The effects of foot position and orientation on inter- and intra-foot coordination in standing postures: a frequency domain PCA analysis

Active Videogame Training Combined with Conventional Therapy Alters Body Oscillation in Children with Cerebral Palsy: A Randomized Controlled Trial

Objective: Assess the effect of nonimmersive virtual reality (VR) training as complementary rehabilitation on body oscillation in children with cerebral palsy (CP) while standing on different bases of support and surfaces. Materials and Methods: Twenty-three children with unilateral CP randomly allocated to an intervention group (IG, n = 12) or control group (CG, n = 11). The IG underwent two weekly 50-minute sessions of VR training over 8 weeks, associated with conventional therapy, while the CG was submitted to two 45-minute sessions of conventional neurodevelopmental-based physiotherapy a week over the same time period. Participants were evaluated on a force platform under control conditions (CCs) (rigid surface, feet parallel); semitandem stance; flexible surface (FS) with feet parallel; and flexible surface in a semitandem (FSST) stance. The effect of the group and time factors on the center of pressure oscillation variables was analyzed by repeated-measures analysis of variance (ANOVA), with significance set at 0.05. Results: The main effect observed was for time on the FS, with a decline in the amplitude of mediolateral (ML Amp) (P = 0.01) and mediolateral root mean square (P = 0.01) after intervention. In the IG, ML Amp also declined after intervention under CCs (P = 0.02) and total velocity increased for FSST (P = 0.04). The percentage change was significant only in the IG. Conclusion: VR training as complementary rehabilitation can help improve body oscillation in children with CP and mild functional impairment. Nonimmersive VR can be considered a complementary tool for the physical rehabilitation of children with CP. This study was registered with the Brazilian Clinical Trials Registry (RBR-3zty4w).

Efficiency of Leg Exoskeleton Use in Rehabilitation of Cerebral Stroke Patients

The study aimed to evaluate the effectiveness of functional and motor activity restoration, including the walking function, in patients after an ischemic stroke using the ExoAtlet lower limb exoskeleton.

Patients and methods. A clinical study was carried out on 42 patients who had undergone a cerebral infarction in the mid cerebral artery system with a post-stroke paresis of the leg, and who had undergone a rehabilitation course in a round-theclock hospital during the early recovery period. Patients were randomized into two equal groups comparable in terms of the stroke severity: the patients in group 1 were receiving a standard rehabilitation program (control group), the patients in group 2 were additionally receiving a course of gait rehabilitation using the ExoAtlet exoskeleton - 10 sessions, 5 sessions per week for 14 days.

Results. The study demonstrated the effectiveness of the ExoAtlet exoskeleton used in the rehabilitation of stroke patients over the standard course of rehabilitation. The advantages include a decrease in the hemiparesis degree, an increase in the muscle strength of the paretic limb, an improvement in balance, an improvement and acceleration of the walking process. The obtained results of the instrumental study confirmed the benefits of physical training on the Exoskeleton, which was demonstrated through an increase in stability and balance, as well as through a decrease in the energy consumption index for maintaining the stable verticalization.

Conclusion. The usage of the ExoAtlet exoskeleton increases the effectiveness of rehabilitation measures and improves motor and functional activities of patients who have suffered a cerebral stroke.

Static postural sway of women with and without fibromyalgia syndrome: A cross-sectional study

BACKGROUND

There is a frequent complaint about balance problems among fibromyalgia syndrome patients; however, there are not enough studies that have shown static postural sway of women with fibromyalgia syndrome. This study aimed to compare static postural sway of women with and without fibromyalgia syndrome.

METHODS

This is a cross-sectional study in which twenty-nine women with fibromyalgia syndrome and 20 without took part. A posturography evaluation was performed in six different situations (bipedal, right tandem and left tandem, with eyes opened and closed), and questionnaires for clinical depression symptoms, clinical anxiety symptoms, sleep quality, and Visual Analogue Scales for Pain and Fatigue were applied. Mann-Whitney U test was used to check differences among groups; Wilcoxon matched-pair test was used to check differences intragroup; Cohen d coefficient was used to measure effect sizes and Pearson Correlation Coefficient was used for correlations among variables. Level of significance adopted was 5%.

FINDINGS

Women with fibromyalgia syndrome have presented worse postural sway than women without fibromyalgia syndrome in all situations (P<0.05), and worse scores in all questionnaires (P<0.05). In the eyes closed situations, women with fibromyalgia syndrome presented worse postural sway than women without in the same conditions.

INTERPRETATION

Women with fibromyalgia syndrome have worse performance in the static posture test, more prominent in reduced support bases with eyes closed. Pain, fatigue, depression and anxiety may have directly influenced postural sway in fibromyalgia syndrome patients.

iVAR: a program for imputing missing data in multivariate time series using vector autoregressive models

This article introduces iVAR, an R program for imputing missing data in multivariate time series on the basis of vector autoregressive (VAR) models. We conducted a simulation study to compare iVAR with three methods for handling missing data: listwise deletion, imputation with sample means and variances, and multiple imputation ignoring time dependency. The results showed that iVAR produces better estimates for the cross-lagged coefficients than do the other three methods. We demonstrate the use of iVAR with an empirical example of time series electrodermal activity data and discuss the advantages and limitations of the program.

Inter-foot coordination dynamics of quiet standing postures

It has long been held that the net center of pressure (COP(NET)) is the controlling variable to human stance that indirectly represents postural sway. The formation of the COP(NET) trajectory emerges from an active control of transporting the body weight from one foot to the other and the self-organized coordination of the COP of each individual foot—properties that cannot be determined from the typical single force platform protocol. The findings of recent studies, with the application of the two-force platform paradigm, have revealed the coordination properties of the lower limbs in regulating COP(NET). In this article, we review these new findings and insights into the control of postural stability within the framework of a dynamic systems approach. The issues include: (1) the active asymmetrical body weight distribution and transportation process during both short- and long-term stances; (2) the spatial and temporal characteristics of the inter- and intra-foot COP coupling dynamics; (3) the influence of mechanical constraints (e.g., foot position, foot orientation, etc.) on the inter-foot and intra-foot COP coordination dynamics; and (4) the role of the specificity of task context to the functional asymmetry of the feet and its relation to footedness. The findings from foot coordination dynamics reveal subtle regulation of stability and instability in postural control that needs to be mapped to the coordination dynamics of the multi-link postural control system.

Thalamic metabolic alterations with cognitive dysfunction in idiopathic trigeminal neuralgia: a multivoxel spectroscopy study

INTRODUCTION

Although abnormalities in metabolite compositions in the thalamus are well described in patients with idiopathic trigeminal neuralgia (ITN), differences in distinct thalamic subregions have not been measured with proton magnetic resonance spectroscopy ((1)H-MRS), and whether there are correlations between thalamic metabolites and cognitive function still remain unknown.

METHODS

Multivoxel MRS was recorded to investigate the metabolic alterations in the thalamic subregions of patients with ITN. The regions of interest were localized in the anterior thalamus (A-Th), intralaminar portion of the thalamus (IL-Th), posterior lateral thalamus (PL-Th), posterior medial thalamus (PM-Th), and medial and lateral pulvinar of the thalamus (PuM-Th and PuL-Th). The N-acetylaspartate to creatine (NAA/Cr) and choline to creatine (Cho/Cr) ratios were measured in the ITN and control groups. Scores of the visual analogue scale (VAS) and the Montreal Cognitive Assessment (MoCA) were analyzed to correlate with the neuroradiological findings.

RESULTS

The NAA/Cr ratio in the affected side of PM-Th and PL-Th in ITN patients was statistically lower than that in the corresponding regions of the thalamus in controls. The NAA/Cr ratio in the affected PM-Th was negatively associated with VAS and disease duration. Furthermore, decreases of NAA/Cr and Cho/Cr were detected in the affected side of IL-Th, and lower Cho/Cr was positively correlated with MoCA values in the ITN group.

CONCLUSIONS

Our result of low level of NAA/Cr in the affected PM-Th probably serves as a marker of the pain-rating index, and decreased Cho/Cr in IL-Th may be an indicator of cognitive disorder in patients with ITN.