Standardized Measurement of Quality of Upper Limb Movement After Stroke: Consensus-Based Core Recommendations From the Second Stroke Recovery and Rehabilitation Roundtable.

The second Stroke Recovery and Rehabilitation Roundtable "metrics" task force developed consensus around the recognized need to add kinematic and kinetic movement quantification to its core recommendations for standardized measurements of sensorimotor recovery in stroke trials. Specifically, we focused on measurement of the quality of upper limb movement. We agreed that the recommended protocols for measurement should be conceptually rigorous, reliable, valid and responsive to change. The recommended measurement protocols include four performance assays (i.e. 2D planar reaching, finger individuation, grip strength, and precision grip at body function level) and one functional task (3D drinking task at activity level) that address body function and activity respectively. This document describes the criteria for assessment and makes recommendations about the type of technology that should be used for reliable and valid movement capture. Standardization of kinematic measurement protocols will allow pooling of participant data across sites, thereby increasing sample size aiding meta-analyses of published trials, more detailed exploration of recovery profiles, the generation of new research questions with testable hypotheses, and development of new treatment approaches focused on impairment. We urge the clinical and research community to consider adopting these recommendations.

Standardized measurement of quality of upper limb movement after stroke: Consensus-based core recommendations from the Second Stroke Recovery and Rehabilitation Roundtable.

The second Stroke Recovery and Rehabilitation Roundtable "metrics" task force developed consensus around the recognized need to add kinematic and kinetic movement quantification to its core recommendations for standardized measurements of sensorimotor recovery in stroke trials. Specifically, we focused on measurement of the quality of upper limb movement. We agreed that the recommended protocols for measurement should be conceptually rigorous, reliable, valid and responsive to change. The recommended measurement protocols include four performance assays (i.e. 2D planar reaching, finger individuation, grip strength, and precision grip at body function level) and one functional task (3D drinking task at activity level) that address body function and activity respectively. This document describes the criteria for assessment and makes recommendations about the type of technology that should be used for reliable and valid movement capture. Standardization of kinematic measurement protocols will allow pooling of participant data across sites, thereby increasing sample size aiding meta-analyses of published trials, more detailed exploration of recovery profiles, the generation of new research questions with testable hypotheses, and development of new treatment approaches focused on impairment. We urge the clinical and research community to consider adopting these recommendations.

A qualitative study exploring views and experiences of people with stroke undergoing transcranial direct current stimulation and upper limb robot therapy.

Background Neurorehabilitation technologies used mainly in research such as robot therapy (RT) and transcranial direct current stimulation (tDCS) can promote upper limb motor recovery after stroke. Understanding the feasibility and efficacy of stroke rehabilitation technologies for upper limb impairments is crucial for effective implementation in practice. Small studies have explored views of RT by people with stroke; however experiences of people receiving tDCS in combination with RT have never been explored. Objective To explore views and experiences of people with sub-acute and chronic stroke that had previously taken part in a randomised controlled trial involving tDCS and RT for their impaired upper limb. Methods An interview study includes open and closed questions. Face-to-face interviews were audio recorded. Open-ended question responses were transcribed and analyzed using thematic analysis; closed questions were analyzed using descriptive analysis. Results Participants felt that RT was enjoyable (90%) and beneficial for their affected arm (100%). From the open question data, it was found that the intervention was effective for the impaired arm especially in the sub-acute stage. Main reported concerns were that tDCS caused painful, itching and burning sensations and RT was sometimes tiring and difficult. Participants recommended that future research should focus on designing a more comfortable method of tDCS and develop a robot that promotes hand movements. Conclusions This study provides new knowledge about the benefits and barriers associated with these technologies which are crucial to the future effective implementation of these tools in practice.

European consensus on the concepts and measurement of the pathophysiological neuromuscular responses to passive muscle stretch.

BACKGROUND AND PURPOSE: To support clinical decision-making in central neurological disorders, a physical examination is used to assess responses to passive muscle stretch. However, what exactly is being assessed is expressed and interpreted in different ways. A clear diagnostic framework is lacking. Therefore, the aim was to arrive at unambiguous terminology about the concepts and measurement around pathophysiological neuromuscular response to passive muscle stretch. METHODS: During two consensus meetings, 37 experts from 12 European countries filled online questionnaires based on a Delphi approach, followed by plenary discussion after rounds. Consensus was reached for agreement ≥75%. RESULTS: The term hyper-resistance should be used to describe the phenomenon of impaired neuromuscular response during passive stretch, instead of for example 'spasticity' or 'hypertonia'. From there, it is essential to distinguish non-neural (tissue-related) from neural (central nervous system related) contributions to hyper-resistance. Tissue contributions are elasticity, viscosity and muscle shortening. Neural contributions are velocity dependent stretch hyperreflexia and non-velocity dependent involuntary background activation. The term 'spasticity' should only be used next to stretch hyperreflexia, and 'stiffness' next to passive tissue contributions. When joint angle, moment and electromyography are recorded, components of hyper-resistance within the framework can be quantitatively assessed. CONCLUSIONS: A conceptual framework of pathophysiological responses to passive muscle stretch is defined. This framework can be used in clinical assessment of hyper-resistance and will improve communication between clinicians. Components within the framework are defined by objective parameters from instrumented assessment. These parameters need experimental validation in order to develop treatment algorithms based on the aetiology of the clinical phenomena.

Multiple sessions of transcranial direct current stimulation and upper extremity rehabilitation in stroke: A review and meta-analysis.

OBJECTIVE: To systematically review the methodology in particular treatment options and outcomes and the effect of multiple sessions of transcranial direct current stimulation (tDCS) with rehabilitation programmes for upper extremity recovery post stroke. METHODS: A search was conducted for randomised controlled trials involving tDCS and rehabilitation for the upper extremity in stroke. Quality of included studies was analysed using the Modified Downs and Black form. The extent of, and effect of variation in treatment parameters such as anodal, cathodal and bi-hemispheric tDCS on upper extremity outcome measures of impairment and activity were analysed using meta-analysis. RESULTS: Nine studies (371 participants with acute, sub-acute and chronic stroke) were included. Different methodologies of tDCS and upper extremity intervention, outcome measures and timing of assessments were identified. Real tDCS combined with rehabilitation had a small non-significant effect of +0.11 (p=0.44) and +0.24 (p=0.11) on upper extremity impairments and activities at post-intervention respectively. CONCLUSION: Various tDCS methods have been used in stroke rehabilitation. The evidence so far is not statistically significant, but is suggestive of, at best, a small beneficial effect on upper extremity impairment. SIGNIFICANCE: Future research should focus on which patients and rehabilitation programmes are likely to respond to different tDCS regimes.

A double-blinded randomised controlled trial exploring the effect of anodal transcranial direct current stimulation and uni-lateral robot therapy for the impaired upper limb in sub-acute and chronic stroke.

BACKGROUND: Neurorehabilitation technologies such as robot therapy (RT) and transcranial Direct Current Stimulation (tDCS) can promote upper limb (UL) motor recovery after stroke. OBJECTIVE: To explore the effect of anodal tDCS with uni-lateral and three-dimensional RT for the impaired UL in people with sub-acute and chronic stroke. METHODS: A pilot randomised controlled trial was conducted. Stroke participants had 18 one-hour sessions of RT (ArmeoSpring) over eight weeks during which they received 20 minutes of either real tDCS or sham tDCS during each session. The primary outcome measure was the Fugl-Meyer assessment (FMA) for UL impairments and secondary were: UL function, activities and stroke impact collected at baseline, post-intervention and three-month follow-up. RESULTS: 22 participants (12 sub-acute and 10 chronic) completed the trial. No significant difference was found in FMA between the real and sham tDCS groups at post-intervention and follow-up (p = 0.123). A significant 'time' x 'stage of stroke' was found for FMA (p = 0.016). A higher percentage improvement was noted in UL function, activities and stroke impact in people with sub-acute compared to chronic stroke. CONCLUSIONS: Adding tDCS did not result in an additional effect on UL impairment in stroke. RT may be of more benefit in the sub-acute than chronic phase.

Design & control of a 3D stroke rehabilitation platform.

An upper limb stroke rehabilitation system is developed which combines electrical stimulation with mechanical arm support, to assist patients performing 3D reaching tasks in a virtual reality environment. The Stimulation Assistance through Iterative Learning (SAIL) platform applies electrical stimulation to two muscles in the arm using model-based control schemes which learn from previous trials of the task. This results in accurate movement which maximises the therapeutic effect of treatment. The principal components of the system are described and experimental results confirm its efficacy for clinical use in upper limb stroke rehabilitation.

Constant angular velocity of the wrist during the lifting of a sphere.

The primary objective of the experiments was to investigate the wrist motion of a person while they were carrying out a prehensile task from a clinical hand function test. A six-camera movement system was used to observe the wrist motion of 10 participants. A very light sphere and a heavy sphere were used in the experiments to study any mass effects. While seated at a table, a participant moved a sphere over a small obstacle using their dominant hand. The participants were observed to move their wrist at a constant angular velocity. This phenomenon has not been reported previously. Theoretically, the muscles of the wrist provide an impulse of force at the start of the rotation while the forearm maintains a constant vertical force on a sphere. Light-heavy mean differences for the velocities, absolute velocities, angles and times taken showed no significant differences (p = 0.05).

Shoulder and elbow muscle activity during fully supported trajectory tracking in people who have had a stroke.

An inability to perform tasks involving reaching is a common problem for stroke patients. This paper provides an insight into mechanisms associated with recovery of upper limb function by examining how stroke participants' upper limb muscle activation patterns differ from those of neurologically intact participants, and how they change in response to an intervention. In this study, five chronic stroke participants undertook nine tracking tasks in which trajectory (orientation and length), speed and resistance to movement were varied. During these tasks, EMG signals were recorded from triceps, biceps, anterior deltoid, upper, middle and lower trapezius and pectoralis major. Data collection was performed in sessions both before, and after, an intervention in which participants performed a similar range of tracking tasks with the addition of responsive electrical stimulation applied to their triceps muscle. The intervention consisted of eighteen one hour treatment sessions, with two participants attending an additional seven sessions. During all sessions, each participant's arm was supported by a hinged arm-holder which constrained their hand to move in a two dimensional plane. Analysis of the pre intervention EMG data showed that timing and amplitude of peak EMG activity for all stroke participants differed from neurologically intact participants. Analysis of post intervention EMG data revealed that statistically significant changes in these quantities had occurred towards those of neurologically intact participants.

Feasibility of iterative learning control mediated by functional electrical stimulation for reaching after stroke.

BACKGROUND: An inability to perform tasks involving reaching is a common problem following stroke. Evidence supports the use of robotic therapy and functional electrical stimulation (FES) to reduce upper limb impairments, but current systems may not encourage maximal voluntary contribution from the participant because assistance is not responsive to performance. OBJECTIVE: This study aimed to investigate whether iterative learning control (ILC) mediated by FES is a feasible intervention in upper limb stroke rehabilitation. METHODS: Five hemiparetic participants with reduced upper limb function who were at least 6 months poststroke were recruited from the community. No participants withdrew. INTERVENTION: Participants undertook supported tracking tasks using 27 different trajectories augmented by responsive FES to their triceps brachii muscle, with their hand movement constrained in a 2-dimensional plane by a robot. Eighteen 1-hour treatment sessions were used with 2 participants receiving an additional 7 treatment sessions. OUTCOME MEASURES: The primary functional outcome measure was the Action Research Arm Test (ARAT). Impairment measures included the upper limb Fugl-Meyer Assessment (FMA), tests of motor control (tracking accuracy), and isometric force. RESULTS: Compliance was excellent and there were no adverse events. Statistically significant improvements were measured (P

A robotic workstation for stroke rehabilitation of the upper extremity using FES.

An experimental test facility is developed for use by stroke patients in order to improve sensory-motor function of their upper limb. Subjects are seated at the workstation and their task is to repeatedly follow reaching trajectories that are projected onto a target above their arm. To do this they use voluntary control with the addition of electrical stimulation mediated by advanced control schemes applied to muscles in their impaired shoulder and arm. Full details of the design of the workstation and its periphery systems are given, together with a description of its use during the treatment of stroke patients.

Shoulder and elbow muscle activity during fully supported trajectory tracking in neurologically intact older people.

An inability to perform tasks involving reaching is a common problem for stroke patients. Knowledge of normal muscle activation patterns during these tasks is essential to the identification of abnormal patterns in post-stroke hemiplegia. Findings will provide insight into changes in muscle activation patterns associated with recovery of upper limb function. In this study with neurologically intact participants the co-ordination of shoulder and elbow muscle activity during two dimensional reaching tasks is explored. Eight participants undertook nine tracking tasks in which trajectory (orientation and length), duration, speed and resistance to movement were varied. The participants' forearm was supported using a hinged arm-holder, which constrained their hand to move in a two dimensional plane. EMG signals were recorded from triceps, biceps, anterior deltoid, upper, middle and lower trapezius and pectoralis major. A wide variation in muscle activation patterns, in terms of timing and amplitude, was observed between participants performing the same task. EMG amplitude increased significantly with length, duration and resistance of the task for all muscles except anterior deltoid. Co-activation between biceps and triceps was significantly dependent on both task and trajectory orientation. Activation pattern of pectoralis major was dependent on trajectory. Neither trajectory orientation nor task condition affected the activation pattern of anterior deltoid. Normal ranges of timing of muscle activity during the tasks were identified.

Clinometric properties of a clinical spasticity measurement tool.

PURPOSE: To investigate clinometric properties of an Anglo-Dutch spasticity measurement tool (ADSMT), an objective tool providing information about both neurophysiological and biomechanical aspects of spasticity about the wrist joint in the clinical setting. METHOD: ADSMT measurements were performed with 12 healthy and 11 participants with post-stroke spasticity, and consisted of assessing the maximum range of passive wrist movement (pROM) and passive wrist extension at different cycle rates. Outcome measures were wrist angle, flexor and extensor activation, and resistance to movement. Intra-class Correlation Coefficients (ICCs) were calculated for inter-rater and test-retest reliability. Validity was investigated by calculating Spearman's rho between ADSMT outcome measures and the Modified Ashworth Scale (n=12), the Action Research Arm Test (n=6), and a validated wrist rig (n=6). RESULTS: Impaired participants had higher flexor activity and higher resistance to movement during passive wrist extension compared to unimpaired participants. For all outcome measures inter-rater and test-retest reliability were satisfactory to good and concurrent validity was sufficient. CONCLUSIONS: Outcome measures related to wrist flexor activity and resistance to movement during extension are promising for spasticity assessment using the ADSMT. Further knowledge on reference values and practicality is necessary for this tool to become incorporated in the clinical setting.

Analysis of the quality of wrist movement during a simple tracking task.

Objective assessment of stroke-patients' ability to control arm movements is vital for evidence-based therapy and progress monitoring. This study compares three different indices to quantify the quality of wrist movement during a task involving tracking a target on a screen. Each method is assessed in terms of agreement between assessors (Bland and Altman limits of agreement); repeatability of readings by the same assessor (reliability coefficient); and external validity on data collected from a sample of people with impaired upper limb function and an age matched unimpaired control group. The three indices were the root mean square difference between the wrist movement and the target signal, the cross correlation between these two signals, and an estimate of the signal-to-noise ratio in the wrist movement. External validity was investigated by calculating the correlation between each measure for wrist movement, and upper limb function assessed by the action research arm test. The results of the Bland and Altman limits of agreement show that all indices were similar in performance. The cross correlation had the highest reliability coefficient for the impaired group. In terms of external validity, the cross correlation and signal-to-noise indices showed the strongest association with functional performance and may thus be the more relevant for future clinical investigations.

Electrical muscle stimulation acutely mimics exercise in neurologically intact individuals but has limited clinical benefits in patients with type 2 diabetes.

BACKGROUND: Electrical muscle stimulation mimics exercise in individuals with neurological injury or disease and improves measures of fitness and glucose metabolism. Physical activity improves features of the metabolic syndrome in patients with type 2 diabetes but many patients find it difficult to exercise. AIMS: To determine whether use of an electrical muscle stimulator mimics exercise in neurologically intact individuals and has metabolic benefits in patients with type 2 diabetes. METHODS: Acute changes in pulse, blood pressure and energy expenditure were measured in 33 healthy volunteers using the muscle stimulator. Acute changes in glucose uptake were measured in five subjects with type 2 diabetes. Body composition, features of the metabolic syndrome and measures of insulin sensitivity were measured before and after 12 weeks daily use of the stimulator in four subjects with type 2 diabetes. RESULTS: The muscle stimulator acutely increased pulse, blood pressure, energy expenditure and glucose uptake. Daily use over 12 weeks improved insulin stimulated nonesterified fatty acid suppression but did not result in changes in body composition or clinical parameters. CONCLUSION: Although the muscle stimulator acutely mimics exercise, limitations in the size of the stimulating current mean that the magnitude of these changes is too small to produce clinical benefit.

Biomechanical approaches applied to the lower and upper limb for the measurement of spasticity: a systematic review of the literature.

PURPOSE: To review and characterise biomechanical approaches for the measurement of spasticity as one component of the upper motor neurone syndrome. METHOD: Systematic literature searches based on defined constructs and a four-step review process of approaches used or described to measure spasticity, its association with function or associated phenomena. Most approaches were limited to individual joints and therefore, to reflect this trend, references were grouped according to which body joint(s) were investigated or whether it addressed a functional activity. For each joint, references were further sub-divided into the types of measurement method described. RESULTS: A database of 335 references was established for the review process. The knee, ankle and elbow joints were the most popular, perhaps reflecting the assumption that they are mono-planar in movement and therefore simpler to assess. Seven measurement methods were identified: five involving passive movement (manual, controlled displacement, controlled torque, gravitational and tendon tap) and two involving active movement (voluntary and functional). Generally, the equipment described was in an experimental stage and there was a lack of information on system properties, such as accuracy or reliability. Patient testing was either by cohort or case studies. The review also conveyed the myriad of interpretations of the concept of spasticity. CONCLUSIONS: Though biomechanical approaches provide quantitative data, the review highlighted several limitations that have prevented them being established as an appropriate method for clinical application to measure spasticity.

Theoretical and methodological considerations in the measurement of spasticity.

PURPOSE: To discuss the measurement of spasticity in the clinical and research environments, make recommendations based on the SPASM reviews of biomechanical, neurophysiological and clinical methods of measuring spasticity and indicate future developments of measurement tools. METHOD: Using the results of the systematic reviews of the biomechanical, neurophysiological and clinical approaches, methods were evaluated across three dimensions: (1) validity, reliability and sensitivity to change; (2) practical quality such as ease of use and (3) qualities specific to the measurement of spasticity, for example ability to be applied to different muscle groups. Methods were considered in terms of applicability to research and clinical applications. RESULTS: A hierarchy of measurement approaches was identified from highly controlled and more objective (but unrelated to function) to ecologically valid, but less objective and subject to contamination from other variables. The lack of a precise definition of spasticity may account for the problem of developing a valid, reliable and sensitive method of measurement. The reviews have identified that some tests measure spasticity per se, some phenomena associated with spasticity or consequential to it and others the effect of spasticity on activity and participation and independence. CONCLUSIONS: Methods appropriate for use in research, particularly into the mechanism of spasticity did not satisfy the needs of the clinician and the need for an objective but clinically applicable tool was identified. A clinical assessment may need to generate more than one 'value' and should include evaluation of other components of the upper motor neurone syndrome. There is therefore a need for standardized protocols for 'best practice' in application of spasticity measurement tools and scales.

Effect of gait cycle selection on EMG analysis during walking in adults and children with gait pathology.

This paper presents the results of a project to evaluate different methods of gait cycle selection on the analysis of electromyography recorded during gait. Electromyography (EMG) describes the electrical activity associated with the muscle and is often interpreted in gait analysis using a simultaneously obtained signal to identify phases of the gait cycle. Phase transitions are often selected manually from reference signals derived from additional instrumentation, such as pressure platforms, footswitches and video cameras. We propose two methods (automatic and semi-automatic) as an alternative to the more traditional manual selection, and analyse how the gait cycle selection affects the EMG analysis. To quantify the differences between the gait cycles obtained using each method and to classify each cycle, three indices have been introduced. The effect of the gait cycle selection has been evaluated with respect to the EMG step profiles and temporal gait descriptors. An asymptomatic adult, an asymptomatic child and two children with cerebral palsy were examined using telemetric EMG devices and pressure footswitches. The results obtained showed that the method of gait cycle selection did not have a major influence for the adult, but it altered considerably the analysis in the case of the children with cerebral palsy.

Indices to describe different muscle activation patterns, identified during treadmill walking, in people with spastic drop-foot.

This study was concerned with individuals who were unable to effectively dorsiflex their ankle when walking, as a result of a lesion of the central nervous system (CNS). Indices that categorise and quantify different patterns of calf and anterior tibial muscle activation patterns during treadmill walking have been derived from a sample of fifteen individuals with established hemiplegia following stroke and twelve age-matched individuals without impairment. As subjects walked on a treadmill, force sensitive foot-switches under the heel and first metatarsal head allowed EMG signals from the calf and anterior tibial muscles to be related to phases of the gait cycle. Normal activation periods for each muscle group were identified as percentiles of the gait cycle and indices for muscle activation periods were derived using ratios of integrated EMG during selected periods. Indices were derived that identified statistically significant differences, between normal and hemiplegic subjects, in calf activation during both push-off phase (P<0.001) and early stance phase (P<001), but not activation of tibialis anterior during swing (P=0.325) Observation suggested that integrated tibialis anterior activity during swing phase in hemiplegic subjects was not dissimilar to normal subjects, but the profile in hemiplegic subjects tended to lack the normal second peak of activity at initial foot contact. The reasons for drop-foot were shown to be varied and complex. The indices defined may be useful for directing therapy and measuring outcome.

Does the drop-foot stimulator improve walking in hemiplegia?

This article presents an overview of the research and clinical experience of the use of Functional Electrical Stimulation (FES) for the treatment of drop-foot in hemiplegia. The article reviews the evidence from the literature over the past 10 years to answer the question posed in the title. A description and explanation of drop-foot stimulation is followed by a review and discussion of the literature based on a search of the databases Medline, Cinhal, and Embase from 1990 to 2000, using the key words: stimulation and hemiplegia and (common and peroneal) or (functional and electrical) and (walking or gait) and drop* foot). Nine papers were reviewed, only one of which was a randomized controlled trial. Quality of research is criticized and the need for rigorous clinical studies, technological development, and collaboration between clinicians and engineers is argued. The drop foot stimulator does improve walking in hemiplegia, but factors such as patient and clinician education, reliability of equipment, and selection of patients, are important.