Control of sway using vibrotactile feedback of body tilt in patients with moderate and severe postural control deficits

2005 ◽  
Vol 15 (5-6) ◽  
pp. 313-325
Author(s):  
C. Wall ◽  
E. Kentala
Keyword(s):  
Postural Control ◽  
Postural Stability ◽  
Body Motion ◽  
Body Tilt ◽  
Joint Movement ◽  
Foot Pressure ◽  
Eyes Closed ◽  
The Subject ◽  
Anterior Posterior ◽  
Vibrotactile Display

We evaluated the effect of the vibrotactile display of body tilt upon the postural stability of vestibulopathic subjects during standing. Two groups were studied: those with moderate and with severe deficits as defined by postural stability test scores. They were studied under conditions of distorted sensory input, and during anterior-posterior perturbations. Seventeen subjects, with uni- or bilateral vestibular deficits, as determined by electronystagmography and vertical axis rotation, were tested using Equitest® computerized dynamic posturography (CDP). Based on their performance on the CDP they were divided into two groups having either moderate (nine subjects) or severe (eight subjects) postural control deficits. Their anterior-posterior (A/P) body motion at the waist was measured with a micromechanical rate gyroscope and a linear accelerometer. The resulting tilt estimate was displayed by a vibrotactile array attached to the torso. The vibration served as a tilt feedback to the subject. The subject's performance was evaluated using the root-mean-square (RMS) of both the A/P body motion and center-of-pressure (CoP) estimates. Sensory distortions were introduced using the Equitest® Sensory Organization Tests (SOT). These tests are designed to distort A/P sensory inputs while standing. The SOT 5 distorts proprioceptive information about ankle joint movement, while the subject stands eyes-closed on a moving support platform that measures foot pressure. The SOT 6 adds distorted visual information about body movement instead of testing with eyes closed. Perturbations were introduced using the Equitest® Motor Control Tests (MCT). These move the support platform forward or backward with small, medium and large displacements in the horizontal plane while measuring subjects' foot pressure responses. We used the medium and large backward tests. Vibrotactile display of body tilt reduced the subjects' A/P sway and improved their balance. The finding was more evident for those subjects with severe deficits than those moderate ones. This trend was found for both SOT 5 and 6, as well as the medium and large MCT. Additionally, during the MCT, the peak deflection and mean recovery time also decreased significantly.

scholarly journals Time-to-Boundary Function to Study the Development of Upright Stance Control in Children

2017 ◽  
Vol 11 (1) ◽  
pp. 49-58
Author(s):  
Carmen D'Anna ◽  
Maurizio Schmid ◽  
Andrea Scorza ◽  
Salvatore A. Sciuto ◽  
Luisa Lopez ◽  
...  
Keyword(s):  
Standard Deviation ◽  
Postural Control ◽  
Postural Stability ◽  
Age Groups ◽  
Boundary Function ◽  
Mean Value ◽  
Upright Stance ◽  
Eyes Closed ◽  
The Mean ◽  
Spatio Temporal

Background: The development of postural control across the primary school time horizon is a complex process, which entails biomechanics modifications, the maturation of cognitive ability and sensorimotor organization, and the emergence of anticipatory behaviour. Postural stability in upright stance has been thus object of a multiplicity of studies to better characterize postural control in this age span, with a variety of methodological approaches. The analysis of the Time-to-Boundary function (TtB), which specifies the spatiotemporal proximity of the Centre of Pressure (CoP) to the stability boundaries in the regulation of posture in upright stance, is among the techniques used to better characterize postural stability in adults, but, as of now, it has not yet been introduced in developmental studies. The aim of this study was thus to apply this technique to evaluate the development of postural control in a sample population of primary school children. Methods: In this cross-sectional study, upright stance trials under eyes open and eyes closed were administered to 107 healthy children, divided into three age groups (41 for Seven Years' Group, Y7; 38 for Nine Years' Group, Y9; 28 for Eleven Years' Group, Y11). CoP data were recorded to calculate the Time-to-Boundary function (TtB), from which four spatio-temporal parameters were extracted: the mean value and the standard deviation of TtB minima (Mmin, Stdmin), and the mean value and the standard deviation of the temporal distance between two successive minima (Mdist, Stddist). Results: With eyes closed, Mmin and Stdmin significantly decreased and Mdist and Stddist increased for the Y7 group, at Y9 Mmin significantly decreased and Stddist increased, while no effect of vision resulted for Y11. Regarding age groups, Mmin was significantly higher for Y9 than Y7, and Stdmin for Y9 was higher than both Y7 and Y11; Mdist and Stddist resulted higher for Y11 than for Y9. Conclusion: From the combined results from the spatio-temporal TtB parameters, it is suggested that, at 9 years, children look more efficient in terms of exploring their limits of stability than at 7, and at 11 the observed TtB behaviour hints at the possibility that, at that age, they have almost completed the maturation of postural control in upright stance, also in terms of integration of the spatio-temporal information.

Reduction of Postural Sway by Use of a Vibrotactile Balance Prosthesis Prototype in Subjects with Vestibular Deficits

2003 ◽  
Vol 112 (5) ◽  
pp. 404-409 ◽  
Author(s):  
Erna Kentala ◽  
Jason Vivas ◽  
Conrad Wall
Keyword(s):  
Postural Sway ◽  
Body Tilt ◽  
Vibrotactile Feedback ◽  
Dynamic Posturography ◽  
Sensory Organization ◽  
The Subject ◽  
Linear Accelerometer ◽  
Subject Performance ◽  
Vestibular Deficit ◽  
Anterior Posterior

To evaluate the effectiveness of a prototype vibrotactile balance prosthesis in maintaining balance during dynamic posturography, we studied 6 subjects with unilateral or bilateral vestibular deficit by means of Equitest computerized dynamic posturography (CDP). Their anterior-posterior (AP) sway at the small of the back was measured with a micromechanical rate gyroscope and a linear accelerometer. The resulting tilt estimate was displayed by a vibrotactile array attached to the torso. The vibration served as tilt feedback to the subject. Subject performance was evaluated with the tilt performance index (TPI), which is the inverse of the root-mean-square of tilt. We found that the balance prosthesis reduced the subjects' AP sway. The subjects' results without the balance prosthesis on CDP sensory organization tests (SOTs) 5 and 6 were compared to results with the prosthesis. The average TPI increased significantly (p < .05) when vibrotactile feedback was used as compared to the unaided condition. This finding was true for both SOTs 5 and 6. We conclude that vibrotactile feedback of estimated AP body tilt improved the subjects' ability to perform selected CDP tests. Some of the subjects were able to stand throughout the test with the device turned on, whereas they otherwise constantly fell.

Effect of Head Orientation on Human Postural Stability Following Unilateral Vestibular Ablation

1991 ◽  
Vol 1 (2) ◽  
pp. 153-160
Author(s):  
Charles R. Fox ◽  
Gary D. Paige
Keyword(s):  
Postural Control ◽  
Postural Stability ◽  
Postural Sway ◽  
Normal Subjects ◽  
Head Orientation ◽  
Support Surface ◽  
Eyes Closed ◽  
Vestibular Information ◽  
Postural Equilibrium ◽  
Vestibular Pathology

Effective interpretation of vestibular inputs to postural control requires that orientation of head on body is known. Postural stability might deteriorate when vestibular information and neck information are not properly coupled, as might occur with vestibular pathology. Postural sway was assessed in unilateral vestibulopathic patients before and acutely, 1,4, and 18+ months after unilateral vestibular ablation (UVA) as well as in normal subjects. Postural equilibrium with eyes closed was quantified as scaled pk-pk sway during 20 s trials in which the support surface was modulated proportionally with sway. Subjects were tested with the head upright and facing forward, turned 45∘ right, and 45∘ left. Equilibrium was uninfluenced by head orientation in normal subjects. In contrast, patients after UV A showed both a general reduction in stability and a right/left head orientation-dependent asymmetry. These abnormalities adaptively recovered with time. It is concluded that vestibular inputs to postural control are interpreted within a sensory-motor context of head-on-body orientation.

scholarly journals Interactive Sensor-Based Balance Training in Older Cancer Patients with Chemotherapy-Induced Peripheral Neuropathy: A Randomized Controlled Trial

Gerontology ◽  
2015 ◽  
Vol 62 (5) ◽  
pp. 553-563 ◽  
Author(s):  
Michael Schwenk ◽  
Gurtej S. Grewal ◽  
Dustin Holloway ◽  
Amy Muchna ◽  
Linda Garland ◽  
...  
Keyword(s):  
Peripheral Neuropathy ◽  
Postural Control ◽  
Cancer Patients ◽  
Fear Of Falling ◽  
Wearable Sensors ◽  
Balance Training ◽  
Joint Movement ◽  
Eyes Closed ◽  
Closed Position ◽  
Older Cancer Patients

Background: Cancer patients with chemotherapy-induced peripheral neuropathy (CIPN) have deficits in sensory and motor skills leading to inappropriate proprioceptive feedback, impaired postural control, and fall risk. Balance training programs specifically developed for CIPN patients are lacking. Objective: This pilot study investigated the effect of an interactive motor adaptation balance training program based on wearable sensors for improving balance in older cancer patients with CIPN. Methods: Twenty-two patients (age: 70.3 ± 8.7 years) with objectively confirmed CIPN [vibration perception threshold (VPT) >25 V] were randomized to either an intervention (IG) or a control (CG) group. The IG received interactive game-based balance training including repetitive weight shifting and virtual obstacle crossing tasks. Wearable sensors provided real-time visual/auditory feedback from the lower limb trajectory and allowed the perception of motor errors during each motor action. The CG received no exercise intervention and continued their normal activity. Outcome measures were changes in sway of ankle, hip, and center of mass (CoM) in both mediolateral and anteroposterior (AP) directions during 30-second balance tests with increasing task difficulty [i.e. standing in feet-closed position with eyes open (EO) and eyes closed (EC), and in semi-tandem position with EO] at baseline and after the intervention. Additionally, gait performance (speed, variability) and fear of falling [Falls Efficacy Scale-International (FES-I)] were measured. Results: Training was safe despite the participants' impaired health status, great severity of CIPN (VPT 49.6 ± 26.7 V), and great fear of falling (FES-I score 31.37 ± 11.20). After the intervention, sway of hip, ankle, and CoM was significantly reduced in the IG compared to the CG while standing in feet-closed position with EO (p = 0.010-0.022, except AP CoM sway) and in semi-tandem position (p = 0.008-0.035, except ankle sway). No significant effects were found for balance with EC, gait speed, and FES-I score (p > 0.05). Conclusions: This proof-of-concept study demonstrates that older cancer patients with CIPN can significantly improve their postural balance with specifically tailored, sensor-based exercise training. The training approach has potential as a therapy for improving CIPN-related postural control deficits. However, future studies comparing the proposed technology-based training with traditional balance training are required to evaluate the benefit of the interactive joint movement feedback.

scholarly journals Correlation between body weight and postural control in healthy individuals using sway meter

2019 ◽  
Vol 16 (2) ◽  
pp. 36-41
Author(s):  
Tharani G ◽  
Vedha Varshini M G ◽  
Senthil Nathan C V ◽  
Mohan Kumar G ◽  
Kamatchi K
Keyword(s):  
Body Weight ◽  
Postural Control ◽  
Body Mass ◽  
Strong Correlation ◽  
Daily Living ◽  
Postural Sway ◽  
The Body ◽  
Healthy Individuals ◽  
Eyes Closed ◽  
Anterior Posterior

BACKGROUND: Postural control is critical for ensuring a safety activity of daily living. Individuals with poor stability are more prone to fall while doing activities of daily living. A certain level of sway is essentially present due to small perturbation within the body during shifting body weight from one to other foot, breathing, etc. The purpose of this study was to analyze the correlation between body mass and postural control in normal, lean and obese individual. AIMS: to analyze the correlation between body mass and postural control in healthy individuals using sway meter. MATERIALS AND METHODS: This is an observational study done with 75 participants. Both male and female healthy individuals between 18-23 years were included in this study. Individuals with any musculoskeletal injuries, neurological conditions, peripheral artery disease and pregnant women were excluded from the study. BMI of each participant was calculated and assigned into three groups. Group A-lean, group B-normal and group C-obese. Postural control was analyzed for each group by using sway meter; level of postural sway was compared between groups A, B C. RESULTS: On comparing mean values of groups A, B and C there was a positive association and strong correlation between body mass index and postural control with eye open and eye closed in anterior, posterior and postural sway towards left between the groups at (P 0.05). However, there was a negative association and weak correlation between BMI and postural control with eye open eye closed in postural sway towards right between the groups at (P 0.05). CONCLUSIONS: This study reveals that there is strong correlation between BMI and postural control. Subjects in eyes closed and eyes opened conditions showed sway in anterior, posterior and left directions but there was less sway towards right side direction.

scholarly journals Improving postural stability among people with lower-limb amputations by tactile sensory substitution

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Lijun Chen ◽  
Yanggang Feng ◽  
Baojun Chen ◽  
Qining Wang ◽  
Kunlin Wei
Keyword(s):  
Postural Control ◽  
Lower Limb ◽  
Postural Stability ◽  
Pressure Sensors ◽  
Interaction Force ◽  
The Body ◽  
Sensory Substitution ◽  
Foot Pressure ◽  
Vibration Intensity ◽  
Visual Disturbances

Abstract Background For people with lower-limb amputations, wearing a prosthetic limb helps restore their motor abilities for daily activities. However, the prosthesis's potential benefits are hindered by limited somatosensory feedback from the affected limb and its prosthesis. Previous studies have examined various sensory substitution systems to alleviate this problem; the prominent approach is to convert foot–ground interaction to tactile stimulations. However, positive outcomes for improving their postural stability are still rare. We hypothesized that the sensory substiution system based on surrogated tactile stimulus is capable of improving the standing stability among people with lower-limb amputations. Methods We designed a wearable device consisting of four pressure sensors and two vibrators and tested it among people with unilateral transtibial amputations (n = 7) and non-disabled participants (n = 8). The real-time measurements of foot pressure were fused into a single representation of foot–ground interaction force, which was encoded by varying vibration intensity of the two vibrators attached to the participants’ forearm. The vibration intensity followed a logarithmic function of the force representation, in keeping with principles of tactile psychophysics. The participants were tested with a classical postural stability task in which visual disturbances perturbed their quiet standing. Results With a brief familiarization of the system, the participants exhibited better postural stability against visual disturbances when switching on sensory substitution than without. The body sway was substantially reduced, as shown in head movements and excursions of the center of pressure. The improvement was present for both groups of participants and was particularly pronounced in more challenging conditions with larger visual disturbances. Conclusions Substituting otherwise missing foot pressure feedback with vibrotactile signals can improve postural stability for people with lower-limb amputations. The design of the mapping between the foot–ground interaction force and the tactile signals is essential for the user to utilize the surrogated tactile signals for postural control, especially for situations that their postural control is challenged.

scholarly journals Trends in the Analysis of Static Balance

2020 ◽  
Vol 1 (2) ◽  
Author(s):  
Vilma Juodžbalienė ◽  
Kazimieras Muckus
Keyword(s):  
Postural Control ◽  
Physiological Parameters ◽  
Quiet Standing ◽  
Static Balance ◽  
Foot Pressure ◽  
Postural Control System ◽  
Balance Disorders ◽  
Dependent Variables ◽  
Center Of Foot Pressure ◽  
Anterior Posterior

The aim of the paper was to discuss the trends in the analysis of static balance and relation between physiological parameters and characteristics of posturograms. Static balance is ability to keep steady posture in certain stance [2, 3]. Posturography is one of most popular research methods of static balance [10, 11]. During the last decade it was maintained that the most informative dependent variables defining postural stability were the amplitude of the center of foot pressure (COP) sway in anterior-posterior and mediolateral directions, the length of the COP pathway and the area of the COP sway [9, 15]. The output of the posturograms registered during quiet standing is irregular and erratic [14]. Therefore, methods analyzing the structure of the posturograms are very topical for physiology and Rehabilitation science. The scientists attempt to determine certain noise and oscillation patterns in the posturogram [20]. According to researchers [14], the structure and roughness or smoothness of the posturogram could reflect the changes in postural control system. It is still questionable which of the methods analyzing the posturogram outcomes could be the most informative and useful for the diagnostics of postural control disorders. It is important to be able to repeat the scientific study, but it is still complicated to solve tasks related to postural control disorders diagnostics and the evaluation of the treatment means effectiveness. It is important to define the relation between physiological parameters and characteristics of posturograms in order to apply the posturography for balance disorders diagnostics. We suppose that methods of posturogram structure analysis could improve the differential balance disorders diagnostics essentially.Keywords: static balance, static posturography, center of foot pressure.

scholarly journals Prevalence of floating toe and its relationship with static postural stability in children: The Yamanashi adjunct study of the Japan Environment and Children’s Study (JECS-Y)

2021 ◽  
Author(s):  
Taro Fujimaki ◽  
Masanori Wako ◽  
Kensuke Koyama ◽  
Naoto Furuya ◽  
Ryoji Shinohara ◽  
...  
Keyword(s):  
Postural Stability ◽  
Center Of Pressure ◽  
The Body ◽  
Ground Contact ◽  
Foot Pressure ◽  
Eyes Closed ◽  
Stability Measurement ◽  
Eyes Open ◽  
The Relationship ◽  
Very High

AbstractFloating toe (FT) is a frequently seen condition in which a toe is inadequately in contact with the ground. Although toes play an important role in stabilizing standing posture and walking, many aspects of the effects of FT on the body remain unclear. To our knowledge, there have been no reports about the relationship between FT and postural stability, especially in children. This study aimed to clarify the prevalence of FT and its relationship with static postural stability in children. Of the 400 children aged 8 years who participated in our cohort study, 396, who were examined for static postural stability, were included in this study. Postural stability and FT were assessed using a foot pressure plate. The sway path length of the center of pressure and the area of the ellipse defined as the size of the area marked by the center of pressure were measured as an evaluation of static postural stability. We calculated the “floating toe score (FT score: small FT score indicates insufficient ground contact of the toes)” using the image of the plantar footprint obtained at the postural stability measurement. The FT rate was very high at more than 90%, and the FT score in the eyes-closed condition was significantly higher than that in the eyes-open condition in both sexes. The FT score significantly correlated with the center of pressure path and area. Our results suggest that ground contact of the toes is not directly related to static postural stability in children, but it may function to stabilize the body when the condition becomes unstable, such as when the eyes are closed.

scholarly journals Postural instability in subjects with parkinson’s disease undergoing different sensory pitfalls

2017 ◽  
Vol 18 (4) ◽  
Author(s):  
Thaís Cardoso Da Silva ◽  
Lilian Assunção Felippe ◽  
Rodrigo Luiz Carregaro ◽  
Gustavo Christofoletti
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Visual Information ◽  
Postural Stability ◽  
Body Position ◽  
Postural Instability ◽  
Sensory Stimuli ◽  
Eyes Closed ◽  
The Impact ◽  
Anterior Posterior

AbstractPurpose. Previous research has reported postural instability in subjects with Parkinson’s disease (PD). However, there are still doubts about the effect of sensory stimuli on one’s balance. In this study, we further investigated the stabilometric measures of individuals with PD, analysing the impact of different sensory stimuli on the outcomes. Methods. The total of 26 participants (13 with PD and 13 matched control peers) were submitted to 8 sensorimotor dynamics differing in relation to support base (30 cm vs. 10 cm, feet in parallel vs. feet in semi-tandem position), contact surface (foam vs. no foam), and visual conditions (eyes open vs. eyes closed). The measures used to assess one’s balance were body position in space, area of support base, and velocity of postural control. The variables involved the anterior-posterior and the mediolateral axes. Participants with PD were evaluated during the off medication state. Mann-Whitney U test and Friedman’s test were applied to carry out inter- and intra-group comparisons. Significance was set at 5%. Results. Cross-sectional analyses illustrated that tasks with sensory pitfalls impacted postural stability to a larger extent in PD subjects. The differences were found in anterior-posterior body position, area of support base, anterior-posterior velocity, and mediolateral velocity. Complementary analyses confirmed considerable instability on balance when support bases were small and visual information was absent (p < 0.05). Conclusions. The current results confirm worse postural stability response in subjects with PD and highlight that the interference of the sensory pitfalls is notable when individuals are off medication.

Quantifying the Contributions of the Flexor Digitorum Brevis Muscle on Postural Stability

Motor Control ◽  
2015 ◽  
Vol 19 (3) ◽  
pp. 161-172 ◽  
Author(s):  
Liria Akie Okai ◽  
André Fabio Kohn
Keyword(s):  
Postural Control ◽  
Postural Stability ◽  
Center Of Pressure ◽  
Human Foot ◽  
Sustained Activity ◽  
Torque Generation ◽  
Flexor Digitorum Brevis ◽  
The Subject ◽  
Flexor Digitorum ◽  
Intrinsic Muscles

Surprisingly little attention has been devoted to the role played by the intrinsic muscles of the human foot. The aim of this study was to quantify the capabilities of the flexor digitorum brevis (FDB) muscle to contribute to upright postural control. The approaches consisted of analysis of the effects of FDB contraction elicited by external electrical stimulation and quantification of the magnitude of FDB torque generation. The results showed the FDB can produce significant changes in static posture by itself as shown by changes in the center of pressure. Moreover, the FDB contribution to counterbalance the gravity’s toppling force was estimated at around 14.5% of the total required active torque at the ankle to keep the subject from falling. A posteriori functional analysis during horizontal perturbations showed high and self-sustained activity of FDB. These results demonstrated that the FDB has a significant capability of contributing to postural control.

Sign in / Sign up

Export Citation Format

Share Document