Dynamic Stability, Symmetry, and Smoothness of Gait in People with Neurological Health Conditions.

Neurological disorders such as stroke, Parkinson's disease (PD), and severe traumatic brain injury (sTBI) are leading global causes of disability and mortality. This study aimed to assess the ability to walk of patients with sTBI, stroke, and PD, identifying the differences in dynamic postural stability, symmetry, and smoothness during various dynamic motor tasks. Sixty people with neurological disorders and 20 healthy participants were recruited. Inertial measurement unit (IMU) sensors were employed to measure spatiotemporal parameters and gait quality indices during different motor tasks. The Mini-BESTest, Berg Balance Scale, and Dynamic Gait Index Scoring were also used to evaluate balance and gait. People with stroke exhibited the most compromised biomechanical patterns, with lower walking speed, increased stride duration, and decreased stride frequency. They also showed higher upper body instability and greater variability in gait stability indices, as well as less gait symmetry and smoothness. PD and sTBI patients displayed significantly different temporal parameters and differences in stability parameters only at the pelvis level and in the smoothness index during both linear and curved paths. This study provides a biomechanical characterization of dynamic stability, symmetry, and smoothness in people with stroke, sTBI, and PD using an IMU-based ecological assessment.

Sham-controlled randomized multicentre trial of transcranial direct current stimulation for prolonged disorders of consciousness.

BACKGROUND AND PURPOSE: Transcranial direct current stimulation (tDCS) has been shown to improve signs of consciousness in a subset of patients with disorders of consciousness (DoC). However, no multicentre study confirmed its efficacy when applied during rehabilitation. In this randomized controlled double-blind study, the effects of tDCS whilst patients were in rehabilitation were tested at the group level and according to their diagnosis and aetiology to better target DoC patients who might repond to tDCS. METHODS: Patients received 2 mA tDCS or sham applied over the left prefrontal cortex for 4 weeks. Behavioural assessments were performed weekly and up to 3 months' follow-up. Analyses were conducted at the group and subgroup levels based on the diagnosis (minimally conscious state [MCS] and unresponsive wakefulness syndrome) and the aetiology (traumatic or non-traumatic). Interim analyses were planned to continue or stop the trial. RESULTS: The trial was stopped for futility when 62 patients from 10 centres were enrolled (44 ± 14 years, 37 ± 24.5 weeks post-injury, 18 women, 32 MCS, 39 non-traumatic). Whilst, at the group level, no treatment effect was found, the subgroup analyses at 3 months' follow-up revealed a significant improvement for patients in MCS and with traumatic aetiology. CONCLUSIONS: Transcranial direct current stimulation during rehabilitation does not seem to enhance patients' recovery. However, diagnosis and aetiology appear to be important factors leading to a response to the treatment. These findings bring novel insights into possible cortical plasticity changes in DoC patients given these differential results according to the subgroups of patients.

Rehabilitation outcomes in Huntington disease patients with low body mass index.

OBJECTIVES: A catabolic state and a progressive body weight loss are a well-documented hallmark of Huntington Disease (HD). No study is still available on the effectiveness of intensive in-hospital rehabilitation in HD patients with low body mass index (BMI). METHODS: Twenty HD patients with low BMI value were enrolled in this study. Disease severity was assessed before and after rehabilitation by the Barthel Index, the Total Functional Capacity Scale, and the Physical Performance Test. RESULTS: BMI-scores correlated with clinical measures before and after rehabilitation. All patients showed an improvement in outcome measures (p<0.001), and an increase in BMI values (p<0.001) after rehabilitation. Effectiveness of rehabilitation correlated with the values of BMI assessed before reheducational programs (p=0.024) and with BMI values observed in each patient in the three months before admission to hospital (p=0.002). CONCLUSIONS: Findings of the current study show that the effectiveness of the rehabilitation is positively correlated with the BMI values and confirm the efficacy of in-hospital intensive rehabilitation as a valid strategy finalized to improve neuromotor performances and global functional recovery even in HD patients with low BMI and at risk of malnutrition.

Artificial Neural Network Detects Hip Muscle Forces as Determinant for Harmonic Walking in People after Stroke.

Many recent studies have highlighted that the harmony of physiological walking is based on a specific proportion between the durations of the phases of the gait cycle. When this proportion is close to the so-called golden ratio (about 1.618), the gait cycle assumes an autosimilar fractal structure. In stroke patients this harmony is altered, but it is unclear which factor is associated with the ratios between gait phases because these relationships are probably not linear. We used an artificial neural network to determine the weights associable to each factor for determining the ratio between gait phases and hence the harmony of walking. As expected, the gait ratio obtained as the ratio between stride duration and stance duration was found to be associated with walking speed and stride length, but also with hip muscle forces. These muscles could be important for exploiting the recovery of energy typical of the pendular mechanism of walking. Our study also highlighted that the results of an artificial neural network should be associated with a reliability analysis, being a non-deterministic approach. A good level of reliability was found for the findings of our study.

Validation of SuPerSense, a Sensorized Surface for the Evaluation of Posture Perception in Supine Position.

This study aimed to validate a sensorized version of a perceptive surface that may be used for the early assessment of misperception of body midline representation in subjects with right stroke, even when they are not yet able to stand in an upright posture. This device, called SuPerSense, allows testing of the load distribution of the body weight on the back in a supine position. The device was tested in 15 patients with stroke, 15 age-matched healthy subjects, and 15 young healthy adults, assessing three parameters analogous to those conventionally extracted by a baropodometric platform in a standing posture. Subjects were hence tested on SuPerSense in a supine position and on a baropodometric platform in an upright posture in two different conditions: with open eyes and with closed eyes. Significant correlations were found between the lengths of the center of pressure path with the two devices in the open-eyes condition (R = 0.44, p = 0.002). The parameters extracted by SuPerSense were significantly different among groups only when patients were divided into those with right versus left brain damage. This last result is conceivably related to the role of the right hemisphere of the brain in the analysis of spatial information.

Efficacy of Vestibular Rehabilitation in Patients With Neurologic Disorders: A Systematic Review.

OBJECTIVE: The aim of this systematic review is to critically assess the effectiveness of vestibular rehabilitation (VR) administered either alone or in combination with other neurorehabilitation strategies in patients with neurologic disorders. DATA SOURCES: An electronic search was conducted by 2 independent reviewers in the following databases: MEDLINE (PubMed), the Physiotherapy Evidence Database, and the Cochrane Database of Systematic Reviews. STUDY SELECTION: All clinical studies carried out on adult patients with a diagnosis of neurologic disorders who performed VR provided alone or in combination with other therapies were included. DATA EXTRACTION: Screening of titles, abstracts, and full texts and data extraction were undertaken independently by pairs of reviewers. Included studies were quality appraised using a modified version of the Newcastle-Ottawa Scale. DATA SYNTHESIS: The summary of results was reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Twelve studies were included in the review. All the included studies, with 1 exception, report that improvements provided by customized VR in subject affected by a central nervous system diseases are greater than traditional rehabilitation programs alone. CONCLUSIONS: Because of the lack of high-quality studies and heterogeneity of treatments protocols, clinical practice recommendations on the efficacy of VR cannot be made. Results show that VR programs are safe and could easily be implemented with standard neurorehabilitation protocols in patients affected by neurologic disorders. Hence, more high-quality randomized controlled trials of VR in patients with neurologic disorders are needed.

Effect of dual-task training on balance in patients with multiple sclerosis: A systematic review and meta-analysis.

OBJECTIVE: To evaluate the effects of dual-task training on static and dynamic balance in patients with multiple sclerosis. DATA SOURCES: PubMed/MEDLINE, EMBASE, Scopus, and PEDro databases were searched from inception to March 1, 2021. METHODS: This study was conducted in agreement with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Two reviewers assessed studies for inclusion and extracted data. We used the Physiotherapy Evidence Database scale to evaluate the methodological quality and the risk-of-bias. Randomized clinical trial data were pooled for the meta-analysis. The effect sizes and 95% confidence interval (CI) were calculated by random-effect models. Egger regression and Begg-Mazumdar rank correlation test were used for publication bias. RESULTS: A total of 13 studies involving 584 patients (42.3 ± 9 years mean ± SD; 377 females) met the inclusion criteria for the systematic review, while nine were included in the meta-analysis. People who received dual-task training interventions showed significant improvements in the Timed Up & Go test 0.44 [(95% CI = 0.22; 0.65), P-value<0.001], and in the Berg Balance scale 0.46 [(95% CI = 0.07; 0.85), P-value = 0.02]. Low and moderate heterogeneity between the studies was found for the Timed Up & Go test and the Berg Balance scale, respectively. CONCLUSION: The findings from the current meta-analysis support dual-task training as a beneficial therapy for improving dynamic balance and functional mobility in patients with multiple sclerosis. The limited number of studies that investigated static balance performance after dual-task training do not currently allow us to draw a conclusion about any possible improvements in this ability.

The Promotoer, a brain-computer interface-assisted intervention to promote upper limb functional motor recovery after stroke: a study protocol for a randomized controlled trial to test early and long-term efficacy and to identify determinants of response.

BACKGROUND: Stroke is a leading cause of long-term disability. Cost-effective post-stroke rehabilitation programs for upper limb are critically needed. Brain-Computer Interfaces (BCIs) which enable the modulation of Electroencephalography (EEG) sensorimotor rhythms are promising tools to promote post-stroke recovery of upper limb motor function. The "Promotoer" study intends to boost the application of the EEG-based BCIs in clinical practice providing evidence for a short/long-term efficacy in enhancing post-stroke hand functional motor recovery and quantifiable indices of the participants response to a BCI-based intervention. To these aims, a longitudinal study will be performed in which subacute stroke participants will undergo a hand motor imagery (MI) training assisted by the Promotoer system, an EEG-based BCI system fully compliant with rehabilitation requirements. METHODS: This longitudinal 2-arm randomized controlled superiority trial will include 48 first ever, unilateral, subacute stroke participants, randomly assigned to 2 intervention groups: the BCI-assisted hand MI training and a hand MI training not supported by BCI. Both interventions are delivered (3 weekly session; 6 weeks) as add-on regimen to standard intensive rehabilitation. A multidimensional assessment will be performed at: randomization/pre-intervention, 48 h post-intervention, and at 1, 3 and 6 month/s after end of intervention. Primary outcome measure is the Fugl-Meyer Assessment (FMA, upper extremity) at 48 h post-intervention. Secondary outcome measures include: the upper extremity FMA at follow-up, the Modified Ashworth Scale, the Numeric Rating Scale for pain, the Action Research Arm Test, the National Institute of Health Stroke Scale, the Manual Muscle Test, all collected at the different timepoints as well as neurophysiological and neuroimaging measures. DISCUSSION: We expect the BCI-based rewarding of hand MI practice to promote long-lasting retention of the early induced improvement in hand motor outcome and also, this clinical improvement to be sustained by a long-lasting neuroplasticity changes harnessed by the BCI-based intervention. Furthermore, the longitudinal multidimensional assessment will address the selection of those stroke participants who best benefit of a BCI-assisted therapy, consistently advancing the transfer of BCIs to a best clinical practice. TRIAL REGISTRATION: Name of registry: BCI-assisted MI Intervention in Subacute Stroke (Promotoer). TRIAL REGISTRATION NUMBER: NCT04353297 ; registration date on the ClinicalTrial.gov platform: April, 15/2020.

Clinical features of fallers among inpatient subacute stroke: an observational cohort study.

BACKGROUND AND PURPOSE: The aim of this study is to observe the differences between fallers, common fallers, and non-fallers in stroke patients compared with the global ability in a rehabilitation setting. MATERIALS AND METHODS: An observational and prospective study has been carried out. A total of 476 subacute stroke patients have been observed. The main outcome measures were assessed using the Canadian Neurological Scale (CNS), Barthel Index (BI), Functional Ambulatory Category (FAC), and Trunk Control Test (TCT) at admission to the rehabilitation unit and after 90 days of the rehabilitation treatment (nearly 3 h for day for 5 days for week) at the discharge with intermediate evaluations after the first and second months. RESULTS: Out of 397 patients, 109 reported 1 or more falls (27.5%), of whom 67 fell 1 time (fallers) in the hospital (16.9%) and 42 fell 2 or more times (common fallers) (10.6%). For fallers, BI and FAC scores had a significant effect (p = 0.003 for both). Common fallers had statistically significant differences in BI (p = 0.002), FAC (p = 0.012), and TCT scores (0.023) compared with non-fallers. CONCLUSIONS: The severity of stroke may directly increase the risk of fall, and also indirectly, lengthening the hospitalization. Our study seems to suggest that patients with BI scores of between 21 and 30 on admission are more prone to fall in the first period of hospitalization, whereas in the second month, those with scores of between 11 and 20 on admission have a higher risk of falls. In the third month, patients with BI scores below 10 on admission are more susceptible to falls.

Exercise treatment effect modifiers in persistent low back pain: an individual participant data meta-analysis of 3514 participants from 27 randomised controlled trials.

BACKGROUND: Low back pain is one of the leading causes of disability worldwide. Exercise therapy is widely recommended to treat persistent non-specific low back pain. While evidence suggests exercise is, on average, moderately effective, there remains uncertainty about which individuals might benefit the most from exercise. METHODS: In parallel with a Cochrane review update, we requested individual participant data (IPD) from high-quality randomised clinical trials of adults with our two primary outcomes of interest, pain and functional limitations, and calculated global recovery. We compiled a master data set including baseline participant characteristics, exercise and comparison characteristics, and outcomes at short-term, moderate-term and long-term follow-up. We conducted descriptive analyses and one-stage IPD meta-analysis using multilevel mixed-effects regression of the overall treatment effect and prespecified potential treatment effect modifiers. RESULTS: We received IPD for 27 trials (3514 participants). For studies included in this analysis, compared with no treatment/usual care, exercise therapy on average reduced pain (mean effect/100 (95% CI) -10.7 (-14.1 to -7.4)), a result compatible with a clinically important 20% smallest worthwhile effect. Exercise therapy reduced functional limitations with a clinically important 23% improvement (mean effect/100 (95% CI) -10.2 (-13.2 to -7.3)) at short-term follow-up. Not having heavy physical demands at work and medication use for low back pain were potential treatment effect modifiers-these were associated with superior exercise outcomes relative to non-exercise comparisons. Lower body mass index was also associated with better outcomes in exercise compared with no treatment/usual care. This study was limited by inconsistent availability and measurement of participant characteristics. CONCLUSIONS: This study provides potentially useful information to help treat patients and design future studies of exercise interventions that are better matched to specific subgroups. PROTOCOL PUBLICATION: https://doi.org/10.1186/2046-4053-1-64.

Sensorized Assessment of Dynamic Locomotor Imagery in People with Stroke and Healthy Subjects.

Dynamic motor imagery (dMI) is a motor imagery task associated with movements partially mimicking those mentally represented. As well as conventional motor imagery, dMI has been typically assessed by mental chronometry tasks. In this paper, an instrumented approach was proposed for quantifying the correspondence between upper and lower limb oscillatory movements performed on the spot during the dMI of walking vs. during actual walking. Magneto-inertial measurement units were used to measure limb swinging in three different groups: young adults, older adults and stroke patients. Participants were tested in four experimental conditions: (i) simple limb swinging; (ii) limb swinging while imagining to walk (dMI-task); (iii) mental chronometry task, without any movement (pure MI); (iv) actual level walking at comfortable speed. Limb swinging was characterized in terms of the angular velocity, frequency of oscillations and sinusoidal waveform. The dMI was effective at reproducing upper limb oscillations more similar to those occurring during walking for all the three groups, but some exceptions occurred for lower limbs. This finding could be related to the sensory feedback, stretch reflexes and ground reaction forces occurring for lower limbs and not for upper limbs during walking. In conclusion, the instrumented approach through wearable motion devices adds significant information to the current dMI approach, further supporting their applications in neurorehabilitation for monitoring imagery training protocols in patients with stroke.

Neuropsychological disorders in non-central nervous system cancer: a review of objective cognitive impairment, depression, and related rehabilitation options.

AIM: The objective of the present review was to systematically characterize the types of cognitive impairment that are found in different non-brain types of cancer as measured by objective and validated tests, and also to further examine depression and cognitive function in cancer patients and explore their available rehabilitation treatments. RESULTS: A total of 29 articles were reviewed. Most of these studies suggest that chemotherapy as well as the combination of chemotherapy and hormonal therapy can influence cognition in different types of cancer patients. Breast cancer patients appear to be the most affected in neuropsychological function, specifically in terms of cognitive impairment and reduced quality of life, as compared to other non-brain solid tumours. Overall, the most impaired functions were verbal ability, memory, executive function, and motor speed. CONCLUSION: Chemotherapy-related cognitive dysfunction remains under-recognized and undertreated. The various studies reported differing and non-homogenous findings with mixed results, obtained by self-reporting and web-assisted assessment, with other confounding factors such as age and depression during both cancer diagnosis and treatment. An objective neuropsychological assessment is fundamental to avoid underestimation of the extent of chemobrain. Self-reported and web-assisted assessment may ultimately result in confusion between the neuropsychological signs of chemobrain versus those of depression.

Bilateral upper limb rehabilitation with videogame-based feedback in corticobasal degeneration: a case reports study.

Corticobasal degeneration (CBD) is a neurodegenerative disorder characterized by a combination of cortical and basal ganglia signs. We reported two cases treated with a bilateral upper limb rehabilitation tool with videogame based feedback for 3 time per week for 8 weeks. Both patients showed an improvement of pinch and grasp forces and motor function. However, both of them reported an increased upper limb pain. Bilateral upper limb mechanical device with exergame feedback was effective also in the two patients suffering of CBD for limiting the effects of apraxia by performing intensive purposeful task training.

Romberg ratio coefficient in quiet stance and postural control in Parkinson's disease.

The aim of this study was to determine the function of visual afference in postural control in Parkinson patients. We enrolled 29 patients and 30 healthy controls. The stabilometry test was performed for posture and balance and Romberg ratio coefficients were calculated. In addition, the Berg Balance Scale and the 6-Minute Walking Test were administered to assess balance and functional exercise capacity; the Unified Parkinson's Disease Rating Scale was used to determine the stage of the disease; and the Short Form (SF)-36 Health Survey was given to collect information on quality of life. RESULTS: significantly longer Center of Pressure (CoP) sway lengths were observed in the parkinson group. The Romberg index for CoP length of sway in parkinson patients was 94.3 ± 19.3%, versus 147.4 ± 120.6% for the control group. (p = 0.025). CONCLUSION: Parkinson patients use the increase in CoP sway length and ellipse area to stabilize their balance and sight does not facilitate static postural control as in healthy subjects.

Does robot-assisted gait training improve ambulation in highly disabled multiple sclerosis people? A pilot randomized control trial.

BACKGROUND: Robotic training is commonly used to assist walking training in patients affected by multiple sclerosis (MS) with non-conclusive results. OBJECTIVE: To compare the effect of robot-assisted gait training (RAGT) with that of conventional walking training (CWT) on gait competencies, global ability, fatigue and spasticity in a group of severely affected patients with MS. METHODS: A pilot, single-blind randomized controlled trial was conducted in 43 severe (Expanded Disability Status Scale (EDSS) score of 6-7.5) and non-autonomous ambulant in-patients with MS. Experimental group performed 12 sessions of RAGT, whereas control group performed the same amount of CWT. Primary outcome measures were gait ability assessed by 2 minutes walking test and Functional Ambulatory Category; secondary outcomes were global ability (modified Barthel Index), global mobility (Rivermead Mobility Index), severity of disease (EDSS) and subjectively perceived fatigue (Fatigue Severity Scale). RESULTS: The number of subjects who achieved a clinical significant improvement was significantly higher in RAGT than in CWT ( p < 0.05 for both primary outcome measures). RAGT also led to an improvement in all the other clinical parameters (global ability: p < 0.001, global mobility: p < 0.001, EDSS: p = 0.014 and fatigue: p = 0.001). CONCLUSIONS: RAGT improved the walking competencies in non-autonomous ambulant patients with MS, with benefits in terms of perceived fatigue.

Brain-computer interface boosts motor imagery practice during stroke recovery.

OBJECTIVE: Motor imagery (MI) is assumed to enhance poststroke motor recovery, yet its benefits are debatable. Brain-computer interfaces (BCIs) can provide instantaneous and quantitative measure of cerebral functions modulated by MI. The efficacy of BCI-monitored MI practice as add-on intervention to usual rehabilitation care was evaluated in a randomized controlled pilot study in subacute stroke patients. METHODS: Twenty-eight hospitalized subacute stroke patients with severe motor deficits were randomized into 2 intervention groups: 1-month BCI-supported MI training (BCI group, n = 14) and 1-month MI training without BCI support (control group; n = 14). Functional and neurophysiological assessments were performed before and after the interventions, including evaluation of the upper limbs by Fugl-Meyer Assessment (FMA; primary outcome measure) and analysis of oscillatory activity and connectivity at rest, based on high-density electroencephalographic (EEG) recordings. RESULTS: Better functional outcome was observed in the BCI group, including a significantly higher probability of achieving a clinically relevant increase in the FMA score (p < 0.03). Post-BCI training changes in EEG sensorimotor power spectra (ie, stronger desynchronization in the alpha and beta bands) occurred with greater involvement of the ipsilesional hemisphere in response to MI of the paralyzed trained hand. Also, FMA improvements (effectiveness of FMA) correlated with the changes (ie, post-training increase) at rest in ipsilesional intrahemispheric connectivity in the same bands (p < 0.05). INTERPRETATION: The introduction of BCI technology in assisting MI practice demonstrates the rehabilitative potential of MI, contributing to significantly better motor functional outcomes in subacute stroke patients with severe motor impairments.

Wii Fit is effective in women with bone loss condition associated with balance disorders: a randomized controlled trial.

The use of exergame for balance competencies was recently explored in women affected by balance ability reduction with non-conclusive results. The aim of the study was to evaluate the efficacy of a supervised exergame performed with the Wii Fit® compared to conventional exercises on balance function, quality of life, fear of fall and well-being in women with bone loss. Thirty-eight female participants aged over 65 years, with a bone loss condition, were enrolled and random allocated in the Wii group or control group. Subject enrolled in Wii group performed a balance training with a Wii Fit supervised by a physiotherapist (1 h, 2 days per week, during 8 weeks) while in control subjects performed the same amount of conventional balance exercises. Subject enrolled in experimental group showed significantly higher scores in terms of Berg Balance Scale (p = 0.027). In SF-36 scores, a significant difference was reported for physical activity score after treatment (p = 0.031). Fear of falling and the psychological scales were not significantly different between the two groups. In women with bone loss condition, a supervised Wii Fit training has shown better efficacy in improving balance performance with respect to conventional balance exercises.

Overground walking training with the i-Walker, a robotic servo-assistive device, enhances balance in patients with subacute stroke: a randomized controlled trial.

BACKGROUND: Patients affected by mild stroke benefit more from physiological overground walking training than walking-like training performed in place using specific devices. The aim of the study was to evaluate the effects of overground robotic walking training performed with the servo-assistive robotic rollator (i-Walker) on walking, balance, gait stability and falls in a community setting in patients with mild subacute stroke. METHODS: Forty-four patients were randomly assigned to two different groups that received the same therapy in two daily 40-min sessions 5 days a week for 4 weeks. Twenty sessions of standard therapy were performed by both groups. In the other 20 sessions the subjects enrolled in the i-Walker-Group (iWG) performed with the i-Walker and the Control-Group patients (CG) performed the same amount of conventional walking oriented therapy. Clinical and instrumented gait assessments were made pre- and post-treatment. The follow-up observation consisted of recording the number of fallers in the community setting after 6 months. RESULTS: Treatment effectiveness was higher in the iWG group in terms of balance improvement (Tinetti: 68.4 ± 27.6 % vs. 48.1 ± 33.9 %, p = 0.033) and 10-m and 6-min timed walking tests (significant interaction between group and time: F(1,40) = 14.252, p = 0.001; and F(1,40) = 7.883, p = 0.008, respectively). When measured, latero-lateral upper body accelerations were reduced in iWG (F = 4.727, p = 0.036), suggesting increased gait stability, which was supported by a reduced number of falls at home. CONCLUSIONS: A robotic servo-assisted i-Walker improved walking performance and balance in patients affected by mild/moderate stroke, leading to increased gait stability and reduced falls in the community. TRIAL REGISTRATION: This study was registered on anzctr.org.au (July 1, 2015; ACTRN12615000681550 ).

The Three Laws of Neurorobotics: A Review on What Neurorehabilitation Robots Should Do for Patients and Clinicians.

Most studies and reviews on robots for neurorehabilitation focus on their effectiveness. These studies often report inconsistent results. This and many other reasons limit the credit given to these robots by therapists and patients. Further, neurorehabilitation is often still based on therapists' expertise, with competition among different schools of thought, generating substantial uncertainty about what exactly a neurorehabilitation robot should do. Little attention has been given to ethics. This review adopts a new approach, inspired by Asimov's three laws of robotics and based on the most recent studies in neurorobotics, for proposing new guidelines for designing and using robots for neurorehabilitation. We propose three laws of neurorobotics based on the ethical need for safe and effective robots, the redefinition of their role as therapist helpers, and the need for clear and transparent human-machine interfaces. These laws may allow engineers and clinicians to work closely together on a new generation of neurorobots.

Stability and Harmony of Gait in Patients with Subacute Stroke.

Stroke affects many gait features, such as gait stability, symmetry, and harmony. However, it is still unclear which of these features are directly altered by primary damage, and which are affected by the reduced walking speed. The aim of this study was to analyze the above gait features in patients with subacute stroke with respect to the values observed in age- and speed-matched healthy subjects. A wearable triaxial accelerometer and an optoelectronic device were used for assessing the upright gait stability, symmetry of trunk movements, and harmonic structure of gait phases by means of the root-mean-square (RMS) acceleration of the trunk, harmonic ratio (HR), and gait ratios (GRs), respectively. For healthy subjects, results showed that RMS acceleration increased with speed, HR peaked at a comfortable speed, and GRs tended towards the theoretical value of the golden ratio for speeds >1 m/s. At matched speed conditions, patients showed higher instabilities in the latero-lateral axis (p = 0.001) and reduced symmetry of trunk movements (p = 0.002). Different from healthy subjects, antero-posterior and latero-lateral acceleration harmonics were coupled in patients (R = 0.507, p = 0.023). Conversely, GRs were not more altered in patients than in slow-walking healthy subjects. In conclusion, patients with stroke showed some characteristics similar to those of the elderly when the latter subjects walk slowly, and some altered characteristics, such as increased latero-lateral instabilities coupled with movements performed along the antero-posterior axis.