Posts Tagged ADL

[ARTICLE] Transcranial Direct Current Stimulation Does Not Affect Lower Extremity Muscle Strength Training in Healthy Individuals: A Triple-Blind, Sham-Controlled Study – Full Text

The present study investigated the effects of anodal transcranial direct current stimulation (tDCS) on lower extremity muscle strength training in 24 healthy participants. In this triple-blind, sham-controlled study, participants were randomly allocated to the anodal tDCS plus muscle strength training (anodal tDCS) group or sham tDCS plus muscle strength training (sham tDCS) group. Anodal tDCS (2 mA) was applied to the primary motor cortex of the lower extremity during muscle strength training of the knee extensors and flexors. Training was conducted once every 3 days for 3 weeks (7 sessions). Knee extensor and flexor peak torques were evaluated before and after the 3 weeks of training. After the 3-week intervention, peak torques of knee extension and flexion changed from 155.9 to 191.1 Nm and from 81.5 to 93.1 Nm in the anodal tDCS group. Peak torques changed from 164.1 to 194.8 Nm on extension and from 78.0 to 85.6 Nm on flexion in the sham tDCS group. In both groups, peak torques of knee extension and flexion significantly increased after the intervention, with no significant difference between the anodal tDCS and sham tDCS groups. In conclusion, although the administration of eccentric training increased knee extensor and flexor peak torques, anodal tDCS did not enhance the effects of lower extremity muscle strength training in healthy individuals. The present null results have crucial implications for selecting optimal stimulation parameters for clinical trials.

Introduction

Transcranial direct current stimulation (tDCS) is a non-invasive cortical stimulation procedure in which weak direct currents polarize target brain regions (Nitsche and Paulus, 2000). The application of anodal tDCS to the primary motor cortex of the lower extremity transiently increases corticospinal excitability in healthy individuals (Jeffery et al., 2007Tatemoto et al., 2013) and improves motor function in healthy individuals and patients with stroke (Tanaka et al., 20092011Madhavan et al., 2011Sriraman et al., 2014Chang et al., 2015Montenegro et al., 20152016Angius et al., 2016Washabaugh et al., 2016). Thus, anodal tDCS has a potential to become a new adjunct therapeutic strategy for the rehabilitation of leg motor function and locomotion following a stroke.

Lower leg muscle strength is an important motor function required for patients who have had a stroke to regain activities of daily living (ADL). Lower leg muscle strength correlates with performance in activities, including sit-to-stand, gait, and stair ascent (Bohannon, 2007). Furthermore, lower leg muscle strength training increases muscle strength and improves ADL in patients with stroke (Ada et al., 2006). Therefore, lower leg muscle strength training is one of the important activities rehabilitating patients with stroke to regain their independence in ADL.

Several studies have examined the effect of a single session of tDCS on lower leg muscle strength, although the evidence is inconsistent (Tanaka et al., 20092011Montenegro et al., 20152016Angius et al., 2016Washabaugh et al., 2016). Its effects seem dependent on tDCS protocols, training tasks, muscle groups, and subject populations. Although, most tDCS studies on lower leg muscle strength have focused on the acute effects of a single tDCS application, to the best of our knowledge, no study has examined how lower extremity strength training combined with repeated sessions of tDCS affects lower leg muscle strength. This type of investigation has strong clinical implications for the application of tDCS in rehabilitation for patients with lower leg muscle weakness.

Thus, to examine whether anodal tDCS can enhance the effects of lower extremity muscle strength training, the present study simultaneously applied anodal tDCS and lower extremity muscle strength training to healthy individuals and evaluated their effects on lower extremity muscle strength.

Continue —> Frontiers | Transcranial Direct Current Stimulation Does Not Affect Lower Extremity Muscle Strength Training in Healthy Individuals: A Triple-Blind, Sham-Controlled Study | Perception Science

Figure 1. Experimental setup of the muscle strength training and torque assessment.

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[Conference paper] Upper-Limb Kinematics During Feeding and Drinking – Abstract+References

Abstract

Feeding and drinking are Activities of Daily Living which can be used to assess the motor control and functional ability of the upper limb. This paper presents the upper-limb kinematics during the execution of feeding and drinking activities, such analysis consisted in the measurement of angles of flexion for trunk and arm. Eight healthy subjects performed these activities in a simulated-environment while they were video recorded. Markers on anatomical landmarks were used to analyze the kinematics of the upper limb in the sagittal plane. Additionally an electro-hydraulic sensor was attached to each upper limb to assess the vertical position of the wrist relative to the shoulder. Results showed a difference on the angles of the elbow and trunk. The electro-hydraulic sensor showed to be an efficient way to record the vertical position of wrist.

References

Source: Upper-Limb Kinematics During Feeding and Drinking | SpringerLink

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[VIDEO] SaeboVR – World’s First Virtual ADL Rehabilitation System

Δημοσιεύτηκε στις 21 Φεβ 2017

Saebo, Inc., is a leading global provider of innovative rehabilitation products for stroke survivors and other neurologically impaired individuals. Headquartered in Charlotte, NC, the company was founded in 2001 by two occupational therapists specializing in stroke rehabilitation. As the leading cause of long-term disability in the U.S., stroke affects over 700,000 Americans every year, leaving many with crippling side affects including the loss of hand function. Saebos pioneering treatment protocols are based on new research documenting the brains remarkable ability to re-program itself following injury.

The companys neurological orthotic devices, including the ground-breaking SaeboFlex and SaeboReach, allow patients with very little residual arm and hand function to immediately begin performing task-oriented, grasp and release activities, thereby forging new pathways in the brain. Named Most Valuable Product in 2008 by Therapy Times, the Saebo Program is now offered as a treatment option at over 2,000clinics and hospitals nationwide, including 22 of the Top 25 Rehabilitation Hospitals as ranked by U.S. News & World Report. The Saebo orthoses are also eligible for reimbursement by Medicare and most commercial insurers. With a network of over 6,000 trained clinicians spanning four continents, Saebo is committed to helping stroke survivors around the globe achieve a new level of independence.

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[ARTICLE] Perceived ability to perform daily hand activities after stroke and associated factors: a cross-sectional study – Full Text

Abstract

Background

Despite that disability of the upper extremity is common after stroke, there is limited knowledge how it influences self-perceived ability to perform daily hand activities. The aim of this study was to describe which daily hand activities that persons with mild to moderate impairments of the upper extremity after stroke perceive difficult to perform and to evaluate how several potential factors are associated with the self-perceived performance.

Methods

Seventy-five persons (72 % male) with mild to moderate impairments of the upper extremity after stroke (4 to 116 months) participated. Self-perceived ability to perform daily hand activities was rated with the ABILHAND Questionnaire. The perceived ability to perform daily hand activities and the potentially associated factors (age, gender, social and vocational situation, affected hand, upper extremity pain, spasticity, grip strength, somatosensation of the hand, manual dexterity, perceived participation and life satisfaction) were evaluated by linear regression models.

Results

The activities that were perceived difficult or impossible for a majority of the participants were bimanual tasks that required fine manual dexterity of the more affected hand. The factor that had the strongest association with perceived ability to perform daily hand activities was dexterity (p < 0.001), which together with perceived participation (p = 0.002) explained 48 % of the variance in the final multivariate model.

Conclusion

Persons with mild to moderate impairments of the upper extremity after stroke perceive that bimanual activities requiring fine manual dexterity are the most difficult to perform. Dexterity and perceived participation are factors specifically important to consider in the rehabilitation of the upper extremity after stroke in order to improve the ability to use the hands in daily life.

Background

Disability of the upper extremity is common after stroke and almost 50 % of those affected have remaining impairments more than three months post-stroke [1, 2]. The impairments often lead to difficulties in performing daily hand activities [3], especially those that require the use of both hands, i.e., bimanual activities [4]. The ability to perform bimanual activities is therefore an important goal in stroke rehabilitation, regardless of which hand that is affected [5].

The ability to perform daily activities can be objectively assessed by observations of different tasks in a standardized environment or by patient-reported questionnaires. The advantage of using questionnaires is that they often provide a better understanding of an individual’s self-reported everyday difficulties and thereby enable clinicians to design more individually targeted rehabilitation interventions [6]. One questionnaire that is recommended for persons with disability of the upper extremity after stroke is the ABILHAND Questionnaire [4, 7, 8]. It assesses self-perceived ability to perform daily bimanual activities. Previous studies have focused on evaluating the psychometric properties of the ABILHAND [4, 8], but no study has thoroughly described which activities persons in a stable phase post stroke perceive difficult to perform.

In order to improve functioning of the upper extremity after stroke, it is important to understand which factors affect self-perceived ability to perform daily hand activities. Previous studies have shown that single factors, such as motor function, muscle strength, spasticity, somatosensation, dexterity, perceived participation and life satisfaction are moderately to strongly associated with the perceived ability [4, 9, 10, 11, 12, 13, 14, 15, 16, 17]. However, as several factors simultaneously may influence the ability to perform daily hand activities there is a need to understand how these factors are associated with the performance. To the best of our knowledge, only one study [14] has evaluated this association in persons in a stable phase after stroke. In that study by Harris and Eng [14], muscle strength, spasticity, somatosensation and pain were included in multivariate analyses and the authors found that muscle strength in the upper extremity and spasticity were the strongest contributing factors to the perceived ability to use the hands in daily activities. However, dexterity was omitted as a potentially associated factor in the analysis, which was addressed as a limitation of the study. In other studies, gender, dominance of the affected upper extremity, and social and vocational situations have been shown to be important factors for overall functioning after stroke [18, 19, 20, 21]. However, it is unclear how these factors are associated with the self-perceived ability.

Taken together, despite that disability of the upper extremity is common after stroke there is limited knowledge of which daily activities that are perceived difficult to perform and which factors that affect the self-perceived performance. The majority of previous studies have evaluated how single or few factors are associated with perceived daily hand activities. Thus, there is a need for more studies that take several factors into account simultaneously.

The aim of this study was to evaluate a) which daily activities persons with mild to moderate impairments of the upper extremity after stroke perceive difficult to perform and b) how several factors (age, gender, social and vocational situation, affected hand, upper extremity pain, spasticity, grip strength, somatosensation, manual dexterity, perceived participation and life satisfaction) are associated with the self-perceived performance.

Source: Perceived ability to perform daily hand activities after stroke and associated factors: a cross-sectional study | BMC Neurology | Full Text

Fig. 1 Study flowchart

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[ARTICLE] Effectiveness of upper limb functional electrical stimulation after stroke for the improvement of activities of daily living and motor function: a systematic review and meta-analysis – Full Text

Abstract

Background

Stroke can lead to significant impairment of upper limb function which affects performance of activities of daily living (ADL). Functional electrical stimulation (FES) involves electrical stimulation of motor neurons such that muscle groups contract and create or augment a moment about a joint. Whilst lower limb FES was established in post-stroke rehabilitation, there is a lack of clarity on the effectiveness of upper limb FES. This systematic review aims to evaluate the effectiveness of post-stroke upper limb FES on ADL and motor outcomes.

Methods

Systematic review of randomised controlled trials from MEDLINE, PsychINFO, EMBASE, CENTRAL, ISRCTN, ICTRP and ClinicalTrials.gov. Citation checking of included studies and systematic reviews. Eligibility criteria: participants > 18 years with haemorrhagic/ischaemic stroke, intervention group received upper limb FES plus standard care, control group received standard care. Outcomes were ADL (primary), functional motor ability (secondary) and other motor outcomes (tertiary). Quality assessment using GRADE (Grading of Recommendations Assessment, Development and Evaluation) criteria.

Results

Twenty studies were included. No significant benefit of FES was found for objective ADL measures reported in six studies (standardised mean difference (SMD) 0.64; 95% Confidence Interval (CI) [−0.02, 1.30]; total participants in FES group (n) = 67); combination of all ADL measures was not possible. Analysis of three studies where FES was initiated on average within 2 months post-stroke showed a significant benefit of FES on ADL (SMD 1.24; CI [0.46, 2.03]; n = 32). In three studies where FES was initiated more than 1 year after stroke, no significant ADL improvements were seen (SMD −0.10; CI [−0.59, 0.38], n = 35).

Quality assessment using GRADE found very low quality evidence in all analyses due to heterogeneity, low participant numbers and lack of blinding.

Conclusions

FES is a promising therapy which could play a part in future stroke rehabilitation. This review found a statistically significant benefit from FES applied within 2 months of stroke on the primary outcome of ADL. However, due to the very low (GRADE) quality evidence of these analyses, firm conclusions cannot be drawn about the effectiveness of FES or its optimum therapeutic window. Hence, there is a need for high quality large-scale randomised controlled trials of upper limb FES after stroke.

Background

Stroke is defined as a clinical syndrome characterised by rapidly developing focal or global disturbance in cerebral function lasting more than 24 h or leading to death due to a presumed vascular cause [1]. Globally, approximately 16 million people have a stroke each year [2] and in the UK, first-ever stroke affects about 230 people per 100,000 population each year [3]. Stroke represents a cost to the UK economy of approximately £9 billion annually, of which £1.33 billion results from productivity losses [4].

Stroke often leads to significant impairment of upper limb function and is associated with decreased quality of life in all domains except for mobility [5]. Few patients attain complete functional recovery [6]; this deficit impairs performance of activities of daily living (ADL), including self-care and social activities [7, 8]. ADL reflect the level of functional impairment in daily life and are therefore the most clinically relevant outcome measures in assessing recovery after stroke [9].

Functional electrical stimulation (FES) was well established as an intervention for motor rehabilitation. FES is the electrical stimulation of motor neurons such that muscle groups are stimulated to contract and create/augment a moment about a joint [2]. Transcutaneous electrodes offer the most immediate and clinically viable treatment option as they are non-invasive and may permit home-based treatment.

There are various terms used in the literature to describe different forms of electrical stimulation, often inconsistently. Some authors define FES as electrical stimulation applied to a subject which causes muscle contraction. This passive modality is also referred to as neuromuscular electrical stimulation [10]. Others define FES as electrical stimulation applied during a voluntary movement [4]. This definition acknowledges the volitional component of physical rehabilitation and was used in this systematic review. The distinction is important because neuroimaging studies have identified different cortical mechanisms according to stimulation type [11, 12, 13]. Indeed, perfusion to the ipsilesional sensory-motor cortex and cortical excitability were increased with FES when compared to passive modalities of electrical stimulation [12, 13, 14]. These findings could indicate greater potential for volitional FES to induce neuroplasticity. This is believed to play an important role in neurorehabilitation [15] and is a key objective of post-stroke functional recovery [16].

FES has been widely researched for post-stroke lower limb rehabilitation; several systematic reviews [17, 18, 19] and national guidelines [20, 21] exist. Improvement in upper limb function is central to post-stroke rehabilitation as it positively affects ADL and quality of life [22]. Yet, there is still a lack of clarity on the effectiveness of FES in post-stroke upper limb rehabilitation [23] despite systematic reviews having been undertaken [24, 25, 26, 27, 28]. In part, this is due to methodological limitations [27, 28] or the outdated nature of some existing reviews [24, 25, 26]. The latter was highlighted by a recent Cochrane overview of reviews calling for an up-to-date review and meta-analysis of randomised controlled trials (RCTs) related to electrical stimulation [29]. A more recent systematic review found a significant improvement in motor outcomes with upper limb FES [27]. However, this was based on a single meta-analysis that combined ADLs with upper limb-specific measures of functional motor ability, including studies where results were at risk of performance bias (intervention groups receiving greater duration of treatment than control groups) [27]. Another found no improvement in motor function when FES was applied within 6 months of stroke [28]. However, this predominantly included studies that applied electrical stimulation in the absence of volitional muscle contraction, confounding interpretation of the results. This inconsistency is reflected in the 2016 guidelines set by the Royal College of Physicians which recommends FES only in the context of clinical trials as an adjunct to conventional therapy [21].

This systematic review aims to elucidate the effectiveness of upper limb FES compared to standard therapy in improving ADL, in addition to motor outcomes, post-stroke. It represents an important addition to the literature that focuses on the use of volitional FES and, for the first time, distinguishes its effect on clinically relevant patient outcomes from surrogate markers of patient rehabilitation. This includes analyses based on patient sub-groups defined by the time after stroke at which FES was initiated.

Fig. 1 Flow diagram for included studies

Continue —> Effectiveness of upper limb functional electrical stimulation after stroke for the improvement of activities of daily living and motor function: a systematic review and meta-analysis | Systematic Reviews | Full Text

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[ARTICLE] Effects of two-handed task training on upper limb function of chronic hemiplegic patients after stroke – Full Text PDF

Abstract.

[Purpose] The purpose of this study was to determine whether two-handed task training is effective on motor learning of injured cerebral cortex activation and upper extremity function recovery after stroke.

[Subjects and Methods] Two hemiplegic subjects participated in this study: one patient was affected on the dominant side of the body and the other was affected on the non-dominant side of the body, and both scored in the range of 58–66 in the Fugl-Meyer assessment. The excitability of the corticospinal tract and Manual Function Test were examined.

[Results] The excitability of the corticospinal tract and the Manual Function Test showed significant differences in the activation of both sides of the cerebral cortex and in the variation in learning effect of upper extremity motor function recovery in patients with hemiplegic non-dominant hand (left).

[Conclusion] The results suggested that two-handed task training had a different influence on dominant hand (right) and non-dominant hand (left) motor recovery.

INTRODUCTION

The dominant hand is defined as the hand that is usually used in performing activities of daily living (ADL). The development of the motor function of the cerebral cortex is asymmetrical to the dominant hand1) . Based on such asymmetrical development of the cerebral cortex, when the left hand is performing a task, the cerebral cortex motor area of the right cerebral hemisphere activates. However, a more interesting fact is that when the right hand is used functionally, the nerve cells of the entire cerebral cortex motor area of the right and left cerebral hemispheres activate2) . This finding supports the evidence of lateralization of the cerebral hemisphere and implies that the left cerebral hemisphere acts the role of the dominant cerebral hemisphere when performing ADL2, 3) . Thus, the left hemisphere, which is the dominant cerebral hemisphere due to the lateralization of the cerebral hemisphere, is more closely related with motor planning in ADL performance, and the same relationships were shown after cerebral hemisphere injury due to stroke3, 4) . Characteristically, the patient with stroke-damaged dominant left cerebral hemisphere reports a time delay on the exercise performance of both right and left hands, whereas the patient with damaged right cerebral hemisphere reports a mild motor function disorder confined to the left hand3) . This means that, consequently, after stroke onset, the patient with hemiplegic dominant hand (right) experiences more difficulty in performing ADL5) . However, regarding upper extremity rehabilitation, there is no study that differentiated the motor function recovery of the upper extremity of patients who are affected in the dominant cerebral hemisphere (with the hemiplegic right hand) or in the non-dominant cerebral hemisphere (with the hemiplegic left hand). A specific rehabilitation approach based on laterality through classification of cerebral damage on the right or left side is needed to achieve a more successful rehabilitation of the upper extremity. Thus, the purpose of this study is to determine whether two-handed task training is effective in the motor learning of the injured cerebral cortex activation and upper extremity function recovery after stroke.

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[ARTICLE] Feasibility Analysis Of Daily Activities Using Assistive Robotic Manipulators – Full Text

ABSTRACT

In the United States, more than 21.5 million people report a limitation in their self-care activities and independent living. Assistive robotic manipulators (ARMs) can provide assistance with daily tasks for people with upper extremity impairments. Previous studies have evaluated ARM efficacy in completing single and multiple action tasks. This paper presents the feasibility analysis of two sequential daily self-care activities, brushing teeth and preparing and then eating a simple meal. The two tasks were successfully completed by a well-trained investigator using the ARM. By analyzing the difficulties and failures in the testing, the ARM’s kinematic and dynamic limitations and the kinesthetic perceptions made it difficult to re-adjust motion planning before errors occurred. In addition, we provide an example to alleviate environmental limitations. Due to the differences between the ARM and human motions, some intuitive human motion plans were not applicable to the ARM motion. The results of this work may help researchers and clinicians develop appropriate accessories, make adequate environmental adjustments, and tailor training for ARM users.

BACKGROUND

In the United States, more than 21.5 million people report limitations in the self-care activities and independent living (Erickson, Lee, & von Schrader, 2014), such as dressing and eating and doing errands alone. In addition, a growing older adult population with moderate to severe disabilities is estimated to reach 24.6 million people in 2040 (Johnson, 2007). Assistive robot manipulators (ARMs) have emerged as a tool to assist with activities of daily living (ADLs) (Allin, Eckel, Markham, & Brewer, 2010). Commercial ARMs such as iARM by the Exact Dynamics (Dindom, The Netherlands) and JACO by Kinova (Montreal, Canada), were developed to assist people with upper extremity impairments with manipulation tasks in their daily living and increase their independence (Driessen, Evers, & Van Woerden, 2001; Maheu, Archambault, Frappier, & Routhier, 2011).

The adaptation of new assistive technologies requires not only a solid understanding of the interface but also new ways in performing tasks. For example, a new power wheelchair user has to learn not only the joystick control interface but also develop new strategies to move around places due to the limitation of the mobility device. Similarly, better ARM performance relies on both the efficient control interface and fluid motion planning. Studies evaluated the ARM control efficiency using various levels of ADL tasks: single action, multiple actions, and sequential tasks (Chung, Wang, & Cooper, 2013), shown in Table 1. These studies evaluated ARM performance using single or multiple action tasks, such as pick-and-place and pushing buttons and evaluated users’ abilities with different control interfaces. However, most ADL tasks are sequential, which are the combinations of successful completion of single and multiple actions in a suitable sequence. A complete eating sequence includes not only scooping of food and placing a spoon in the mouth but also applying different motion plans to collect food from different locations in the bowl.

Several studies (Chung, Hannan, Wang, Kelleher, & Cooper, 2014; Chung, Wang, Kelleher, & Cooper, 2013) were conducted to evaluate the ARM efficacy with standardized performance evaluation tools that can minimize environmental variability so that performance from different studies can be easily contrasted or compared. These studies revealed statistical differences in the efficacy of ARM performance across tasks. Noticeably, better performance on the standardized tools may lead to less errors and faster performance in the sequential tasks. However, most ARM studies were evaluated in lab settings. The feasibility using common objects within ordinary environments remains to be determined. Additionally, few studies have reported the limitations and challenges of ARM performance under real life situations.

Thus, in this study, we assessed the feasibility of two sequential self-care tasks, brushing teeth and preparing and then eating a simple meal. Successful motion planning in conjunction with the limitations and challenges under real life situations were examined to help researchers and clinicians develop appropriate accessories and make adequate environmental adjustments for ARM users.

Figure 1. Two sequential tasks (Left: brushing teeth, Right: preparing and then having a simple meal)

Continue —> Feasibility Analysis Of Daily Activities Using Assistive Robotic Manipulators

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[ARTICLE] Hybrid EEG/EOG-based brain/neural hand exoskeleton restores fully independent daily living activities after quadriplegia – Full Text

Abstract

Direct brain control of advanced robotic systems promises substantial improvements in health care, for example, to restore intuitive control of hand movements required for activities of daily living in quadriplegics, like holding a cup and drinking, eating with cutlery, or manipulating different objects. However, such integrated, brain- or neural-controlled robotic systems have yet to enter broader clinical use or daily life environments. We demonstrate full restoration of independent daily living activities, such as eating and drinking, in an everyday life scenario across six paraplegic individuals (five males, 30 ± 14 years) who used a noninvasive, hybrid brain/neural hand exoskeleton (B/NHE) to open and close their paralyzed hand. The results broadly suggest that brain/neural-assistive technology can restore autonomy and independence in quadriplegic individuals’ everyday life.

INTRODUCTION

Quadriplegia, the loss of motor function of both arms and legs, is often caused by traumatic cervical spinal cord injury (SCI) affecting 1 in 10,000 people worldwide (1, 2). Although SCI is associated with lower life expectancy and quality of life (3, 4), it typically affects younger individuals, leading to substantial loss of their independence and autonomy. Regaining hand and arm function was identified as the most critical need in this population (5). Although SCI remains an incurable condition with most treatment approaches aimed at minimizing secondary medical complications and maximizing residual function, the development of brain-machine interfaces (BMIs) has recently fueled hope that by bypassing the lesioned spinal system, independence and autonomy of individuals with severe paralysis could be restored (69). In particular, the possibility that repeated use of such BMI-based bypass could trigger neurological recovery despite clinically complete and chronic SCI (10) points to new avenues in the treatment of severe paralysis that build on fostering neuroplasticity through direct brain- or neural-robot interactions. BMIs translate electric, magnetic, or metabolic brain activity (e.g., associated with the intention to reach and grasp) into control signals of external machines, exoskeletons, or robots (11). Because mental imagery (e.g., the visualization of a closing hand) results in an actual hand-closing motion performed by a robotic device or exoskeleton in such a paradigm, BMI control is particularly intuitive.

Although implantable BMIs have recently been shown to allow versatile control of a robotic arm in patients with chronic quadriplegia (8, 12, 13), the required craniotomy entails the risk of surgical complications, for example, infections or bleedings. Also, implantable systems have to be explanted after some time, posing an ethical and clinical dilemma. Thus, implantation of a BMI for controlling such versatile robots is mainly attractive for individuals who are completely paralyzed, for example, after severe brainstem stroke or in the late stage of a neurodegenerative disease.

To date, we know of no patient who has used a BMI outside the laboratory to perform activities of daily living (ADLs), for example, having a full meal in an outside restaurant. The main obstacle for such application relates to the nonstationarity of brain activity and susceptibility to environmental artifacts, particularly in noninvasive brain activity recordings that provide lower signal-to-noise ratios compared with invasive recordings (14). Thus, hybrid systems that combine BMI technology with other biosignals (1517) or eye gaze (18, 19) to improve system control have been proposed. Previous work demonstrated that the combination of electroencephalography (EEG) and electrooculography (EOG) can be used for hand exoskeleton control in healthy volunteers under laboratory conditions (16, 17). The translational value of this approach for restoration of hand function in real-life environments after quadriplegia, a condition for which there is currently no effective treatment, was not known. Here, we address this question and show the restoration of fully independent ADLs, such as eating and drinking, across six quadriplegic individuals with cervical SCI.

Study participants used a noninvasive brain/neural hand exoskeleton (B/NHE) that translates brain electric signals accompanying the intention to grasp into actual exoskeleton-driven hand-closing motions and EOG signals related to voluntary horizontal eye movements [horizontal oculoversions (HOVs)] into exoskeleton-driven hand-opening motions (Figs. 1 and 2). The participants were asked to perform self-initiated reaching and grasping actions, for example, eating and drinking in a nearby restaurant and outdoors. The ability to grasp and manipulate daily life objects was assessed using the Toronto Rehabilitation Institute–Hand Function Test (TRI-HFT) with and without the B/NHE system. Reliability, tolerability, and practicability to perform ADLs were rated by each participant after the end of the session.

Fig. 1 Scheme of process pipeline to control the hand exoskeleton. EEG and EOG signals were transmitted to a wireless tablet computer performing real-time signal processing and translation into control signals sent to a control box and actuators moving the hand exoskeleton via a flexible cable sheath system.

 

Fig. 2 Design of hybrid biosignal processing for reliable hand exoskeleton control. Signals related to the detection of HOVs and intention to grasp as measured by electrooculographic (A) and brain electric (B) activity were used for the hybrid BMI hand exoskeleton control (C). Hand exoskeleton closing movements were initiated by the detection of SMR-ERD, whereas hand exoskeleton opening movements were controlled by HOVs’ EOG activity exceeding the eye movement detection threshold [red dashed line in (A)]. In case EOG activity exceeded the eye movement detection threshold during SMR-ERD [indicated by the red dashed rectangle in (B)], the hand exoskeleton opened, and brain control was blocked for 1.5 s [indicated by the red rectangles in (C)] to ensure safety during performing daily life actions.

Continue —> Hybrid EEG/EOG-based brain/neural hand exoskeleton restores fully independent daily living activities after quadriplegia | Science Robotics

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[ARTICLE] Perceived ability to perform daily hand activities after stroke and associated factors: a cross-sectional study – Full Text

Abstract

Background

Despite that disability of the upper extremity is common after stroke, there is limited knowledge how it influences self-perceived ability to perform daily hand activities. The aim of this study was to describe which daily hand activities that persons with mild to moderate impairments of the upper extremity after stroke perceive difficult to perform and to evaluate how several potential factors are associated with the self-perceived performance.

Methods

Seventy-five persons (72 % male) with mild to moderate impairments of the upper extremity after stroke (4 to 116 months) participated. Self-perceived ability to perform daily hand activities was rated with the ABILHAND Questionnaire. The perceived ability to perform daily hand activities and the potentially associated factors (age, gender, social and vocational situation, affected hand, upper extremity pain, spasticity, grip strength, somatosensation of the hand, manual dexterity, perceived participation and life satisfaction) were evaluated by linear regression models.

Results

The activities that were perceived difficult or impossible for a majority of the participants were bimanual tasks that required fine manual dexterity of the more affected hand. The factor that had the strongest association with perceived ability to perform daily hand activities was dexterity (p < 0.001), which together with perceived participation (p = 0.002) explained 48 % of the variance in the final multivariate model.

Conclusion

Persons with mild to moderate impairments of the upper extremity after stroke perceive that bimanual activities requiring fine manual dexterity are the most difficult to perform. Dexterity and perceived participation are factors specifically important to consider in the rehabilitation of the upper extremity after stroke in order to improve the ability to use the hands in daily life.

Background

Disability of the upper extremity is common after stroke and almost 50 % of those affected have remaining impairments more than three months post-stroke [1, 2]. The impairments often lead to difficulties in performing daily hand activities [3], especially those that require the use of both hands, i.e., bimanual activities [4]. The ability to perform bimanual activities is therefore an important goal in stroke rehabilitation, regardless of which hand that is affected [5].

The ability to perform daily activities can be objectively assessed by observations of different tasks in a standardized environment or by patient-reported questionnaires. The advantage of using questionnaires is that they often provide a better understanding of an individual’s self-reported everyday difficulties and thereby enable clinicians to design more individually targeted rehabilitation interventions [6]. One questionnaire that is recommended for persons with disability of the upper extremity after stroke is the ABILHAND Questionnaire [4, 7, 8]. It assesses self-perceived ability to perform daily bimanual activities. Previous studies have focused on evaluating the psychometric properties of the ABILHAND [4, 8], but no study has thoroughly described which activities persons in a stable phase post stroke perceive difficult to perform.

In order to improve functioning of the upper extremity after stroke, it is important to understand which factors affect self-perceived ability to perform daily hand activities. Previous studies have shown that single factors, such as motor function, muscle strength, spasticity, somatosensation, dexterity, perceived participation and life satisfaction are moderately to strongly associated with the perceived ability [4, 9, 10, 11, 12, 13, 14, 15, 16, 17]. However, as several factors simultaneously may influence the ability to perform daily hand activities there is a need to understand how these factors are associated with the performance. To the best of our knowledge, only one study [14] has evaluated this association in persons in a stable phase after stroke. In that study by Harris and Eng [14], muscle strength, spasticity, somatosensation and pain were included in multivariate analyses and the authors found that muscle strength in the upper extremity and spasticity were the strongest contributing factors to the perceived ability to use the hands in daily activities. However, dexterity was omitted as a potentially associated factor in the analysis, which was addressed as a limitation of the study. In other studies, gender, dominance of the affected upper extremity, and social and vocational situations have been shown to be important factors for overall functioning after stroke [18, 19, 20, 21]. However, it is unclear how these factors are associated with the self-perceived ability.

Taken together, despite that disability of the upper extremity is common after stroke there is limited knowledge of which daily activities that are perceived difficult to perform and which factors that affect the self-perceived performance. The majority of previous studies have evaluated how single or few factors are associated with perceived daily hand activities. Thus, there is a need for more studies that take several factors into account simultaneously.

The aim of this study was to evaluate a) which daily activities persons with mild to moderate impairments of the upper extremity after stroke perceive difficult to perform and b) how several factors (age, gender, social and vocational situation, affected hand, upper extremity pain, spasticity, grip strength, somatosensation, manual dexterity, perceived participation and life satisfaction) are associated with the self-perceived performance.

Continue —> Perceived ability to perform daily hand activities after stroke and associated factors: a cross-sectional study | BMC Neurology | Full Text

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