scholarly journals Multivariate Analyses of Balance Test Performance, Vestibular Thresholds, and Age

2017 ◽  
Vol 8 ◽  
Author(s):  
Faisal Karmali ◽  
María Carolina Bermúdez Rey ◽  
Torin K. Clark ◽  
Wei Wang ◽  
Daniel M. Merfeld
Keyword(s):  
Test Performance ◽  
Principal Component ◽  
Vertical Axis ◽  
Balance Test ◽  
Healthy Humans ◽  
Eyes Closed ◽  
Multiple Variable ◽  
Variation Explained ◽  
Romberg Test ◽  
Roll Tilt

We previously published vestibular perceptual thresholds and performance in the Modified Romberg Test of Standing Balance in 105 healthy humans ranging from ages 18 to 80 (1). Self-motion thresholds in the dark included roll tilt about an earth-horizontal axis at 0.2 and 1 Hz, yaw rotation about an earth-vertical axis at 1 Hz, y-translation (interaural/lateral) at 1 Hz, and z-translation (vertical) at 1 Hz. In this study, we focus on multiple variable analyses not reported in the earlier study. Specifically, we investigate correlations (1) among the five thresholds measured and (2) between thresholds, age, and the chance of failing condition 4 of the balance test, which increases vestibular reliance by having subjects stand on foam with eyes closed. We found moderate correlations (0.30–0.51) between vestibular thresholds for different motions, both before and after using our published aging regression to remove age effects. We found that lower or higher thresholds across all threshold measures are an individual trait that account for about 60% of the variation in the population. This can be further distributed into two components with about 20% of the variation explained by aging and 40% of variation explained by a single principal component that includes similar contributions from all threshold measures. When only roll tilt 0.2 Hz thresholds and age were analyzed together, we found that the chance of failing condition 4 depends significantly on both (p = 0.006 and p = 0.013, respectively). An analysis incorporating more variables found that the chance of failing condition 4 depended significantly only on roll tilt 0.2 Hz thresholds (p = 0.046) and not age (p = 0.10), sex nor any of the other four threshold measures, suggesting that some of the age effect might be captured by the fact that vestibular thresholds increase with age. For example, at 60 years of age, the chance of failing is roughly 5% for the lowest roll tilt thresholds in our population, but this increases to 80% for the highest roll tilt thresholds. These findings demonstrate the importance of roll tilt vestibular cues for balance, even in individuals reporting no vestibular symptoms and with no evidence of vestibular dysfunction.

scholarly journals Differences in Responses on the Modified Clinical Test of Sensory Interaction and Balance on Medium Firm and Medium Density Foam in Healthy Controls and Patients with Vestibular Disorders

2020 ◽  
Vol 5 (1) ◽  
pp. 1-8
Author(s):  
Helen S. Cohen ◽  
Haleh Sangi-Haghpeykar
Keyword(s):  
Test Performance ◽  
Clinical Decision Making ◽  
Head Movements ◽  
Clinical Test ◽  
Medium Density ◽  
Foam Density ◽  
Vestibular Disorders ◽  
Trial Duration ◽  
Balance Test ◽  
Eyes Closed

Purpose: To determine whether foam density affects modified Romberg balance test performance. Materials and Methods: Controls and patients with vestibular disorders performed Romberg tests on medium and medium firm foam, with their eyes closed and the head still and moving in yaw and pitch. The trial duration and number of head movements were measured. Results: Subjects aged >60 years performed longer and with more head movements on medium firm foam than on medium foam. Older controls did not differ between medium firm and medium foam. Older patients had higher scores on head-still and head-yaw trials on medium firm foam versus medium foam but pitch trials did not differ. Females, controls, and patients had longer trial durations and more head movements on medium firm foam than on medium density foam; male controls did not differ by foam density. Male patients differed in yaw trials. Conclusion: Foam density affects scores. Clinical decision-making may be adversely affected if the clinician uses foam of a density that is not the same as that of the foam that was used in the studies that developed descriptive statistics, sensitivity, and specificity.

The Effect of Sex, Sport Participation, and Concussion History on Baseline Concussion Balance Test Performance in Division-I Collegiate Athletes

Neurology ◽  
2021 ◽  
Vol 98 (1 Supplement 1) ◽  
pp. S19.1-S19
Author(s):  
Carolina Quintana ◽  
Nathan Morelli ◽  
Morgan L. Andrews ◽  
Madison Kelly ◽  
Nicholas Heebner ◽  
...  
Keyword(s):  
Test Performance ◽  
Sport Participation ◽  
Postural Sway ◽  
Collegiate Athletes ◽  
Sports Participation ◽  
Division I ◽  
Balance Performance ◽  
Balance Test ◽  
Eyes Closed ◽  
Concussion History

ObjectiveExplore the effect of baseline characteristics such as sex, sport, and concussion history on the Concussion Balance Test (COBALT) performance in collegiate athletes.BackgroundThe COBALT is a recently developed clinical balance assessment specifically for athletic populations following concussion. The task conditions of the COBALT are designed to challenge sensory integration and reweighting processing underlying postural control. It has been documented that balance performance is influenced by factors such as sex and sport in collegiate athletes.Design/MethodsOne-hundred twenty seven collegiate athletes (77 male, 50 female; age: 19.81 ± 1.39; height: 68.77 ± 5.57 in; mass: 80.98 ± 26.15 kg), who participated in Division-I football, soccer, or cheerleading were included. Participants completed the 4 baseline conditions (Condition 3, 4, 7, 8) of the COBALT. Condition 3 (C3) included a side-to-side headshake with eyes closed. For Condition 4 (C4) the participant stood with hands clasped, elbows extended, and thumbs up while rotating their trunk side-to-side, visually focusing on their thumbs. Conditions 7 (C7) and 8 (C8) repeated C3 and C4 on a foam surface. Two 20-second trials of each condition were completed on a forceplate and the mean angular sway velocity (°/s) were calculated and number of errors were counted. ANOVAs and ANCOVAs were used to assess the potential effects on COBALT performance.ResultsThere were no significant differences in postural sway for any COBALT condition based on sex (p > 0.05). Females demonstrated more errors than males on C7 (p < 0.001). Cheerleaders had more balance errors compared to football athletes for C3 and C7 (p < 0.05) and soccer athletes for C7 (p < 0.05). Concussion history did not have an effect on COBALT performance (p > 0.05).ConclusionsUnderstanding factors that may influence COBALT performance at baseline may enhance concussion evaluation in collegiate athletes with suspected balance deficits following concussion. While concussion history had no effect, sex and sports participation may influence performance and should be considered when interpreting COBALT results post-concussion.

Physical fitness of rhythmic gymnasts depending on age and level of sports achievements

2020 ◽  
Vol 30 (91) ◽  
pp. 29-36
Author(s):  
Katarzyna Sterkowicz-Przybycień ◽  
Paula Fundament
Keyword(s):  
Physical Fitness ◽  
Body Height ◽  
Age Groups ◽  
Standing Position ◽  
Time Duration ◽  
Balance Test ◽  
Eyes Closed ◽  
Fitness Tests ◽  
Rhythmic Gymnasts ◽  
Better Than

Aim. The aim of this study was to compare the indices of physical development, frequency and time duration of training, and the results of physical fitness tests depending on age and level of sports achievements among rhythmic gymnasts. Materials and methods. The study comprised 36 rhythmic gymnasts: Gr1 (n=13, 9.0±1.0 years), Gr2 (n=11, 11.36±0.5 years), Gr3 (n=12, 14.27±0.7 years). After standardised sports interview, the groups with lower level of sports achievements (LSL) (n=20) and higher level of sports achievements (HSL) (n=16) were defined. Measurements of body height and mass were performed. The study participants performed the broad jump test, Unipedal Stance Test with Eyes Open (UPST-EO) and Eyes Closed (EC), and the rhythmic gymnastics specific coordinative test with a hoop. Results. The number of training sessions per week and their duration did not depend on age. The results of the broad jump were significantly different for groups Gr1, Gr2 and Gr3 (F=27.02, p<0.01). The average results for the 3 trials of UPST-EO in Gr2 and Gr3 were better than in Gr1 (F=5.51, p=0.008). The average result of UPST-EC for Gr3 was also significantly better than for Gr1 (W=9.53, p=0.008). The hoop test showed differences for all age groups Gr1<Gr3<Gr2 (F=11.55, p<0.001). HSL athletes were significantly different from LSL in frequency and duration of training, average results from 3 trials of UPST-EO, UPSTEC and the best result of UPST-EC (p<0.05). Conclusions. Differences between groups in physical fitness tests results depended on gymnasts’ age and showed their usefulness in the control of training at a particular stage of sports development. HSL gymnasts predominated over LSL in results of the one-leg standing position postural balance test with eyes opened and closed. The detected differences can be useful for coaches in identifying and developing gymnastic talent.

Spatial orientation of postrotatory nystagmus during static roll tilt in cats

2002 ◽  
Vol 12 (1) ◽  
pp. 15-23
Author(s):  
Keiko Yasuda ◽  
Hiroaki Fushiki ◽  
Rinnosuke Wada ◽  
Yukio Watanabe
Keyword(s):  
Spatial Orientation ◽  
Vertical Axis ◽  
Longitudinal Axis ◽  
Velocity Storage ◽  
Slow Phase ◽  
Storage Mechanism ◽  
Spatial Disorientation ◽  
Acceleration And Deceleration ◽  
Eye Velocity ◽  
Roll Tilt

While the stimulation of otolith inputs reduces the duration of postrotatory nystagmus (PRN), there is still room for dialogue about the effect of static tilt on the orientation of PRN. We studied one possible influence of static roll tilt on the spatial orientation of PRN in cats. The animal was rotated about an earth-vertical axis (EVA) at a constant velocity of 100 deg/s with an acceleration and deceleration of 120 deg / s 2 . Within two seconds after stopping EVA rotation, the animal was passively tilted at 45 deg/s about its longitudinal axis by as much as ± 90 deg in steps of 15 deg. Eye movements were measured with magnetic search coils. The angle of the PRN plane and its slow phase eye velocity were measured. The time constant of PRN decreased with an increase in roll tilt. The PRN plane remained earth horizontal within a range of ± 30 deg roll tilt. Beyond this range, the velocity of PRN decreased too rapidly to measure any change in orientation. Our results indicate a spatially limited and temporally short interaction of the semicircular canal and otolith signals in the velocity storage mechanism of cat PRN. Our data, along with previous studies, suggest that different species show different solutions to the problem of the imbalance and spatial disorientation during contradictory stimuli.

Geometrical Variability Modelling of Axial Compressor Blisk Aerofoils and Evaluation of Impact on the Forced Response Problem

2020 ◽  
Author(s):  
Marco Gambitta ◽  
Arnold Kühhorn ◽  
Sven Schrape
Keyword(s):  
Computational Models ◽  
Axial Compressor ◽  
Principal Component ◽  
Forced Response ◽  
Rotor Blades ◽  
Civil Aviation ◽  
Mode Shapes ◽  
Stochastic Representation ◽  
Compressor Blades ◽  
Multiple Variable

Abstract The present work focuses on the effect of the manufacturing geometrical variability on the high-pressure compressor of a turbofan engine for civil aviation. The deviations of the geometry over the axial compressor blades are studied and modeled for the representation in the computational models. Such variability is of particular interest for the forced response problem, where small deviations of the geometry from the ideal nominal model can cause significant differences in the vibrational responses. The information regarding the geometrical mistuning is extracted from a set of manufactured components surface scans of a blade integrated disk (blisk) rotor. The optically measured geometries are parameterized, defining a set of opportune variables to describe the deviations. The dimension of the variables domain is reduced using the principal component analysis approach and a reconstruction of the modeled geometries is performed for the implementation in CFD and FEM solvers. The generated model allows a stochastic representation of the variability, providing an optimal set of variables to represent it. The aeroelastic analyses considering geometry based mistuning is carried out on a test-rig case, focusing on how such variability can affect the modal forcing generated on the blades. The force generated by the unsteady pressure field over the selected vibrational mode shapes of the rotor blades is computed through a validated CFD model. The uncertainty quantification of the geometrical variability effect on the modal forcing is performed employing Monte Carlo methods on a reduced model for the CFD solution, based on a single passage multi-blade row setup. The amplitude shift of the unsteady modal forcing is studied for different engine orders. In particular the scatter of the main engine orders forcing amplitudes for the manufactured blades can be compared with the nominal responses to predict the possible amplification due to the geometrical variability. Finally the results are compared to a full assembly computational model to assess the influence of multiple variable blades.

scholarly journals Reactive Postural Responses to Continuous Yaw Perturbations in Healthy Humans: The Effect of Aging

Sensors ◽  
2019 ◽  
Vol 20 (1) ◽  
pp. 63 ◽  
Author(s):  
Ilaria Mileti ◽  
Juri Taborri ◽  
Stefano Rossi ◽  
Zaccaria Del Prete ◽  
Marco Paoloni ◽  
...  
Keyword(s):  
Older Adults ◽  
Balance Control ◽  
Center Of Mass ◽  
Community Dwelling ◽  
Body Segments ◽  
Healthy Humans ◽  
Eyes Closed ◽  
Age Related ◽  
Postural Responses ◽  
Mass Displacement

Maintaining balance stability while turning in a quasi-static stance and/or in dynamic motion requires proper recovery mechanisms to manage sudden center-of-mass displacement. Furthermore, falls during turning are among the main concerns of community-dwelling elderly population. This study investigates the effect of aging on reactive postural responses to continuous yaw perturbations on a cohort of 10 young adults (mean age 28 ± 3 years old) and 10 older adults (mean age 61 ± 4 years old). Subjects underwent external continuous yaw perturbations provided by the RotoBit1D platform. Different conditions of visual feedback (eyes opened and eyes closed) and perturbation intensity, i.e., sinusoidal rotations on the horizontal plane at different frequencies (0.2 Hz and 0.3 Hz), were applied. Kinematics of axial body segments was gathered using three inertial measurement units. In order to measure reactive postural responses, we measured body-absolute and joint absolute rotations, center-of-mass displacement, body sway, and inter-joint coordination. Older adults showed significant reduction in horizontal rotations of body segments and joints, as well as in center-of-mass displacement. Furthermore, older adults manifested a greater variability in reactive postural responses than younger adults. The abnormal reactive postural responses observed in older adults might contribute to the well-known age-related difficulty in dealing with balance control during turning.

scholarly journals Applying the Minimal Detectable Change of a Static and Dynamic Balance Test Using a Portable Stabilometric Platform to Individually Assess Patients with Balance Disorders

Healthcare ◽  
2020 ◽  
Vol 8 (4) ◽  
pp. 402 ◽  
Author(s):  
Juan De la Torre ◽  
Javier Marin ◽  
Marco Polo ◽  
José J. Marín
Keyword(s):  
Center Of Pressure ◽  
Balance Control ◽  
Dynamic Balance ◽  
Static Balance ◽  
Minimal Detectable Change ◽  
Detectable Change ◽  
Balance Test ◽  
Balance Disorders ◽  
Eyes Closed ◽  
Specialist Physician

Balance disorders have a high prevalence among elderly people in developed countries, and falls resulting from balance disorders involve high healthcare costs. Therefore, tools and indicators are necessary to assess the response to treatments. Therefore, the aim of this study is to detect relevant changes through minimal detectable change (MDC) values in patients with balance disorders, specifically with vertigo. A test-retest of a static and dynamic balance test was conducted on 34 healthy young volunteer subjects using a portable stabilometric platform. Afterwards, in order to show the MDC applicability, eight patients diagnosed with balance disorders characterized by vertigo of vestibular origin performed the balance test before and after a treatment, contrasting the results with the assessment by a specialist physician. The balance test consisted of four tasks from the Romberg test for static balance control, assessing dynamic postural balance through the limits of stability (LOS). The results obtained in the test-retest show the reproducibility of the system as being similar to or better than those found in the literature. Regarding the static balance variables with the lowest MDC value, we highlight the average velocity of the center of pressure (COP) in all tasks and the root mean square (RMS), the area, and the mediolateral displacement in soft surface, with eyes closed. In LOS, all COP limits and the average speed of the COP and RMS were highlighted. Of the eight patients assessed, an agreement between the specialist physician and the balance test results exists in six of them, and for two of the patients, the specialist physician reported no progression, whereas the balance test showed worsening. Patients showed changes that exceeded the MDC values, and these changes were correlated with the results reported by the specialist physician. We conclude that (at least for these eight patients) certain variables were sufficiently sensitive to detect changes linked to balance progression. This is intended to improve decision making and individualized patient monitoring.

Sign in / Sign up

Export Citation Format

Share Document