivity theory. The proposed control framework takes into account knowledge about the variable biomechanical capabilities of the patient\u27s limb(s) in absorbing interaction forces and mechanical energy. The technique is generalized for use for classical rehabilitation robotic systems to realize patient-robot interaction safety while enhancing performance. In the next step, the proposed telerobotic system is studied as a modality of training for classical HIRN systems. The goal is to first model and then regenerate the prescribed kinesthetic supervision of an expert therapist. To broaden the population of patients who can use the technology and HIRN systems, a new control strategy is designed for patients experiencing involuntary movements. As the last step, the outcomes of the proposed theoretical and technological developments are translated to designing assistive mechatronic tools for patients with force and motion control deficits. This study shows that proper augmentation of haptic inputs can not only enhance the transparency and safety of robotic and telerobotic rehabilitation systems, but it can also assist patients with force and motion control deficiencies

Stretching adversely modulates locomotor capacity following spinal cord injury via activation of nociceptive afferents.

Spinal cord injury (SCI) is the second leading cause of paralysis in the United States, affecting around 282,000 people with 17,000 new cases each year. Initial and secondary damage to the spinal cord disrupts multiple descending pathways that modulate the function of sympathetic preganglionic neurons and central pattern generating circuitry. Resulting loss of autonomic and locomotor functions, as well as decreased levels of physical activity, lead to a myriad of complications that affect multiple organ systems and significantly reduce both quality of life and life expectancy in individuals with SCI. Spasticity and muscle contractures are two common secondary conditions that develop in the chronic stages of SCI as a result of neurobiological and soft tissue adaptations. Stretching is the widely accepted initial therapy for the treatment of both spasticity and muscle contractures. Unlike humans, rats with experimental incomplete SCI have robust locomotor recovery and do not develop significant muscle contractures or spasticity. One of the long-standing operating principles in the Magnuson laboratory is that rats retrain or rehabilitate themselves through large amounts of in-cage activity. A previous graduate student in our lab, Krista Caudle, tested this hypothesis using custom designed wheelchairs to immobilize Sprague Dawley rats with mild-moderate SCIs. As expected, the immobilized SCI animals did not recover their locomotor function and, in addition, developed muscle contractures. To mimic the approach used in the clinic for the treatment of contractures, a hindlimb stretching protocol was developed and implemented as part of our daily care routine. As a control, non-immobilized SCI rats also received stretching therapy. Surprisingly, stretched rats and wheelchair immobilized rats showed similar impairments in locomotor recovery. This finding was alarming and warranted further studies. The work presented in this thesis is a continuation of the stretching projects in the Magnuson laboratory. Four major studies were carried out in order to improve our understanding of this stretching phenomenon and to begin uncovering the underlying physiological mechanisms. The following experiments revealed that hindlimb stretching disrupts locomotor function in rats with acute and chronic moderately-severe SCI. We also determined that dynamic “range of motion” stretching resulted in a similar pattern of locomotor impairment as our standard static stretch-and-hold protocol in rats with moderate sub-acute SCIs. Furthermore, using kinematics and electromyography (EMG), we determined that one of the most frequent responses to stretch in the rat hindlimbs is similar to human clonus. The significance of these findings are three-fold. First, to our knowledge, there has not been a specific description of clonus in the rat model of the SCI previously. Second, the similarity of the responses to stretch between rats and humans make a compelling argument for the clinical relevance of the stretching phenomenon. Finally, we determined that stretch-induced locomotor deficits depend on the presence of nociceptive afferents. Speculations about the specific physiological mechanisms of the stretching phenomenon and future directions are discussed. Comprehensive review of the stretching literature revealed a major problem in the rationale that is frequently provided for the use of stretching in the management of muscle contractures after SCI. In light of this work, a perspective on the future of stretching therapy in the rehabilitation after SCI is provided

Design of a wearable active ankle-foot orthosis for both sides

Dissertação de mestrado integrado em Engenharia Biomédica (área de especialização em Biomateriais, Reabilitação e Biomecânica)Portugal is the west European country with the highest rate of stroke-related mortality, being that, of those who suffer cerebrovascular accidents, 40% feature an impairment which can manifest itself through motor sequelae, namely drop foot. An ankle-foot orthosis is often recommended to passively accommodate these motor problems; however, active/powered exoskeletons are also a suitable solution for post-stroke patients. Due to the high complexity of the human ankle joint, one of the problems regarding these active devices is the misalignment occurring between the rehabilitation device and the human joint, which is a cause of parasitic forces, discomfort, and pain. The present master dissertation proposes the development of an adjustable wearable active ankle-foot orthosis that is able to tackle this misalignment issue concerning commercially available lower limb orthotic devices. This work is integrated on the SmartOs – Smart, Stand-alone Active Orthotic System – project that proposes an innovative robotic technology (a wearable mobile lab) oriented to gait rehabilitation. The conceptual design of a standard version of the SmartOs wearable active orthosis was initiated with the analysis of another ankle-foot orthosis – Exo-H2 (Technaid) – from which the necessary design changes were implemented, aiming at the improvement of the established device. In order to achieve a conceptual solution, both the practical knowledge of the Orthos XXI design team and several design methods were used to ensure the accomplishment of the defined requirements. The detailed design process of the standard SmartOs wearable active orthosis prototype is disclosed. With the purpose of validating the design, the critical components were simulated with the resources available in SolidWorks®, and the necessary CAD model’s adaptations were implemented to guarantee a reliable and safe design. The presented design is currently set for further production in Orthos XXI, followed by the mandatory mechanical tests.Portugal é o país da Europa ocidental com maior taxa de mortalidade por acidente vascular cerebral (AVC), sendo que, dos que sofrem acidentes vasculares cerebrais, 40% apresentam uma deficiência que pode manifestar-se por sequelas motoras, nomeadamente o pé pendente. Uma ortótese do tornozelo é recomendada frequentemente para acomodar passivamente esses problemas motores; no entanto, exoesqueletos ativos são também uma solução adequada para pacientes pós-AVC. Devido à alta complexidade da articulação do tornozelo humano, um dos problemas associados a esses dispositivos ativos é o desalinhamento que ocorre entre o dispositivo de reabilitação e a articulação humana, que é uma causa de forças parasitas, desconforto e dor. A presente dissertação de mestrado propõe o desenvolvimento de uma ortótese ativa do tornozelo ajustável e vestível, que seja capaz de resolver esse problema de desalinhamento relativo aos dispositivos ortóticos de membros inferiores disponíveis comercialmente. Este trabalho está integrado no projeto SmartOs - Smart, Stand-alone Active Orthotic System - projeto que propõe uma tecnologia robótica inovadora (wearable mobile lab) direcionada para a reabilitação da marcha. O projeto conceptual de uma versão padrão da ortótese ativa vestível do projeto SmartOs foi iniciado com a análise de outra ortótese do tornozelo – Exo-H2 (Technaid) - a partir da qual foram implementadas as alterações de projeto necessárias, visando o aprimoramento do dispositivo estabelecido. Para se chegar a uma solução conceptual, tanto o conhecimento prático da equipa de projeto da Orthos XXI como os diversos métodos de projeto foram utilizados para garantir o cumprimento dos requisitos definidos. O processo do desenho detalhado da versão padrão da ortótese ativa SmartOs será também divulgado. Com o objetivo de validar o projeto, os componentes críticos foram simulados com os recursos disponíveis no SolidWorks® e as adaptações necessárias do modelo CAD foram implementadas para garantir um projeto fidedigno e seguro. O projeto apresentado está atualmente em preparação para produção na empresa Orthos XXI, depois do qual se seguem os ensaios mecânicos obrigatórios

Psychological and care impact of the daily use of a pediatric gait exoskeleton in children with spinal muscular atrophy

Introducción: La Atrofia Muscular Espinal Tipo II, es una enfermedad neurodegenerativa de origen genético que cursa con debilidad muscular y provoca deterioro motor e incapacidad para caminar en los niños. Se relaciona con graves problemas respiratorios, musculoesqueléticos, gastrointestinales y otros de salud y cuidado. Los exoesqueletos robóticos de miembros inferiores son dispositivos médicos que ayudan a la marcha de pacientes que no pueden caminar. Nuestro objetivo fue evaluar el impacto en la dimensión psicológica y de autocuidado derivado del uso del exoesqueleto ATLAS en el hogar en niños con Atrofia Muscular Espinal Tipo II. Metodología: tres niños con Atrofia Muscular Espinal Tipo II utilizaron el exoesqueleto en casa cinco días a la semana durante un período de dos meses para caminar y realizar actividades. Se realizó una evaluación del autocuidado de enfermería antes y durante el uso del dispositivo para evaluar los cambios en los resultados del autocuidado y los diagnósticos de enfermería. Se realizaron entrevistas en profundidad y semiestructuradas, además de la observación durante las sesiones, para evaluar el impacto de la experiencia en la dimensión psicológica de los participantes. Resultados: el uso del exoesqueleto produjo cambios en los condicionantes básicos de los niños y una mejora en los organismos de autocuidado. También aparecieron nuevas demandas de autocuidado. Tres de los diez diagnósticos de enfermería fueron resueltos. Asimismo, los niños mostraron una buena tolerancia a la actividad además de una mejora funcional evaluada en el tercer participante. Los niños y los cuidadores principales valoraron la experiencia como positiva y significativa. Los niños tenían una mayoría de emociones positivas, y se incrementó su autonomía y comportamiento social y exploratorio. Conclusiones: la tecnología del exoesqueleto podría considerarse como un nuevo recurso para el cuidado de niños con enfermedades neuromusculares. Su uso tuvo un impacto positivo tanto en las variables de autocuidado como en la dimensión psicológica de tres niños con atrofia muscular espinal tipo II. Aunque este estudio aporta ya evidencia, más estudios sobre el tema aportarían un mayor conocimiento

Robot-assisted training compared with an enhanced upper limb therapy programme and with usual care for upper limb functional limitation after stroke: the RATULS three-group RCT

Background Loss of arm function is common after stroke. Robot-assisted training may improve arm outcomes. Objective The objectives were to determine the clinical effectiveness and cost-effectiveness of robot-assisted training, compared with an enhanced upper limb therapy programme and with usual care. Design This was a pragmatic, observer-blind, multicentre randomised controlled trial with embedded health economic and process evaluations. Setting The trial was set in four NHS trial centres. Participants Patients with moderate or severe upper limb functional limitation, between 1 week and 5 years following first stroke, were recruited. Interventions Robot-assisted training using the Massachusetts Institute of Technology-Manus robotic gym system (InMotion commercial version, Interactive Motion Technologies, Inc., Watertown, MA, USA), an enhanced upper limb therapy programme comprising repetitive functional task practice, and usual care. Main outcome measures The primary outcome was upper limb functional recovery ‘success’ (assessed using the Action Research Arm Test) at 3 months. Secondary outcomes at 3 and 6 months were the Action Research Arm Test results, upper limb impairment (measured using the Fugl-Meyer Assessment), activities of daily living (measured using the Barthel Activities of Daily Living Index), quality of life (measured using the Stroke Impact Scale), resource use costs and quality-adjusted life-years. Results A total of 770 participants were randomised (robot-assisted training, n = 257; enhanced upper limb therapy, n = 259; usual care, n = 254). Upper limb functional recovery ‘success’ was achieved in the robot-assisted training [103/232 (44%)], enhanced upper limb therapy [118/234 (50%)] and usual care groups [85/203 (42%)]. These differences were not statistically significant; the adjusted odds ratios were as follows: robot-assisted training versus usual care, 1.2 (98.33% confidence interval 0.7 to 2.0); enhanced upper limb therapy versus usual care, 1.5 (98.33% confidence interval 0.9 to 2.5); and robot-assisted training versus enhanced upper limb therapy, 0.8 (98.33% confidence interval 0.5 to 1.3). The robot-assisted training group had less upper limb impairment (as measured by the Fugl-Meyer Assessment motor subscale) than the usual care group at 3 and 6 months. The enhanced upper limb therapy group had less upper limb impairment (as measured by the Fugl-Meyer Assessment motor subscale), better mobility (as measured by the Stroke Impact Scale mobility domain) and better performance in activities of daily living (as measured by the Stroke Impact Scale activities of daily living domain) than the usual care group, at 3 months. The robot-assisted training group performed less well in activities of daily living (as measured by the Stroke Impact Scale activities of daily living domain) than the enhanced upper limb therapy group at 3 months. No other differences were clinically important and statistically significant. Participants found the robot-assisted training and the enhanced upper limb therapy group programmes acceptable. Neither intervention, as provided in this trial, was cost-effective at current National Institute for Health and Care Excellence willingness-to-pay thresholds for a quality-adjusted life-year. Conclusions Robot-assisted training did not improve upper limb function compared with usual care. Although robot-assisted training improved upper limb impairment, this did not translate into improvements in other outcomes. Enhanced upper limb therapy resulted in potentially important improvements on upper limb impairment, in performance of activities of daily living, and in mobility. Neither intervention was cost-effective. Future work Further research is needed to find ways to translate the improvements in upper limb impairment seen with robot-assisted training into improvements in upper limb function and activities of daily living. Innovations to make rehabilitation programmes more cost-effective are required. Limitations Pragmatic inclusion criteria led to the recruitment of some participants with little prospect of recovery. The attrition rate was higher in the usual care group than in the robot-assisted training or enhanced upper limb therapy groups, and differential attrition is a potential source of bias. Obtaining accurate information about the usual care that participants were receiving was a challenge. Trial registration Current Controlled Trials ISRCTN69371850. Funding This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 54. See the NIHR Journals Library website for further project information

Clinical Pathways in Stroke Rehabilitation

This open access book focuses on practical clinical problems that are frequently encountered in stroke rehabilitation. Consequences of diseases, e.g. impairments and activity limitations, are addressed in rehabilitation with the overall goal to reduce disability and promote participation. Based on the available best external evidence, clinical pathways are described for stroke rehabilitation bridging the gap between clinical evidence and clinical decision-making. The clinical pathways answer the questions which rehabilitation treatment options are beneficial to overcome specific impairment constellations and activity limitations and are well acceptable to stroke survivors, as well as when and in which settings to provide rehabilitation over the course of recovery post stroke. Each chapter starts with a description of the clinical problem encountered. This is followed by a systematic, but concise review of the evidence (RCTs, systematic reviews and meta-analyses) that is relevant for clinical decision-making, and comments on assessment, therapy (training, technology, medication), and the use of technical aids as appropriate. Based on these summaries, clinical algorithms / pathways are provided and the main clinical-decision situations are portrayed. The book is invaluable for all neurorehabilitation team members, clinicians, nurses, and therapists in neurology, physical medicine and rehabilitation, and related fields. It is a World Federation for NeuroRehabilitation (WFNR) educational initiative, bridging the gap between the rapidly expanding clinical research in stroke rehabilitation and clinical practice across societies and continents. It can be used for both clinical decision-making for individuals and as well as clinical background knowledge for stroke rehabilitation service development initiatives. ; Provides evidence-based clinical practice guidelines for stroke rehabilitation Discusses clinical problems and evidence, comments on assessment, therapy and technical aids Written by experienced experts with a background in clinical practic