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International audience; Background and objective In a proof-of-concept study, we aimed to verify whether the wearable haptic anklets, a device that delivers personalized suprathreshold alternating exteroceptive stimulation at the anklets on demand, may improve the quality of walking, including the freezing of gate (FOG), in idiopathic Parkinson's disease (PD) patients. The clinical relevance of the presented device as a walking pacemaker to compensate the disturbed locomotion through the generation of a more physiological internal walking rhythm should be verified in a dedicated clinical trial. Methods We tested 15 patients diagnosed as idiopathic PD, during their regular treatment regimen. Patients were evaluated during walking with the device switched on and off, personalized at their most comfortable cadence. Stride velocity, variance, and length, as well as FOG episode duration during walking or turning of 180°, were quantified by an optical high-performance motion capture VICON system. Results The alternating, rhythmic, sensory stimulation significantly improved either walking velocity or reduced inter-stride variance. Effects were more variable on stride length. The significant reduction of FOG episodes' duration correlated with clinical severity of scales rating gate and balance. No safety problems occurred. Conclusions The WEARHAP-PD device, whose Technology Readiness Level (TRL) is 6, significantly improved some walking abilities (walking velocity and stride variance) and reduced the duration of FOG episodes in idiopathic PD patients. Unlike the traditional auditory and visual explicit cues that require the user's allocation of attention for correct functioning, the interaction of the patients with the surrounding environment was preserved, due to the likely implicit processing of haptic stimuli.

Electrophysiology plays a crucial role in Guillain-Barré syndrome (GBS) diagnosis and subtype classification. The aim of our study was to assess the potential role of distal compound muscle action potential (dCMAP) for early differentiation between acute inflammatory demyelinating polyneuropathy (AIDP) and axonal GBS.We retrospectively reviewed the medical records of 24 subjects with AIDP and 18 subjects with axonal GBS. We built up receiver operating characteristic curves for total dCMAP duration and negative phase of dCMAP duration, in order to derive cut-off values able to differentiate between AIDP and axonal GBS.The total duration of dCMAP was significantly prolonged in AIDP compared to axonal GBS. AUCs, odds ratio and positive predictive values were higher for total duration than for negative peak duration. Nerve conduction parameters in the lower limbs were more sensitive than those in the upper limbs in distinguishing AIDP from axonal GBS.Total duration of dCMAP dispersion may capture an adjunctive component of distal demyelination, not measured by the more traditional parameters and may thus represent a useful tool for early differentiation between AIDP and axonal GBS.

Background Prospective study to investigate the effects of elastic stockings (GCS) 23-32 mmHg at ankle on Hoffmann reflex (H-reflex) from soleus muscle under rest and after a walking program. Methods Fourteen subjects wore two types of GCS, at different times. Electrophysiological examinations were carried out at rest without and with GCS, immediately after walking with GCS and 20 minutes later after removing GCS. Results Peripheral nerve conduction remained unchanged after using the GCS. Conversely, walking with GCS led to changes in a spinal cord pathway expressed as a decrease of H-threshold and an increase of H-size as a function of stimulus intensity, which lasted for at least 20 minutes. Conclusions GCS has no effect on the peripheral nervous system. The GCS intolerance and the discomfort sometimes reported by patients do not derive from a dysfunction of the lower limb peripheral nervous system. A positive action on spinal reflex excitability is detected after walking while wearing GCS. We suggest that nervous descending activity due to voluntary contractions, and afferent cutaneous discharge, enhanced by movement under compression, converge on inhibitory interneurons, thus impinging on presynaptic pathways. All this can lead to an enhancement of the monosynaptic responses. Higher limb oxygenation detected during walking with GCS, found by other Authors, could increase the sensitivity of the muscle spindle afferents and/or motor neuron excitability resulting in an increase in H-reflex excitability, with potential positive effects on neuromuscular activities improving proprioception and postural control of the lower limbs.

Introduction In this study we collected reference values for the across-tarsal-tunnel conduction of the motor tibial nerve (mTN). Methods The mTN compound muscle action potentials (CMAPs) from the abductor hallucis muscle were obtained by stimulating below/above the malleolus and the popliteal fossa. The effect of weight, height, body mass index (BMI), foot and leg length, sex, and age were evaluated using univariate and multivariate correlation analyses, and predictive equations for each mTN conduction parameter were developed. Results On the basis of data from 185 subjects, there were differences between women and men in all anthropometric parameters and for some nerve conduction values. Through multivariate analysis, age, but not sex, was found to have a significant impact. Height affected both distal and proximal conduction velocity. BMI affected CMAP amplitude. Discussion mTN conduction is influenced by various demographic and anthropometric factors. For all intrinsic factors, height demonstrated the greatest effect on mTN conduction across the tarsal tunnel.

Considerable debate exists in the literature about possible anomalies of ulnar nerve at wrist in carpal tunnel syndrome (CTS). We systematically reviewed the literature about electrophysiologic and morphologic changes of ulnar nerve at wrist in CTS. We carried out a comprehensive search using PubMed from 1963 through October 2017. Data were extracted and the quality of the included studies was evaluated. Twenty-eight studies were selected. Seventy-nine percent of the studies report abnormalities of the ulnar nerve conduction. There was a relation between the median and ulnar nerve conduction in almost all the papers, i.e., conduction impairment of the ulnar nerve increased with increasing severity of median nerve involvement, emerging as a process correlated with damage of the median nerve. Seventy-five percent of ultrasonographic studies report changes of ulnar nerve cross sectional area in CTS. Morphologic and functional changes of the ulnar nerve and/or Guyon canal are reported by 100% of papers addressed to this topic. Several papers quoted in this review have some flaws. The key message of present review is that electrophysiological and morphological changes of the ulnar nerve at the wrist can occur in CTS, although the possibility of an overestimation of the phenomenon needs to be considered.

For the management of Parkinson's disease (PD), the concept of forced exercise (FE) has drawn interest. In PD subjects, the FE executed with lower limbs has been shown to lessen symptoms and to promote brain adaptive changes. Our study is aimed to investigate the effect of an upper-limb exercise, conceptually comparable with the FE, in PD. Upper-limb exercise was achieved in a sitting position by using a specially designed device (Angel's Wings®). Clinical data, computerized dynamic posturography, magnetic resonance imaging (MRI) (resting-state MRI and arterial spin labeling), and neuropsychological tests were used before and after 2 months' exercise training. We found a significant long-lasting improvement in Unified Parkinson Disease Rating Scale (UPDRS)-III and cognitive scales, along with improvement in balance and postural control (better alignment of the gravity center and improvement in weight symmetry and in anticipatory motor strategies). Computerized dynamic posturography pointed out an enhanced central ability to integrate the vestibular signals with afferents from other sensory systems. Neuroimaging analyses after 2 months' exercise training showed, with respect to pretraining condition, many changes. An increase of the cerebral blood flow was evident in the left primary motor cortex (M1), left supplementary motor cortical area, and left cerebellar cortex. The bilateral globus pallidus showed an increased functional connectivity to the right central operculum, right posterior cingulate gyrus, and left sensorimotor cortex. Seed-to-voxel analysis demonstrated a functional connectivity between M1 and the left superior frontal gyrus. Left crus II showed strengthened connections with the left pre-rolandic area, left post-rolandic area, and left supramarginal area. These findings likely reflect compensatory mechanisms to the neuropathological hallmark of PD. Overall, our results show that this upper-limb exercise model, conceptually comparable with the FE already tested in the lower limbs, leads to a global improvement (involving non-exercised limbs) likely consistent with the functional changes observed in the central nervous system.

Most of the cerebral functions are asymmetrically represented in the two hemispheres. Moreover, dexterity and coordination of the distal segment of the dominant limbs depend on cortico-motor lateralization. In this study, we investigated whether postural control may be also considered a lateralized hemispheric brain function. To this aim, 15 young subjects were tested in standing position by measuring center of pressure (COP) shifts along the anteroposterior axis (COP-Y) during dynamic posturography before and after continuous Theta Burst Stimulation (cTBS) intervention applied to the dominant or non-dominant M1 hand area as well as to the vertex. We show that when subjects were expecting a forward platform translation, the COP-Y was positioned significantly backward or forward after dominant or non-dominant M1 stimulation, respectively. We postulate that cTBS applied on M1 may have disrupted the functional connectivity between intra- and interhemispheric areas implicated in the anticipatory control of postural stability. This study suggests a functional asymmetry between the two homologous primary motor areas, with the dominant hemisphere playing a critical role in the selection of the appropriate postural control strategy.

Background Postural instability may result from altered sequencing of automatic motor programs for anticipatory postural corrections and/or impaired motor learning in Parkinson Disease (PD) patients. Comorbid white matter disease is a major determinant of axial motor impairment, leading to poorer stability than nigrostriatal dopaminergic denervation per se. Objective To assess differences in anticipatory control of postural stability function between subjects affected by PD with comorbid leukoaraiosis (LPD), idiopathic Parkinson disease (IPD) and elderly healthy subjects (EHS) as control group. Methods Eight patients with IPD, eight patients with LPD and eight age/weight matched elderly healthy subjects (EHS) were tested in standing position by measuring the Center of Pressure (CoP) along the anteroposterior axis (CoP-Y) while subjects were expecting three repeated backward surface translation. Results LPD patients positioned the CoP-Y significantly backward while waiting for the second and third platform translations, with respect to their COP-Y position in preparation for the first translation. The IPD and EHS showed no significant differences in the COP-Y position among the repeated perturbation trials. Conclusions LPD patients show inability to rescale an effective preparatory postural pattern to known, repeated postural perturbations suggesting impaired sensory-motor strategies in anticipating perturbations. Anticipatory postural patterns remain effective in IPD patients.

This research studied, 25 adult patients who underwent physical therapy to assess the analgesic effect of distraction with the use of music during physical therapy. Patients randomly underwent physical therapy once with music provided by an iPod and once without music. In both sessions patients underwent identical physical procedures. At end of both sessions patients filled in 5-item questionnaire where they scored pain and other parameters, such as stress, enjoyment, interaction, and satisfaction, on 10-cm visual analog scale. The mean scores (range, 0-10) of the two sessions were statistically compared. Mean pain scores were significantly lower (p = .031) during the session in which patients received music (4.8 ± 2.5) than during the session without music (5.8 ± 2.3). The other items of the questionnaire did not disclose any statistically significant difference when the sessions with versus without music were compared. Enjoyment (8.5 ± 1.6), interaction (8.3 ± 1.9), and satisfaction (8.6 ± 1.7) scores with music did not significantly differ in the sessions without music (8.5 ± 2.1, 8.5 ± 1.9, and, 8.5 ± 1.5, respectively); mean stress score was, 3.9 in both sessions. The conclusion of the study is that music provided through a portable media player has an analgesic effect. This can be an effective analgesic strategy during painful physical therapy.

BACKGROUND AND PURPOSE: There is a need for individuating those post-stroke patients who may benefit from an optimal and customised rehabilitation plan aiming at early reintegration in community life participation. This study investigated whether the gain of independence in complex Activities of Daily Living (ADL) may be predicted before the discharge from the stroke unit using simple bedside determinants. METHODS: In 104 first-ever stroke patients with no previous disability, ten determinants at 10 days after stroke were selected. Multivariable logistic regression analysis was applied to identify the prognostic determinants able to predict independence in complex ADL, as measured by modified Rankin Scale grade ≤2. RESULTS: The model shows that having a Barthel Index ≥9, a Motricity Index- Upper Limb ≥75, an age ≤70 and being a male resulted in 100% probability of achieving independence in complex ADL. If three of the four determinants were present, the probability was more than 90%. With the presence of two of the four determinants, the probability ranged from 87% to 28%. With the presence of only one determinant, the probability was 13%. CONCLUSIONS: Accurate prediction of independence in complex ADL can be made before the discharge from the stroke unit. The strength of the paretic upper limb, age, gender, and the ability of performing basic ADL are the significant variables. The probability of favorable prognosis depends on the presence and on the robustness of each single determinant.

In this paper, we present the combination of the Soft-SixthFinger, a wearable robotic extra-finger designed to be used by chronic stroke patients to compensate for the missing hand function, with a robotic arm that is used as an assistive device to support the patient arm. The extra-finger is a tendon-driven modular structure worn at the paretic forearm. The robotic extra-finger is used jointly with the paretic hand/arm to grasp an object similarly to the two parts of a robotic gripper. The flexion/extension of the robotic finger is controlled by the patient using an Electromyography (EMG) interface embedded in a cap. The robotic arm is controlled to partially compensate for the weight of the paretic arm, while not interfering with the user arm motion. The system has been designed as a tool that can be used by chronic stroke patients to compensate for grasping in many Activities of Daily Living (ADL). We performed a pilot test to demonstrate that the proposed system can significantly improve the performance and the autonomy in ADL.

Myasthenia gravis (MG) is an autoimmune neuromuscular disorder in which disabling muscle weakness may affect health-related quality of life (HRQoL). The aim of this study was to investigate which common motor-functional deficits and corresponding severity are most determinant of poor HRQoL in these patients. In 41 patients, the dichotomized first item of the Italian Myasthenia Gravis Questionnaire (IMGQ), categorizing patients who report “good” and “poor” HRQoL, was chosen as dependent-outcome variable. All items composing the myasthenia gravis-specific scale (MG-ADL), i.e. talking, chewing, swallowing, breathing, impairment of ability to brush teeth or comb hair, impairment of ability to rise from chair, double vision, and eyelid droop were acquired as independent variables and dichotomized. Stepwise backward LR multivariable logistic regression analysis was performed. In addition, the main characteristics of patients were compared. MG-ADL items “chewing” ≥1, i.e. “fatigue chewing solid food”, and “breathing” ≥2, i.e. “shortness of breath at rest” proved to be significant determinants. Higher dose of corticosteroid therapy was significantly (p = 0.027; r s = −0.35), correlated with poor HRQoL. At diagnosis, a decremental response to repetitive nerve stimulation (RNS) from the abductor pollicis brevis was significantly more frequent in patients with poor HRQoL. In conclusion, impaired “chewing” and “breathing” functions indicate the need for careful planning of rehabilitation, re-education and patient management. Moreover, decremental response to RNS at diagnosis may identify patients at risk for poor HRQoL.

This paper presents a wearable robotic extra finger used by chronic stroke patients to compensate for the missing hand functions of the paretic limb. The extra finger is worn on the paretic forearm by means of an elastic band, and it is coupled with a vibrotactile ring interface worn on the healthy hand. The robotic finger and the paretic hand act like the two parts of a gripper working together to hold an object. The human user is able to control the flexion/extension of the robotic finger through a switch placed on the ring, while being provided with vibrotactile feedback about the forces exerted by the robotic finger on the environment. To understand how to control the vibrotactile interface to evoke the most effective cutaneous sensations, we carried out perceptual experiments to evaluate its absolute and differential thresholds. Finally, we performed a qualitative experiment, the Franchay Arm Test, with a chronic post-stroke patient presenting a partial loss of sensitivity on the paretic limb. Results show that the proposed system significantly improves the performance of the considered test.

While polarity-specific after-effects of monopolar transcranial direct current stimulation (tDCS) on cortico-spinal excitability are well-documented, modulation of vital parameters due to current spread through the brainstem is still a matter of debate, raising potential concerns about its use through the general public, as well as for neurorehabilitation purposes. We monitored online and after-effects of monopolar tDCS (primary motor cortex) in ten healthy subjects by adopting a neuronavigated transcranial magnetic stimulation (TMS)/tDCS combined protocol. Motor evoked potentials (MEPs) together with vital parameters (e.g. blood pressure, heart-rate variability and sympathovagal balance) were recorded and monitored before, during and after anodal, cathodal or sham tDCS. Ten MEPs every 2.5-minute time windows were recorded from the right First Dorsal Interosseus (FDI), while 5-minute epochs were used to record vital parameters. The protocol included 15 minutes of pre-tDCS and of online-tDCS, (anodal, cathodal or sham). After effects were recorded for 30 minutes. We showed a polarity-independent stabilization of cortical excitability level, a polarity-specific after-effects for cathodal and anodal stimulation, and an absence of persistent excitability changes during online stimulation. No significant effects on vital parameters emerged both during and after tDCS, while a linear increase in systolic/diastolic blood pressure and heart-rate variability was observed during each tDCS condition, as a possible unspecific response to experimental demands. Taken together, current findings provide new insights on the safety of monopolar tDCS, promoting its application both in research and clinical settings.

Background Individual factors in multiple sclerosis (MS) patients may modify the reliability of health-related quality of life (HRQOL) assessment. Knowledge of these effects may enable physicians to identify patients at risk for poor perceived health. Objective To investigate what individual factors may interact with MS symptoms and their severity to modify the reliability of HRQOL assessment; to explore the predictive values of the significant variables identified. Methods HRQOL was assessed in 57 patients by the 36-Item Short Form Health Survey (SF-36). The Physical Component Summary and Mental Component Summary were dichotomized and applied as dependent variables for logistic regression analysis. The Functional Independence Measure (FIM), Expanded Disability Status Scale (EDSS), Fatigue Severity Scale (FSS), Cognitive Behavioral Assessment (CBA) and specific individual factors were tested as independent variables. Two-way contingency tables were used to calculate the predictive values. Results Unemployment, smoking, and night waking were the most significant individual factors. Introversion, physical pain and difficulty falling asleep were also significant. EDSS-total ≥ 2, EDSS-pyramidal ≥ 2, FIM ≤ 123, FSS ≥ 5, depressive manifestations and bowel/bladder dysfunction were significant MS-related determinants. Sensitivity and specificity differed widely for each variable. Conclusions Individual factors have relevance in HRQOL assessment. Their identification may help physicians construct the patient's risk profile. Sensitivity and specificity add weight to the significance of variables.

BACKGROUND: Botulinum neurotoxin A (BoNT-A) may reduce lower limb spasticity but its role in improving walking ability remains to be established. OBJECTIVE: To investigate the efficacy of simultaneous BoNT-A injections into several targeted spastic muscles of different joints on gait speed and on functional gains in gait performance in chronic stroke and MS patients. METHODS: Twenty patients affected by stroke or multiple sclerosis were tested before, one and three months after BoNTA administration. Gait was evaluated by the 10 Meter Walk Test; patients were stratified into functional ambulation classes accordingly. Spasticity was assessed using the modified Ashworth Scale. RESULTS: At final assessment, spasticity was reduced in hip adductors and ankle plantar-flexors, gait speed improved and, 1/3rd of patients transitioned to a higher ambulation class. The pre-post difference in Level of Spasticity of the hips was a predictor for an increase in gait speed. CONCLUSIONS: A meaningful improvement in walking performance can be obtained in chronic spastic patients after BoNT-A injection into several muscles, specifically the hip adductors.

We aimed at investigating rapid effects of plasma cortisol elevations on the episodic memory phase of encoding or retrieval, and on the strength of the memory trace. Participants were asked either to select a word containing the letter "e" (shallow encoding task) or to judge if a word referred to a living entity (deep encoding task). We intravenously administered a bolus of 20mg of cortisol either 5 min before encoding or 5 min before retrieval, in a between-subjects design. The study included only male participants tested in the late afternoon, and neutral words as stimuli. When cortisol administration occurred prior to retrieval, a main effect of group emerged. Recognition accuracy was higher for individuals who received cortisol compared to placebo. The higher discrimination accuracy for the cortisol group was significant for words encoded during deep but not shallow task. Cortisol administration before encoding did not affect subsequent retrieval performance (either for deep or shallow stimuli) despite a facilitatory trend. Because genomic mechanisms take some time to develop, such a mechanism cannot apply to our findings where the memory task was performed shortly after the enhancement of glucocorticoid levels. Therefore, glucocorticoids, through non-genomic fast effects, determine an enhancement in episodic memory if administered immediately prior to retrieval. This effect is more evident if the memory trace is laid down through deep encoding operations involving the recruitment of specific neural networks.

OBJECTIVE: The modified Rankin Scale (mRS) and the Barthel Index (BI) are the most common clinimetrical instruments for measuring disability after stroke. This study investigated the relationship between the BI and the mRS at multiple time points after stroke. The BI, which is a widely used instrument for longitudinal follow-up post-stroke, was used as reference to determine the effect of time on the sensitivity of the mRS in differentiating functional recovery. METHODS: Ninety-two patients with first stroke and hemispheric brain lesion were evaluated using the BI and mRS at 10 days, 3 and 6 months. The Kruskal-Wallis test was applied to examine median differences in BI among the mRS levels at 10 days, 3 and 6 months with Dunn's correction for multigroup comparison. The Mann and Whitney test was used to compare median differences in BI scores between two aggregations of mRS grades (mRS=0-2, mRS=3-5) at the same time periods after stroke. RESULTS: BI score distribution amongst mRS grades overlapped at 10 days, differentiating only between extreme grades (no disability vs severe disability). At 3 months, independent patients with slight disability could be distinguished from dependent patients with marked disability. At 6 months, grade 2 and 3 overlapped no more, differentiating independence (class 0-2) from dependence (class 3-5). The largest transition to an independent functional status occurred from grade 4, at 3 months. CONCLUSION: Maximum sensitivity of mRS in differentiating functional recovery is reached at six months post-stroke.

A novel solution to compensate hand grasping abilities is proposed for chronic stroke patients. The goal is to provide the patients with a wearable robotic extra-finger that can be worn on the paretic forearm by means of an elastic band. The proposed prototype, the Robotic Sixth Finger, is a modular articulated device that can adapt its structure to the grasped object shape. The extra-finger and the paretic hand act like the two parts of a gripper cooperatively holding an object. We evaluated the feasibility of the approach with four chronic stroke patients performing a qualitative test, the Frenchay Arm Test. In this proof of concept study, the use of the Robotic Sixth Finger has increased the total score of the patients by two points in a five points scale. The subjects were able to perform the two grasping tasks included in the test that were not possible without the robotic extra-finger. Adding a robotic opposing finger is a very promising approach that can significantly improve the functional compensation of the chronic stroke patient during everyday life activities.