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Control interfaces to actively support the arm function of men with Duchenne Muscular Dystrophy

Authors:
  • ABLE Human Motion

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Adults with DMD can benefit from active arm supports that augment their residual functional capabilities. However, intuitively controlled and fully actuated arm supports are currently not commercially available and adults with DMD are limited to use external robotic arms which contribute to the disuse of their arms. To fill this gap in the field of arm supports, we have developed EMG and force-based control interfaces that have been implemented in two new active arm supports: the A-Arm and the Active A-Gear.We found that both EMG and force-based control interfaces are feasible solutions for the control of active arm support for adults with DMD that have lost their arm function a long time ago. The comparative studies between EMG and force-based control interfaces indicated that, in general, EMG-based control interfaces are better suited for adults with DMD than force-based control interfaces as they are experienced as less fatiguing. Nevertheless, force-based control interfaces with active gravity and joint-stiffness compensation can be a better alternative for those cases in which voluntary forces would still be higher than the intrinsic forces of the arms. This conclusion has an indicative value, as it is based on a low number of subjects. In any case, the decision on the most suited interface will have to be taken based on the specificities of each subject. In conclusion, by developing these new control interfaces and implementing them in new active assistive devices, we made a significant step in improving arm supports for adults with DMD. Hopefully, these novel concepts of arm supports will be the basis for the development of commercially available active arm supports for people with severe muscular weakness. The control and assistive strategies developed in the Flextension A-Gear project may be applicable to other patient groups with muscular weakness.
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... While the life expectancy of people with DMD has increased [4], due to dependency on caregivers, their self-reported quality of life remains poor [5]. Patient groups have expressed a clear desire for technical solutions, in order to achieve a greater degree of independence by using their own limbs for as long as possible [6,7]. ...
... Wearable robotic exoskeletons (WREs) can serve as means to achieve this goal. Such devices can assist in activities of daily living (ADLs) and at the same time enable users to use their own limbs [6], as opposed to external robotic grippers controlled remotely by a joystick and passive splints (Figure 1b) that are often used in DMD [6,7]. Strapped around limbs (see Figure 1c), WREs support and augment the impaired motor function of users. ...
... Wearable robotic exoskeletons (WREs) can serve as means to achieve this goal. Such devices can assist in activities of daily living (ADLs) and at the same time enable users to use their own limbs [6], as opposed to external robotic grippers controlled remotely by a joystick and passive splints (Figure 1b) that are often used in DMD [6,7]. Strapped around limbs (see Figure 1c), WREs support and augment the impaired motor function of users. ...
Article
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Recently, several research projects in the Nether-lands have focused on the development of wearable robotic exoskeletons (WREs) for individuals with Duchenne muscular dystrophy (DMD). Such research on WREs is often treated solely within the disciplines of biomedical and mechanical engineering, overlooking insights from disability studies and philosophy of technology. We argue that mainly two such insights should receive attention: the problematization of the ableism connected to the individual model of disability and the stigmatization by assistive technology. While disability studies have largely rejected the individual model of disability, the engineering sciences seem to still locate disability in an individual's body, not questioning their own problematization of disability. Additionally, philosophy of technology has argued that technologies are not neutral instruments but shape users' actions and perceptions. The design of WREs may convey a message about the understanding of disability, which can be comprehended as a challenge and an opportunity: stigmatization needs to be avoided and positive views on disability can be evoked. This article aims to highlight the benefits of considering these socio-philosophical perspectives by examining the case of WREs for people with DMD and proposing design principles for WREs. These principles may enhance acceptability of WREs, not only by individuals with DMD but also by other users, and help engineers to better place their work in the social context.
... The functionality of the legs is effectively supported using wheelchairs. The Flextension A-Gear project [7], developed passive and active arm supports for individuals with DMD [8]. Currently, the Symbionics 2.1 [9] explored the feasibility of an active support for the trunk and the neck of individuals with DMD. ...
... Physical Function -Despite the high clinical heterogeneity that is present in the progression of individuals with DMD [26], according to Lobo-Prat [8] there is a disease progression pattern (Figure 1.1). The main components of this pattern include the early onset of ambulatory difficulties around the age of 5-6 and the loss of independent ambulation by the age of 12-14 [17]. ...
... If contractures in the lower extremity are not severe, a passive standing device or a power standing wheelchair can be used to enhance mobility [31]. When deformations occur in the spine, due to wheelchair confinement, trunk orthoses or custom-made back rests for wheelchairs are recommended [8]. ...
Thesis
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The hand is a very complex and versatile tool, which allows humans to interact with their immediate environment, engage in daily life activities and socialize. Individuals with Duchenne muscular dystrophy (DMD), experience years of deteriorated hand function, leading to severe dependence on caregivers. Robotic exoskeletons can provide a feasible solution for the active hand support of individuals with DMD. My work describes the development of a hand exoskeleton that meets the specific needs of individuals with DMD, in order to raise their quality of life and social participation and acceptance. To this end, in the Symbionics project we developed the SymbiHand orthosis; an active wearable hand exoskeleton for people with DMD. My role in this project was the characterization of the hand neuro-motor function in DMD and the development and application of robust hand motor intention decoding, for the control of the SymbiHand.
... Additionally, individuals with DMD need robotic devices for daily assistance and for a significant amount of time [81]. In recent years robotic devices to support the arm [82], the trunk [83,84], and the hand [85,86] of people with DMD were developed and tested with promising results. Novel sensors were used [84,85] in integration with novel robotic designs [83,86] to achieve robust interfacing between the user and the robotic device. ...
... Current studies for the use of robotic exoskeletons in DMD are not many and are limited by a small number of participants [82,87]. More extensive longitudinal studies can give further insights into how DMD affects motor control in different individuals with high functional heterogeneity [88]. ...
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The only book that covers in detail a broad range of cutting-edge topics within motor rehabilitation technology Neural engineering is a discipline that uses engineering techniques to understand, repair, replace, enhance, or treat diseases of neural systems. This book describes state-of-the-art methods within this field, from brain-computer interfaces to spinal and cortical plasticity. Touching on electrode design, signal processing, the neurophysiology of movement, robotics, and much more, this innovative book presents the latest information for readers working in biomedical engineering. Each section of Introduction to Neural Engineering for Motor Rehabilitation begins with an overview of techniques before moving on to provide information on the most recent findings. Topics include: INJURIES OF THE NERVOUS SYSTEM-including diseases and injuries of the central nervous system leading to sensory-motor impairment; peripheral and spinal plasticity after nerve injuries; and motor control modules of human movement in health and disease SIGNAL DETECTION AND CONDITIONING-including progress in peripheral neural interfaces; multi-modal, multi-site neuronal recordings for brain research; methods for non-invasive electroencephalograph detection; wavelet denoising and conditioning of neural recordings FUNCTION REPLACEMENT (Prostheses and Orthosis)-including an introduction to upper limb prosthetics; controlling prostheses using peripheral nerve stimulation invasive interfaces for amputees; and exoskeletal robotics for functional substitution FUNCTION RESTORATION-including methods for movement restoration; advanced user interfaces for upper limb functional electrical stimulation; and selectivity of peripheral neural interfaces REHABILITATION THROUGH NEUROMODULATION-including brain-computer interface applied to motor recovery after brain injury; functional electrical therapy of upper extremities; and robotic assisted neurorehabilitation Introduction to Neural Engineering for Motor Rehabilitation is an important textbook and reference for graduate students and researchers in the fields of biomedical and neural engineering. © 2013 The Institute of Electrical and Electronics Engineers, Inc. All rights reserved.
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