Efectos posturográficos de la maniobra de Epley en pacientes con vértigo posicional paroxístico del canal posterior / Posturographic effects of the Epley maneuver on patients with benign paroxysmal positional vertigo of the posterior canal

Resumen Introducción: El vértigo posicional paroxístico benigno (VPPB) es la afección periférica más común en las enfermedades otoneurológicas. Con el reposicionamiento de partículas se busca eliminar el vértigo y sus síntomas asociados como lo son el mareo residual y la inestabilidad. Objetivo: Determinar si la maniobra de reposicionamiento de Epley (MRE) produce una modificación significativa del control postural (CP) en aquellos pacientes con VPPB de canal semicircular posterior (VPPB-CSC-P). Material y Método: Se realizó un estudio descriptivo prospectivo en una muestra de 21 pacientes con diagnóstico de VPPB-CSC-P. Comparamos el desplazamiento, la velocidad y el área del centro de presión (CoP) antes y después de la MRE. Resultados: La velocidad y el área de la CoP estudiada por posturografía computarizada muestra una disminución significativa en sus valores después de la MRE, mientras que el desplazamiento de la CoP se mantuvo sin cambios. Conclusión: La MRE ejecutada en pacientes con VPPB-CSC-P produce una modulación en el control de la CoP, demostrada por la disminución de la velocidad y el área de desplazamiento de la CoP. El éxito de la MRE produce modulación del CP.

Abstract Introduction: Benign paroxysmal positional vertigo (BPPV) is the most common peripheral condition in otoneurologic diseases. With the repositioning of particles, the aim is to eliminate vertigo and its associated symptoms, such as residual dizziness and instability. Aim: To determine if the Epley repositioning maneuver (ERM) produces a significant modification of postural control (PC) in those patients with posterior semicircular canal BPPV (BPPV-CSC-P). Material and Method: A prospective descriptive study was carried out in a sample of 21 patients diagnosed with BPPV-CSC-P. We compared the displacement, velocity, and area of the center of pressure (CoP) before and after the Epley repositioning maneuver. Results: The velocity and the area of the CoP studied by computed posturography show a significant decrease in its values after the MRE, while the CoP shift remained unchanged. Conclusion: ERM performed in patients with BPPV-CSC-P produces an improvement in the control of the CoP, demonstrated by the decrease in the speed and the area of movement of the CoP. The success of the MRE produces modulation of the PC.

Postural control at posturography with virtual reality in the intercritical period of vestibular migraine / Controle postural à posturografia com realidade virtual no período intercrítico da migrânea vestibular

Abstract Introduction: Vestibular migraine is a condition that associates headache and vestibular symptoms. Objective: To evaluate body-balance with virtual reality posturography in vestibular migraine. Methods: A total of 26 patients in the intercritical period of vestibular migraine were compared by means of the Balance Rehabilitation UnitMT (Medical/Interacoustics) posturography with 30 controls, paired for age and gender. Results: There was no significant statistical difference (p = 0.121) in the limit of stability area (cm2) between the experimental group and the control group values. There were significant differences (p < 0.05) in the values of sway velocity (cm/s) in nine of ten evaluated sensory conditions and in the pressure center displacement area (cm2) values in eight of those ten sensory conditions in the comparison between the control group and the experimental group. Conclusion: Posturography with virtual reality can identify changes in the sway velocity and the pressure center displacement area, characterizing the inability to maintain postural control with and without visual deprivation in situations of visual conflict and vestibulovisual interaction,in the intercritical period of the vestibular migraine.

Resumo Introdução: A migrânea vestibular é um quadro clínico que associa cefaleia migranosa e sintomas vestibulares. Objetivo: Avaliar o controle postural à posturografia com realidade virtual no período intercrítico da migrânea vestibular. Método: Um total de 26 pacientes com migrânea vestibular no período intercrítico da afecção foram comparados comparados à posturografia do Balance Rehabilitation UnitTM (Medical/Interacoustics) a um grupo controle com 30 indivíduos hígidos pareados por idade e sexo. Resultados: Não houve diferença estatisticamente significante (p = 0,102) entre os valores da área do limite de estabilidade (cm2) entre o grupo experimental e o controle. Houve diferença significante (p < 0,05) nos valores da velocidade de oscilação (cm/s) em nove de dez condições sensoriais avaliadas e nos valores da área de deslocamento do centro de pressão (cm2) em oito destas dez condições sensoriais em comparação entre os grupos controle e experimental. Conclusão: A posturografia com realidade virtual pode identificar alterações da velocidade de oscilação e da área de deslocamento do centro de pressão, o que caracteriza a inabilidade para manter o controle postural com e sem privação da visão, em situações de conflito visual e interação vestibulovisual, no período intercrítico da migrânea vestibular.

Neuropathic pain in knee osteoarthritis

Abstract Background: This study aimed to investigate the relationship between the neuropathic pain in knee osteoarthritis with the body composition, anthropometric and postural features, physical function, and quality of life. Methods: Patients with primary knee osteoarthritis, 50-70 years of age, were included in the study and divided into Group 1 with neuropathic pain and Group 2 with no neuropathic pain according to Douleur Neuropathique-4. The groups were compared in terms of demographic, clinical, radiological, laboratory findings and anthropometric measurements, body composition, physical function tests, osteoarthritis severity, quality of life, and posturography. Results: 200 patients were included in the study. 98 (82.6% female) were in Group 1 and 102 (74.5% female) in Group 2. Age was higher in Group 1 compared to Group 2 [61 (50-70) and 57.5 (50-70), respectively, p= 0.03]. Symptom duration was also longer in Group 1 (5.21 ± 4.76 and 3.38 ± 3.58, p= 0.002). Body mass indices were 31.9 ± 5.6 and 30.1 ± 4.8 (p= 0.015). Kellgren-Lawrence class, Western Ontario and McMaster Osteoarthritis Index and Short Form-36 scores were more unfavorable in Group 1. Although fall risk was similar, stability and Fourier harmony indices were impaired in Group 1 compared to Group 2 especially when the visual and proprioceptive input was blocked. Conclusions: Almost half of the patients with knee osteoarthritis had neuropathic pain which was associated with longer symptom duration and higher age, lower education, higher body mass index, more severe radilogical findings, worse pain perception, lower physical function and quality of life, and lower stability.

Influence of gender on static balance in healthy community dwelling elderly: a comparison using posturography

Background: Background and need of study- Influence of gender on balance is still controversial. Previous researchers have done studies using traditional methods. These methods may fail to detect subtle changes in balance difference. A tool like posturography which is highly specific may help to for accurate assessment and hence precise conclusion. Aim was to compare balance scores of male and female elderly using modified Clinical Test of Sensory Interaction on Balance (CTSIB).Methods: There were 56 healthy elderly ambulating without an assistive device and free from any neurological and orthopedic problems were assessed for their balance abilities using mCTSIB of balance master(standing on firm surface with eyes open, with eyes closed, standing on foam surface with eyes open and with eyes closed). Sway velocity was assessed using Unpaired t test.Results: There was a no significant difference in scores of modified CTSIB between male and female elderly ( p value>0.005).Conclusions: Gender has no effect on static balance abilities between male and female elderly while performing modified clinical test of sensory interaction on balance.

Various Static And Dynamic Balance Measuring And Training Mechanical Tools In Patients With Clinical Conditions: A Literature Review

Background: Balance is defined as the ability to maintain a position within the limits of stability or base of support. It is indicated that postural control system plays an important role in maintenance of balance on the small support base. The complexity of balancing processes makes it challenging to assess balancing abilities in a concise, holistic approach. This study extends previous efforts by reviewing a large number of papers that use of various mechanical tools to assess postural balance and by providing a detailed overview of the common mechanical tools used to assess postural balance and gait. Methods: We searched the electronic database. The literature search produced a total of 302 items. After removal of duplicates, posters, other studies not mention mechanical tools to evaluate static and dynamic balance in clinical conditions, 28 papers met the inclusion criteria for this review. Results: This search selected 7 tools to assess trunk control in various clinical conditions: Inertial balance sensor, Computerised dynamic posturography, Biodex Balance System, Force plate., MatScan® pressure mat, Microsoft Kinect’s built-in RGB-D sensor and Clinical Test of sensory integration using Chinese lantern. Conclusion: Inertial as well as Microsoft Kinect’s built-in RGB-D sensors are cost effective, time effective, does not need a specific set up, analysis static balance as well as the gait parameters. This can therefore be chosen over other mechanical tools due to its better convenience and efficiency.

Change in Static Postural Stability after a Home‑based Exercise Program in Persons with Idiopathic Parkinson’s Disease - A Randomized Control Study

Introduction and Purpose:The most common form of parkinsonism is idiopathic Parkinson’s disease. The cardinal symptoms of idiopathicParkinson’s disease are tremor, rigidity, bradykinesia, posture and gait abnormalities, speech changes, depression, gastrointestinal issues,urinary problems, autonomic features, eye abnormalities, cognitive impairments, cranial nerve dysfunction, and swallowing dysfunction.Abnormalities of posture significantly affect activities of daily living in such patients. Static posturography is used to measure the balanceof an individual during standing. Asingle-blinded controlled trial comparing 4 weeks of outpatient physical therapy with no specific therapyshowed significant improvement in gait in patients with Parkinson’s disease. However, the gains were lost when the patients stoppedexercises at the end of the program. Hence, the authors felt that teaching a simple, implementable home-based exercise could benefitthese patients in improving their balance. Any change in static balance could be measured easily with a force platform.Methodology: A total of 62 clinically diagnosed patients with idiopathic Parkinson’s disease attending a tertiary care centerwere randomized into two groups, one rehabilitation group (those who were taught a simple home-based rehabilitation exerciseprogram on an outpatient basis) and a non-rehabilitation (control) group who were not taught the exercises. They were clinicallyevaluated and their center of pressure (COP) sway area was measured using a computerized static posturography instrument(force platform), at first visit, after 1 month, after 3 months, and after 5 months. The differences in their COP sway area betweenthe visits were compared between the two groups to see the change in postural stability.Results and Discussion: Atotal of 62 patients who satisfied the inclusion criteria were inducted in the study after informed consent. Themean age of the rehabilitation group (n = 32) was 58.66 years and the mean age of the non-rehabilitation group (n = 30) was 59.17 years.69% of the rehabilitation group were males and 31% were females, and in the non-rehabilitation group, 67% were males while 37%were females. The mean duration of disease in the rehabilitation group was 8.31 years and that in the non-rehabilitation group was8.67 years. Most of the variables did not show any significant difference, and hence, the groups were comparable. The baseline meanCOP sway area of the rehabilitation group was 76.53 mm2 and that of the non-rehabilitation group was 76.73 mm2. There was a 11.68%decrease in the COP sway area of the rehabilitation group at the end of the 1st month while the non-rehabilitation group had only 0.22%decrease. At the end of the study, i.e., at 5th month, there was a 32.05% decrease in the sway area from baseline in the rehabilitationgroup, indicating significant improvement in static balance. There was only 1.13% decrease in the sway area of the non-rehabilitationgroup. Both the P values were <0.001, and thus, our study revealed that a simple home-based rehabilitation exercise program taughton an outpatient basis to patients with idiopathic Parkinson’s disease can improve the balance in such patients.Conclusion: There was a statistically significant improvement in the static postural stability of patients with idiopathic Parkinson’sdisease who did exercise at home when compared to those who did not perform the home-based exercises. However, longterm studies need to be done to confirm whether this gain is long lasting.

Nintendo Wii Fit-Based Sleepiness Testing is Not Impaired by Contagious Sleepiness

Sleep deprivation may cause accidents, and it has deteriorating effects on health. A measurement of postural steadiness by a portable and affordable Nintendo Wii Fit balance board can be used to quantify a person's alertness. At work, people are under the influence of their environment—often other people—that may affect their alertness. This work investigates whether sleep deprivation among people is “contagious,” as quantified by sway measures. We measured 21 volunteers' postural steadiness while alert and sleep deprived. During the measurements, a screen placed in front of the participants showed a footage of either alert or sleep-deprived faces. We found a significant difference between the day time and night time steadiness, but found no effect resulting from watching footage of sleep-deprived people. This finding shows that a posturographic sleepiness tester quantifies physiological sleep deprivation, and is insensitive to the influence of social factors.

Relationship of Vertigo and Postural Instability in Patients With Vestibular Schwannoma

OBJECTIVES: Growth of vestibular schwannomas (VS) causes progressive vestibular symptoms and postural instability. Since the tumor grows slowly, compensation of decaying vestibular input may decrease subjective symptoms of dizziness. This study aims to estimate the relationship of subjective vestibular symptoms and objective postural instability in patients with VS. METHODS: A retrospective review of 18 patients newly diagnosed with VS and with subjective vertigo symptoms was performed. The results of vestibular function tests including the sensory organization test (SOT) using computerized dynamic posturography, caloric test, and self-report measures of subjective dizziness handicap (Dizziness Handicap Inventory) and visual analogue scale were compared according to the onset of vertigo symptoms. RESULTS: In VS patients, SOT showed decreased equilibrium score for all vestibular function related conditions, condition (C) 5 and 6, and composite (COMP) score. COMP scores were not correlated with visual analogue scale or Dizziness Handicap Inventory scores. Acute onset group included six patients and insidious onset group, 12 patients. Equilibrium scores for C5 and C6, and COMP scores were lower for insidious onset group, but the difference was not statistically significant. CONCLUSION: Our findings confirmed postural instability is prevalent in VS patients. SOT parameters did not differ significantly between acute onset and insidious onset groups, but increased tumor size and canal weakness were noted in the insidious onset group. Clinicians should consider that postural instability is likely present even in patients who do not complain of acute vertigo, and appropriate counseling should be discussed with the patients.

Reliability of Posturographic Parameters Assessing Standing Ability in Different Positions and Walking Activity in Healthy Participants / 中国康复理论与实践

@#Objective In the recovery process of stroke patients, the ability of maintaining standing and sitting position might have a great effect on the improvement of activity of daily living. There are few the methods which evaluate quantitatively and effectively the ability of position control ability in clinical practice. The aim of the study is to quantitatively evaluate the reliability of posturographic parameters based on the center of pelvis in different standing positions and walking activity.Methods From May to June, 2018, Seventy-nine healthy participants were enrolled. They were evaluated with iReGo, a walking assisstant robot, in three conditions: normal standing position, left/right standing position and walking 10 meters at an appropriate speed. The computer calculated the posturographic parameters automatically. The participants completed their second test one day after the first one.Results During normal standing position, the intra-class correlation coefficients (ICC) of average sway in coronal plane, average sway in sagittal plane, path length, and covered area were more than 0.70. During left standing position, ICC of all the above parameters were more than 0.70. During right standing position, ICC of all the above parameters were more than 0.49. When walking 10 meters at an appropriate speed, ICC of path length and covered area were more than 0.75. Comparing different standing positions, the normal standing position was more stable than the left/right standing position, and there was no difference between the left and the right standing positions.Conclusion Posturographic parameters based on the center of pelvis might be a reliable way to assess the position control ability in different standing positions and walking process.

Reliability and minimal detectable change of between-limb synchronization, weight-bearing symmetry, and amplitude of postural sway in individuals with stroke

Abstract Introduction: Recently, variables related to between-limb synchronization of the centers of pressure (COP) have been proposed as measures of postural control in post-stroke patients. Although it is crucial in verifying their potential clinical use, the reliability of these variables is unknown. The aim of this work was to determine the reliability and minimal detectable change (MDC) of the peak of synchronization (ρmax) in the anteroposterior (AP) and mediolateral (ML) directions, the time lag for the peak (ρmaxlag), synchronization at lag zero (ρ0), weight-bearing symmetry, and amplitude of postural sway, measured as the root mean square (RMS) values of the COP displacements in both directions (AP and ML COP displacement). Methods COP data of 16 participants with stroke were collected at quiet standing with two force plates at two sessions separated by 2 to 7 days. The procedure was repeated three times in each session. The within and between sessions reliability was determined by the intraclass correlation coefficient (ICC), and the MDC was obtained from the ICC between sessions. Results The variables ρmaxlag in the AP and ML directions, as well as ρ0 in the AP direction, exhibited poor within session reliability (ICC ≤ 0.4). The findings revealed excellent within and between sessions reliability (ICC ≥ 0.89) for weight-bearing symmetry and the RMS displacement in the AP direction, with MDC values of 5% and 2.07 mm, respectively. The remaining variables exhibited moderate reliability. Conclusion Weight-bearing symmetry and AP COP displacement can be considered reliable variables for use in clinical practice.

Hearing performance as a predictor of postural recovery in cochlear implant users / Desempenho auditivo como preditor de recuperação postural em usuários de implante coclear

Abstract Objective This study aimed to evaluate if hearing performance is a predictor of postural control in cochlear implant (CI) users at least six months after surgery. Methods Cross-sectional study including (CI) recipients with post-lingual deafness and controls who were divided into the following groups: nine CI users with good hearing performance (G+), five CI users with poor hearing performance (G−), and seven controls (CG). For each patient, computerized dynamic posturography (CDP) tests, a sensory organization test (SOT), and an adaptation test (ADT) were applied as dual task performance, with first test (FT) and re-test (RT) on the same day, including a 40–60 min interval between them to evaluate the short-term learning ability on postural recovery strategies. The results of the groups were compared. Results Comparing the dual task performance on CDP and the weighted average between all test conditions, the G+ group showed better performance on RT in SOT4, SOT5, SOT6, and CS, which was not observed for G− and CG. The G− group had significantly lower levels of short-term learning ability than the other two groups in SOT5 (p = 0.021), SOT6 (p = 0.025), and CS (p = 0.031). Conclusion The CI users with good hearing performance had a higher index of postural recovery when compared to CI users with poor hearing performance.

Resumo Objetivo O presente estudo teve por objetivo avaliar se o desempenho auditivo é preditor de controle postural em usuários de IC pelo menos seis meses após a cirurgia. Método Estudo transversal que consistiu em recipientes de implante coclear (IC) com surdez pós-lingual e controles, que foram divididos nos seguintes grupos: nove usuários de IC com bom desempenho auditivo (G+), cinco usuários de usuários de IC com desempenho auditivo insatisfatório (G-) e sete controles (GC). Aplicamos os testes de posturografia dinâmica computadorizada (PDC), de organização sensitiva (TOS) e de adaptação (TAd) como desempenho de dupla tarefa, primeiro teste (PT) e reteste (RT) no mesmo dia, com intervalo de 40-60 minutos entre testes, com o objetivo de avaliar a capacidade de aprendizado em curto prazo nas estratégias de recuperação postural. Comparamos os resultados dos testes. Resultados Na comparação do desempenho de dupla tarefa no teste PDC e a média ponderal entre todas as condições de teste, o grupo G+ demonstrou melhor desempenho no RT nos TOS4, TOS5, TOS6 e EC, o que não foi observado para os grupos G- e GC. O grupo G- obteve níveis significantemente mais baixos de capacidade de aprendizado em curto prazo vs. outros dois grupos no TOS5 (p = 0,021), TOS6 (p = 0,025) e EC (p = 0,031). Conclusão Usuários de IC com bom desempenho auditivo tiveram índice melhor de recuperação postural, quando comparados com usuários de IC com desempenho auditivo insatisfatório.

Role of Static Posturography in Fatigue Assessment due to Flight TasksLoad / 现代生物医学进展

Objective:To explore the role of static posturography in the assessment of fatigue due to flight tasks.Methods:Thirtymale college students were asked to perform simulated flight tasks consecutively forfour hours.Meanwhile their statie posturography and tasks performance would be repeatedly measured during the task-load at end of every hour.Based on the changed significantly parameters,the static balance index would be built by principle component analysis.Then its correlation with task-load level would be further analyzed by curve estimation.Results:Static postural control declined significantly under effect of simulated flight tasks.With task load sustaining,static balance index increased significantly and correlated linearly with duration of task load (R2=0.949).Besides,there was quadratic relationship between the change of multi-tasks performance and duration of task load (R2=0.968).And correlation of multi-tasks performance with static standing balance level also had been proved to be quadratic (R2=0.976).Conclusions:Static posturography correlated linearly with flight task-load level,which could reflect fatigue level caused by task load.

Balance Assessment in Subacute Stroke Patients Using the Balance Control Trainer (BalPro)

OBJECTIVE: To demonstrate the efficacy of the balance control trainer (BCT), developed for training patients with balance problems, as a balance assessment tool in subacute stroke patients. METHODS: A prospective cross-sectional study was carried out on 38 subacute stroke patients in their first episode of a stroke, and having the ability to maintain a standing position without aid for at least 5 minutes. Patients were assessed using the BCT (BalPro) 43.7±35.7 days after stroke. The balance was assessed using the Berg Balance Scale (BBS), the Timed Up and Go Test (TUG), a 10-meter walking test (10mWT), a 6-minute walking test (6MWT), and the Korean version of the Modified Barthel Index. The correlation and validity between the BCT and various balance assessments were analyzed. RESULTS: Statistically significant linear correlations were observed between the BCT score and the BBS (r=0.698, p<0.001). A moderate to excellent correlation was seen between the BCT score and 11 of the 14 BBS items. The BCT scores and other secondary outcome parameters (6MWT r=0.392, p=0.048; TUG r=–0.471, p=0.006; 10mWT r=–0.437, p=0.012) had a moderate correlation. CONCLUSION: Balance control training using the BCT (BalPro) showed significant statistical correlation with the BBS, and could therefore be a useful additional balance assessment tool in subacute stroke patients.

Postural sway in diabetic peripheral neuropathy among Indian elderly.

Background & objectives: Diabetic peripheral neuropathy (DPN) is a major complication of type 2 diabetes and have long term complications on the postural control of the affected population. The objectives of this study were to evaluate postural stability in patients with DPN and to examine correlation of Michigan Neuropathy Screening Instrument (MNSI) with duration of diabetes, age and postural stability measures. Methods: Participants were included if they had clinical neuropathy which was defined by MNSI. Sixty one patients gave their consent to participate in the study and were evaluated on posturography for postural stability measures in four conditions. Repeated measures of analysis of variance (RANOVA) was used to analyze the changes in postural stability measures in different conditions. Results: An increase in mean value of postural stability measures was observed for velocity moment 20.4±1.3, 24.3±2.2, 42.3±20.7, 59±43.03, mediolateral displacement 0.21±0.10, 0.22±0.18, 0.03±0.11, 0.34±0.18, and anteroposterior displacement 0.39 ± 0.09, 0.45±0.12, 0.47±0.13, 0.51±0.20 from EO to EC, EOF, and ECF, respectively. There was a significant difference (P<0.05) in participants with DPN, with greater sway amplitude on firm and foam surface in all the conditions. Moderate correlation of MNSI with age (r=0.43) and postural stability measures were also observed. Interpretation & conclusions: Evaluation of postural stability in Indian DPN population suggests balance impairments on either firm and foam surfaces, with greater likelihood of fall being on foam or deformable surfaces among elderly adults with neuropathy (CTRI/2011/07/001884).

Dynamic Posturography of Injured Lower Limb in Postural Evoked Response / 法医学杂志

Objective To analyze the balance function of injured lower lim b by dynam ic posturography. Methods Using the dynam ic posturography instrum ent, the postural evoked responses of sixty-two norm al people and two hundred and fifty-eight people with injured lower lim b bones and joints were detected. The test was included sensory organization test(SO T) and adaption test(ADT).The results of two groups were com pared by t test. Results Com pared with the norm al people, the im paired people had significant statistical differences in balance scores of SO T3-SO T6 and proportion score of dynam ic proprioception (P<0.05). There was no obvious decrease in ADT. Conclusion The balance function of injured lower lim b significantly decreases.

Diagnostic value of computerized dynamic posturography in the assessment of peripheral vestibular disorders

@#<p style="text-align: justify;"><strong>OBJECTIVES:</strong> This study aims to determine the sensitivity, specificity, positive predictive value and negative  predictive  value  of  Computerized  Dynamic  Posturography  (CDP)  in  properly  labeling patients with peripheral vestibular disorders by Videonystagmography (VNG) as having vestibular dysfunction.<br /><strong>METHODS:</strong><br /><strong>Design:</strong> Case - Control Study<br /><strong>Setting:</strong> Tertiary Private Hospital<br /><strong>Subjects:</strong> Twenty-three (23) patients aged 18 and above with no history of hypertension or cardiovascular disease and no intake of anti-vertigo medications for at least 48 hours prior to testing and with complete VNG and CDP results obtained on the same day or at least  two  days  apart  were  included  in  the  study. Cases were defined as those  diagnosed with a peripheral  vestibular  disorder  by VNG  while  controls  were  defined as those with  normal VNG results.  Sensitivity, specificity, positive predictive value and negative  predictive value of CDP in labeling those with peripheral vestibular disorders as vestibular were determined using VNG as gold standard.<br /><strong>RESULTS:</strong> There were 11 cases  (4  males, 7 females) and 12 controls (8  males,  4  females).  Using VNG  as  the  gold  standard  for  diagnosing  peripheral  vestibular  disorders,  CDP  had  a  sensitivity of 45.45% and specificity of 66.67% with Positive Predictive Value(PPV) of 55.56% and Negative Predictive Value(NPV) of 57.14%  in  assessing  peripheral vestibular disorders among the adults tested.  Interestingly, 33.33% of patients with normal VNG may actually have had a vestibular dysfunction that could be detected by CDP.<br /><strong>CONCLUSION:</strong> Prospective studies with larger sample sizes utilizing VNG and CDP are recommended in order to verify our findings.</p>

Body Sway as a Possible Indicator of Fatigue in Clerical Workers

BACKGROUND: Fatigue has a strong impact on workers' performance and safety, but expedient methods for assessing fatigue on the job are not yet available. Studies discuss posturography as an indicator of fatigue, but further evidence for its use in the workplace is needed. The purpose of the study is to examine whether posturography is a suitable indicator of fatigue in clerical workers. METHODS: Thirty-six employees (O 34.8 years, standard deviation = 12.5) participated in postural tasks (eyes open, eyes closed, arm swinging, and dual task) in the morning and afternoon. Position of their center of pressure (COP) was registered using a Nintendo Wii Balance Board and commercial software. From registered COP time series, we calculated the following parameters: path length (mm), velocity (mm/s), anterior-posterior variance (mm), mediolateral variance (mm), and confidence area (mm2). These parameters were reduced to two orthogonal factors in a factor analysis with varimax rotation. RESULTS: Statistical analysis of the first factor (path length and velocity) showed a significant effect of time of day: COP moved along a shorter path at a lower velocity in the afternoon compared with that in the morning. There also was a significant effect of task, but no significant interaction. CONCLUSION: Data suggest that postural stability of clerical workers was comparable in the morning and afternoon, but COP movement was greater in the morning. Within the framework of dynamic systems theory, this could indicate that the postural system explored the state space in more detail, and thus was more ready to respond to unexpected perturbations in the morning.

Robust evaluation of time since awakening using force platform posturography

INTRODUCTION: Sleepiness is responsible for a considerable proportion of traffic accidents. It is thus an important traffic safety issue to find a robust, objective and practical way to estimate the amount of time a person has been awake. To attempt to meet this goal, we investigated the relationship between sleepiness and posture control. METHODS: Subjects were kept awake for 36 hours and posturographic data during quiet standing were collected every two hours by means of a force platform. The standing surface (rigid surface or foam surface) and visual (eyes open or eyes closed) conditions were manipulated. RESULTS: In the more challenging conditions (with foam surface and/or eyes closed), the body sway variables derived from the center of the pressure measurement increased significantly when time since awakening became greater than 21 h in almost all subjects. CONCLUSION: Based on this result, we propose a practical protocol that could robustly assess whether time since awakening was greater than 21 h.

Posture Evoked Response Detecting in Normal Lower Limb Muscle and Its Influ-encing Factors / 法医学杂志

Objective To analyze the latency of posture evoked response of normal lower limb muscle in different stimulations and explore its influencing factors. Methods The normal lower limb was induced to produce postural evoked response by the dynamic posturography through two kinds of perturbations, the supporting surface rotation stimulation (Toes-up and Toes-down) and the horizontal perturbation stimulation (Forward and Backward). The latencies of tibialis anterior muscle and gastrocnemius muscle were recorded by surface electromyography acquisition system. The differences of the left and right limb, gen-der and height on the latency of postural evoked response were analyzed. Results (1) Under the Toes-up and Backward perturbation, the latency of tibialis anterior muscle was longer than gastrocnemius muscle;under the Toes-down and Forward perturbation, the latency of gastrocnemius muscle was longer than tib-ialis anterior muscle. (2) The latencies of left limb and right limb had no significant difference. (3) The la-tency in male was longer than that in female. (4) The latency gradually increased with the increase of height. Conclusion In the postural evoked response, different perturbations, gender and height have sig-nificant impacts on the latency of posture evoked response of lower limb muscle. However, the effect of height and gender should be not considered referring to the same individual.

Comparação entre testes de equilíbrio de campo e plataforma de força / Comparison between field balance tests and force platform

Vários testes de equilíbrio têm sido utilizados para identificar o controle postural e o risco de quedas em idosos. Entretanto, não se sabe quais testes refletem mais efetivamente a capacidade em manter o equilíbrio. O objetivo deste estudo foi comparar um conjunto de testes de campo de equilíbrio (TC) com os testes de posturografia em plataforma de força (PF) e verificar se esses testes são capazes de discriminar diferenças no equilíbrio entre jovens e idosos. Participaram do estudo 21 jovens (21,7 ± 2,0 anos) e 18 idosos (69,3 ± 7,0 anos) de ambos os gêneros. Os TC foram: escala de equilíbrio de Berg (BBS), escala de equilíbrio orientado pelo desempenho, (POMA), alcance funcional (AF) e levantar e caminhar cronometrado (TUGT). As variáveis analisadas na PF foram: amplitude de deslocamento nas direções anteroposterior (AMP-AP) e médio-lateral (AMP-ML) e trajetória do centro de pressão (TRAJ-CP). Os sujeitos foram avaliados em cinco condições durante 60s cada. Uma ANOVA one-way foi aplicada para determinar diferenças nos testes de equilíbrio entre grupos (jovens x idosos). Além disso, o teste de correlação de Spearman foi aplicado para identificar a associação entre os TC e PF. Os TC foram capazes de diferenciar jovens de idosos (p < 0,05). Os testes na PF também diferenciaram os grupos, exceto na AMP-AP em duas condições. As correlações indicaram que os testes BBS (r = - 0,43 ± 0,04) e TUGT (r = 0,45 ± 0,10) se correlacionaram com maior número de variáveis da PF (p < 0,05) e devem ser preferidos quando a avaliação do equilíbrio for determinada. Outros testes são questionados quanto à sua capacidade de determinar adequadamente o equilíbrio.

Several balance tests have been used to identify postural control and the risk of falls in the elderly. However, it is not known which tests better reflect effectively the ability to maintain balance. The objective of this study was to compare a number of field tests (FT) designed to determine balance with stabilometric tests using force platforms (FP) to determine whether these tests are able to discriminate differences in balance between young and older adults. Twenty-one young (21.7±2.0 years) and 18 older adults (69.3±7.0 years) of both genders volunteered to participate in the study. The field tests were: Berg Balance Scale (BBS), Performance Oriented Mobility Assessment (POMA), Functional Reach (FR) and Timed Up and Go Test (TUGT). The variables analyzed in the FP were: center of pressure displacement in the antero-posterior (AMP-AP) and medio-lateral direction (AMP-ML) and total sway of the center of pressure (TRAJ-CP). The subjects were evaluated in five conditions of 60s each. One-way ANOVA was applied to determine differences in balance tests between groups (young x elderly). In addition, the Spearman correlation test was used to identify the correlation between FT and FP. The FTs were able to discriminate young from elderly (p < 0.05). The FP tests also discriminated groups, except for AMP-AP in two experimental conditions. The correlation coefficients indicated that the tests BBS (r =- 0:43 ± 0.04) and TUGT (r = 0.45 ± 0.10) showed the largest correlation with the FP tests (p < 0.05). Thus, these field tests should be preferred among the other balance tests. The results of the other tests are questionable since they seemed unable to discriminate the balance performance between young and elderly subjects.