How Posture and Previous Sensorimotor Experience Influence Muscle Activity during Gait Imagery in Young Healthy Individuals.

This study explores how gait imagery (GI) influences lower-limb muscle activity with respect to posture and previous walking experience. We utilized surface electromyography (sEMG) in 36 healthy young individuals aged 24 (±1.1) years to identify muscle activity during a non-gait imagery task (non-GI), as well as GI tasks before (GI-1) and after the execution of walking (GI-2), with assessments performed in both sitting and standing postures. The sEMG was recorded on both lower limbs on the tibialis anterior (TA) and on the gastrocnemius medialis (GM) for all tested tasks. As a result, a significant muscle activity decrease was found in the right TA for GI-1 compared to GI-2 in both sitting (p = 0.008) and standing (p = 0.01) positions. In the left TA, the activity decreased in the sitting posture during non-GI (p = 0.004) and GI-1 (p = 0.009) in comparison to GI-2. No differences were found for GM. The subjective level of imagination difficulty improved for GI-2 in comparison to GI-1 in both postures (p < 0.001). Previous sensorimotor experience with real gait execution and sitting posture potentiate TA activity decrease during GI. These findings contribute to the understanding of neural mechanisms beyond GI.

Effect of Virtual Reality Therapy on Quality of Life and Self-Sufficiency in Post-Stroke Patients.

Background and Objectives: The consequences of stroke have a significant impact on self-sufficiency and health-related quality of life (HRQoL). Virtual reality (VR)-based rehabilitation has the potential to impact these modalities, but information on timing, volume, and intensity is not yet available. The aim of this randomized controlled trial (1:1) was to evaluate the impact of conventional rehabilitation combined with VR on self-care and domains of HRQoL in patients ≤6 months post-stroke. Materials and Methods: The intervention group completed a total of 270 min of conventional VR + rehabilitation sessions. The control group underwent conventional rehabilitation only. Primary assessments with the WHO disability assessment schedule 2.0 (WHODAS 2) questionnaire were conducted before rehabilitation (T0), after completion of the intervention (T1), and at the 4-week follow-up (T2); secondary outcomes included self-sufficiency and balance assessments. Results: Fifty patients completed the study (mean age 61.2 ± 9.0 years, time since stroke 114.3 ± 39.4 days). There were no statistically significant differences between the groups in WHODAS 2, self-sufficiency, and balance scores (p > 0.05). Conclusions: In the experimental group, there was a statistically significant difference in WHODAS 2, assessment of self-sufficiency, and balance scores before and after therapy (p < 0.05). VR appears to be a suitable tool to supplement and modify rehabilitation in patients after stroke.

Comparison of spatiotemporal gait parameters and their variability in typically developing children aged 2, 3, and 6 years.

Independent walking is an important milestone in a child's development. The maturation of central nervous system, changes in body proportions, spatiotemporal parameters of gait and their variability change are dependent on age. The first aim of this study was to compare non-normalized and normalized spatiotemporal parameters and their variability in children. The second aim was to determine which spatiotemporal parameters are most affected by aging. Data from 64 typically developing children (age: 2.0-6.9 years), who walked at a self-selected speed along a 10m walkway, were collected with a motion capture system. Spatiotemporal parameters were normalized based on leg length. The main effect of the non-normalized walking speed revealed a moderate effect size (ES = 0.72) comparing 2- and 3-years-old, a large effect size comparing 2- and 6-years-old (ES = 1.77), and a large ES comparing 3- and 6-years-old (ES = 1.22). The normalized stride width parameter showed a statistically significant difference with large effect size between 2 vs 3 (ES = 1.00), 2 vs 6 (ES = 3.17), and 3 vs 6 (ES = 1.96). A statistically significant decrease in intra-individual gait variability with increasing age was observed in all parameters except for stride width. The variability of stride width may serve as a parameter in 2-year-olds to assess deviations from typically developing children. The assessment of effect size could be a useful indicator for clinical practice.

Steady, Aim, Fire! Optimized Instructions Enhance Performance and Reduce Intra-Trial Variability in a Shooting Task.

The present study examined the influence of the individual and sequential combination of the key components of OPTIMAL (Optimizing Performance Through Intrinsic Motivation and Attention for Learning) theory (i.e., enhanced expectancies, autonomy support, and external focus), on the performance of a laser-pistol shooting task. In addition to shooting accuracy, intra-trial variability in the sway of forearm/pistol motion prior to movement execution (pulling the trigger) was the primary variable of interest. In a between-within-subject design, thirty-six participants (Mage = 21.27 ± 1.75 years) were randomized into either a control or an optimized group. Enhanced expectancies, autonomy support, and an external focus were implemented via sequential blocks of trials for participants in the optimized group. Participants in the control group performed all trials under "neutral" conditions. Our results showed that motor performance was enhanced for participants in the optimized group compared to those in the control group. Moreover, greater reductions in forearm sway leading up to the trigger pull were observed for the optimized group compared to the control group. These findings suggest higher movement effectiveness and efficiency, potentially through better attunement to task and environmental constraints, when implementing optimized instructions in a self-initiated fine motor task.

Review of ankle rehabilitation devices for treatment of equinus contracture.

INTRODUCTION: Equinus contracture is a serious disability and attention should be paid to proper and effective treatment. Most attention is given to neurologically impaired patients, but the incidence of equinus contracture is much higher, for example, in post-traumatic patients. In addition to conventional physical therapy, robotic rehabilitation treatment is one of the promising procedures to precede severe contraction cases and the need for surgery. AREAS COVERED: This study aims to cover the description of different types of stationary and wearable ankle rehabilitation devices suitable for the treatment of equinus contracture and point to deficiency in research, clinical trials, and launch of the market. EXPERT OPINION: This review provides insight into ankle rehabilitation devices with a focus on equinus contracture. Due to the fact that robotic devices successfully restore the condition of patients, attention should not be paid only to those with neurological impairments. This paper points that future research should be effectively linked to clinical practice with the aim of covering a wider range of disabilities and make an effort to successfully introduce devices from development into the practice.

Do different multi-segment foot models detect the same changes in kinematics when wearing foot orthoses?

BACKGROUND: Different multi-segment foot models have been used to explore the effect of foot orthoses. Previous studies have compared the kinematic output of different multi-segment foot models, however, no study has explored if different multi-segment foot models detect similar kinematic changes when wearing a foot orthoses. The aim of this study was to compare the ability of two different multi-segment foot models to detect kinematic changes at the hindfoot and forefoot during the single and double support phases of gait when wearing a foot orthosis. METHODS: Foot kinematics were collected during walking from a sample of 32 individuals with and without a foot orthosis with a medial heel bar using an eight-camera motion capture system. The Oxford Foot Model (OFM) and a multi-segment foot model using the Calibrated Anatomical System Technique (CAST) were applied simultaneously. Vector field statistical analysis was used to explore the kinematic effects of a medial heel bar using the two models, and the ability of the models to detect any changes in kinematics was compared. RESULTS: For the hindfoot, both models showed very good agreement of the effect of the foot orthosis across all three anatomical planes during the single and double support phases. However, for the forefoot, the level of agreement between the models varied with both models showing good agreement of the effect in the coronal plane but poorer agreement in the transverse and sagittal planes. CONCLUSIONS: This study showed that while consistency exists across both models for the hindfoot and forefoot in the coronal plane, the forefoot in the transverse and sagittal planes showed inconsistent responses to the foot orthoses. This should be considered when interpreting the efficacy of different interventions which aim to change foot biomechanics.

Influence of Rehabilitation Aid with Biofeedback on the Rehabilitation Process during Remote Home-Based Rehabilitation.

Ensuring the regularity and correctness of rehabilitation exercises in the home environment is a prerequisite for successful treatment. This clinical study compares balance therapy in the home environment on a conventional balance mat and an instrumented wobble board, with biofeedback supported by a rehabilitation scheme realized as web-based software that controls the course of rehabilitation remotely. The study included 55 patients with knee injuries. The control group consisted of 25 patients (12 females and 13 males, mean age 39 ± 12 years) and the study group of 30 patients (19 females and 11 males, mean age 40 ± 12 years). Treatment effects were compared using the ICS Balance Platform measurement system. Measurements showed significant differences in the change in ICS Balance platform parameters representing the dynamic stability of the patients. The dynamic stability improved more with the instrumented wobble board. The study did not show an influence of different methods of communication with patients during home-based rehabilitation.

Recent Trends, Construction, and Applications of Smart Textiles and Clothing for Monitoring of Health Activity: A Comprehensive Multidisciplinary Review.

In the area of biomedical signal monitoring, wearable electronics represents a dynamically growing field with a significant impact on the market of commercial products of biomedical signal monitoring and acquisition, as well as consumer electronic for vital functions monitoring. Since the electrodes are perceived as one of the most important part of the biomedical signal monitoring, they have been one of the most frequent subjects in the research community. Electronic textile (e-textile), also called smart textile represents a modern trend in the wearable electronics, integrating of functional materials with common clothing with the goal to realize the devices, which include sensors, antennas, energy harvesters and advanced textiles for self-cooling and heating. The area of textile electrodes and e-textile is perceived as a multidisciplinary field, integrating material engineering, chemistry, and biomedical engineering. In this review, we provide a comprehensive view on this area. This multidisciplinary review integrates the e-textile characteristics, materials and manufacturing of the textile electrodes, noise influence on the e-textiles performance, and mainly applications of the textile electrodes for biomedical signal monitoring and acquisition, including pressure sensors, electrocardiography, electromyography, electroencephalography and electrooculography monitoring.

Evaluation of the Usability of the Tiger Full-Foot Three-Dimensional Scanner for the Measurements of Basic Foot Dimensions in Clinical Practice.

BACKGROUND: Foot dimension information is important both for footwear design and clinical applications. In recent years, noncontact three-dimensional (3-D) foot digitizers/scanners have become popular because they are noninvasive and are valid and reliable for most of the measures. Some of them also offer automated calculations of basic foot dimensions. We aimed to determine test-retest reliability, objectivity, and concurrent validity of the Tiger full-foot 3-D scanner and the relationship between manual measures of the medial longitudinal arch of the foot and alternative parameters obtained automatically by the scanner. METHODS: Intraclass correlation coefficients and minimal detectable change values were used to assess the reliability and objectivity of the scanner. Concurrent validity and the relationships between the arch height measures were determined by the Pearson correlation coefficient and the limits of agreement between the scanner and the caliper method. RESULTS: The relative and absolute agreement between the repeated measurements obtained by the scanner show excellent reliability and objectivity of linear measures and only good to nearly good test-retest reliability and objectivity of arch height. Correlations between the values obtained by the scanner and the caliper were generally higher in linear measures (rp ≥ 0.929). The representativeness of state of bony architecture by the soft-tissue margin of the medial foot arch demonstrates the lowest correlation among the measurements (rp ≤ 0.526). CONCLUSIONS: The Tiger full-foot 3-D scanner offers excellent reliability and objectivity in linear measures, which correspond to those obtained by the caliper method. However, values obtained by both methods should not be used interchangeably. The arch height measure is less accurate, which could limit its use in some clinical applications. Orthotists and related professions probably appreciate the scanner more than other specialists.

Postural Control Strategies and Balance-Related Factors in Individuals with Traumatic Transtibial Amputations.

Mechanisms behind compromised balance control in people with transtibial amputation need to be further explored, as currently little is known specifically about postural control strategies in people with traumatic transtibial amputation (tTTA). The aim of this study is to assess automatic and voluntary postural control strategies in individuals with unilateral tTTA compared to those in control subjects and to define the effect of balance-related factors on these strategies. Automatic posture reactions and volitional motion toward given direction using standardized posturographic protocols (NeuroCom) of the Motor Control Test (MCT) and Limits of Stability (LOS) were assessed in eighteen participants with tTTA and eighteen age-matched controls. Compared to the controls, the participants with tTTA bore less weight on the prosthetic leg (p < 0.001) during the MCT and had reduced inclination toward the prosthetic leg (p < 0.001) within the LOS. In the tTTA group, the weight-bearing symmetry and the inclination toward the prosthetic leg (p < 0.05) was positively correlated with prosthesis use duration (p < 0.05). The current study indicates that decreased utilization of the prosthetic leg in tTTAs represents adaptive postural control strategy, but as prosthesis use duration increased, the engagement of the prosthetic leg improved.

The immediate effects of sensorimotor foot orthoses on foot kinematics in healthy adults.

BACKGROUND: Sensorimotor foot orthoses is an alternative concept, which in addition to mechanical effects, are designed to change muscle activation by altering sensory input to the plantar surface of the foot. However, there is little evidence of how these affect the kinematics of the foot during gait. RESEARCH QUESTION: The aim of the study was to explore the immediate effect of calcaneal medial heel bars and retrocapital bars on foot kinematics during the stance phase of gait. METHODS: Kinematic data were collected from 32 healthy individuals using an eight camera motion capture system and a six-degrees-of-freedom multi-segment foot model in three different orthotic conditions; calcaneal medial heel bar, retrocapital bar, and no orthosis. Vector field statistical analysis was performed to explore the effect of the orthotic conditions over the kinematic time series curves during stance phase. Peak median and interquartile ranges were also reported during the different phases of stance. RESULTS: The calcaneal medial bar significantly decreased rearfoot eversion for the majority of the stance phase and compensatory increased midfoot eversion during the entire stance phase compared to the no orthosis condition. The retrocapital bar rotated the foot externally significantly abducting the rearfoot for the entire stance phase and the midfoot for the majority of stance phase. SIGNIFICANCE: The calcaneal medial heel bar and retrocapital bar significantly altered the foot kinematics in a way that may benefit patients with abnormal pronation and intoeing gait.

Evaluation of Postural Stability Differences in the Elderly Through Recurrent Analysis.

Measuring the center of pressure (CoP) for a subject positioned on a force plate is one of the most commonly used tools to investigate balance. Several studies have proven a significant degradation of the body's stability after the age of 60. The conclusions, however, are based on a limited number of indicators and without systematic nonlinear analysis methods being used to evaluate the progression of CoP parameter values. Neither the change in CoP movement in subjects over 60 years of age nor the considerations of their body mass index (BMI) has been systematically evaluated by nonlinear methods so far. This study is based on one of the frequent methods for nonlinear evaluation - the Recurrent Quantification analysis. This article discusses the applicability of this method with regards to the evaluation of changes in postural stability of subjects over 60 years of age. Postural stability changes were evaluated using CoP motion and tested by the nonlinear method. For this research purpose, a group of 103 elderly women were selected and divided into age-respective groups of 60-69 years and 70-79 years old. Each age group was further divided into a subgroup of normal and overweight subjects according to their BMI. The following recurrent analysis parameters were employed in the evaluation of CoP motion in medial-lateral and anterior-posterior directions: determinism (DET), laminarity (LAM) and trapping time (TT). The results of the Wilcoxon test revealed a statistically significant difference between the values in parameters for the different age groups of overweight subjects almost in all the cases. Conversely, statistically significant differences between age groups rarely occurred in a subgroup of subjects with a normal BMI.

Postural stability after treadmill and overground walking in young and elderly.

BACKGROUND: Ageing commonly disrupts the balance control and compensatory postural responses that contribute to maintaining balance and preventing falls during perturbation of posture. Improvement of compensatory postural responses during walking is one of the main goals in fall prevention programs which often include treadmill walking training. However, during treadmill walking, there is a sensory (visualsomatosensory and vestibular-somatosensory) conflict that can evoke aftereffects of self-motion sensation and could alter postural stability after training. RESEARCH QUESTION: The aim of this study was to compare the effect of overground and treadmill walking on postural stability in healthy young and elderly subjects. METHODS: Postural responses of 31 Young and 19 healthy Elderly before and after overground and treadmill walking were assessed by a force platform in four stance conditions: firm and foam surface with eyes open and eyes closed. RESULTS: In Elderly group, velocity parameters significantly increased after treadmill walking but not after overground walking. This increase was found particularly in the conditions with eyes open in both types of surfaces (firm, foam). The velocity parameters values (expect Vx) were significantly increased in Elderly compared to Young almost in all four conditions after treadmill and overground walking. SIGNIFICANCE: Our study suggests that Elderly become more unstable after treadmill walking and have greater difficulties to adapt to new balance circumstances caused by sensory conflict associated with treadmill walking. It seems that during treadmill walking and subsequent stance, vision is the major factor contributing to posture stabilization. Thus, the suitability of treadmill walking as a part of training programs for elderly adults with higher fall risk should be seriously considered.

Immediate effect of individual bars of insoles and their combination on gait parameters in asymptomatic healthy adults.

Objective: The way how individual bars of sensorimotor insoles influence the gait kinematics is not fully understood yet. Therefore, this study aimed to explore the effect of three sensorimotor orthotic conditions (the medial calcaneal and retrocapital lateral bars and their combination) on the gait parameters in healthy adults during the stance phase of gait cycle.Materials and methods: Twenty-six young adults performed 20 gait cycles in each condition using their self-selected cadence and provided standardised shoes with the base-sole and the three types of orthotics. A three-dimensional motion analysis system (8 cameras; 200 Hz) was used and a six-degrees of freedom model was applied. The cadence, the stride length, the first peaks of foot external rotation, eversion and dorsal flexion as well as the first peak of hip adduction were analysed.Results: Significant differences (p < 0.05) were found for all parameters between the orthotic conditions, except the cadence. Significant difference in the first peak of hip adduction (p = 0.008) was found between the dominant and non-dominant leg. There were no significant interactions between the factors of condition and leg dominance (p > 0.05).Conclusions: There seems to be overall tendencies in immediate changes in ankle joint kinematics caused by all three sensorimotor orthotic conditions and besides the mechanical principles, also 'proprioceptive mechanism' seems to play a role. However, maximum observed average angular change was 2° and some variability in reactions to each orthotic condition exists among the individuals. Therefore, clinical relevance of such changes remains unclear and careful analysis of expected outcomes should be the common part of every orthotic intervention.

The Effects of Attentional Focus Instruction on the Performance of a Whole-Body Coordination Task in Children With Developmental Coordination Disorder.

BACKGROUND AND AIM: Previous studies have supported the advantages of an external focus of attention (EFA) relative to an internal focus of attention (IFA) in healthly adults. However, effects of attentional focus instructions on skill performance and acquisition in children are equivocal. The aim of this study was to examine the effects of attentional focus instructions on performance of a whole body coordination task in children with and without developmental coordination disorder (DCD). METHODS: Children with DCD (n = 18) and typically developing (TD) children (n = 21) (9-10 years) were asked to perform 3 countermovement vertical jumps in the IFA (Concentrate on the swing of your arms), EFA (Concentrate on getting as close to the ceiling as possible), and control conditions. RESULTS: The results showed that regardless of children's motor development proficiency, the jump height and vertical take-off velocity (VTO) were higher in EFA relative to both IFA and Con conditions. In addition, VTO was significantly higher in the Con relative to IFA condition. CONCLUSION: The results of the current study showed that EFA relative to IFA instructions could enhance the neuromuscular activation of dynamic contractions of the leg muscles in both children with and without DCD. The findings suggest that the beneficial effects of EFA relative to IFA instructions on children's motor performance is identical across children with different levels of motor proficiency.

Saccadic eye movements and their influence on kinematics of several body segments in elderly while standing.

PURPOSE: It is well known that postural stability is influenced by visual stimuli. The influence of saccadic eye movement on postural control has been described, however, a specific response of different body segments has not been studied yet. Therefore, the aim of this study was to assess the effect of horizontal and vertical saccadic eye movements on postural stability with specific focus on upper trunk, lower trunk and lower limbs movement variability and complexity. METHODS: Eighteen elderly participants (age 70.3 ± 7.7 years) stood in bipedal stance in three visual conditions - horizontal saccades, vertical saccades and fixation. Accelerometers were attached to their lower back, sternum and shanks. Movement variability of each body segment was described by root-mean-square and sample entropy of acceleration. RESULTS: The results of the present study revealed significant influence of saccadic eye movements on anterior-posterior and vertical shanks, and vertical lower trunk movement variability described by root-mean-square. CONCLUSIONS: The correlations between results of the observed segments showed segment-specific variability patterns but generalised complexity pattern.

Jumping performance and take-off efficiency in two different age categories of female volleyball players.

PURPOSE: Vertical jump height is recognised as a determinant factor in elite volleyball performance. In previous studies there are different opinions on whether vertical jump height performance improves during maturation or not. The aim of this study was to assess the differences in jumping abilities in two different age groups of female volleyball players and to determine the take-off efficiency during repeated jumps. METHODS: Seventeen female volleyball players from two different age categories - adults and under 16 years - participated in this study. Quattro Jump 9290BA force platform (Kistler, Winterthur, Switzerland) was used to assess the jumping performance during squat jumps, counter movement jumps, and 45-second continuous jumps. RESULTS: Jumping performance did not differ significantly between the two groups. The main efficiency of the conversion of mechanical work into mechanical energy was only 24% and it decreased during the test. CONCLUSIONS: The influence of age on the jumping performance in a group of female volleyball players was not confirmed. Take-off efficiency was in both groups quite low and it did not improve during the test.

Standing balance of professional ballet dancers and non-dancers under different conditions.

Ballet training has been reported to positively influence balance ability. It is not entirely clear how improved balance ability manifests under standing conditions with different demands on postural control. The aim of the study was to compare balance of ballet dancers and non-dancers in a unipedal stance under different conditions. Twenty-five professional ballet dancers and twenty-five controls completed four unipedal standing balance tests: firm surface with eyes open and closed; foam mat surface with eyes open; and firm surface with eyes open immediately after performing ten 360° whole-body turns. The centre of pressure (COP) data were obtained with a force platform and the direction-specific standard deviations, velocities, and sample entropy of the COP displacement were computed. A three-way analysis of variance was used to compare groups, genders, and conditions. For standing immediately after performing ten turns, the postural sway parameters were significantly larger in the control group compared to the ballet dancers in both men and women. In this stance condition the values of postural sway and COP velocities in the control group were larger in the men compared to the women. For both genders in the control group all postural sway and COP velocity parameters were larger in standing with eyes closed and standing after performing 10 turns compared to standing with eyes open on both firm and foam surface. In the ballet dancers all COP velocity parameters were larger in standing with eyes closed compared to all other conditions. The results from the present study indicate that professional ballet dancers do not have a better general balance ability than untrained subjects.

Comparison of Plantar Pressure Distribution During Walking After Two Different Surgical Treatments for Calcaneal Fracture.

The aim of our study was to compare gait in terms of foot loading and temporal variables after 2 different operative approaches (the extended lateral approach [ELA] and sinus tarsi approach). Twenty-two patients who sustained an intra-articular calcaneal fracture underwent plantar pressure distribution measurements 6 months after surgery. Measurements were performed while patients walked on the pedobarography platform. The values of dynamic variables were significantly lower on the operated limb in the ELA. In the sinus tarsi approach, no differences were observed between the operated and uninjured limbs (UIN) at peak pressure and at maximal vertical force. The values of temporal variables (contact time of the foot and of the heel) between the operated and UIN differed in the ELA. The hypothesis that differences in foot load between operated and UIN will be more significant in the ELA was confirmed. Our results showed that the differences in loading and temporal variables between the operated and the UIN persisted 6 months after surgery in both methods. The operated limb was less loaded, with the tendency to shift the load toward the midfoot and forefoot. After the less invasive sinus tarsi approach, the dynamic and temporal variables on the operated limb were nearly the same as those on the healthy one. The sinus tarsi surgical approach can be recommended for treatment of displaced calcaneal fractures.

Local dynamic stability during gait for predicting falls in elderly people: A one-year prospective study.

Computing the local dynamic stability using accelerometer data from inertial sensors has recently been proposed as a gait measure which may be able to identify elderly people at fall risk. However, the assumptions supporting this potential were concluded as most studies implement a retrospective fall history observation. The aim of this study was to evaluate the potential of local dynamic stability for fall risk prediction in a cohort of subjects over the age of 60 years using a prospective fall occurrence observation. A total of 131 elderly subjects voluntarily participated in this study. The baseline measurement included gait stability assessment using inertial sensors and clinical examination by Tinetti Balance Assessment Tool. After the baseline measurement, subjects were observed for a period of one year for fall occurrence. Our results demonstrated poor multiple falls predictive ability of trunk local dynamic stability (AUC = 0.673). The predictive ability improved when the local dynamic stability was combined with clinical measures, a combination of trunk medial-lateral local dynamic stability and Tinetti total score being the best predictor (AUC = 0.755). Together, the present findings suggest that the medial-lateral local dynamic stability during gait combined with a clinical score is a potential fall risk assessment measure in the elderly population.