Comparison of Postural Stubility and Auditory Short- Term Memory Taks Interference between Patients with Functional Ankle Instability and Healthy Individuals

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Maryam Hayati

2010-04-01

Full Text Available Objective: With increased recognition of the importance of conscious process and cognition activities in the stability and regulation of posture and also in line of probable adaptation in central nervous system in patients with functional ankle instability, this study was aimed to assess interference patterns between short–term memory task and postural stability tasks in functional ankle instability patients in comparison with healthy individuals. Materials & Methods: In this cross–sectional and case–control study, with dual–task paradigm fifteen functional ankle instability patients whom were selected simply and conveniently and fifteen healthy persons whom were matched with patients as control group were assessed and compared. Six steps of tests were performed for every case with two situation of balance Biodex system instability and three situation of auditory short–term memory task. Data were analyzed by repeated measurement ANOVA. Results: Finding showed that there was significant interference between postural task and cognitive task in both groups (P<0.05 , but there was no significant difference between interferences of two groups. Conclusion: Present study, certificated disruption in information processing in a peripheral musculoskeletal injury such as functional ankle instability. Application of training programs in order to facilitate central information processing in balance rehabilitation process of this patients and improved dual–task paradigms with different degrees of cognitive and postural tasks seems to be effective.

Individuals with chronic ankle instability exhibit dynamic postural stability deficits and altered unilateral landing biomechanics: A systematic review.

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Simpson, Jeffrey D; Stewart, Ethan M; Macias, David M; Chander, Harish; Knight, Adam C

2018-06-13

To evaluate the literature regarding unilateral landing biomechanics and dynamic postural stability in individuals with and without chronic ankle instability (CAI). Four online databases (PubMed, ScienceDirect, Scopus, and SportDiscus) were searched from the earliest records to 31 January 2018, as well as reference sections of related journal articles, to complete the systematic search. Studies investigating the influence of CAI on unilateral landing biomechanics and dynamic postural stability were systematically reviewed and evaluated. Twenty articles met the criteria and were included in the systematic review. Individuals with CAI were found to have deficits in dynamic postural stability on the affected limb with medium to large effect sizes and altered lower extremity kinematics, most notably in the ankle and knee, with medium to large effect sizes. Additionally, greater loading rates and peak ground reaction forces, in addition to reductions in ankle muscle activity were also found in individuals with CAI during unilateral jump-landing tasks. Individuals with CAI demonstrate dynamic postural stability deficits, lower extremity kinematic alterations, and reduced neuromuscular control during unilateral jump-landings. These are likely factors that contribute recurrent lateral ankle sprain injuries during dynamic activity in individuals with CAI. Copyright © 2018 Elsevier Ltd. All rights reserved.

Intensive Abdominal Drawing-In Maneuver After Unipedal Postural Stability in Nonathletes With Core Instability

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Lee, Nam G.; You, Joshua (Sung) H.; Kim, Tae H.; Choi, Bong S.

2015-01-01

Context: The exact neuromechanical nature and relative contribution of the abdominal drawing-in maneuver (ADIM) to postural instability warrants further investigation in uninjured and injured populations. Objective: To determine the effects of the ADIM on static core and unipedal postural stability in nonathletes with core instability. Design: Controlled laboratory study. Setting: University research laboratory. Patients or Other Participants: A total of 19 nonathletes (4 women: age = 22.3 ± 1.3 years, height = 164.0 ± 1.7 cm, mass = 56.0 ± 4.6 kg; 15 men: age = 24.6 ± 2.8 years, height = 172.6 ± 4.7 cm, mass = 66.8 ± 7.6 kg) with core instability. Intervention(s): Participants received ADIM training with visual feedback 20 minutes each day for 7 days each week over a 2-week period. Main Outcome Measures(s): Core instability was determined using a prone formal test and measured by a pressure biofeedback unit. Unipedal postural stability was determined by measuring the center-of-pressure sway and associated changes in the abdominal muscle-thickness ratios. Electromyographic activity was measured concurrently in the external oblique, erector spinae, gluteus medius, vastus medialis oblique, tibialis anterior, and medial gastrocnemius muscles. Results: All participants initially were unable to complete the formal test. However, after the 2-week ADIM training period, all participants were able to reduce the pressure biofeedback unit by a range of 4 to 10 mm Hg from an initial 70 mm Hg and maintain it at 60 to 66 mm Hg with minimal activation of the external oblique (t18 = 3.691, P = .002) and erector spinae (t18 = 2.823, P = .01) muscles. Monitoring of the pressure biofeedback unit and other muscle activations confirmed that the correct muscle contraction defining the ADIM was accomplished. This core stabilization was well maintained in the unipedal-stance position, as evidenced by a decrease in the center-of-pressure sway measures (t18 range, 3.953–5.775, P

The influence of aging and attentional demands on recovery from postural instability.

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Stelmach, G E; Zelaznik, H N; Lowe, D

1990-06-01

It is well known that the risk of a debilitating injury from a fall is much higher for elderly than for young individuals. In addition, it is well documented that healthy elderly subjects exhibit increased postural sway during normal stance tasks. In the present experiment, we explored the notion that control of minor postural instability in elderly subjects is attention demanding. Postural sway of eight elderly (mean age = 70.0 years) and eight young (mean age = 20.0 years) subjects was measured under two different secondary demands during stable and mildly unstable upright stance. There were two types of work loads. Either a cognitive (math task) or motor (hand-squeeze) task was performed during the second segment of a 50-second standing trial. The effect of these work loads on mean velocity, range, and variability of range of center of foot pressure was measured during the destabilizing activity of arm swinging and subsequent recovery period. Following seven seconds of 1 Hz arm-swinging activity, elderly subjects showed a marked increase in recovery time to normal stance when concurrently performing an arithmetic task. This result suggests that recovery from a posturally destabilizing activity, involving proprioceptive and vestibular information, places increased attentional demands on the postural support system of the elderly.

The effect of medication and the role of postural instability in different components of freezing of gait (FOG).

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Nantel, Julie; Bronte-Stewart, Helen

2014-04-01

Freezing of gait (FOG) is associated with gait asymmetry and arrhythmicity, cognitive impairment in Parkinson's disease (PD). However, the role of postural instability (PI) in and the effect of dopaminergic medication (meds) on FOG are unclear. We investigated the effect of meds on FOG using a validated metric, Stepping in Place (SIP) and the relationship between PI and FOG. We assessed static posturography (off meds), SIP, UPDRS-III (off/on meds) and the FOG-questionnaire (FOG-Q) in 15 freezers/15 non-freezers and 14 healthy controls. UPDRS-III, rigidity, tremor (P FOG-Q was correlated with CoP anteroposterior displacement and mediolateral VCoP (R = 0.42; R = 0.40, P FOG frequency and duration but not of gait asymmetry and arrhythmicity on meds suggests that both dopaminergic and non-dopaminergic networks contribute to FOG. The correlations between postural instability and FOG severity and SIP asymmetry on meds, suggest that as the disease progresses, postural instability interferes with gait symmetry and lead to on meds FOG and falls. Copyright © 2014 Elsevier Ltd. All rights reserved.

Association of postural instability with asymptomatic cerebrovascular damage and cognitive decline: the Japan Shimanami health promoting program study.

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Tabara, Yasuharu; Okada, Yoko; Ohara, Maya; Uetani, Eri; Kido, Tomoko; Ochi, Namiko; Nagai, Tokihisa; Igase, Michiya; Miki, Tetsuro; Matsuda, Fumihiko; Kohara, Katsuhiko

2015-01-01

Asymptomatic cerebral small-vessel disease (cSVD) in elderly individuals are potent risk factors for stroke. In addition to common clinical risk factors, postural instability has been postulated to be associated with cSVD in older frail patients. Here, we conducted a cross-sectional study to understand the possible link between postural instability and asymptomatic cSVD further, namely periventricular hyperintensity, lacunar infarction, and microbleeds, as well as cognitive function, in a middle-aged to elderly general population (n=1387). Postural instability was assessed based on one-leg standing time (OLST) and posturography findings. cSVD was evaluated by brain MRI. Mild cognitive impairment was assessed using a computer-based questionnaire, and carotid intima-media thickness as an index of atherosclerosis was measured via ultrasonography. Frequency of short OLST, in particular 2, 34.5%; microbleeds lesion: none, 10.1%; 1, 15.3%; >2, 30.0%; periventricular hyperintensity grade: 0, 5.7%; 1, 11.5%; >2, 23.7%). The association of short OLST with lacunar infarction and microbleeds but not periventricular hyperintensity remained significant even after adjustment for possible covariates (lacunar infarction, P=0.009; microbleeds, P=0.003; periventricular hyperintensity, P=0.601). In contrast, no significant association was found between posturographic parameters and cSVD, whereas these parameters were linearly associated with OLST. Short OLST was also significantly associated with reduced cognitive function independent of covariates, including cSVD (P=0.002). Postural instability was found to be associated with early pathological changes in the brain and functional decline, even in apparently healthy subjects. © 2014 American Heart Association, Inc.

Postural stability changes in the elderly with cataract simulation and refractive blur.

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Anand, Vijay; Buckley, John G; Scally, Andy; Elliott, David B

2003-11-01

To determine the influence of cataractous and refractive blur on postural stability and limb-load asymmetry (LLA) and to establish how postural stability changes with the spatial frequency and contrast of the visual stimulus. Thirteen elderly subjects (mean age, 70.76 +/- 4.14 [SD] years) with no history of falls and normal vision were recruited. Postural stability was determined as the root mean square [RMS] of the center of pressure (COP) signal in the anterior-posterior (A-P) and medial-lateral directions and LLA was determined as the ratio of the average body weight placed on the more-loaded limb to the less-loaded limb, recorded during a 30-second period. Data were collected under normal standing conditions and with somatosensory system input disrupted. Measurements were repeated with four visual targets with high (8 cyc/deg) or low (2 cyc/deg) spatial frequency and high (Weber contrast, approximately 95%) or low (Weber contrast, approximately 25%) contrast. Postural stability was measured under conditions of binocular refractive blur of 0, 1, 2, 4, and 8 D and with cataract simulation. The data were analyzed in a population-averaged linear model. The cataract simulation caused significant increases in postural instability equivalent to that caused by 8-D blur conditions, and its effect was greater when the input from the somatosensory system was disrupted. High spatial frequency targets increased postural instability. Refractive blur, cataract simulation, or eye closure had no effect on LLA. Findings indicate that cataractous and refractive blur increase postural instability, and show why the elderly, many of whom have poor vision along with musculoskeletal and central nervous system degeneration, are at greater risk of falling. Findings also highlight that changes in contrast sensitivity rather than resolution changes are responsible for increasing postural instability. Providing low spatial frequency information in certain environments may be useful in

Quantitative and clinical description of postural instability in women with breast cancer treated with taxane chemotherapy.

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Wampler, Meredith A; Topp, Kimberly S; Miaskowski, Christine; Byl, Nancy N; Rugo, Hope S; Hamel, Kate

2007-08-01

To describe the postural control of women who received taxane chemotherapy for treatment of breast cancer using quantitative and clinically feasible measures. Prospective descriptive study. University-based comprehensive cancer center. Twenty women who completed taxane treatment for breast cancer and 20 healthy controls participated in this study. Not applicable. Two quantitative measures of postural control were used, Sensory Organization Test (SOT) and center of pressure (COP) velocities. Two clinically feasible measures of postural control were used, the Fullerton Advanced Balance Scale (FABS) and Timed Up & Go (TUG) test. Compared with healthy controls, women with breast cancer had poorer postural control on all of the outcome measures. FABS and TUG scores correlated moderately with SOT and COP scores. After taxane chemotherapy, women with breast cancer show significantly increased postural instability compared with matched controls. Clinically feasible measures of postural control correlated with quantitative tests. These results suggest that these clinical measures may be useful to screen patients to determine who may benefit from rehabilitation.

Longer reaction time of the fibularis longus muscle and reduced postural control in basketball players with functional ankle instability: A pilot study.

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Méndez-Rebolledo, Guillermo; Guzmán-Muñoz, Eduardo; Gatica-Rojas, Valeska; Zbinden-Foncea, Hermann

2015-08-01

Motor control evaluation in subjects with functional ankle instability is questionable when both ankles of the same subject are compared (affected vs non-affected). To compare the postural control and reaction time of ankle muscles among: basketball players with FAI (instability group), basketball players without FAI (non-instability group) and healthy non-basketball-playing participants (control group). Case-control study. Laboratory. Instability (n = 10), non-instability (n = 10), and control groups (n = 11). Centre of pressure variables (area, velocity and sway) were measured with a force platform. Reaction time of ankle muscles was measured via electromyography. A one-way ANOVA demonstrated that there were significant differences between the instability and non-instability groups in the fibularis longus (p postural control and longer reaction time of the fibularis and tibialis anterior muscles. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Effect of Fatigue and Instability on Postural Control Parameters in Standing Posture in Healthy Adults and Patients with Chronic Low Back Pain

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Amir Hosein Kahlaee

2012-06-01

Full Text Available Background: This study aims at analyzing the effect of fatigue and instability on postural control parameters in both healthy people and patients with the chronic nonspecific low-back pain.Materials and Methods: In this non-experimental case-control study, oscillations of center of pressure were statistically analyzed in 16 healthy people and 15 patients with the chronic nonspecific low back pain. The analysis was conducted through two stages: before and after fatigue and under both stable and unstable surfaces. Results: Under the pre-fatigue, stable condition, there was not any difference between the two groups. Both fatigue and unstable surface changed our variables (sway area, range, velocity, frequency and total power of the signal. All the changes in variables were significant in the low-back pain group; while changes in the healthy group only covered the time-domain variables. The effect of instability was higher than that of fatigue. Conclusion: The postural control system for patients with low-back pain before fatigue and under stable condition, revealed sufficient competence to provide postural stability and its function cannot be differentiated from that in healthy people. Meanwhile, different mechanisms were used by these patients to confront stability challenging factors and further neural activity was required to counteract such factors.

Virtual Reality Telerehabilitation for Postural Instability in Parkinson’s Disease: A Multicenter, Single-Blind, Randomized, Controlled Trial

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Marialuisa Gandolfi

2017-01-01

Full Text Available Introduction. Telerehabilitation enables patients to access remote rehabilitation services for patient-physiotherapist videoconferencing in their own homes. Home-based virtual reality (VR balance training has been shown to reduce postural instability in patients with Parkinson’s disease (PD. The primary aim was to compare improvements in postural stability after remotely supervised in-home VR balance training and in-clinic sensory integration balance training (SIBT. Methods. In this multicenter study, 76 PD patients (modified Hoehn and Yahr stages 2.5–3 were randomly assigned to receive either in-home VR telerehabilitation (n=38 or in-clinic SIBT (n=38 in 21 sessions of 50 minutes each, 3 days/week for 7 consecutive weeks. VR telerehabilitation consisted of graded exergames using the Nintendo Wii Fit system; SIBT included exercises to improve postural stability. Patients were evaluated before treatment, after treatment, and at 1-month follow-up. Results. Analysis revealed significant between-group differences in improvement on the Berg Balance Scale for the VR telerehabilitation group (p=0.04 and significant Time × Group interactions in the Dynamic Gait Index (p=0.04 for the in-clinic group. Both groups showed differences in all outcome measures over time, except for fall frequency. Cost comparison yielded between-group differences in treatment and equipment costs. Conclusions. VR is a feasible alternative to in-clinic SIBT for reducing postural instability in PD patients having a caregiver.

Postural stability in the elderly during sensory perturbations and dual tasking: the influence of refractive blur.

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Anand, Vijay; Buckley, John G; Scally, Andy; Elliott, David B

2003-07-01

To determine the influence of refractive blur on postural stability during somatosensory and vestibular system perturbation and dual tasking. Fifteen healthy, elderly subjects (mean age, 71 +/- 5 years), who had no history of falls and had normal vision, were recruited. Postural stability during standing was assessed using a force platform, and was determined as the root mean square (RMS) of the center of pressure (COP) signal in the anterior-posterior (A-P) and medial-lateral directions collected over a 30-second period. Data were collected under normal standing conditions and with somatosensory and vestibular system perturbations. Measurements were repeated with an additional physical and/or cognitive task. Postural stability was measured under conditions of binocular refractive blur of 0, 1, 2, 4, and 8 D and with eyes closed. The data were analyzed with a population-averaged linear model. The greatest increases in postural instability were due to disruptions of the somatosensory and vestibular systems. Increasing refractive blur caused increasing postural instability, and its effect was greater when the input from the other sensory systems was disrupted. Performing an additional cognitive and physical task increased A-P RMS COP further. All these detrimental effects on postural stability were cumulative. The findings highlight the multifactorial nature of postural stability and indicate why the elderly, many of whom have poor vision and musculoskeletal and central nervous system degeneration, are at greater risk of falling. The findings also highlight that standing instability in both normal and perturbed conditions was significantly increased with refractive blur. Correcting visual impairment caused by uncorrected refractive error could be a useful intervention strategy to help prevent falls and fall-related injuries in the elderly.

Three-dimensional evaluation of postural stability in Parkinson's disease with mobile technology.

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Ozinga, Sarah J; Koop, Mandy Miller; Linder, Susan M; Machado, Andre G; Dey, Tanujit; Alberts, Jay L

2017-01-01

Postural instability is a hallmark of Parkinson's disease. Objective metrics to characterize postural stability are necessary for the development of treatment algorithms to aid in the clinical setting. The aim of this project was to validate a mobile device platform and resultant three-dimensional balance metric that characterizes postural stability. A mobile Application was developed, in which biomechanical data from inertial sensors within a mobile device were processed to characterize movement of center of mass in the medial-lateral, anterior-posterior and trunk rotation directions. Twenty-seven individuals with Parkinson's disease and 27 age-matched controls completed various balance tasks. A postural stability metric quantifying the amplitude (peak-to-peak) of sway acceleration in each movement direction was compared between groups. The peak-to-peak value in each direction for each individual with Parkinson's disease across all trials was expressed as a normalized value of the control data to identify individuals with severe postural instability, termed Cleveland Clinic-Postural Stability Index. In all conditions, the balance metric for peak-to-peak was significantly greater in Parkinson's disease compared to controls (p mobile device sensors, provides a rapid and systematic metric for quantifying postural stability in Parkinson's disease.

The effectiveness of foot orthotics in improving postural control in individuals with chronic ankle instability: a critically appraised topic.

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Gabriner, Michael L; Braun, Brittany A; Houston, Megan N; Hoch, Matthew C

2015-02-01

Chronic ankle instability (CAI) is a condition commonly experienced by physically active individuals. It has been suggested that foot orthotics may increase a CAI patient's postural control. For patients with CAI, is there evidence to suggest that an orthotic intervention will help improve postural control? The literature was searched for studies of level 2 evidence or higher that investigated the effects of foot orthotics on postural control in patients with CAI. The search of the literature produced 5 possible studies for inclusion; 2 studies met the inclusion criteria and were included. One randomized controlled trial and 1 outcomes study were included. Foot orthotics appear to be effective at improving postural control in patients with CAI. There is moderate evidence to support the use of foot orthotics in the treatment of CAI to help improve postural control. There is grade B evidence that foot orthotics help improve postural control in people with CAI. The Centre of Evidence Based Medicine recommends a grade of B for level 2 evidence with consistent findings.

Foam pad of appropriate thickness can improve diagnostic value of foam posturography in detecting postural instability.

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Liu, Bo; Leng, Yangming; Zhou, Renhong; Liu, Jingjing; Liu, Dongdong; Liu, Jia; Zhang, Su-Lin; Kong, Wei-Jia

2018-04-01

The present study investigated the effect of foam thickness on postural stability in patients with unilateral vestibular hypofunction (UVH) during foam posturography. Static and foam posturography were performed in 33 patients (UVH group) and 30 healthy subjects (control group) with eyes open (EO) and closed (EC) on firm surface and on 1-5 foam pad(s). Sway velocity (SV) of center of pressure, standing time before falling (STBF) and falls reaction were recorded and analyzed. (1) SVs had an increasing tendency in both groups as the foam pads were added under EO and EC conditions. (2) STBFs, only in UVH group with EC, decreased with foam thickness increasing. (3) Significant differences in SV were found between the control and UVH group with EO (except for standing on firm surface, on 1 and 2 foam pad(s)) and with EC (all surface conditions). (4) Receiver operating characteristic curve analysis showed that the SV could better reflect the difference in postural stability between the two groups while standing on the 4 foam pads with EC. Our study showed that diagnostic value of foam posturography in detecting postural instability might be enhanced by using foam pad of right thickness.

Impact of soft and hard insole density on postural stability in older adults.

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Losa Iglesias, Marta Elena; Becerro de Bengoa Vallejo, Ricardo; Palacios Peña, Domingo

2012-01-01

A significant predictor of falls in the elderly population is attributed to postural instability. Thus, it is important to identify and implement practical clinical interventions to enhance postural stability in older adults. Shoe insoles have been identified as a mechanism to enhance postural control, and our study aimed to evaluate the impact of 2 shoe insoles on static standing balance in healthy, older adults compared with standing posture while barefoot. We hypothesized that both hard and soft shoe insoles would decrease postural sway compared with the barefoot condition. Indeed, excursion distances and sway areas were reduced, and sway velocity was decreased when wearing insoles. The hard insole was also effective when visual feedback was removed, suggesting that the more rigid an insole, the greater potential reduction in fall risk. Thus, shoe insoles may be a cost-effective, clinical intervention that is easy to implement to reduce the risk of falling in the elderly population. Copyright © 2012 Mosby, Inc. All rights reserved.

Gait, posture and cognition in Parkinson's disease

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Barbosa, Alessandra Ferreira; Chen, Janini; Freitag, Fernanda; Valente, Debora; Souza, Carolina de Oliveira; Voos, Mariana Callil; Chien, Hsin Fen

2016-01-01

ABSTRACT Gait disorders and postural instability are the leading causes of falls and disability in Parkinson's disease (PD). Cognition plays an important role in postural control and may interfere with gait and posture assessment and treatment. It is important to recognize gait, posture and balance dysfunctions by choosing proper assessment tools for PD. Patients at higher risk of falling must be referred for rehabilitation as early as possible, because antiparkinsonian drugs and surgery do n...

Gait, posture and cognition in Parkinson's disease

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Alessandra Ferreira Barbosa

Full Text Available ABSTRACT Gait disorders and postural instability are the leading causes of falls and disability in Parkinson's disease (PD. Cognition plays an important role in postural control and may interfere with gait and posture assessment and treatment. It is important to recognize gait, posture and balance dysfunctions by choosing proper assessment tools for PD. Patients at higher risk of falling must be referred for rehabilitation as early as possible, because antiparkinsonian drugs and surgery do not improve gait and posture in PD.

Absence of rotation perception during warm water caloric irrigation in some seniors with postural instability

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Elodie eChiarovano

2016-01-01

Full Text Available Falls in seniors are a major public health problem. Falls lead to fear of falling, reduced mobility and decreased quality of life. Vestibular dysfunction is one of the fall risk factors. The relationship between objective measures of vestibular responses and age has been studied. However, the effects of age on vestibular perception during caloric stimulation have not been studied.Twenty senior subjects were included in the study separated in two groups: 10 seniors reporting postural instability (PI and exhibiting absence of vestibular perception when they tested with caloric stimulation and 10 sex and age-matched seniors with no such problems (controls. We assessed vestibular perception on a binary rating scale during the warm irrigation of the caloric test. The function of the various vestibular receptors was assessed using video-head impulse test (vHIT, caloric tests, and cervical and ocular VEMPs. The Equitest was used to evaluate balance. No horizontal canal dysfunction assessed using both caloric test and vHIT was detected in either group. No significant difference was detected between PI and control groups for the peak SPV of caloric induced ocular nystagmus or for the HVOR gain. All of the controls perceived rotation when the maximal SPV during warm irrigation was equal to or greater than 15°/s. None of the subjects in the PI group perceived rotation even while the peak SPV exceeded 15°/s, providing objective evidence of normal peripheral horizontal canal function. All of the PI group had abnormal Equitest results, particularly in the two last conditions.These investigations show for the first time that vestibular perception can be absent during a caloric test despite normal horizontal canal function. We call this dissociation vestibular neglect. Patients with poor vestibular perception may not be aware of postural perturbations and so will not correct for them. Thus, falls in the elderly may result, amongst other factors, from a

Changes in Postural Control After a Ball-Kicking Balance Exercise in Individuals With Chronic Ankle Instability

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Conceição, Josilene Souza; Schaefer de Araújo, Felipe Gustavo; Santos, Gilmar Moraes; Keighley, John

2016-01-01

Context:  Rehabilitation programs for patients with chronic ankle instability (CAI) generally involve balance-perturbation training (BPT). Anticipatory postural adjustments (APAs) and compensatory postural adjustments (CPAs) are the primary strategies used to maintain equilibrium during body perturbations. Little is known, however, about how APAs and CPAs are modified to promote better postural control for individuals with CAI after BPT. Objective:  To investigate the effect of BPT that involves kicking a ball on postural-control strategies in individuals with CAI. Design:  Randomized controlled clinical trial. Setting:  Laboratory. Patients or Other Participants:  We randomly assigned 44 volunteers with CAI to either a training group (TG; 11 women, 11 men; age = 24 ± 4 years, height = 173.0 ± 9.8 cm, mass = 72.64 ± 11.98 kg) or control group (CG; 11 women, 11 men; age = 22 ± 3 years, height = 171.0 ± 9.7 cm, mass = 70.00 ± 11.03 kg). Intervention(s):  The TG performed a single 30-minute training session that involved kicking a ball while standing on 1 foot. The CG received no intervention. Main Outcome Measure(s):  The primary outcome was the sum of the integrated electromyographic activity (∑∫EMG) of the lower extremity muscles in the supporting limb that were calculated during typical intervals for APAs and CPAs. A secondary outcome was center-of-pressure displacement during similar intervals. Results:  In the TG after training, the ∑∫EMG decreased in both dorsal and ventral muscles during compensatory adjustment (ie, the time interval that followed lower limb movement). During this interval, muscle activity (∑∫EMG) was less in the TG than in the CG. Consequently, center-of-pressure displacement increased during the task after training. Conclusions:  A single session of ball-kicking BPT promoted changes in postural-control strategies in individuals with CAI. These results should stimulate new and more comprehensive studies to

Ehlers-Danlos Syndrome, Hypermobility Type: Impact of Somatosensory Orthoses on Postural Control (A Pilot Study

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Emma G. Dupuy

2017-06-01

Full Text Available Elhers-Danlos syndrome (EDS is the clinical manifestation of connective tissue disorders, and comprises several clinical forms with no specific symptoms and selective medical examinations which result in a delay in diagnosis of about 10 years. The EDS hypermobility type (hEDS is characterized by generalized joint hypermobility, variable skin hyperextensibility and impaired proprioception. Since somatosensory processing and multisensory integration are crucial for both perception and action, we put forth the hypothesis that somatosensory deficits in hEDS patients may lead, among other clinical symptoms, to misperception of verticality and postural instability. Therefore, the purpose of this study was twofold: (i to assess the impact of somatosensory deficit on subjective visual vertical (SVV and postural stability; and (ii to quantify the effect of wearing somatosensory orthoses (i.e., compressive garments and insoles on postural stability. Six hEDS patients and six age- and gender-matched controls underwent a SVV (sitting, standing, lying on the right side evaluation and a postural control evaluation on a force platform (Synapsys, with or without visual information (eyes open (EO/eyes closed (EC. These two latter conditions performed either without orthoses, or with compression garments (CG, or insoles, or both. Results showed that patients did not exhibit a substantial perceived tilt of the visual vertical in the direction of the body tilt (Aubert effect as did the control subjects. Interestingly, such differential effects were only apparent when the rod was initially positioned to the left of the vertical axis (opposite the longitudinal body axis. In addition, patients showed greater postural instability (sway area than the controls. The removal of vision exacerbated this instability, especially in the mediolateral (ML direction. The wearing of orthoses improved postural stability, especially in the eyes-closed condition, with a particularly

Medio-lateral postural instability in subjects with tinnitus

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Zoi eKapoula

2011-05-01

Full Text Available Background: Many patients show modulation of tinnitus by gaze, jaw or neck movements, reflecting abnormal sensorimotor integration and interaction between various inputs. Postural control is based on multi-sensory integration (visual, vestibular, somatosensory, and oculomotor and indeed there is now evidence that posture can also be influenced by sound. Perhaps tinnitus influences posture similarly to external sound. This study examines the quality of postural performance in quiet stance in patients with modulated tinnitus.Methods: Twenty-three patients with highly modulated tinnitus were selected in the ENT service. Twelve reported exclusively or predominately left tinnitus, eight right and three bilateral. Eighteen control subjects were also tested. Subjects were asked to fixate a target at 40cm for 51s; posturography was performed with the platform (Technoconcept, 40Hz for both the eyes open and eyes closed conditions.Results: For both conditions, tinnitus subjects showed abnormally high lateral body sway (SDx. This was corroborated by fast Fourrier Transformation (FFTx and wavelet analysis. For patients with left tinnitus only, medio-lateral sway increased significantly when looking away from the center. Conclusions: Similarly to external sound stimulation, tinnitus could influence lateral sway by activating attention shift, and perhaps vestibular responses. Poor integration of sensorimotor signals is another possibility. Such abnormalities would be accentuated in left tinnitus because of the importance of the right cerebral cortex in processing both auditory-tinnitus and attention.

Use of Mobile Device Accelerometry to Enhance Evaluation of Postural Instability in Parkinson Disease.

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Ozinga, Sarah J; Linder, Susan M; Alberts, Jay L

2017-04-01

To determine the accuracy of inertial measurement unit data from a mobile device using the mobile device relative to posturography to quantify postural stability in individuals with Parkinson disease (PD). Criterion standard. Motor control laboratory at a clinic. A sample (N=28) of individuals with mild to moderate PD (n=14) and age-matched community-dwelling individuals without PD (n=14) completed the study. Not applicable. Center of mass (COM) acceleration measures were compared between the mobile device and the NeuroCom force platform to determine the accuracy of mobile device measurements during performance of the Sensory Organization Test (SOT). Analyses examined test-retest reliability of both systems and sensitivity of (1) the equilibrium score from the SOT and (2) COM acceleration measures from the force platform and mobile device to quantify postural stability across populations. Metrics of COM acceleration from inertial measurement unit data and the NeuroCom force platform were significantly correlated across balance conditions and groups (Pearson r range, .35 to .97). The SOT equilibrium scores failed to discriminate individuals with and without PD. However, the multiplanar measures of COM acceleration from the mobile device exhibited good to excellent reliability across SOT conditions and were able to discriminate individuals with and without PD in conditions with the greatest balance demands. Metrics employing medial-lateral movement produce a more sensitive outcome than the equilibrium score in identifying postural instability associated with PD. Overall, the output from the mobile device provides an accurate and reliable method of rapidly quantifying balance in individuals with PD. The portable and affordable nature of a mobile device with the application makes it ideally suited to use biomechanical data to aid in clinical decision making. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Postural orientation : Age-related changes in variability and time-to-boundary

NARCIS (Netherlands)

Van Wegen, E. E.H.; Van Emmerik, R. E.A.; Riccio, G. E.

2002-01-01

The relation between age-specific postural instability and the detection of stability boundaries was examined. Balance control was investigated under different visual conditions (eyes open/closed) and postural orientations·(forward/backward lean) while standing on a force platform. Dependent

Postural instability and gait are associated with severity and prognosis of Parkinson disease.

Science.gov (United States)

van der Heeden, Jorine F; Marinus, Johan; Martinez-Martin, Pablo; Rodriguez-Blazquez, Carmen; Geraedts, Victor J; van Hilten, Jacobus J

2016-06-14

Differences in disease progression in Parkinson disease (PD) have variously been attributed to 2 motor subtypes: tremor-dominant (TD) and postural instability and gait difficulty (PIGD)-dominant (PG). We evaluated the role of these phenotypic variants in severity and progression of nondopaminergic manifestations of PD and motor complications. Linear mixed models were applied to data from the Profiling Parkinson's disease (PROPARK) cohort (n = 396) to evaluate the effect of motor subtype on severity and progression of cognitive impairment (Scales for Outcomes in Parkinson's disease [SCOPA]-Cognition [SCOPA-COG]), depression (Hospital Anxiety and Depression Scale [HADS]), autonomic dysfunction (SCOPA-Autonomic [SCOPA-AUT]), excessive daytime sleepiness, psychotic symptoms (SCOPA-Psychiatric Complications [SCOPA-PC]), and motor complications. In first analyses, subtype as determined by the commonly used ratio of tremor over PIGD score was entered as a factor, whereas in second analyses separate tremor and PIGD scores were used. Results were verified in an independent cohort (Estudio Longitudinal de Pacientes con Enfermedad de Parkinson [ELEP]; n = 365). The first analyses showed that PG subtype patients had worse SCOPA-COG, HADS, SCOPA-AUT, SCOPA-PC, and motor complications scores, and exhibited faster progression on the SCOPA-COG. The second analyses showed that only higher PIGD scores were associated with worse scores for these variables; tremor score was not associated with severity or progression of any symptom. Analyses in the independent cohort yielded similar results. In contrast to PIGD, which consistently was associated with greater severity of nondopaminergic symptoms, there was no evidence of a benign effect of tremor. Our findings do not support the use of the TD subtype as a prognostic trait in PD. The results showed that severity of PIGD is a useful indicator of severity and prognosis in PD by itself. © 2016 American Academy of Neurology.

Postural stability and occlusal status among Japanese elderly.

Science.gov (United States)

Song-Yu, Xuan; Rodis, Omar M M; Ogata, Sagiri; Can-Hu, Jin; Nishimura, Michiko; Matsumura, Seishi

2012-06-01

There are still no data available on the relationship between postural stability and occlusal status among the elderly. To examine relationships between postural stability and occlusal status through a cohort study among elderly Japanese. Oral examination, occlusal status, postural stability and a questionnaire were conducted and given to 87 community-dwelling Japanese at enrolment. The average occlusal pressure of the female group was statistically higher than the male group while average occlusal pressure and postural stability length were lesser in the group with more remaining teeth. Postural stability area and number of remaining teeth showed statistically significant correlations. Postural stability length was lesser in the group with strong occlusal force. Furthermore, the number of decayed teeth was fewer in the good hygiene group. This study identified a close relationship between occlusal status and postural stability of Japanese older individuals. Occlusal hypofunction was observed more in those with occlusal problems, and a decrease in their occlusal functions resulted in postural instability. © 2011 The Gerodontology Society and John Wiley & Sons A/S.

Postural control assessment in students with normal hearing and sensorineural hearing loss.

Science.gov (United States)

Melo, Renato de Souza; Lemos, Andrea; Macky, Carla Fabiana da Silva Toscano; Raposo, Maria Cristina Falcão; Ferraz, Karla Mônica

2015-01-01

Children with sensorineural hearing loss can present with instabilities in postural control, possibly as a consequence of hypoactivity of their vestibular system due to internal ear injury. To assess postural control stability in students with normal hearing (i.e., listeners) and with sensorineural hearing loss, and to compare data between groups, considering gender and age. This cross-sectional study evaluated the postural control of 96 students, 48 listeners and 48 with sensorineural hearing loss, aged between 7 and 18 years, of both genders, through the Balance Error Scoring Systems scale. This tool assesses postural control in two sensory conditions: stable surface and unstable surface. For statistical data analysis between groups, the Wilcoxon test for paired samples was used. Students with hearing loss showed more instability in postural control than those with normal hearing, with significant differences between groups (stable surface, unstable surface) (ppostural control compared to normal hearing students of the same gender and age. Copyright © 2014 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Kinematics in newly walking toddlers does not depend upon postural stability

NARCIS (Netherlands)

Ivanenko, Yuri P; Dominici, Nadia; Cappellini, Germana; Lacquaniti, Francesco

When a toddler starts to walk without support, gait kinematics and electromyographic (EMG) activity differ from those of older children and the body displays considerable oscillations due to poor equilibrium. Postural instability clearly affects motor patterns in adults, but does instability explain

Postural stability in patients with decompression sickness evaluated by means of Quantitative Romberg testing

DEFF Research Database (Denmark)

Hedetoft, Morten; Hyldegaard, Ole

2015-01-01

obtained with the Quantitative Romberg test were observed in the group of DCS with vertigo relative to DCS without vertigo and healthy controls. A stepwise improvement in postural instability for DCS patients with vertigo was found following HBO2 therapy. After three treatments of HBO2, postural stability...... was found to be within the normal range of healthy controls. CONCLUSIONS: The Quantitative Romberg test offers the the clinician a fast, reliable and objective set of parametrical data to document postural instability in patients with either confirmed or suspected DCS.......OBJECTIVE: The present study was designed to retrospectively evaluate the use of quantitative Romberg's testing on postural stability during the course of hyperbaric oxygen (HBO2) therapy in patients presenting with decompression sickness (DCS). METHODS: The Quantitative Romberg test was used...

Postural steadiness and ankle force variability in peripheral neuropathy

Science.gov (United States)

Paxton, Roger J.; Feldman-Kothe, Caitlin; Trabert, Megan K.; Hitchcock, Leah N.; Reiser, Raoul F.; Tracy, Brian L.

2015-01-01

Introduction The purpose was to determine the effect of peripheral neuropathy (PN) on motor output variability for ankle muscles of older adults, and the relation between ankle motor variability and postural stability in PN patients. Methods Older adults with (O-PN) and without PN (O), and young adults (Y) underwent assessment of standing postural stability and ankle muscle force steadiness. Results O-PN displayed impaired ankle muscle force control and postural stability compared with O and Y groups. For O-PN, the amplitude of plantarflexor force fluctuations was moderately correlated with postural stability under no-vision conditions (r = 0.54, P = 0.01). Discussion The correlation of variations in ankle force with postural stability in PN suggests a contribution of ankle muscle dyscontrol to the postural instability that impacts physical function for older adults with PN. PMID:26284897

Correlation between Mechanical Properties of the Ankle Muscles and Postural Sway during the Menstrual Cycle.

Science.gov (United States)

Yim, JongEun; Petrofsky, Jerrold; Lee, Haneul

2018-03-01

Ankle and foot injuries are common among athletes and physically active individuals. The most common residual disability, ankle sprain, is characterized by instability along with postural sway. If the supporting structures around a joint become lax, posture stability and balance are also affected. Previous studies have examined muscle stiffness and elasticity and postural sway separately; however, the relationship between these factors is yet unknown. It is well known that the levels of sex hormones, especially estrogen, change in women over the phase of the menstrual cycle. Therefore, this study examined the relationship between the mechanical properties of tissue and balance activity using a non-invasive digital palpation device to determine if they undergo any changes over the menstrual cycle in young women. Sixteen young women with regular menstrual cycles completed the study. Tone, stiffness, and elasticity of the ankle muscles (lateral gastrocnemius, peroneus longus, and tibialis anterior) were measured using a non-invasive digital palpation device. Postural sway was recorded while the participants performed balance tasks during ovulation and menstruation. Significantly greater posture sway characteristics and ankle muscle elasticity were found during ovulation than during menstruation; lower tone and stiffness of the ankle muscles were observed at ovulation (p connective tissues. We therefore postulate that estrogen increases joint and muscle laxity and affects posture stability according to the phase of the menstrual cycle.

Postural Control and Gait Performance in the Diabetic Peripheral Neuropathy: A Systematic Review.

Science.gov (United States)

Mustapa, Amirah; Justine, Maria; Mohd Mustafah, Nadia; Jamil, Nursuriati; Manaf, Haidzir

2016-01-01

Purpose. The aim of this paper is to review the published studies on the characteristics of impairments in the postural control and gait performance in diabetic peripheral neuropathy (DPN). Methods. A review was performed by obtaining publication of all papers reporting on the postural control and gait performance in DPN from Google Scholar, Ovid, SAGE, Springerlink, Science Direct (SD), EBSCO Discovery Service, and Web of Science databases. The keywords used for searching were "postural control," "balance," "gait performance," "diabetes mellitus," and "diabetic peripheral neuropathy." Results. Total of 4,337 studies were hit in the search. 1,524 studies were screened on their titles and citations. Then, 79 studies were screened on their abstract. Only 38 studies were eligible to be selected: 17 studies on postural control and 21 studies on the gait performance. Most previous researches were found to have strong evidence of postural control impairments and noticeable gait deficits in DPN. Deterioration of somatosensory, visual, and vestibular systems with the pathologic condition of diabetes on cognitive impairment causes further instability of postural and gait performance in DPN. Conclusions. Postural instability and gait imbalance in DPN may contribute to high risk of fall incidence, especially in the geriatric population. Thus, further works are crucial to highlight this fact in the hospital based and community adults.

Mechanisms of postural control in alcoholic men and women: biomechanical analysis of musculoskeletal coordination during quiet standing.

Science.gov (United States)

Sullivan, Edith V; Rose, Jessica; Pfefferbaum, Adolf

2010-03-01

Excessive sway during quiet standing is a common sequela of chronic alcoholism even with prolonged sobriety. Whether alcoholic men and women who have remained abstinent from alcohol for weeks to months differ from each other in the degree of residual postural instability and biomechanical control mechanisms has not been directly tested. We used a force platform to characterize center-of-pressure biomechanical features of postural sway, with and without stabilizing conditions from touch, vision, and stance, in 34 alcoholic men, 15 alcoholic women, 22 control men, and 29 control women. Groups were matched in age (49.4 years), general intelligence, socioeconomic status, and handedness. Each alcoholic group was sober for an average of 75 days. Analysis of postural sway when using all 3 stabilizing conditions versus none revealed diagnosis and sex differences in ability to balance. Alcoholics had significantly longer sway paths, especially in the anterior-posterior direction, than controls when maintaining erect posture without balance aids. With stabilizing conditions the sway paths of all groups shortened significantly, especially those of alcoholic men, who demonstrated a 3.1-fold improvement in sway path difference between the easiest and most challenging conditions; the remaining 3 groups, each showed a approximately 2.4-fold improvement. Application of a mechanical model to partition sway paths into open-loop and closed-loop postural control systems revealed that the sway paths of the alcoholic men but not alcoholic women were characterized by greater short-term (open-loop) diffusion coefficients without aids, often associated with muscle stiffening response. With stabilizing factors, all 4 groups showed similar long-term (closed loop) postural control. Correlations between cognitive abilities and closed-loop sway indices were more robust in alcoholic men than alcoholic women. Reduction in sway and closed-loop activity during quiet standing with stabilizing

The Interaction between Visual and Proprioception Information for Dynamic Postural Control in Healthy Individuals

Directory of Open Access Journals (Sweden)

yasin hoseini

2017-06-01

Conclusion: the posture is controled mostly by the motion in the knee joint rather than the hip or ankle joints. It is recommended to enhance the knee extensors to prevent falling in people with high risk of postural instability.

Changes in postural control in patients with Parkinson's disease: a posturographic study.

Science.gov (United States)

Doná, F; Aquino, C C; Gazzola, J M; Borges, V; Silva, S M C A; Ganança, F F; Caovilla, H H; Ferraz, H B

2016-09-01

Postural instability is one of the most disabling features in Parkinson's disease (PD), and often leads to falls that reduce mobility and functional capacity. The objectives of this study were to analyse the limit of stability (LOS) and influence of the manipulation of visual, somatosensorial and visual-vestibular information on postural control in patients with PD and healthy subjects. Cross-sectional. Movement Disorders Unit, university setting. Eighty-two subjects aged between 37 and 83 years: 41 with Parkinson's disease in the 'on' state and 41 healthy subjects with no neurological disorders. Both groups were matched in terms of sex and age. Unified Parkinson's Disease Rating Scale (UPDRS)-motor score, modified Hoehn and Yahr staging, Dynamic Gait Index (DGI) and posturography with integrated virtual reality. The parameters analysed by posturography were LOS area, area of body centre of pressure excursion and balance functional reserve in the standing position in 10 conditions (open and closed eyes, unstable surface with eyes closed, saccadic and optokinetic stimuli, and visual-vestibular interaction). The mean UPDRS motor score and DGI score were 27 [standard deviation (SD) 14] and 21 (SD 3), respectively. Thirteen participants scored between 0 and 19 points, indicating major risk of falls. Posturographic assessment showed that patients with PD had significantly lower LOS area and balance functional reserve values, and greater body sway area in all posturographic conditions compared with healthy subjects. Patients with PD have reduced LOS area and greater postural sway compared with healthy subjects. The deterioration in postural control was significantly associated with major risk of falls. Copyright © 2015 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

Does increased postural threat lead to more conscious control of posture?

Science.gov (United States)

Huffman, J L; Horslen, B C; Carpenter, M G; Adkin, A L

2009-11-01

Although it is well established that postural threat modifies postural control, little is known regarding the underlying mechanism(s) responsible for these changes. It is possible that changes in postural control under conditions of elevated postural threat result from a shift to a more conscious control of posture. The purpose of this study was to determine the influence of elevated postural threat on conscious control of posture and to determine the relationship between conscious control and postural control measures. Forty-eight healthy young adults stood on a force plate at two different surface heights: ground level (LOW) and 3.2-m above ground level (HIGH). Centre of pressure measures calculated in the anterior-posterior (AP) direction were mean position (AP-MP), root mean square (AP-RMS) and mean power frequency (AP-MPF). A modified state-specific version of the Movement Specific Reinvestment Scale was used to measure conscious motor processing (CMP) and movement self-consciousness (MSC). Balance confidence, fear of falling, perceived stability, and perceived and actual anxiety indicators were also collected. A significant effect of postural threat was found for movement reinvestment as participants reported more conscious control and a greater concern about their posture at the HIGH height. Significant correlations between CMP and MSC with AP-MP were observed as participants who consciously controlled and were more concerned for their posture leaned further away from the platform edge. It is possible that changes in movement reinvestment can influence specific aspects of posture (leaning) but other aspects may be immune to these changes (amplitude and frequency).

Postural Control and Gait Performance in the Diabetic Peripheral Neuropathy: A Systematic Review

Directory of Open Access Journals (Sweden)

Amirah Mustapa

2016-01-01

Full Text Available Purpose. The aim of this paper is to review the published studies on the characteristics of impairments in the postural control and gait performance in diabetic peripheral neuropathy (DPN. Methods. A review was performed by obtaining publication of all papers reporting on the postural control and gait performance in DPN from Google Scholar, Ovid, SAGE, Springerlink, Science Direct (SD, EBSCO Discovery Service, and Web of Science databases. The keywords used for searching were “postural control,” “balance,” “gait performance,” “diabetes mellitus,” and “diabetic peripheral neuropathy.” Results. Total of 4,337 studies were hit in the search. 1,524 studies were screened on their titles and citations. Then, 79 studies were screened on their abstract. Only 38 studies were eligible to be selected: 17 studies on postural control and 21 studies on the gait performance. Most previous researches were found to have strong evidence of postural control impairments and noticeable gait deficits in DPN. Deterioration of somatosensory, visual, and vestibular systems with the pathologic condition of diabetes on cognitive impairment causes further instability of postural and gait performance in DPN. Conclusions. Postural instability and gait imbalance in DPN may contribute to high risk of fall incidence, especially in the geriatric population. Thus, further works are crucial to highlight this fact in the hospital based and community adults.

Measuring postural control during mini-squat posture in men with early knee osteoarthritis.

Science.gov (United States)

Petrella, M; Gramani-Say, K; Serrão, P R M S; Lessi, G C; Barela, J A; Carvalho, R P; Mattiello, S M

2017-04-01

Studies have suggested a compromised postural control in individuals with knee osteoarthritis (OA) evidenced by larger and faster displacement of center of pressure (COP). However, quantification of postural control in the mini-squat posture performed by patients with early knee OA and its relation to muscle strength and self-reported symptoms have not been investigated. The main aim of this cross-sectional, observational, controlled study was to determine whether postural control in the mini-squat posture differs between individuals with early knee OA and a control group (CG) and verify the relation among knee extensor torque (KET) and self-reported physical function, stiffness and pain. Twenty four individuals with knee OA grades I and II (OAG) (mean age: 52.35±5.00) and twenty subjects without knee injuries (CG) (mean age: 51.40±8.07) participated in this study. Participants were assessed in postural control through a force plate (Bertec Mod. USA), which provided information about the anterior-posterior (AP) and medial-lateral (ML) COP displacement during the mini-squat, in isometric, concentric and eccentric knee extensor torque (KET) (90°/s) through an isokinetic dynamometer (BiodexMulti-Joint System3, Biodex Medical Incorporation, New York, NY, USA), and in self-reported symptoms through the WOMAC questionnaire. The main outcomes measured were the AP and ML COP amplitude and velocity of displacement; isometric, concentric, and eccentric KET and self-reported physical function, stiffness and pain. No significant differences were found between groups for postural control (p>0.05). Significant lower eccentric KET (p=0.01) and higher scores for the WOMAC subscales of pain (p=postural instability and the need to include quadriceps muscle strengthening, especially by eccentric contractions. The relationship between the self-reported symptoms and a lower and slower COP displacement suggest that the postural control strategy during tasks with a semi-flexed knee

Postural changes versus balance control and falls in community-living older adults: a systematic review

Directory of Open Access Journals (Sweden)

Viviane Lemos Silva Fernandes

2018-06-01

Full Text Available Abstract Introduction: Since falls are considered to be a public health problem, it is important to identify whether postural changes over time contribute to the risk of falls in older adults. Objective: To investigate whether postural changes increase fall risk and/or postural imbalance in healthy, community-dwelling older adults. Methods: In April 2016, two reviewers independently searched the PubMed, Web of Science, SPORTDiscus, and CINAHL databases for studies in English published in the previous 10 years, using the following combined keywords: “posture” or (“kyphosis”,“lumbar lordosis”,“flexed posture”,“spinal curvature”,“spinal sagittal contour” AND “elderly” AND “fall”. Study quality was assessed according to the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology guidelines for observational studies. Results: The search retrieved 1,734 articles. Only observational studies that assessed posture, balance, and/or falls in older adults were considered eligible for review. The final sample included 17 articles: reliability and reproducibility of the instruments were not reported in five studies, while two studies offered a questionable description of the instruments used. Fourteen articles analyzed postural changes at the trunk level and three articles assessed them at the ankles and feet. Most studies found a positive association between postural changes and an increased risk for loss of balance and falls. Conclusion: Thoracic hyperkyphosis, loss of lumbar lordosis, and decreased plantar arch seem to contribute to greater postural instability, and thus to a higher risk of falls in community-living older adults.

The Effect of Wearing Different Types of Respirators on Postural Stability and Comfort

OpenAIRE

Farhang Akbar-Khanzadeh; Sandra M. Woolley; Kent Huang

2012-01-01

Respirators are commonly used to protect workers against workplace airborne contaminants, but this equipment may become a safety hazard by creating discomfort, disorientation and postural instability.Although postural stability is critical to workers, especially those working near moving objects or on surfaces where a loss of balance may become life threatening, little attention has been given to the effect of respirators on wearers’ postural stability. The purpose of this study was to examin...

Increased alertness, better than posture prioritization, explains dual-task performance in prosthesis users and controls under increasing postural and cognitive challenge.

Science.gov (United States)

Howard, Charla L; Perry, Bonnie; Chow, John W; Wallace, Chris; Stokic, Dobrivoje S

2017-11-01

Sensorimotor impairments after limb amputation impose a threat to stability. Commonly described strategies for maintaining stability are the posture first strategy (prioritization of balance) and posture second strategy (prioritization of concurrent tasks). The existence of these strategies was examined in 13 below-knee prosthesis users and 15 controls during dual-task standing under increasing postural and cognitive challenge by evaluating path length, 95% sway area, and anterior-posterior and medial-lateral amplitudes of the center of pressure. The subjects stood on two force platforms under usual (hard surface/eyes open) and difficult (soft surface/eyes closed) conditions, first alone and while performing a cognitive task without and then with instruction on cognitive prioritization. During standing alone, sway was not significantly different between groups. After adding the cognitive task without prioritization instruction, prosthesis users increased sway more under the dual-task than single-task standing (p ≤ 0.028) during both usual and difficult conditions, favoring the posture second strategy. Controls, however, reduced dual-task sway under a greater postural challenge (p ≤ 0.017), suggesting the posture first strategy. With prioritization of the cognitive task, sway was unchanged or reduced in prosthesis users, suggesting departure from the posture second strategy, whereas controls maintained the posture first strategy. Individual analysis of dual tasking revealed that greater postural demand in controls and greater cognitive challenge in prosthesis users led to both reduced sway and improved cognitive performance, suggesting cognitive-motor facilitation. Thus, activation of additional resources through increased alertness, rather than posture prioritization, may explain dual-task performance in both prosthesis users and controls under increasing postural and cognitive challenge.

Postural control and functional balance in individuals with diabetic peripheral neuropathy

Directory of Open Access Journals (Sweden)

Ana Claudia de Souza Fortaleza

2013-04-01

Full Text Available Diabetic Peripheral Neuropathy (DPN brings on reduced somatosensation, which can lead to changes in postural control. The objective of this study was to evaluate postural control in a standing position and in different conditions, as well as functional balance in individuals with DPN, make the correlation between the results obtained from the postural control assessment with the values from the functional balance test and compare the results obtained in the neuropathy group with those of the control group, checking for possible differences between the evaluation conditions of both groups. The study included 13 women with DPN (NG and 17 non-diabetic women (CG. Postural control assessment was performed by kinemetry in the following conditions: eyes opened (EO, eyes closed (EC, and semi-tandem (ST. The data was processed in MATLAB and the following variables were generated: mean amplitude of oscillation (MAO in the anterior-posterior (AP and medial-lateral (ML direction; and average speed of oscillation (ASO in AP and ML direction. Functional balance was assessed by the Timed Up and Go Test. There was significant difference between the groups (p≤0.005 in MAO-AP EO and EC, MAO-ML EC and ST, and ASO-ML ST. There were differences between the conditions EO and ST (p≤0.005 and EC and ST (p≤0.005 for the variables MAO-ML and ASO-ML with greater damage to the NG, which also had a lower functional balance (p=0.001. ML instability was positively correlated with functional imbalance. The results show a change in the postural control system in the DPN, which could lead these individuals to a higher risk for falls and functional impairment.

Assessment of Relationships Between Joint Motion Quality and Postural Control in Patients With Chronic Ankle Joint Instability.

Science.gov (United States)

Bączkowicz, Dawid; Falkowski, Krzysztof; Majorczyk, Edyta

2017-08-01

Study Design Controlled laboratory study, cross-sectional. Background Lateral ankle sprains are among the most common injuries encountered during athletic participation. Following the initial injury, there is an alarmingly high risk of reinjury and development of chronic ankle instability (CAI), which is dependent on a combination of factors, including sensorimotor deficits and changes in the biomechanical environment of the ankle joint. Objective To evaluate CAI-related disturbances in arthrokinematic motion quality and postural control and the relationships between them. Methods Sixty-three male subjects (31 with CAI and 32 healthy controls) were enrolled in the study. For arthrokinematic motion quality analysis, the vibroarthrographic signals were collected during ankle flexion/extension motion using an acceleration sensor and described by variability (variance of mean squares [VMS]), amplitude (mean of 4 maximal and 4 minimal values [R4]), and frequency (vibroarthrographic signal bands of 50 to 250 Hz [P1] and 250 to 450 Hz [P2]) parameters. Using the Biodex Balance System, single-leg dynamic balance was measured by overall, anteroposterior, and mediolateral stability indices. Results Values of vibroarthrographic parameters (VMS, R4, P1 and P2) were significantly higher in the CAI group than those in the control group (Pankle arthrokinematic motion and postural control were present. Therefore, physical therapy interventions focused on improving ankle neuromuscular control and arthrokinematic function are necessary in CAI patient care. J Orthop Sports Phys Ther 2017;47(8):570-577. Epub 4 Nov 2016. doi:10.2519/jospt.2017.6836.

Anticipatory and Compensatory Postural Adjustments in Response to External Lateral Shoulder Perturbations in Subjects with Parkinson's Disease.

Directory of Open Access Journals (Sweden)

Alexandre Kretzer E Castro de Azevedo

Full Text Available The purpose of this study was to investigate the anticipatory (APA and compensatory (CPA postural adjustments in individuals with Parkinson's disease (PD during lateral instability of posture. Twenty-six subjects (13 individuals with PD and 13 healthy matched controls were exposed to predictable lateral postural perturbations. The electromyographic (EMG activity of the lateral muscles and the displacement of the center of pressure (COP were recorded during four time intervals that are typical for postural adjustments, i.e., immediately before (APA1, APA2 and after (CPA1 and CPA2 the postural disturbances. The magnitude of the activity of the lateral muscles in the group with PD was lower only during the CPA time intervals and not during the anticipatory adjustments (APAs. Despite this finding, subjects with PD exhibit smaller COP excursions before and after the disturbance, probably due to lack of flexibility and proprioceptive impairments. The results of this study suggest that postural instability in subjects with PD can be partially explained by decreased postural sway, before and after perturbations, and reduced muscular activity after body disturbances. Our findings can motivate new studies to investigate therapeutic interventions that optimize the use of postural adjustment strategies in subjects with PD.

Neck Vibration Proprioceptive Postural Response Intact in Progressive Supranuclear Palsy unlike Idiopathic Parkinson’s Disease

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Stefan Kammermeier

2017-12-01

Full Text Available Progressive supranuclear palsy (PSP and late-stage idiopathic Parkinson’s disease (IPD are neurodegenerative movement disorders resulting in different postural instability and falling symptoms. IPD falls occur usually forward in late stage, whereas PSP falls happen in early stages, mostly backward, unprovoked, and with high morbidity. Postural responses to sensory anteroposterior tilt illusion by bilateral dorsal neck vibration were probed in both groups versus healthy controls on a static recording posture platform. Three distinct anteroposterior body mass excursion peaks (P1–P3 were observed. 18 IPD subjects exhibited well-known excessive response amplitudes, whereas 21 PSP subjects’ responses remained unaltered to 22 control subjects. Neither IPD nor PSP showed response latency deficits, despite brainstem degeneration especially in PSP. The observed response patterns suggest that PSP brainstem pathology might spare the involved proprioceptive pathways and implies viability of neck vibration for possible biofeedback and augmentation therapy in PSP postural instability.

Clinical working postures of bachelor of oral health students.

Science.gov (United States)

Horton, S J; Johnstone, C L; Hutchinson, C M W; Taylor, P A; Wade, K J

2011-09-01

To observe and describe the clinical working postures of final-year Bachelor of Oral Health (BOH) students. Pilot observational study. The University of Otago Faculty of Dentistry and School of Physiotherapy. Eight final-year BOH students voluntarily participated in this study, where postural data were collected using a digital video camera during a standard clinical treatment session. The postural data were analysed using 3D Match biomechanical software. Final-year BOH students who work in the seated position are exposed to neck flexion of greater than 35 degrees, together with trunk flexion greater than 20 degrees and bilateral elbow flexion greater than 90 degrees. The findings of this study agree with the findings of previous postural studies of dental professionals. Dental hygiene students, together with their clinical supervisors, need to be aware of the importance of good working posture early in their careers, and pay particular attention to the degree of neck flexion occurring for prolonged periods.

Postural ortostatisk takykardisyndrom

DEFF Research Database (Denmark)

Brinth, Louise; Pors, Kirsten; Mehlsen, Jesper

2014-01-01

Postural orthostatic tachycardia syndrome (POTS) is a heterogeneous condition of dysautonomia and suspected autoimmunity characterized by abnormal increments in heart rate upon assumption of the upright posture accompanied by symptoms of cerebral hypoperfusion and sympathoexcitation. An increase...... in heart rate equal to or greater than 30 bpm or to levels higher than 120 bpm during a head-up tilt test is the main diagnostic criterion. Management includes both non-pharmacological and pharmacological treatment focusing on stress management, volume expansion and heart rate control....

Posture and isokinetic shoulder strength in female water polo players

African Journals Online (AJOL)

Kathryn van Boom

pathological injuries, such as rotator cuff tendinitis, shoulder instability and shoulder ... and specific postural characteristics, which will be useful in future studies. ... concentric and eccentric IR and ER shoulder muscle strength in 15 club-level ...

White matter hyperintensities in Parkinson's disease: do they explain the disparity between the postural instability gait difficulty and tremor dominant subtypes?

Directory of Open Access Journals (Sweden)

Talia Herman

Full Text Available BACKGROUND: Brain white matter hyperintensities (WMHs commonly observed on brain imaging of older adults are associated with balance and gait impairment and have also been linked to cognitive deficits. Parkinson's disease (PD is traditionally sub-classified into the postural instability gait difficulty (PIGD sub-type, and the tremor dominant (TD sub-type. Considering the known association between WMHs and axial symptoms like gait disturbances and postural instability, one can hypothesize that WMHs might contribute to the disparate clinical sub-types of patients with PD. METHODS: 110 patients with PD underwent a clinical evaluation and a 3T MRI exam. Based on the Unified Parkinson Disease Rating Scale, the patients were classified into motor sub-types, i.e., TD or PIGD, and scores reflecting PIGD and TD symptoms were computed. We compared white matter burden using three previously validated methods: one using a semi-quantitative visual rating scale in specific brain regions and two automated methods. RESULTS: Overall, MRI data were obtained in 104 patients. The mean WMHs scores and the percent of subjects with lesions in specific brain regions were similar in the two subtypes, p = 0.678. The PIGD and the TD scores did not differ even when comparing patients with a relatively high burden of WMHs to patients with a relatively low burden. Across most of the brain regions, mild to moderate correlations between WMHs and age were found (r = 0.23 to 0.41; p<0.021. Conversely, no significant correlations were found between WMHs and the PIGD score or disease duration. In addition, depressive symptoms and cerebro-vascular risk factors were similar among the two subtypes. CONCLUSIONS: In contrast to what has been reported previously among older adults, the present study could not demonstrate any association between WMHs and the PIGD or TD motor sub-types in patients with PD.

Postural control and functional balance in individuals with diabetic peripheral neuropathy

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Ana Claudia de Souza Fortaleza

2013-03-01

Full Text Available DOI: http://dx.doi.org/10.5007/1980-0037.2013v15n3p305 Diabetic Peripheral Neuropathy (DPN brings on reduced somatosensation, which can lead to changes in postural control. The objective of this study was to evaluate postural control in a standing position and in different conditions, as well as functional balance in individuals with DPN, make the correlation between the results obtained from the postural control assessment with the values from the functional balance test and compare the results obtained in the neuropathy group with those of the control group, checking for possible differences between the evaluation conditions of both groups. The study included 13 women with DPN (NG and 17 non-diabetic women (CG. Postural control assessment was performed by kinemetry in the following conditions: eyes opened (EO, eyes closed (EC, and semi-tandem (ST. The data was processed in MATLAB and the following variables were generated: mean amplitude of oscillation (MAO in the anterior-posterior (AP and medial-lateral (ML direction; and average speed of oscillation (ASO in AP and ML direction. Functional balance was assessed by the Timed Up and Go Test. There was significant difference between the groups (p≤0.005 in MAO-AP EO and EC, MAO-ML EC and ST, and ASO-ML ST. There were differences between the conditions EO and ST (p≤0.005 and EC and ST (p≤0.005 for the variables MAO-ML and ASO-ML with greater damage to the NG, which also had a lower functional balance (p=0.001. ML instability was positively correlated with functional imbalance. The results show a change in the postural control system in the DPN, which could lead these individuals to a higher risk for falls and functional impairment.

Inefficient postural responses to unexpected slips during walking in older adults.

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Tang, P F; Woollacott, M H

1998-11-01

Slips account for a high percentage of falls and subsequent injuries in community-dwelling older adults but not in young adults. This phenomenon suggests that although active and healthy older adults preserve a mobility level comparable to that of young adults, these older adults may have difficulty generating efficient reactive postural responses when they slip. This study tested the hypothesis that active and healthy older adults use a less effective reactive balance strategy than young adults when experiencing an unexpected forward slip occurring at heel strike during walking. This less effective balance strategy would be manifested by slower and smaller postural responses, altered temporal and spatial organization of the postural responses, and greater upper trunk instability after the slip. Thirty-three young adults (age range=19-34 yrs, mean=25+/-4 yrs) and 32 community-dwelling older adults (age range=70-87 yrs, mean=74+/-14 yrs) participated. Subjects walked across a movable forceplate which simulated a forward slip at heel strike. Surface electromyography was recorded from bilateral leg, thigh, hip, and trunk muscles. Kinematic data were collected from the right (perturbed) side of the body. Although the predominant postural muscles and the activation sequence of these muscles were similar between the two age groups, the postural responses of older adults were of longer onset latencies, smaller magnitudes, and longer burst durations compared to young adults. Older adults also showed a longer coactivation duration for the ankle, knee, and trunk agonist/antagonist pairs on the perturbed side and for the knee agonist/antagonist pair on the nonperturbed side. Behaviorally, older adults became less stable after the slips. This was manifested by a higher incidence of being tripped (21 trials in older vs 5 trials in young adults) and a greater trunk hyperextension with respect to young adults. Large arm elevation was frequently used by older adults to assist in

Face Piercing (Body Art): Choosing Pleasure vs. Possible Pain and Posture Instability

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Matheron, Eric; Kapoula, Zoï

2011-01-01

Piercings (body art, i.e., with jewelry) are more and more widespread. They can induce various complications such as infections, allergies, headaches, and various skin, cartilage, or dental problems, and represent a public health problem. We draw attention to possible side effects resulting from face piercing complications observed on four young adults such as eye misalignment, decreased postural control efficiency, and non-specific chronic back pain with associated comorbidity. We found that the origin was pierced jewelry on the face. Removing the jewelry restored eye alignment, improved postural control, and alleviated back pain in a lasting way. We suggest that pierced facial jewelry can disturb somaesthetic signals driven by the trigeminal nerve, and thus interfere with central integration processes, notably in the cerebellum and the vestibular nucleus involved in postural control and eye alignment. Facial piercings could induce sensory–motor conflict, exacerbate, or precipitate a pre-existing undetermined conflict, which leads pain and complaints. These findings are significant for health; further investigations would be of interest. PMID:21960975

Postural control and head stability during natural gaze behaviour in 6- to 12-year-old children.

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Schärli, A M; van de Langenberg, R; Murer, K; Müller, R M

2013-06-01

We investigated how the influence of natural exploratory gaze behaviour on postural control develops from childhood into adulthood. In a cross-sectional design, we compared four age groups: 6-, 9-, 12-year-olds and young adults. Two experimental trials were performed: quiet stance with a fixed gaze (fixed) and quiet stance with natural exploratory gaze behaviour (exploratory). The latter was elicited by having participants watch an animated short film on a large screen in front of them. 3D head rotations in space and centre of pressure (COP) excursions on the ground plane were measured. Across conditions, both head rotation and COP displacement decreased with increasing age. Head movement was greater in the exploratory condition in all age groups. In all children-but not in adults-COP displacement was markedly greater in the exploratory condition. Bivariate correlations across groups showed highly significant positive correlations between COP displacement in ML direction and head rotation in yaw, roll, and pitch in both conditions. The regularity of COP displacements did not show a clear developmental trend, which indicates that COP dynamics were qualitatively similar across age groups. Together, the results suggest that the contribution of head movement to eye-head saccades decreases with age and that head instability-in part resulting from such gaze-related head movements-is an important limiting factor in children's postural control. The lack of head stabilisation might particularly affect children in everyday activities in which both postural control and visual exploration are required.

Postural control and central motor pathway involvement in type 2 ...

African Journals Online (AJOL)

Logistic regression analysis showed peripheral neuropathy as the main factor implicated in postural instability in these patients. However, significant correlation was found between MEP amplitude and MCT composite score in patients without peripheral neuropathy. Conclusion: Although type 2 diabetic patients had ...

Postural ortostatisk takykardi-syndrom

DEFF Research Database (Denmark)

Brinth, Louise; Pors, Kirsten; Mehlsen, Jesper

2015-01-01

Postural orthostatic tachycardia syndrome (POTS) is a heterogeneous condition of dysautonomia and suspected autoimmunity characterized by abnormal increments in heart rate upon assumption of the upright posture accompanied by symptoms of cerebral hypoperfusion and sympathoexcitation. An increase...... in heart rate equal to or greater than 30 bpm or to levels higher than 120 bpm during a head-up tilt test is the main diagnostic criterion. Management includes both non-pharmacological and pharmacological treatment focusing on stress management, volume expansion and heart rate control....

Relationship between static foot posture and foot mobility

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McPoil Thomas G

2011-01-01

Full Text Available Abstract Background It is not uncommon for a person's foot posture and/or mobility to be assessed during a clinical examination. The exact relationship, however, between static posture and mobility is not known. Objective The purpose of this study was to determine the degree of association between static foot posture and mobility. Method The static foot posture and foot mobility of 203 healthy individuals was assessed and then analyzed to determine if low arched or "pronated" feet are more mobile than high arched or "supinated" feet. Results The study demonstrated that those individuals with a lower standing dorsal arch height and/or a wider standing midfoot width had greater mobility in their foot. In addition, those individuals with higher Foot Posture Index (FPI values demonstrated greater mobility and those with lower FPI values demonstrated less mobility. Finally, the amount of foot mobility that an individual has can be predicted reasonably well using either a 3 or 4 variable linear regression model. Conclusions Because of the relationship between static foot posture and mobility, it is recommended that both be assessed as part of a comprehensive evaluation of a individual with foot problems.

An active balance board system with real-time control of stiffness and time-delay to assess mechanisms of postural stability.

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Cruise, Denise R; Chagdes, James R; Liddy, Joshua J; Rietdyk, Shirley; Haddad, Jeffrey M; Zelaznik, Howard N; Raman, Arvind

2017-07-26

Increased time-delay in the neuromuscular system caused by neurological disorders, concussions, or advancing age is an important factor contributing to balance loss (Chagdes et al., 2013, 2016a,b). We present the design and fabrication of an active balance board system that allows for a systematic study of stiffness and time-delay induced instabilities in standing posture. Although current commercial balance boards allow for variable stiffness, they do not allow for manipulation of time-delay. Having two controllable parameters can more accurately determine the cause of balance deficiencies, and allows us to induce instabilities even in healthy populations. An inverted pendulum model of human posture on such an active balance board predicts that reduced board rotational stiffness destabilizes upright posture through board tipping, and limit cycle oscillations about the upright position emerge as feedback time-delay is increased. We validate these two mechanisms of instability on the designed balance board, showing that rotational stiffness and board time-delay induced the predicted postural instabilities in healthy, young adults. Although current commercial balance boards utilize control of rotational stiffness, real-time control of both stiffness and time-delay on an active balance board is a novel and innovative manipulation to reveal balance deficiencies and potentially improve individualized balance training by targeting multiple dimensions contributing to standing balance. Copyright © 2017 Elsevier Ltd. All rights reserved.

Interactions between posture and locomotion: motor patterns in humans walking with bent posture versus erect posture.

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Grasso, R; Zago, M; Lacquaniti, F

2000-01-01

Human erect locomotion is unique among living primates. Evolution selected specific biomechanical features that make human locomotion mechanically efficient. These features are matched by the motor patterns generated in the CNS. What happens when humans walk with bent postures? Are normal motor patterns of erect locomotion maintained or completely reorganized? Five healthy volunteers walked straight and forward at different speeds in three different postures (regular, knee-flexed, and knee- and trunk-flexed) while their motion, ground reaction forces, and electromyographic (EMG) activity were recorded. The three postures imply large differences in the position of the center of body mass relative to the body segments. The elevation angles of the trunk, pelvis, and lower limb segments relative to the vertical in the sagittal plane, the ground reaction forces and the rectified EMGs were analyzed over the gait cycle. The waveforms of the elevation angles along the gait cycle remained essentially unchanged irrespective of the adopted postures. The first two harmonics of these kinematic waveforms explain >95% of their variance. The phase shift but not the amplitude ratio between the first harmonic of the elevation angle waveforms of adjacent pairs was affected systematically by changes in posture. Thigh, shank, and foot angles covaried close to a plane in all conditions, but the plane orientation was systematically different in bent versus erect locomotion. This was explained by the changes in the temporal coupling among the three segments. For walking speeds >1 m s(-1), the plane orientation of bent locomotion indicates a much lower mechanical efficiency relative to erect locomotion. Ground reaction forces differed prominently in bent versus erect posture displaying characteristics intermediate between those typical of walking and those of running. Mean EMG activity was greater in bent postures for all recorded muscles independent of the functional role. The waveforms

A new approach of the Star Excursion Balance Test to assess dynamic postural control in people complaining from chronic ankle instability.

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Pionnier, Raphaël; Découfour, Nicolas; Barbier, Franck; Popineau, Christophe; Simoneau-Buessinger, Emilie

2016-03-01

The purpose of this study was to quantitatively and qualitatively assess dynamic balance with accuracy in individuals with chronic ankle instability (CAI). To this aim, a motion capture system was used while participants performed the Star Excursion Balance Test (SEBT). Reached distances for the 8 points of the star were automatically computed, thereby excluding any dependence to the experimenter. In addition, new relevant variables were also computed, such as absolute time needed to reach each distance, lower limb ranges of motion during unipodal stance, as well as absolute error of pointing. Velocity of the center of pressure and range of variation of ground reaction forces have also been assessed during the unipodal phase of the SEBT thanks to force plates. CAI group exhibited smaller reached distances and greater absolute error of pointing than the control group (p<0.05). Moreover, the ranges of motion of lower limbs joints, the velocity of the center of pressure and the range of variation of the ground reaction forces were all significantly smaller in the CAI group (p<0.05). These reduced quantitative and qualitative performances highlighted a lower dynamic postural control. The limited body movements and accelerations during the unipodal stance in the CAI group could highlight a protective strategy. The present findings could help clinicians to better understand the motor strategies used by CAI patients during dynamic balance and may guide the rehabilitation process. Copyright © 2016 Elsevier B.V. All rights reserved.

Postural control and freezing of gait in Parkinson's disease.

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Schlenstedt, Christian; Muthuraman, Muthuraman; Witt, Karsten; Weisser, Burkhard; Fasano, Alfonso; Deuschl, Günther

2016-03-01

The relationship between freezing of gait (FOG) and postural instability in Parkinson's disease (PD) is unclear. We analyzed the impact of FOG on postural control. 31 PD patients with FOG (PD+FOG), 27 PD patients without FOG (PD-FOG) and 22 healthy control (HC) were assessed in the ON state. Postural control was measured with the Fullerton Advanced Balance (FAB) scale and with center of pressure (COP) analysis during quiet stance and maximal voluntary forward/backward leaning. The groups were balanced concerning age, disease duration and disease severity. PD+FOG performed significantly worse in the FAB scale (21.8 ± 5.8) compared to PD-FOG (25.6 ± 5.0) and HC (34.9 ± 2.4) (mean ± SD, p postural control asymmetry. PD+FOG have reduced postural control compared to PD-FOG and HC. Our results show a relationship between the anterior-posterior COP position during quiet stance and FOG. The COP shift towards posterior in PD+FOG leads to a restricted precondition to generate forward progression during gait initiation. This may contribute to the occurrence of FOG or might be a compensatory strategy to avoid forward falls. Copyright © 2015 Elsevier Ltd. All rights reserved.

Face piercing (body art: choosing pleasure vs. possible pain and posture instability

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Eric eMatheron

2011-09-01

Full Text Available Piercings (body art, i.e. with jewelry are more and more widespread. They can induce various complications such as infections, allergies, headaches, and various skin, cartilage, or dental problems which will lead to economic effects on health-care systems. We draw attention to other possible side effects resulting from face piercing complications such as eye misalignment, decreased postural control efficiency, and nonspecific chronic back pain. We found that the origin was pierced jewelry on the face. Removing the jewelry restored eye alignment, improved postural control, and alleviated back pain in a lasting way. This observation is important for health; further investigations would be of interest.

Effect of Symmetry Improvement in Weight Bearing on Postural Stability of Hemiparetic Patients

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Hossein Asghar-Hosseini

2008-07-01

Full Text Available Objective: Impaired postural control has been known as the main cause of fall in hemiparesis after stroke. Is Asymmetry of weight bearing on lower limb is one of the prominent characteristics of postural imbalance in these patients. The aim of this study was to evaluate the effect of symmetry improvement in weight bearing through therapeutic interventions on postural stability in hemiparetic patients. Materials & Methods: In this quasi – experimental study which 27 hemiparetic patients were selected through sample of convenience by simple method from men and women who were referred to neurology clinic of Hazrat-e-Rasool hospital. For postural assessment patients stood quietly with open eyes and close eyes on force plates. Primary assessments included evaluation of asymmetry index (AI, RMS COP displacement (Root Mean Square of Center of Pressure and RMS COP velocity in both frontal and sagital planes. Then a 10mm lift was inserted under the unaffected limb and primary assessments were repeated. Data were analyzed by repeated measure ANOVA test. Results: Simple main effect of lift on asymmetry index was significant (P<0/0001. There was no significant interaction between vision and lift. Simple main effect of lift on postural stability variables was also non significant (for RMS COP displacement in frontal and sagital planes P=0.186 and P=0.245, respectively and for RMS COP velocity P=0.259 and P=0.342 respectively. Conclusion: Inserting a lift can improve symmetry by shifting center of gravity to midline. Since symmetry improvement did not decrease postural instability, asymmetric weight bearing can not be the primary cause of postural instability and may not be the principal target of rehabilitation programs aiming at restoring standing balance after stroke.

The contribution of proprioceptive information to postural control in elderly and patients with Parkinson's disease with a history of falls.

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Bekkers, Esther M J; Dockx, Kim; Heremans, Elke; Vercruysse, Sarah; Verschueren, Sabine M P; Mirelman, Anat; Nieuwboer, Alice

2014-01-01

Proprioceptive deficits negatively affect postural control but their precise contribution to postural instability in Parkinson's disease (PD) is unclear. We investigated if proprioceptive manipulations differentially affect balance, measured by force plates, during quiet standing in 13 PD patients and 13 age-matched controls with a history of falls. Perceived limits of stability (LoS) were derived from the differences between maximal center of pressure (CoP) displacement in anterior-posterior (AP) and medio-lateral (ML) direction during a maximal leaning task. Task conditions comprised standing with eyes open (EO) and eyes closed (EC): (1) on a stable surface; (2) an unstable surface; and (3) with Achilles tendon vibration. CoP displacements were calculated as a percentage of their respective LoS. Perceived LoS did not differ between groups. PD patients showed greater ML CoP displacement than elderly fallers (EF) across all conditions (p = 0.043) and tended to have higher postural sway in relation to the LoS (p = 0.050). Both groups performed worse on an unstable surface and during tendon vibration compared to standing on a stable surface with EO and even more so with EC. Both PD and EF had more AP sway in all conditions with EC compared to EO (p postural control in fallers with and without PD. PD fallers showed higher ML sway after sensory manipulations, as a result of which these values approached their perceived LoS more closely than in EF. We conclude that despite a similar fall history, PD patients showed more ML instability than EF, irrespective of sensory manipulation, but had a similar reliance on ankle proprioception. Hence, we recommend that rehabilitation and fall prevention for PD should focus on motor rather than on sensory aspects.

Effects of the anchor system on postural control in older Adults

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Eliane Mauerberg de Castro

2012-03-01

Full Text Available Falls are common during aging, and can have drastic consequences. Within this context, maintaining the ability to balance plays an essential role in enabling older adults to continue to perform their daily activities. Therefore, the use of interventional and treatment tools for development of balance becomes essential. The objective of this study was to analyze the anchor system as a potential tool for decreasing body sway in older and young adults. Older adults had more postural sway than their young counterparts. The absence of visual information led to larger instability in both groups. The anchor system improved postural stability of both groups. Thus, it may be a useful tool for posture stabilization in old and young adults.

Effects of joint mobilization on chronic ankle instability: a randomized controlled trial.

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Cruz-Díaz, David; Lomas Vega, Rafael; Osuna-Pérez, Maria Catalina; Hita-Contreras, Fidel; Martínez-Amat, Antonio

2015-01-01

To evaluate the effects of joint mobilization, in which movement is applied to the ankle's dorsiflexion range of motion, on dynamic postural control and on the self-reported instability of patients with chronic ankle instability (CAI). A double-blind, placebo-controlled, randomized trial with repeated measures and a follow-up period. Ninety patients with a history of recurrent ankle sprain, self-reported instability, and a limited dorsiflexion range of motion, were randomly assigned to either the intervention group (Joint Mobilizations, 3 weeks, two sessions per week) the placebo group (Sham Mobilizations, same duration as joint mobilization) or the control group, with a 6 months follow-up. Dorsiflexion Range of Motion (DFROM), Star Excursion Balance Test (SEBT) and CAI Tool (CAIT) were outcome measures. A separate 3 × 4 mixed model analysis of variance was performed to examine the effect of treatment conditions and time, and intention-to-treat (ITT) analysis was applied to evaluate the effect of the independent variable. The application of joint mobilization resulted in better scores of DFROM, CAIT, and SEBTs in the intervention group when compared with the placebo or the control groups (p ankle DFROM, postural control, and self-reported instability. These results suggest that joint mobilization could be applied to patients with recurrent ankle sprain to help restore their functional stability. Implications for Rehabilitation Functional instability is a very common sequela in patients with CAI, resulting in reduced quality of living due to the limitations it imposes on daily life activities. The mobilization with movement technique presented by Mulligan, and based on the joint mobilization accompanied by active movement, appears as a valuable tool to be employed by physical therapists to restore ankle function after a recurrent ankle sprain history. ROM restriction, subjective feeling of instability and dynamic postural control are benefiting from the joint

Influence of pain on postural control in women with neck pain

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Juliana Soares

2013-04-01

Full Text Available The objective of this study was to investigate the influence of pain on postural control in women with neck pain and the relationship with possible changes in sensory systems and posture. The neck pain group was composed of women, aged between 20 and 50years, complaining of neck pain for more than three months; the control group was composed of women without complaints of neck pain. For the characterization of the groups, we used anamnesis, neck disability index and Visual Analogue Scale. Postural balance was assessed on force platform. Postural balance with manipulation of the sensory systems was measured by Foam Laser Dynamic Posturography, exposing the individual to six sensory organization tests. Posture was assessed by the Postural Assessment Software. The normality of the variables were verified using Shapiro-Wilk test, Student’s t-test and Mann-Whitney test for comparison between groups, with a significance level of5%. Groups were homogeneous in demographic variables. We observed higher amplitude and displacement velocity of the center of pressure in the neck pain group, showing greater postural balance. There were significant diferences incraniovertebral angle, showing forward head posture in symptomatic women. In dynamics posturography, we observed a difference between the groups: the score obtainedin the six sensory conditions showed that neck pain group presented greater balance impairment. Neck pain and forward head posture have a deleterious effect on postural control in symptomatic women, both in the static posture and dynamic posture.

Neural basis of postural focus effect on concurrent postural and motor tasks: phase-locked electroencephalogram responses.

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Huang, Cheng-Ya; Zhao, Chen-Guang; Hwang, Ing-Shiou

2014-11-01

Dual-task performance is strongly affected by the direction of attentional focus. This study investigated neural control of a postural-suprapostural procedure when postural focus strategy varied. Twelve adults concurrently conducted force-matching and maintained stabilometer stance with visual feedback on ankle movement (visual internal focus, VIF) and on stabilometer movement (visual external focus, VEF). Force-matching error, dynamics of ankle and stabilometer movements, and event-related potentials (ERPs) were registered. Postural control with VEF caused superior force-matching performance, more complex ankle movement, and stronger kinematic coupling between the ankle and stabilometer movements than postural control with VIF. The postural focus strategy also altered ERP temporal-spatial patterns. Postural control with VEF resulted in later N1 with less negativity around the bilateral fronto-central and contralateral sensorimotor areas, earlier P2 deflection with more positivity around the bilateral fronto-central and ipsilateral temporal areas, and late movement-related potential commencing in the left frontal-central area, as compared with postural control with VIF. The time-frequency distribution of the ERP principal component revealed phase-locked neural oscillations in the delta (1-4Hz), theta (4-7Hz), and beta (13-35Hz) rhythms. The delta and theta rhythms were more pronounced prior to the timing of P2 positive deflection, and beta rebound was greater after the completion of force-matching in VEF condition than VIF condition. This study is the first to reveal the neural correlation of postural focusing effect on a postural-suprapostural task. Postural control with VEF takes advantage of efficient task-switching to facilitate autonomous postural response, in agreement with the "constrained-action" hypothesis. Copyright © 2014 Elsevier B.V. All rights reserved.

The Contribution of Proprioceptive Information to Postural Control in Elderly and Patients with Parkinson’s Disease with a History of Falls

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Bekkers, Esther M. J.; Dockx, Kim; Heremans, Elke; Vercruysse, Sarah; Verschueren, Sabine M. P.; Mirelman, Anat; Nieuwboer, Alice

2014-01-01

Proprioceptive deficits negatively affect postural control but their precise contribution to postural instability in Parkinson’s disease (PD) is unclear. We investigated if proprioceptive manipulations differentially affect balance, measured by force plates, during quiet standing in 13 PD patients and 13 age-matched controls with a history of falls. Perceived limits of stability (LoS) were derived from the differences between maximal center of pressure (CoP) displacement in anterior–posterior (AP) and medio-lateral (ML) direction during a maximal leaning task. Task conditions comprised standing with eyes open (EO) and eyes closed (EC): (1) on a stable surface; (2) an unstable surface; and (3) with Achilles tendon vibration. CoP displacements were calculated as a percentage of their respective LoS. Perceived LoS did not differ between groups. PD patients showed greater ML CoP displacement than elderly fallers (EF) across all conditions (p = 0.043) and tended to have higher postural sway in relation to the LoS (p = 0.050). Both groups performed worse on an unstable surface and during tendon vibration compared to standing on a stable surface with EO and even more so with EC. Both PD and EF had more AP sway in all conditions with EC compared to EO (p postural control in fallers with and without PD. PD fallers showed higher ML sway after sensory manipulations, as a result of which these values approached their perceived LoS more closely than in EF. We conclude that despite a similar fall history, PD patients showed more ML instability than EF, irrespective of sensory manipulation, but had a similar reliance on ankle proprioception. Hence, we recommend that rehabilitation and fall prevention for PD should focus on motor rather than on sensory aspects. PMID:25505395

Kinematics of the human mandible for different head postures.

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Visscher, C M; Huddleston Slater, J J; Lobbezoo, F; Naeije, M

2000-04-01

The influence of head posture on movement paths of the incisal point (IP) and of the mandibular condyles during free open-close movements was studied. Ten persons, without craniomandibular or cervical spine disorders, participated in the study. Open close mandibular movements were recorded with the head in five postures, viz., natural head posture, forward head posture, military posture, and lateroflexion to the right and to the left side, using the Oral Kinesiologic Analysis System (OKAS-3D). This study showed that in a military head posture, the opening movement path of the incisal point is shifted anteriorly relative to the path in a natural head posture. In a forward head posture, the movement path is shifted posteriorly whereas during lateroflexion, it deviates to the side the head has moved to. Moreover, the intra-articular distance in the temporomandibular joint during closing is smaller with the head in military posture and greater in forward head posture, as compared to the natural head posture. During lateroflexion, the intra-articular distance on the ipsilateral side is smaller. The influence of head posture upon the kinematics of the mandible is probably a manifestation of differences in mandibular loading in the different head postures.

The contribution of proprioceptive information to postural control in elderly and patients with Parkinson’s disease with a history of falls

Directory of Open Access Journals (Sweden)

Esther Maria Johanna Bekkers

2014-11-01

Full Text Available Proprioceptive deficits negatively affect postural control but their precise contribution to postural instability in Parkinson’s disease (PD is unclear. We investigated if proprioceptive manipulations differentially affect balance, measured by force plates, during quiet standing in 13 PD patients and 13 age-matched controls with a history of falls. Perceived limits of stability (LoS were derived from the differences between maximal center of pressure (CoP displacement in anterior-posterior (AP and medio-lateral (ML direction during a maximal leaning task. Task conditions comprised standing with eyes open (EO and eyes closed (EC, (1 on a stable surface; (2 an unstable surface and (3 with Achilles tendon vibration. CoP displacements were calculated as a percentage of their respective LoS. Perceived LoS did not differ between groups. PD patients showed greater ML CoP displacement than elderly fallers (EF across all conditions (p = 0.043 and tended to have higher postural sway in relation to the LoS (p = 0.050. Both groups performed worse on an unstable surface and during tendon vibration compared to standing on a stable surface with EO and even more so with EC. Both PD and EF had more AP sway in all conditions with EC compared to EO (p < 0.001 and showed increased CoP displacements when relying on proprioception only compared to standing with normal sensory input. This implies a similar role of the proprioceptive system in postural control in fallers with and without PD. PD fallers showed higher ML sway after sensory manipulations disturbing postural control, as a result of which these values approached their perceived LoS more closely than in EF. We conclude that despite a similar fall history, PD patients showed more ML instability than EF, irrespective of sensory manipulation, but had a similar reliance on ankle proprioception. Hence, we recommend that rehabilitation and fall prevention for PD should focus on motor rather than on sensory

Light touch contact improves pain-evoked postural instability during quiet standing

DEFF Research Database (Denmark)

Hirata, Rogerio P.; Christensen, Steffan W.; Agger, Simone

2018-01-01

for 40 seconds with their eyes closed. Their postural stability was quantified by the area and velocity of center of pressure (CoP) displacement. The CoP was recorded with and without pain during two different conditions: 1) no touch and 2) the subjects were asked to lightly touch a curtain...

Absence of Rotation Perception during Warm Water Caloric Irrigation in Some Seniors with Postural Instability.

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Chiarovano, Elodie; Vidal, Pierre-Paul; Magnani, Christophe; Lamas, Georges; Curthoys, Ian S; de Waele, Catherine

2016-01-01

Falls in seniors are a major public health problem. Falls lead to fear of falling, reduced mobility, and decreased quality of life. Vestibular dysfunction is one of the fall risk factors. The relationship between objective measures of vestibular responses and age has been studied. However, the effects of age on vestibular perception during caloric stimulation have not been studied. Twenty senior subjects were included in the study, and separated in two groups: 10 seniors reporting postural instability (PI) and exhibiting absence of vestibular perception when they tested with caloric stimulation and 10 sex- and age-matched seniors with no such problems (controls). We assessed vestibular perception on a binary rating scale during the warm irrigation of the caloric test. The function of the various vestibular receptors was assessed using video head impulse test (vHIT), caloric tests, and cervical and ocular vestibular-evoked myogenic potentials. The Equitest was used to evaluate balance. No horizontal canal dysfunction assessed using both caloric test and vHIT was detected in either group. No significant difference was detected between PI and control groups for the peak SPV of caloric-induced ocular nystagmus or for the HVOR gain. All the controls perceived rotation when the maximal SPV during warm irrigation was equal to or ≥15°/s. None of the subjects in the PI group perceived rotation even while the peak SPV exceeded 15°/s, providing objective evidence of normal peripheral horizontal canal function. All the PI group had abnormal Equitest results, particularly in the two last conditions. These investigations show for the first time that vestibular perception can be absent during a caloric test despite normal horizontal canal function. We call this as dissociation vestibular neglect. Patients with poor vestibular perception may not be aware of postural perturbations and so will not correct for them. Thus, falls in the elderly may result, among other factors, from

Spherical Lenses and Prisms Lead to Postural Instability in Both Dyslexic and Non Dyslexic Adolescents

Science.gov (United States)

Kapoula, Zoi; Gaertner, Chrystal; Matheron, Eric

2012-01-01

There is controversy as to whether dyslexic children present systematic postural deficiency. Clinicians use a combination of ophthalmic prisms and proprioceptive soles to improve postural performances. This study examines the effects of convergent prisms and spherical lenses on posture. Fourteen dyslexics (13–17 years-old) and 11 non dyslexics (13–16 years-old) participated in the study. Quiet stance posturography was performed with the TechnoConcept device while subjects fixated a target at eye-level from a distance of 1_m. Four conditions were run: normal viewing; viewing the target with spherical lenses of −1 diopter (ACCOM1) over each eye; viewing with −3 diopters over each eye (ACCOM3); viewing with a convergent prism of 8 diopters per eye. Relative to normal viewing, the −1 lenses increased the surface of body sway significantly whereas the −3 diopter lenses only resulted in a significant increase of antero-posterior body sway. Thus, adolescents would appear to cope more effectively with stronger conflicts rather than subtle ones. The prism condition resulted in a significant increase in both the surface and the antero-posterior body sway. Importantly, all of these effects were similar for the two groups. Wavelet analysis (time frequency domain) revealed high spectral power of antero-posterior sway for the prism condition in both groups. In the ACCOM3 condition, the spectral power of antero-posterior sway decreased for non dyslexics but increased for dyslexics suggesting that dyslexics encounter more difficulty with accommodation. The cancelling time for medium range frequency (believed to be controlled by the cerebellum), was shorter in dyslexics, suggesting fewer instances of optimal control. We conclude that dyslexics achieve similar postural performances albeit less efficiently. Prisms and lenses destabilize posture for all teenagers. Thus, contrary to adults, adolescents do not seem to use efferent, proprioceptive ocular motor signals to

Spherical lenses and prisms lead to postural instability in both dyslexic and non dyslexic adolescents.

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Zoi Kapoula

Full Text Available There is controversy as to whether dyslexic children present systematic postural deficiency. Clinicians use a combination of ophthalmic prisms and proprioceptive soles to improve postural performances. This study examines the effects of convergent prisms and spherical lenses on posture. Fourteen dyslexics (13-17 years-old and 11 non dyslexics (13-16 years-old participated in the study. Quiet stance posturography was performed with the TechnoConcept device while subjects fixated a target at eye-level from a distance of 1_m. Four conditions were run: normal viewing; viewing the target with spherical lenses of -1 diopter (ACCOM1 over each eye; viewing with -3 diopters over each eye (ACCOM3; viewing with a convergent prism of 8 diopters per eye. Relative to normal viewing, the -1 lenses increased the surface of body sway significantly whereas the -3 diopter lenses only resulted in a significant increase of antero-posterior body sway. Thus, adolescents would appear to cope more effectively with stronger conflicts rather than subtle ones. The prism condition resulted in a significant increase in both the surface and the antero-posterior body sway. Importantly, all of these effects were similar for the two groups. Wavelet analysis (time frequency domain revealed high spectral power of antero-posterior sway for the prism condition in both groups. In the ACCOM3 condition, the spectral power of antero-posterior sway decreased for non dyslexics but increased for dyslexics suggesting that dyslexics encounter more difficulty with accommodation. The cancelling time for medium range frequency (believed to be controlled by the cerebellum, was shorter in dyslexics, suggesting fewer instances of optimal control. We conclude that dyslexics achieve similar postural performances albeit less efficiently. Prisms and lenses destabilize posture for all teenagers. Thus, contrary to adults, adolescents do not seem to use efferent, proprioceptive ocular motor signals to

Contribution of Head Position, Standing Surface, and Vision to Postural Control in Community-Dwelling Older Adults.

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Pociask, Fredrick D; DiZazzo-Miller, Rosanne; Goldberg, Allon; Adamo, Diane E

2016-01-01

Postural control requires the integration of sensorimotor information to maintain balance and to properly position and orient the body in response to external stimuli. Age-related declines in peripheral and central sensory and motor function contribute to postural instability and falls. This study investigated the contribution of head position, standing surface, and vision on postural sway in 26 community-dwelling older adults. Participants were asked to maintain a stable posture under conditions that varied standing surface, head position, and the availability of visual information. Significant main and interaction effects were found for all three factors. Findings from this study suggest that postural sway responses require the integration of available sources of sensory information. These results have important implications for fall risks in older adults and suggest that when standing with the head extended and eyes closed, older adults may place themselves at risk for postural disequilibrium and loss of balance. Copyright © 2016 by the American Occupational Therapy Association, Inc.

Mild hallux valgus angle affects single-limb postural stability in asymptomatic subjects.

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Çınar-Medeni, Özge; Atalay Guzel, Nevin; Basar, Selda

2016-01-01

Single-limb postural stability is a key component of lower extremity functional status. Factors affecting postural stability should be well defined to prevent injuries. The aim of this study was to investigate the effect of the hallux valgus angle on postural stability in asymptomatic subjects. A total of 19 subjects were included in the study. The hallux valgus angle and postural stability were assessed. Participants were assigned to two groups according to whether the hallux valgus angle was pathological or not. A hallux valgus angle greater than 15 degrees was accepted as pathological. The relationship between the hallux valgus angle and postural stability, and the differences in postural stability scores between the two groups were analyzed. Postural stability was assessed with a stabilometer. The test was performed with the eyes open. We found a significant correlation between the hallux valgus angle and mediolateral and overall stability index (r= 0.484, p= 0.036; r = 0.463, p= 0.046 respectively). Subjects with a pathological mild hallux valgus angle had greater stability index scores than normal subjects (phallux valgus angle has negative effects on postural stability as a forefoot deformity. This deformity should be taken into account for injury prevention strategies in pain-free younger adults.

Effect of the Oculus Rift head mounted display on postural stability

DEFF Research Database (Denmark)

Epure, Paula; Gheorghe, Cristina; Nissen, Thomas

2014-01-01

board controlling a skiing game. Two tests were conducted: full-vision versus blindfolded and HMD versus monitor display. Results were that five of the six balance-impaired adults and six of the eight non-balance-impaired adults showed higher degree of postural stability while using a monitor display......This study explored how a HMD-experienced virtual environment influences physical balance of six balance-impaired adults 59-69 years-of-age, when compared to a control group of eight non-balance-impaired adults, 18-28 years-of-age. The setup included a Microsoft Kinect and a self-created balance....... Conclusions are that HMD, used in this context, leads to postural instability....

[Posture and gait disorders and the incidence of falling in patients with Parkinson].

Science.gov (United States)

Cano-de la Cuerda, R; Macías-Jiménez, A I; Cuadrado-Pérez, M L; Miangolarra-Page, J C; Morales-Cabezas, M

Although falls are one of the main causes of morbidity and mortality in patients with Parkinson's disease, studies about its incidence and predicting factors are scarce. Our study involved 25 patients with PD (15 males and 10 females; age: 75.8 +/- 6.5 years). A closed survey was used to determine a retrospective record of falls during the last year. An analysis was performed to examine whether there was a relationship with Hoehn and Yahr staging, the score on the Up and Go scale or the Barthel index and with possible risk factors for falls. All the patients had suffered falls at some time over the last year (mean number of falls: 6.5 +/- 3.8). 56% of the falls happened during the phases of the day when patient mobility was at its highest. A significant correlation was found between the number of falls and the Hoehn and Yahr and the Up and Go scores. The number of falls was significantly higher in patients with loss of postural reflexes, the need for help in order to walk, and blockage and festination phenomena. No association was found with fear of falling, visual alterations or postural lateralisation. Association with the Barthel index and dependence for activities of daily living reached almost significant levels. Postural instability and disorders affecting gait appear to be the factors that give patients with PD a greater propensity to fall. Patients who present such alterations should be submitted to rehabilitation therapy aimed at preventing them from falling.

STEADFAST: Psychotherapeutic Intervention Improves Postural Strategy of Somatoform Vertigo and Dizziness

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Christoph Best

2015-01-01

Full Text Available Patients with somatoform vertigo and dizziness (SVD disorders often report instability of stance or gait and fear of falling. Posturographic measurements indeed indicated a pathological postural strategy. Our goal was to evaluate the effectiveness of a psychotherapeutic and psychoeducational short-term intervention (PTI using static posturography and psychometric examination. Seventeen SVD patients took part in the study. The effects of PTI on SVD were evaluated with quantitative static posturography. As primary endpoint a quotient characterizing the relation between horizontal and vertical sway was calculated (QH/V, reflecting the individual postural strategy. Results of static posturography were compared to those of age- and gender-matched healthy volunteers (n=28; baseline measurements were compared to results after PTI. The secondary endpoint was the participation-limiting consequences of SVD as measured by the Vertigo Handicap Questionnaire (VHQ. Compared to the healthy volunteers, the patients with SVD showed a postural strategy characterized by stiffening-up that resulted in a significantly reduced body sway quotient before PTI (patients: QH/V=0.31 versus controls: QH/V=0.38; p=0.022. After PTI the postural behavior normalized, and psychological distress was reduced. PTI therefore appears to modify pathological balance behaviour. The postural strategy of patients with SVD possibly results from anxious anticipatory cocontraction of the antigravity muscles.

Relationships among head posture, pain intensity, disability and deep cervical flexor muscle performance in subjects with postural neck pain

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Arun V. Subbarayalu, PhD

2017-12-01

Full Text Available Objectives: Information Technology (IT professionals working with computers gradually develop forward head posture and, as a result, these professionals are susceptible to several neck disorders. This study intended to reveal the relationships between pain intensity, disability, head posture and deep cervical flexor (DCF muscle performance in patients with postural neck pain. Methods: A cross-sectional study was conducted on 84 IT professionals who were diagnosed with postural neck pain. The participants were recruited with a random sampling approach. A Visual Analogue Scale (VAS, the Northwick Park Neck Pain Questionnaire (NPQ, the Modified Head Posture Spinal Curvature Instrument (MHPSCI, and the Stabilizer Pressure Biofeedback Unit were used to measure neck pain intensity, neck disability, head posture, and DCF muscle performance, respectively. Results: The Pearson correlation coefficient revealed a significantly strong positive relationship between the VAS and the NPQ (r = 0.734. The cranio-vertebral (CV angle was found to have a significantly negative correlation with the VAS (r = −0.536 and a weak negative correlation with the NPQ (r = −0.389. Conclusion: This study concluded that a smaller CV angle corresponded to greater neck pain intensity and disability. Furthermore, there is no significant relationship between CV angle and DCF muscle performance, indicating that head posture re-education through postural correction exercises would not completely correct the motor control deficits in DCF muscles. In addition, a suitable exercise regimen that exclusively targets the deep cervical flexor muscle to improve its endurance is warranted. Keywords: Craniovertebral angle, Disability deep cervical flexors muscle performance, Head posture, Postural neck pain

Postural effects when cycling in late pregnancy.

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O'Neill, Maureen E; Cooper, Karen A; Boyce, E Stewart; Hunyor, Stephen N

2006-12-01

This study assessed if upright cycling is preferable to semi-recumbent cycling during pregnancy. Healthy women with low risk singleton pregnancies were tested at 34-38 weeks gestation. They cycled for 12 min, either semi-recumbent (45 degrees, n = 27) or upright (n = 23), at 135-145 beats min(-1). When semi-recumbent, minute ventilation was greater (pposture-independent. All increased with exercise (p0.05). Small post-exercise fetal heart rate increases (by 8 beats min(-1), ppostures (n = 11 in each sub-group), with no adverse changes. Fetal heart rate accelerations and uterine activity (n = 11 in each sub-group) were not influenced by posture or exercise. (1) Neither posture had a distinct advantage. (2) Both postures were safe for short duration cycling. (3) The same target maternal heart rates are suitable for both postures because they resulted in similar oxygen consumptions and fetal heart rates.

Relationship Between Postural Control and Restricted, Repetitive Behaviors in Autism Spectrum Disorders

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Krestin eRadonovich

2013-05-01

Full Text Available Restricted, repetitive behaviors (RRBs are one of the core diagnostic criteria of autism spectrum disorders (ASD, and include simple repetitive motor behaviors and more complex cognitive behaviors, such as compulsions and restricted interests. In addition to the core symptoms, impaired movement is often observed in ASD. Research suggests that the postural system in individuals with ASD is immature and may never reach adult levels. RRBs have been related to postural sway in individuals with mental retardation.Our goals were to determine whether subjects with ASD had greater postural sway and whether RBS-R scores were related to the magnitude of postural sway. We compared the center of pressure (COP sway area during quiet stance with scores on the Repetitive Behavior Scale-Revised (RBS-R in children with ASD and typically developing controls (TD ages 3-16. All subjects had Nonverbal IQ>70. Subjects performed four quiet stance trials at a self–selected stance width for 15 seconds. Subjects with ASD had greater postural sway area compared to controls. Not surprisingly, subjects with ASD exhibited greater frequencies and intensities of RRBs overall and on all 6 subscales. Further, there was a positive correlation between postural sway area and presence of RRBs. Interestingly, results of the postural sway area for the ASD group suggests that roughly half of the ASD subjects scored comparable to TD controls, whereas the other half scored >2 SD worse. Motor impaired children did not have significantly worse IQ scores, but were younger and had more RRBs.Results support previous findings of relationships between RRBs and postural control. It appears that motor control impairments may characterize a subset of individuals with ASD. Better delineation of motor control abilities in individuals with ASD will be important to help explain variations of abilities in ASD, inform treatment, and guide examination of underlying neural involvement in this diverse

Enhanced balance associated with coordination training with stochastic resonance stimulation in subjects with functional ankle instability: an experimental trial

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Brown Cathleen N

2007-12-01

Full Text Available Abstract Background Ankle sprains are common injuries that often lead to functional ankle instability (FAI, which is a pathology defined by sensations of instability at the ankle and recurrent ankle sprain injury. Poor postural stability has been associated with FAI, and sports medicine clinicians rehabilitate balance deficits to prevent ankle sprains. Subsensory electrical noise known as stochastic resonance (SR stimulation has been used in conjunction with coordination training to improve dynamic postural instabilities associated with FAI. However, unlike static postural deficits, dynamic impairments have not been indicative of ankle sprain injury. Therefore, the purpose of this study was to examine the effects of coordination training with or without SR stimulation on static postural stability. Improving postural instabilities associated with FAI has implications for increasing ankle joint stability and decreasing recurrent ankle sprains. Methods This study was conducted in a research laboratory. Thirty subjects with FAI were randomly assigned to either a: 1 conventional coordination training group (CCT; 2 SR stimulation coordination training group (SCT; or 3 control group. Training groups performed coordination exercises for six weeks. The SCT group received SR stimulation during training, while the CCT group only performed coordination training. Single leg postural stability was measured after the completion of balance training. Static postural stability was quantified on a force plate using anterior/posterior (A/P and medial/lateral (M/L center-of-pressure velocity (COPvel, M/L COP standard deviation (COPsd, M/L COP maximum excursion (COPmax, and COP area (COParea. Results Treatment effects comparing posttest to pretest COP measures were highest for the SCT group. At posttest, the SCT group had reduced A/P COPvel (2.3 ± 0.4 cm/s vs. 2.7 ± 0.6 cm/s, M/L COPvel (2.6 ± 0.5 cm/s vs. 2.9 ± 0.5 cm/s, M/L COPsd (0.63 ± 0.12 cm vs. 0.73 ± 0

Is weight-bearing asymmetry associated with postural instability after stroke? A systematic review.

NARCIS (Netherlands)

Kamphuis, J.F.; Kam, D.C.J. de; Geurts, A.C.H.; Weerdesteijn, V.G.M.

2013-01-01

Introduction. Improvement of postural stability is an important goal during poststroke rehabilitation. Since weight-bearing asymmetry (WBA) towards the nonparetic leg is common, training of weight-bearing symmetry has been a major focus in post-stroke balance rehabilitation. It is assumed that

Embodied prosthetic arm stabilizes body posture, while unembodied one perturbs it.

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Imaizumi, Shu; Asai, Tomohisa; Koyama, Shinichi

2016-10-01

Senses of ownership (this arm belongs to me) and agency (I am controlling this arm) originate from sensorimotor system. External objects can be integrated into the sensorimotor system following long-term use, and recognized as one's own body. We examined how an (un)embodied prosthetic arm modulates whole-body control, and assessed the components of prosthetic embodiment. Nine unilateral upper-limb amputees participated. Four frequently used their prosthetic arm, while the others rarely did. Their postural sway was measured during quiet standing with or without their prosthesis. The frequent users showed greater sway when they removed the prosthesis, while the rare users showed greater sway when they fitted the prosthesis. Frequent users reported greater everyday feelings of postural stabilization by prosthesis and a larger sense of agency over the prosthesis. We suggest that a prosthetic arm maintains or perturbs postural control, depending on the prosthetic embodiment, which involves sense of agency rather than ownership. Copyright © 2016 Elsevier Inc. All rights reserved.

STEADFAST: Psychotherapeutic Intervention Improves Postural Strategy of Somatoform Vertigo and Dizziness

Science.gov (United States)

Best, Christoph; Tschan, Regine; Stieber, Nikola; Beutel, Manfred E.; Eckhardt-Henn, Annegret; Dieterich, Marianne

2015-01-01

Patients with somatoform vertigo and dizziness (SVD) disorders often report instability of stance or gait and fear of falling. Posturographic measurements indeed indicated a pathological postural strategy. Our goal was to evaluate the effectiveness of a psychotherapeutic and psychoeducational short-term intervention (PTI) using static posturography and psychometric examination. Seventeen SVD patients took part in the study. The effects of PTI on SVD were evaluated with quantitative static posturography. As primary endpoint a quotient characterizing the relation between horizontal and vertical sway was calculated (Q H/V), reflecting the individual postural strategy. Results of static posturography were compared to those of age- and gender-matched healthy volunteers (n = 28); baseline measurements were compared to results after PTI. The secondary endpoint was the participation-limiting consequences of SVD as measured by the Vertigo Handicap Questionnaire (VHQ). Compared to the healthy volunteers, the patients with SVD showed a postural strategy characterized by stiffening-up that resulted in a significantly reduced body sway quotient before PTI (patients: Q H/V = 0.31 versus controls: Q H/V = 0.38; p = 0.022). After PTI the postural behavior normalized, and psychological distress was reduced. PTI therefore appears to modify pathological balance behaviour. The postural strategy of patients with SVD possibly results from anxious anticipatory cocontraction of the antigravity muscles. PMID:26843786

Do older adults perceive postural constraints for reach estimation?

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Cordova, Alberto; Gabbard, Carl

2014-01-01

BACKGROUND/STUDY CONTEXT: Recent evidence indicates that older persons have difficulty mentally representing intended movements. Furthermore, in an estimation of reach paradigm using motor imagery, a form of mental representation, older persons significantly overestimated their ability compared with young adults. The authors tested the notion that older adults may also have difficulty perceiving the postural constraints associated with reach estimation. The authors compared young (Mage = 22 years) and older (Mage = 67) adults on reach estimation while seated and in a more postural demanding standing and leaning forward position. The expectation was a significant postural effect with the standing condition, as evidenced by reduced overestimation. Whereas there was no difference between groups in the seated condition (both overestimated), older adults underestimated whereas the younger group once again overestimated in the standing condition. From one perspective, these results show that older adults do perceive postural constraints in light of their own physical capabilities. That is, that group perceived greater postural demands with the standing posture and elected to program a more conservative strategy, resulting in underestimation.

Craniocervical Posture in Patients with Obstructive Sleep Apnea

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Piccin, Chaiane Facco

2016-07-01

Full Text Available Introduction Obstructive Sleep Apnea (OSA is characterized by repeated episodes of upper airway obstruction during sleep. Objective The objective of this study is to verify the craniofacial characteristics and craniocervical posture of OSA and healthy subjects, determining possible relationships with the apnea/hypopnea index (AHI. Methods This case-control study evaluated 21 subjects with OSA, who comprised the OSA group (OSAG, and 21 healthy subjects, who constituted the control group (CG. Cephalometry analyzed head posture measurements, craniofacial measurements, and air space. Head posture was also assessed by means of photogrammetry. Results The groups were homogeneous regarding gender (12 men and 9 women in each group, age (OSAG = 41.86 ± 11.26 years; GC = 41.19 ± 11.20 years, and body mass index (OSAG = 25.65 ± 2.46 kg/m2; CG = 24.72 ± 3.01 kg/m2. We found significant differences between the groups, with lower average pharyngeal space and greater distance between the hyoid bone and the mandibular plane in OSAG, when compared with CG. A positive correlation was found between higher head hyperextension and head anteriorization, with greater severity of OSA as assessed by AHI. Conclusion OSAG subjects showed changes in craniofacial morphology, with lower average pharyngeal space and greater distance from the hyoid bone to the mandibular plane, as compared with healthy subjects. Moreover, in OSA subjects, the greater the severity of OSA, the greater the head hyperextension and anteriorization.

The Effect of Joint Mobilization on Dynamic Postural Control in Patients With Chronic Ankle Instability: A Critically Appraised Topic.

Science.gov (United States)

Kosik, Kyle B; Gribble, Phillip A

2018-01-01

Clinical Scenario: Dorsiflexion range of motion is an important factor in the performance of the Star Excursion Balance Test (SEBT). While patients with chronic ankle instability (CAI) commonly experience decreased reach distances on the SEBT, ankle joint mobilization has been suggested to be an effective therapeutic intervention for targeting dorsiflexion range of motion. What is the evidence to support ankle joint mobilization for improving performance on the SEBT in patients with CAI? Summary of Key Findings: The literature was searched for articles examining the effects of ankle joint mobilization on scores of the SEBT. A total of 3 peer-reviewed articles were retrieved, 2 prospective individual cohort studies and 1 randomized controlled trial. Only 2 articles demonstrated favorable results following 6 sessions of ankle joint mobilization. Clinical Bottom Line: Despite the mixed results, the majority of the available evidence suggests that ankle joint mobilization improves dynamic postural control. Strength of Recommendation: In accordance with the Centre of Evidence Based Medicine, the inconsistent results and the limited high-quality studies indicate that there is level C evidence to support the use of ankle joint mobilization to improve performance on the SEBT in patients with CAI.

Dual task interference on postural sway, postural transitions and gait in people with Parkinson's disease and freezing of gait.

Science.gov (United States)

de Souza Fortaleza, Ana Claudia; Mancini, Martina; Carlson-Kuhta, Patty; King, Laurie A; Nutt, John G; Chagas, Eliane Ferrari; Freitas, Ismael Forte; Horak, Fay B

2017-07-01

Freezing of gait (FoG) is associated with less automatic gait and more impaired cognition, balance and postural transitions compared to people with PD who do not have FoG. However, it is unknown whether dual-task cost during postural sway, postural transitions (such as gait initiation and turning), and gait are more in subjects with Parkinson's disease (PD) who have freezing of gait (FoG+) compared to those who do not have FoG (FoG-). Here, we hypothesized that the effects of a cognitive dual task on postural sway, postural transitions and gait would be larger in FoG+ than FoG-. Thirty FoG- and 24 FoG+ performed an Instrumented Stand and Walk test in OFF medication state, with and without a secondary cognitive task (serial subtraction by 3s). Measures of postural sway, gait initiation, turning, and walking were extracted using body-worn inertial sensors. FoG+ showed significantly larger dual task cost than FoG- for several gait metrics, but not during postural sway or postural transitions. During walking, FoG+ exhibited a larger dual task cost than FoG- resulting in shorter stride length and slower stride velocity. During standing, FoG+ showed a larger postural sway compared to FoG- and during gait initiation, FoG+, but not FoG-, showed a longer first step duration during the dual-task condition compared to single-task condition (interaction effect, p=0.04). During turning, both groups showed a slower turn peak speed in the dual-task condition compared to single task condition. These findings partly support our hypothesis that dual task cost on walking is greater in FoG+ than FoG-. Copyright © 2017. Published by Elsevier B.V.

Assessing Somatosensory Utilization during Unipedal Postural Control.

Science.gov (United States)

Goel, Rahul; De Dios, Yiri E; Gadd, Nichole E; Caldwell, Erin E; Peters, Brian T; Reschke, Millard F; Bloomberg, Jacob J; Oddsson, Lars I E; Mulavara, Ajitkumar P

2017-01-01

Multisensory-visual, vestibular and somatosensory information is integrated for appropriate postural control. The primary goal of this study was to assess somatosensory utilization during a functional motor task of unipedal postural control, in normal healthy adults. Assessing individual bias in the utilization of individual sensory contributions during postural control may help customization of rehabilitation protocols. In this study, a test paradigm of unipedal stance control in supine orientation with and without vision was assessed. Postural control in this test paradigm was hypothesized to utilize predominantly contributions of somatosensory information from the feet and ankle joint, with minimal vestibular input. Fourteen healthy subjects "stood" supine on their dominant leg while strapped to a backpack frame that was freely moving on air-bearings, to remove available otolith tilt cues with respect to gravity that influences postural control when standing upright. The backpack was attached through a cable to a pneumatic cylinder that provided a gravity-like load. Subjects performed three trials each with Eyes-open (EO) and Eyes-closed (EC) while loaded with 60% body weight. There was no difference in unipedal stance time (UST) across the two conditions with EC condition challenging the postural control system greater than the EO condition. Stabilogram-diffusion analysis (SDA) indicated that the critical mean square displacement was significantly different between the two conditions. Vestibular cues, both in terms of magnitude and the duration for which relevant information was available for postural control in this test paradigm, were minimized. These results support our hypothesis that maintaining unipedal stance in supine orientation without vision, minimizes vestibular contribution and thus predominantly utilizes somatosensory information for postural control.

Gabapentin can improve postural stability and quality of life in primary orthostatic tremor.

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Rodrigues, Julian P; Edwards, Dylan J; Walters, Susan E; Byrnes, Michelle L; Thickbroom, Gary; Stell, Rick; Mastaglia, Frank L

2005-07-01

Primary orthostatic tremor (OT) is characterized by leg tremor and instability on standing. High frequency (13-18 Hz) tremor bursting is present in leg muscles during stance, and posturography has shown greater than normal sway. We report on an open-label add-on study of gabapentin in 6 patients with OT. Six patients were studied with surface electromyography, force platform posturography, and a modified Parkinson's disease questionnaire (PDQ-39) quality of life (QOL) scale before and during treatment with gabapentin 300 mg t.d.s. If on other medications for OT, these were continued unchanged. Of the 6 patients, 4 reported a subjective benefit of 50 to 75% with gabapentin, 3 of whom showed reduced tremor amplitude and postural sway of up to 70%. Dynamic balance improved in all 3 patients who completed the protocol. QOL data from 5 patients showed improvement in all cases. No adverse effects were noted. Gabapentin may improve tremor, stability, and QOL in patients with OT, and symptomatic response correlated with a reduction in tremor amplitude and postural sway. The findings confirm previous reports of symptomatic benefit with gabapentin and provide justification for larger controlled clinical trials. Further work is required to establish the optimal dosage and to validate the methods used to quantify the response to treatment. Copyright 2005 Movement Disorder Society.

Postural control during one-leg stance in active and sedentary older people

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Leonardo George Victorio Victor

2014-09-01

Full Text Available Physical inactivity and aging are functional disability factors for older individuals, causing loss of balance and increasing the risk of falls. The purpose of this study was to compare the balance of physically independent older individuals, both participants and non-participants in a regular exercise program. Fifty six physically independent older participants were divided into G1ACTIVE = 28 individuals who participate in a regular exercise program and G2SEDENTARY = 28 individuals who did not participate in any physical exercise program. All participants underwent an eyes-open during one-leg balance test on a force platform. The postural oscillation parameters included center of pressure (COP; sway mean velocity and frequency of COP oscillations. G2 SEDENTARY showed higher postural instability than G1ACTIVE. Significant differences were observed for the main balance parameters. The results of this study support the concept that participation in regular physical activity is beneficial for postural balance of older individuals.

Postural orientation and equilibrium: what do we need to know about neural control of balance to prevent falls?

Science.gov (United States)

Horak, Fay B

2006-09-01

Postural control is no longer considered simply a summation of static reflexes but, rather, a complex skill based on the interaction of dynamic sensorimotor processes. The two main functional goals of postural behaviour are postural orientation and postural equilibrium. Postural orientation involves the active alignment of the trunk and head with respect to gravity, support surfaces, the visual surround and internal references. Sensory information from somatosensory, vestibular and visual systems is integrated, and the relative weights placed on each of these inputs are dependent on the goals of the movement task and the environmental context. Postural equilibrium involves the coordination of movement strategies to stabilise the centre of body mass during both self-initiated and externally triggered disturbances of stability. The specific response strategy selected depends not only on the characteristics of the external postural displacement but also on the individual's expectations, goals and prior experience. Anticipatory postural adjustments, prior to voluntary limb movement, serve to maintain postural stability by compensating for destabilising forces associated with moving a limb. The amount of cognitive processing required for postural control depends both on the complexity of the postural task and on the capability of the subject's postural control system. The control of posture involves many different underlying physiological systems that can be affected by pathology or sub-clinical constraints. Damage to any of the underlying systems will result in different, context-specific instabilities. The effective rehabilitation of balance to improve mobility and to prevent falls requires a better understanding of the multiple mechanisms underlying postural control.

Effects of focal ankle joint cooling on unipedal static balance in individuals with and without chronic ankle instability.

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Kim, Kyung-Min; Hart, Joseph M; Saliba, Susan A; Hertel, Jay

2015-01-01

Application of cryotherapy over an injured joint has been shown to improve muscle function, yet it is unknown how ankle cryotherapy affects postural control. Our purpose was to determine the effects of a 20-min focal ankle joint cooling on unipedal static stance in individuals with and without chronic ankle instability (CAI). Fifteen young subjects with CAI (9 males, 6 females) and 15 healthy gender-matched controls participated. All subjects underwent two intervention sessions on different days in which they had a 1.5L plastic bag filled with either crushed ice (active treatment) or candy corn (sham) applied to the ankle. Unipedal stance with eyes closed for 10s were assessed with a forceplate before and after each intervention. Center of pressure (COP) data were used to compute 10 specific dependent measures including velocity, area, standard deviation (SD), and percent range of COP excursions, and mean and SD of time-to-boundary (TTB) minima in the anterior-posterior (AP) and mediolateral directions. For each measure a three-way (Group-Intervention-Time) repeated ANOVAs found no significant interactions and main effects involving intervention (all Ps > 0.05). There were group main effects found for mean velocity (F(1,28) = 6.46, P = .017), area (F(1,28) = 12.83, P = .001), and mean of TTB minima in the AP direction (F(1,28) = 5.19, P = .031) indicating that the CAI group demonstrated greater postural instability compared to the healthy group. Postural control of unipedal stance was not significantly altered following focal ankle joint cooling in groups both with and without CAI. Ankle joint cryotherapy was neither beneficial nor harmful to single leg balance. Copyright © 2014 Elsevier B.V. All rights reserved.

Comparison of postural stability between injured and uninjured ballet dancers.

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Lin, Cheng-Feng; Lee, I-Jung; Liao, Jung-Hsien; Wu, Hong-Wen; Su, Fong-Chin

2011-06-01

Ballet movements require a limited base of support; thus, ballet dancers require a high level of postural control. However, postural stability in ballet dancers is still unclear and needs to be understood. To evaluate ballet dancers' postural stability in performing single-leg standing, the en pointe task, and the first and fifth positions and to determine differences in task performance among healthy nondancers, healthy dancers, and dancers with ankle sprains. Controlled laboratory study. Injured dancers, uninjured dancers, and nondancers were recruited for this study (N = 33 age-matched participants; n= 11 per group). The tasks tested were single-leg standing with eyes open and closed, first position, fifth position, and en pointe. Center of pressure parameters were calculated from the ground-reaction force collected with 1 force plate. Analysis of variance was used to assess the differences of center of pressure parameters among 3 groups in single-leg standing; independent t test was used to examine the differences of center of pressure parameters between injured and uninjured dancers. During single-leg standing, injured dancers had significantly greater maximum displacement in the medial-lateral direction and total trajectory of center of pressure, compared with the uninjured dancers and nondancers. During the first and fifth positions, the injured dancers demonstrated significantly greater standard deviation of center of pressure position in the medial-lateral and anterior-posterior directions, compared with the uninjured dancers. During en pointe, the injured dancers had significantly greater maximum displacement in the medial-lateral direction and the anterior-posterior direction, compared with the uninjured dancers. The injured and uninjured dancers demonstrated differences in postural stability in the medial-lateral direction during single-leg standing and the ballet postures. Although the injured dancers received ballet training, their postural stability

Quantitative Postural Analysis of Children With Congenital Visual Impairment.

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de Pádua, Michelle; Sauer, Juliana F; João, Silvia M A

2018-01-01

The aim of this study was to compare the postural alignment of children with visual impairment with that of children without visual impairment. The sample studied was 74 children of both sexes ages 5 to 12 years. Of these, 34 had visual impairment and 40 were control children. Digital photos from the standing position were used to analyze posture. Postural variables, such as tilt of the head, shoulder position, scapula position, lateral deviation of the spine, ankle position in the frontal plane and head posture, angle of thoracic kyphosis, angle of lumbar lordosis, pelvis position, and knee position in the frontal and sagittal planes, were measured with the Postural Assessment Software 0.63, version 36 (SAPO, São Paulo, Brazil), with markers placed in predetermined bony landmarks. The main results of this study showed that children with visual impairment have increased head tilt (P Visual impairment influences postural alignment. Children with visual impairment had increased head tilt, uneven shoulders, greater lateral deviation of the spine, thoracic kyphosis, lower lumbar lordosis, and more severe valgus deformities on knees. Copyright © 2017. Published by Elsevier Inc.

Analysis of postural sway in patients with normal pressure hydrocephalus: effects of shunt implantation

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Czerwosz L

2009-12-01

Full Text Available Abstract Poor postural balance is one of the major risk factors for falling in normal pressure hydrocephalus (NPH. Postural instability in the clinic is commonly assessed based upon force platform posturography. In this study we focused on the identification of changes in sway characteristics while standing quiet in patients with NPH before and after shunt implantation. Postural sway area and sway radius were analyzed in a group of 9 patients and 46 controls of both genders. Subject's spontaneous sway was recorded while standing quiet on a force platform for 30-60 s, with eyes open and then closed. Both analyzed sway descriptors identified between-group differences and also an effect of shunt implantation in the NPH group. Sway radius and sway area in patients exhibited very high values compared with those in the control group. Importantly, the effect of eyesight in patients was not observed before shunt implantation and reappeared after the surgical treatment. The study documents that static force platform posturography may be a reliable measure of postural control improvement due to shunt surgery.

Influence of the visual environment on the postural stability in healthy older women.

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Brooke-Wavell, K; Perrett, L K; Howarth, P A; Haslam, R A

2002-01-01

A poor postural stability in older people is associated with an increased risk of falling. It is recognized that visual environment factors (such as poor lighting and repeating patterns on escalators) may contribute to falls, but little is known about the effects of the visual environment on postural stability in the elderly. To determine whether the postural stability of older women (using body sway as a measure) differed under five different visual environment conditions. Subjects were 33 healthy women aged 65-76 years. Body sway was measured using an electronic force platform which identified the location of their centre of gravity every 0.05 s. Maximal lateral sway and anteroposterior sway were determined and the sway velocity calculated over 1-min trial periods. Body sway was measured under each of the following conditions: (1) normal laboratory lighting (186 lx); (2) moderate lighting (10 lx); (3) dim lighting (1 lx); (4) eyes closed, and (5) repeating pattern projected onto a wall. Each measure of the postural stability was significantly poorer in condition 4 (eyes closed) than in all other conditions. Anteroposterior sway was greater in condition 3 than in conditions 1 and 2, whilst the sway velocity was greater in condition 3 than in condition 2. Lateral sway did not differ significantly between different lighting levels (conditions 1-3). A projected repeating pattern (condition 5) did not significantly influence the postural stability relative to condition 1. The substantially greater body sway with eyes closed than with eyes open confirms the importance of vision in maintaining the postural stability. At the lowest light level, the body sway was significantly increased as compared with the other light levels, but was still substantially smaller than on closing the eyes. A projected repeating pattern did not influence the postural stability. Dim lighting levels and removing visual input appear to be associated with a poorer postural stability in older

Subthalamic nucleus stimulation and levodopa-resistant postural instability in Parkinson's disease.

NARCIS (Netherlands)

Visser, J.E.; Allum, J.H.J.; Carpenter, M.G.; Esselink, R.A.J.; Speelman, J.D.; Borm, G.F.; Bloem, B.R.

2008-01-01

We examined the effect of bilateral subthalamic nucleus stimulation on levodopa-resistant balance impairment in 14 patients with Parkinson's disease and 18 matched controls. Instability was quantitatively assessed using standardized multidirectional dynamic posturography. Patients were tested after

Subthalamic nucleus stimulation and levodopa-resistant postural instability in Parkinson's disease

NARCIS (Netherlands)

Visser, Jasper E.; Allum, John H. J.; Carpenter, Mark G.; Esselink, Rianne A.; Speelman, Johannes D.; Borm, George F.; Bloem, Bastiaan R.

2008-01-01

We examined the effect of bilateral subthalamic nucleus stimulation on levodopa-resistant balance impairment in 14 patients with Parkinson's disease and 18 matched controls. Instability was quantitatively assessed using standardized multidirectional dynamic posturography. Patients were tested after

Postural Stabilization Strategies to Motor Contagion Induced by Action Observation Are Impaired in Parkinson’s Disease

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Elisa Pelosin

2018-03-01

Full Text Available Postural reactions can be influenced by concomitant tasks or different contexts and are modulated by a higher order motor control. Recent studies investigated postural changes determined by motor contagion induced by action observation (chameleon effect showing that observing a model in postural disequilibrium induces an increase in healthy subjects’ body sway. Parkinson’s disease (PD is associated with postural instability and impairments in cognitively controlled balance tasks. However, no studies investigated if viewing postural imbalance might influence postural stability in PD and if patients are able to inhibit a visual postural perturbation. In this study, an action observation paradigm for assessing postural reaction to motor contagion in PD subjects and healthy older adults was used. Postural stability changes were measured during the observation of a static stimulus (control condition and during a point-light display of a gymnast balancing on a rope (biological stimulus. Our results showed that, during the observation of the biological stimulus, sway area and antero-posterior and medio-lateral displacements of center of pressure significantly increased only in PD participants, whereas correct stabilization reactions were present in elderly subjects. These results demonstrate that PD leads to a decreased capacity to control automatic imitative tendencies induced by motor contagion. This behavior could be the consequence either of an inability to inhibit automatic imitative tendencies or of the cognitive load requested by the task. Whatever the case, the issue about the ability to inhibit automatic imitative tendencies could be crucial for PD patients since it might increase falls risk and injuries.

The differences in postural reactions between scoliosis and scoliotic posture

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Jacek Wilczyński

2017-05-01

Full Text Available The aim of the research was to demonstrate the differences in amplitudes of postural reactions in girls with scoliotic posture and idiopathic scoliosis. 28 girls aged 7-18 years old were involved in the study. Children attended to the Interschool Centre of Corrective Exercises in Starachowice. The research was conducted in June 2011. Spine research was made by Exhibeon digital radiography. Based on the size of the angle of spinal curvature there were identified: scoliotic posture: 1-9° and scoliosis: ≥10°. Postural reactions were examined by static-dynamic Tecnobody’s ST 310 Plus Stability System platform. There were 21 (75% children with scoliotic posture, and 7 (25% with idiopathic scoliosis. Student's t-test showed a significantly higher postural reactions for scoliosis in relation to scoliotic postures in case of: Average Forward-Backward Speed (OE, (p=0,05, Medium-Lateral Standard Deviation X (CE, (p=0,002, and Ellipse area (CE, (p=0,012. To verify the significant differences, demonstrating the lack of homogeneity of variance, the Mann–Whitney U-test has been used, which showed a significant differences between the scoliotic posture and scoliosis in case of: Medium-Lateral Standard Deviation X (CE, (p=0,0012, Average Forward-Backward Speed (OE, (p=0,0548, and Ellipse area (CE (p=0,0047. Together with an increase of the angle of curvature, the value of these postural reactions also grew. Most of postural reactions didn’t fit the norm.

Do children perceive postural constraints when estimating reach or action planning?

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Gabbard, Carl; Cordova, Alberto; Lee, Sunghan

2009-03-01

Estimation of whether an object is reachable from a specific body position constitutes an important aspect in effective motor planning. Researchers who estimate reachability by way of motor imagery with adults consistently report the tendency to overestimate, with some evidence of a postural effect (postural stability hypothesis). This idea suggests that perceived reaching limits depend on an individual's perceived postural constraints. Based on previous work with adults, the authors expected a significant postural effect with the Reach 2 condition, as evidenced by reduced overestimation. Furthermore, the authors hypothesized that the postural effect would be greater in younger children. They then tested these propositions among children aged 7, 9, and 11 years by asking them to estimate reach while seated (Reach 1) and in the more demanding posture of standing on 1 foot and leaning forward (Reach 2). Results indicated no age or condition difference, therefore providing no support for a postural effect. When the authors compared these data to a published report of adults, a developmental difference emerged. That is, adults recognize the perceived postural constraint of the standing position resulting in under- rather than overestimation, as displayed in the seated condition. Although preliminary, these observations suggest that estimates of reach (action planning) continue to be refined between late childhood and young adulthood.

Validity and reliability of a dental operator posture assessment instrument (PAI).

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Branson, Bonnie G; Williams, Karen B; Bray, Kimberly Krust; Mcllnay, Sandy L; Dickey, Diana

2002-01-01

Basic operating posture is considered an important occupational health issue for oral health care clinicians. It is generally agreed that the physical posture of the operator, while providing care, should be such that all muscles are in a relaxed, well-balanced, and neutral position. Postures outside of this neutral position are likely to cause musculoskeletal discomfort. To date, the range of the neutral operator position has not been well-defined; nor have any specific instruments been identified that can quantitatively or semi-quantitatively assess dental operator posture. This paper reports on the development of an instrument that can be used to semi-quantitatively evaluate postural components. During the first phase of the study, an expert panel defined the basic parameters for acceptable, compromised, and harmful operator postures and established face validity of a posture assessment instrument (PAI). During the second phase, the PAI was tested for reliability using generalizability theory. Four raters tested the instrument for reliability. Overall, total PAI scores were similar amongst three of the raters, with the fourth rater's scores being slightly greater than the other three. The main effect of the rater on individual postural components was moderate, indicating that rater variance contributed to 11.9% of total variance. The PAI measures posture as it occurs and will have numerous applications when evaluating operator performance in the dental and dental hygiene education setting. Also, the PAI will prove useful when examining the effects of operator posture and musculoskeletal disorders.

Aging causes a reorganization of cortical and spinal control of posture

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Selma ePapegaaij

2014-03-01

Full Text Available Classical studies in animal preparations suggest a strong role for spinal control of posture. In young adults it is now established that the cerebral cortex contributes to postural control of unperturbed and perturbed standing. The age-related degeneration and accompanying functional changes in the brain, reported so far mainly in conjunction with simple manual motor tasks, may also affect the mechanisms that control complex motor tasks involving posture. This review outlines the age-related structural and functional changes at spinal and cortical levels and provides a mechanistic analysis of how such changes may be linked to the behaviorally manifest postural deficits in old adults. The emerging picture is that the age-related reorganization in motor control during voluntary tasks, characterized by differential modulation of spinal reflexes, greater cortical activation and cortical disinhibition, is also present during postural tasks. We discuss the possibility that this reorganization underlies the increased coactivation and dual task interference reported in elderly. Finally, we propose a model for future studies to unravel the structure-function-behavior relations in postural control and aging.

Postural sway in individuals with type 2 diabetes and concurrent benign paroxysmal positional vertigo.

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D'Silva, Linda J; Kluding, Patricia M; Whitney, Susan L; Dai, Hongying; Santos, Marcio

2017-12-01

diabetes has been shown to affect the peripheral vestibular end organs and is associated with an increase in the frequency of benign paroxysmal positional vertigo (BPPV). People with diabetes have higher postural sway; however, the impact of symptomatic BPPV on postural sway in individuals with diabetes is unclear. The purpose of this cross-sectional study was to examine postural sway in people with type 2 diabetes who have symptomatic, untreated BPPV (BPPVDM). fifty-two participants (mean age 56.9 ± 5.6 years) were enrolled: controls (n = 14), diabetes (n = 14), BPPV only (n = 13) and BPPVDM (n = 11). An inertial motion sensor was used to detect pelvic acceleration across five standing conditions with eyes open/closed on firm/foam surfaces. Range of acceleration (cm/s 2 ), peak velocity (cm/s) and variability of sway [root mean square (RMS)] in the anterior-posterior (AP) and medial-lateral (ML) directions were used to compare postural sway between groups across conditions. participants with BPPVDM had higher ranges of acceleration in the AP (p = 0.02) and ML (p = 0.02) directions, as well as higher peak velocity (p diabetes groups. Standing on foam with eyes closed and tandem stance were challenging conditions for people with BPPVDM. clinicians may consider using standing on foam with eyes closed and tandem standing with eyes open to assess postural control in people with BPPVDM to identify postural instability.

Determining postural stability

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Lieberman, Erez (Inventor); Forth, Katharine E. (Inventor); Paloski, William H. (Inventor)

2011-01-01

A method for determining postural stability of a person can include acquiring a plurality of pressure data points over a period of time from at least one pressure sensor. The method can also include the step of identifying a postural state for each pressure data point to generate a plurality of postural states. The method can include the step of determining a postural state of the person at a point in time based on at least the plurality of postural states.

Dose postural control improve following application of transcutaneous electrical nerve stimulation in diabetic peripheral neuropathic patients? A randomized placebo control trial.

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Saadat, Z; Rojhani-Shirazi, Z; Abbasi, L

2017-12-01

peripheral neuropathy is the most common problem of diabetes. Neuropathy leads to lower extremity somatosensory deficits and postural instability in these patients. However, there are not sufficient evidences for improving postural control in these patients. To investigate the effects of transcutaneous electrical nerve stimulation (TENS) on postural control in patients with diabetic neuropathy. Twenty eighth patients with diabetic neuropathy (40-55 Y/O) participated in this RCT study. Fourteen patients in case group received TENS and sham TENS was used for control group. Force plate platform was used to extract sway velocity and COP displacement parameters for postural control evaluation. The mean sway velocity and center of pressure displacement along the mediolateral and anteroposterior axes were not significantly different between two groups after TENS application (p>0.05). Application of 5min high frequency TENS on the knee joint could not improve postural control in patients with diabetic neuropathy. Copyright © 2017. Published by Elsevier Ltd.

Breathing pattern and head posture: changes in craniocervical angles.

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Sabatucci, A; Raffaeli, F; Mastrovincenzo, M; Luchetta, A; Giannone, A; Ciavarella, D

2015-04-01

The aim of this study was to observe the influence of oral breathing on head posture and to establish possible postural changes observing the variation of craniocervical angles NSL/OPT and NSL/CVT between oral breathing subjects and physiological breathing subjects. A cross-sectional study was conducted. The sample included 115 subject, 56 boys and 59 girls, 5-22-year-old. Among these, 80 were classified as oral breathers and 35 as physiological breathers. The diagnosis of oral breathing was carried out thanks to characteristic signs and symptoms evaluated on clinical examination, the analysis of characteristic X-ray images, ENT examination with active anterior rhinomanometric (AAR) test. The structural and postural analysis was carried out, calculating the craniofacial angles NSL/OPT and NSL/CVT. Both NSL/OPT and NSL/CVT appear to be significantly greater to those observed in physiological breathing patients. This means that patients who tend to breathe through the mouth rather than exclusively through the nose show a reduction of cervical lordosis and a proinclination of the head. Our study confirms that the oral breathing modifies head position. The significant increase of the craniocervical angles NSL/OPT and NSL/CVT in patients with this altered breathing pattern suggests an elevation of the head and a greater extension of the head compared with the cervical spine. So, to correct the breathing pattern early, either during childhood or during adolescence, can lead to a progressive normalization of craniofacial morphology and head posture.

First-Person Perspective Virtual Body Posture Influences Stress: A Virtual Reality Body Ownership Study

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Bergström, Ilias; Kilteni, Konstantina; Slater, Mel

2016-01-01

In immersive virtual reality (IVR) it is possible to replace a person’s real body by a life-sized virtual body that is seen from first person perspective to visually substitute their own. Multisensory feedback from the virtual to the real body (such as the correspondence of touch and also movement) can also be present. Under these conditions participants typically experience a subjective body ownership illusion (BOI) over the virtual body, even though they know that it is not their real one. In most studies and applications the posture of the real and virtual bodies are as similar as possible. Here we were interested in whether the BOI is diminished when there are gross discrepancies between the real and virtual body postures. We also explored whether a comfortable or uncomfortable virtual body posture would induce feelings and physiological responses commensurate with the posture. We carried out an experiment with 31 participants in IVR realized with a wide field-of-view head-mounted display. All participants were comfortably seated. Sixteen of them were embodied in a virtual body designed to be in a comfortable posture, and the remainder in an uncomfortable posture. The results suggest that the uncomfortable body posture led to lesser subjective BOI than the comfortable one, but that participants in the uncomfortable posture experienced greater awareness of their autonomic physiological responses. Moreover their heart rate, heart rate variability, and the number of mistakes in a cognitive task were associated with the strength of their BOI in the uncomfortable posture: greater heart rate, lower heart rate variability and more mistakes were associated with higher levels of the BOI. These findings point in a consistent direction—that the BOI over a body that is in an uncomfortable posture can lead to subjective, physiological and cognitive effects consistent with discomfort that do not occur with the BOI over a body in a comfortable posture. PMID:26828365

Effects of reduced plantar cutaneous sensation on static postural control in individuals with and without chronic ankle instability.

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Song, Kyeongtak; Kang, Tae Kyu; Wikstrom, Erik A; Jun, Hyung-Pil; Lee, Sae Yong

2017-10-01

The purpose of this study was to determine how reduced plantar cutaneous sensation influences static postural control in individuals with and without CAI. A case-control study design. Twenty-six individuals with self-reported CAI and 26 matched healthy controls participated in this study. The plantar aspect of the participants' foot was then submersed in ice water (0°C) for 10min to reduce plantar sensation. Before and after the cooling procedure, plantar cutaneous sensation thresholds and single leg balance with eyes open and closed were assessed. Significantly, higher scores were observed in both groups after ice water submersion (ppostural control improvement in both groups post-cooling. In single limb balance with eyes closed, Group×Intervention interactions were observed for the TTB AP mean (p=0.003) and TTB AP SD (p=0.017); indicating postural control deficits in CAI group post-cooling, but no changes in the control group. The main finding of this study was that reduced plantar cutaneous sensation induced by an ice submersion procedure caused eyes closed postural control impairments in those with CAI but not healthy controls. The present investigation demonstrated that the ability to dynamically reweight among sensory inputs to maintain postural stability appears to be diminished in CAI patients compared to healthy controls. Copyright © 2016. Published by Elsevier Ltd.

The Effect of Spinal Tap Test on Different Sensory Modalities of Postural Stability in Idiopathic Normal Pressure Hydrocephalus

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Katrin Abram

2016-09-01

Full Text Available Background/Aims: Postural instability in patients with normal pressure hydrocephalus (NPH is a most crucial symptom leading to falls with secondary complications. The aim of the current study was to evaluate the therapeutic effect of spinal tap on postural stability in these patients. Methods: Seventeen patients with clinical symptoms of NPH were examined using gait scale, computerized dynamic posturography (CDP, and neuropsychological assessment. Examinations were done before and after spinal tap test. Results: The gait score showed a significant improvement 24 h after spinal tap test in all subtests and in the sum score (p Conclusion: Postural stability in NPH is predominantly affected by deficient vestibular functions, which did not improve after spinal tap test. Conditions which improved best were mainly independent from visual control and are based on proprioceptive functions.

Influence of deep brain stimulation on postural stability in patients with Parkinson disease

OpenAIRE

Zelenková, Jana

2012-01-01

Parkinson's disease is a neurodegenerative disease of the basal ganglia. Its main symptoms are rigidity, tremor, bradykinesia, hypokinesia and postural instability. One possible way how to infuence diseases is neurosurgical treatment - deep brain stimulation. The principle is the implantation of electrodes in the basal ganglia and modulation of activity of the basal ganglia circuits due to electrical stimulation. Stimulation affects the motor symptoms of Parkinson's disease. This thesis deals...

Cerebral palsy: Influence of TheraTogs ® on gait, posture and in functional performance

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Raquel Ehlert

Full Text Available Abstract Introduction: For children with cerebral palsy, orthoses take an important role in improving posture, gait, functional performance and preventing secondary musculoskeletal disorders. Objective: To evaluate the influence of TheraTogs® on the posture, distribution of plantar pressure during gait and functional performance of a child with spastic diplegia cerebral palsy. Methods: A quantitative evaluation was carried out on a case study in which an 11-year-old child diagnosed with diplegic cerebral palsy underwent postural assessment through the Postural Assessment Software (PAS, plantar pressure distribution assessment during barefoot gait through the Emed-X system, before and after the intervention period of 8 weeks and functional assessment (Pediatric Evaluation of Disability Inventory - PEDI, with and without TheraTogs®. Results: In posture, TheraTogs® had greater influence on hip extension and this change was greater during its use. In the plantar pressure distribution assessment, an increase in posteriorization of plantar pressure occurred in the initial contact, the performance of the push-off phase and initial swing phase improved. In functionality, the child showed improvements in mobility, however, their self-care ability with TheraTogs® was reduced. Conclusion: Although improvements in posture, gait and functionality were verified with the use of TheraTogs®, the excessive heat, difficulties in toileting and self-care were disadvantages in wearing TheraTogs®.

MODIFIED PATH METHODOLOGY FOR OBTAINING INTERVAL-SCALED POSTURAL ASSESSMENTS OF FARMWORKERS.

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Garrison, Emma B; Dropkin, Jonathan; Russell, Rebecca; Jenkins, Paul

2018-01-29

Agricultural workers perform tasks that frequently require awkward and extreme postures that are associated with musculoskeletal disorders (MSDs). The PATH (Posture, Activity, Tools, Handling) system currently provides a sound methodology for quantifying workers' exposure to these awkward postures on an ordinal scale of measurement, which places restrictions on the choice of analytic methods. This study reports a modification of the PATH methodology that instead captures these postures as degrees of flexion, an interval-scaled measurement. Rather than making live observations in the field, as in PATH, the postural assessments were performed on photographs using ImageJ photo analysis software. Capturing the postures in photographs permitted more careful measurement of the degrees of flexion. The current PATH methodology requires that the observer in the field be trained in the use of PATH, whereas the single photographer used in this modification requires only sufficient training to maintain the proper camera angle. Ultimately, these interval-scale measurements could be combined with other quantitative measures, such as those produced by electromyograms (EMGs), to provide more sophisticated estimates of future risk for MSDs. Further, these data can provide a baseline from which the effects of interventions designed to reduce hazardous postures can be calculated with greater precision. Copyright© by the American Society of Agricultural Engineers.

Individual differences in brainstem and basal ganglia structure predict postural control and balance loss in young and older adults.

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Boisgontier, Matthieu P; Cheval, Boris; Chalavi, Sima; van Ruitenbeek, Peter; Leunissen, Inge; Levin, Oron; Nieuwboer, Alice; Swinnen, Stephan P

2017-02-01

It remains unclear which specific brain regions are the most critical for human postural control and balance, and whether they mediate the effect of age. Here, associations between postural performance and corticosubcortical brain regions were examined in young and older adults using multiple structural imaging and linear mixed models. Results showed that of the regions involved in posture, the brainstem was the strongest predictor of postural control and balance: lower brainstem volume predicted larger center of pressure deviation and higher odds of balance loss. Analyses of white and gray matter in the brainstem showed that the pedunculopontine nucleus area appeared to be critical for postural control in both young and older adults. In addition, the brainstem mediated the effect of age on postural control, underscoring the brainstem's fundamental role in aging. Conversely, lower basal ganglia volume predicted better postural performance, suggesting an association between greater neural resources in the basal ganglia and greater movement vigor, resulting in exaggerated postural adjustments. Finally, results showed that practice, shorter height and heavier weight (i.e., higher body mass index), higher total physical activity, and larger ankle active (but not passive) range of motion were predictive of more stable posture, irrespective of age. Copyright © 2016 Elsevier Inc. All rights reserved.

The Neural Basis of Postural Instability Gait Disorder Subtype of Parkinson's Disease: A PET and fMRI Study.

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Zhang, Li; Li, Tian-Nv; Yuan, Yong-Sheng; Jiang, Si-Ming; Tong, Qing; Wang, Min; Wang, Jian-Wei; Chen, Hua-Jun; Ding, Jian; Xu, Qin-Rong; Zhang, Ke-Zhong

2016-05-01

The aim of this study is to further uncover the neural basis of postural instability gait disorder (PIGD) subtype of Parkinson's disease. With F-18 fluorodeoxyglucose PET (FDG-PET), brain glucose metabolism of patients with PIGD (n = 15) was compared with healthy controls (n = 17) and tremor-dominant (TD) patients (n = 15), and the correlation between metabolism and PIGD symptoms was also assessed. Within PIGD symptom-correlated hypometabolic areas, the relationship of functional connectivity (FC) with motor and cognitive symptoms was examined by using functional MRI. Compared with controls, patients with PIGD displayed a distributed pattern of brain hypometabolism including striatal, frontal, and parietal areas. Relative to the pattern of TD patients, the pattern of patients with PIGD had additional metabolic decreases in caudate and inferior parietal lobule (IPL, Brodmann area [BA] 40). In PIGD group, the metabolic reductions in IPL (BA 40), middle frontal gyrus (MFG, BA 9) and fusiform gyrus (FG, BA 20) were associated with severe PIGD symptoms. Regions showing such correlation were chosen for further seed-based FC analysis. Decreased FC within the prefrontal-parietal network (between the MFG and IPL) was associated with severe PIGD symptoms. The involvement of the caudate, FG, and prefrontal-parietal network may be associated with the prominent gait impairments of PIGD subtype. Our findings expand the pathophysiological knowledge of PIGD subtype and provide valuable information for potential neuromodulation therapies alleviating gait disorders. © 2016 John Wiley & Sons Ltd.

Body posture and postural stability of people practicing qigong

Directory of Open Access Journals (Sweden)

Jacek Wilczyński

2015-07-01

Full Text Available Introduction: Correct and stable posture is essential for the implementation of the majority of voluntary movements and locomotion. The study of postural stability is an element of clinical trials evaluating physical activity in order to determine the optimal therapeutic procedures. Qigong exercises are not only a form of prevention, helpful in maintaining wellbeing, but also a means of therapy in many diseases, including disorders of postural stability. Aim of the research: To analyse the association between the quality of posture and postural stability of people practicing qigong. Material and methods : The study involved 32 people. The mean age of those tested was 54 years. Posture study used optoelectronic method Diers formetric III 4D. Postural stability was tested on the platform Biodex Balance System. The studies were performed at the Posture Laboratory of the Institute of Physiotherapy at Jan Kochanowski University in Kielce. Results and conclusions : Spearman rank order correlation showed a positive correlation of relative rotation of the spine area with a general indicator of stability (p = 0.0206 at an average level (R = 0.4075 and with the index of the stability A/P (p = 0.0310, although at a lower level (R = 0.3819. With the increase in the relative rotation of the spine area the overall stability indicator and stability indicator A/P also increased. Significant positive correlations were also seen for the surface rotation (+max and a general indication of the stability and the stability index A/P. With the increase of surface rotation (+max of the spine the overall stability indicator and stability indicator A/P also increased.

Postural control during the Stroop test in dyslexic and non dyslexic teenagers.

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Zoï Kapoula

Full Text Available Postural control in quiet stance although simple still requires some cognitive resources; dual cognitive tasks influence further postural control. The present study examines whether or not dyslexic teenagers experience postural instability when performing a Stroop dual task for which their performances are known to be poor. Fifteen dyslexics and twelve non-dyslexics (14 to 17 years old were recruited from the same school. They were asked to perform three tasks: (1 fixate a target, (2 perform an interference Stroop test (naming the colour or the word rather than reading the word, (3 performing flexibility Stroop task: the subject performed the interference task as in (2 except when the word was in a box, in which case he had to read the word. Postural performances were measured with a force platform. The results showed a main task effect on the variance of speed of body sway only: such variance was higher in the flexibility task than for the other two tasks. No group effect was found for any of the parameters of posture (surface, mediolateral and anteroposterior sway, variance of speed. Further wavelet analysis in the time-frequency domain revealed an increase in the spectral power of the medium frequency range believed to be related to cerebellum control; an accompanying increase in the cancellation time of the high frequency band related to reflexive loops occurred for non-dyslexics only. These effects occurred for the flexibility task and could be due to its high cognitive difficulty. Dyslexics displayed shorter cancellation time for the medium frequency band for all tasks, suggesting less efficient cerebellar control, perhaps of eye fixation and attention influencing body sway. We conclude that there is no evidence for a primary posture deficit in 15 year old teenagers who come from the general population and who were recruited in schools.

Resting State Default Mode Network Connectivity, Dual Task Performance, Gait Speed, and Postural Sway in Older Adults with Mild Cognitive Impairment.

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Crockett, Rachel A; Hsu, Chun Liang; Best, John R; Liu-Ambrose, Teresa

2017-01-01

Aging is associated with an increased risk of falling. In particular, older adults with mild cognitive impairment (MCI) are more vulnerable to falling compared with their healthy counterparts. Major contributors to this increased falls risk include a decline in dual task performance, gait speed, and postural sway. Recent evidence highlights the potential influence of the default mode network (DMN), the frontoparietal network (FPN), and the supplementary motor area (SMA) on dual task performance, gait speed, and postural sway. The DMN is active during rest and deactivates during task-oriented processes, to maintain attention and stay on task. The FPN and SMA are involved in top-down attentional control, motor planning, and motor execution. The DMN shows less deactivation during task in older adults with MCI. This lack of deactivation is theorized to increase competition for resources between the DMN and task-related brain regions (e.g., the FPN and SMA), increasing distraction from the task and reducing task performance. However, no study has yet investigated the relationship between the between-network connectivity of the DMN with these regions and dual task walking, gait speed or postural sway. We hypothesized that greater functional connectivity both within the DMN and between DMN-FPN and DMN-SMA, will be associated with poorer performance during dual task walking, slower gait speed, and greater postural sway in older adults with MCI. Forty older adults with MCI were measured on a dual task-walking paradigm, gait speed over a 4-m walk, and postural sway using a sway-meter. Greater within-DMN connectivity was significantly correlated with poorer dual task performance. Furthermore, greater inter-network connectivity between the DMN and SMA was significantly correlated with slower gait speed and greater postural sway on the eyes open floor sway task. Thus, greater resting state DMN functional connectivity may be an underlying neural mechanism for reduced dual task

Chronic Low Quality Sleep Impairs Postural Control in Healthy Adults.

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Furtado, Fabianne; Gonçalves, Bruno da Silva B; Abranches, Isabela Lopes Laguardia; Abrantes, Ana Flávia; Forner-Cordero, Arturo

2016-01-01

The lack of sleep, both in quality and quantity, is an increasing problem in modern society, often related to workload and stress. A number of studies have addressed the effects of acute (total) sleep deprivation on postural control. However, up to date, the effects of chronic sleep deficits, either in quantity or quality, have not been analyzed. Thirty healthy adults participated in the study that consisted of registering activity with a wrist actigraph for more than a week before performing a series of postural control tests. Sleep and circadian rhythm variables were correlated and the sum of activity of the least active 5-h period, L5, a rhythm variable, obtained the greater coefficient value with sleep quality variables (wake after sleep onset WASO and efficiency sleep). Cluster analysis was performed to classify subjects into two groups based on L5 (low and high). The balance tests scores used to asses postural control were measured using Biodex Balance System and were compared between the two groups with different sleep quality. The postural tests were divided into dynamic (platform tilt with eyes open, closed and cursor) and static (clinical test of sensory integration). The results showed that during the tests with eyes closed, the group with worse sleep quality had also worse postural control performance. Lack of vision impairs postural balance more deeply in subjects with chronic sleep inefficiency. Chronic poor sleep quality impairs postural control similarly to total sleep deprivation.

Chronic Low Quality Sleep Impairs Postural Control in Healthy Adults.

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Fabianne Furtado

Full Text Available The lack of sleep, both in quality and quantity, is an increasing problem in modern society, often related to workload and stress. A number of studies have addressed the effects of acute (total sleep deprivation on postural control. However, up to date, the effects of chronic sleep deficits, either in quantity or quality, have not been analyzed. Thirty healthy adults participated in the study that consisted of registering activity with a wrist actigraph for more than a week before performing a series of postural control tests. Sleep and circadian rhythm variables were correlated and the sum of activity of the least active 5-h period, L5, a rhythm variable, obtained the greater coefficient value with sleep quality variables (wake after sleep onset WASO and efficiency sleep. Cluster analysis was performed to classify subjects into two groups based on L5 (low and high. The balance tests scores used to asses postural control were measured using Biodex Balance System and were compared between the two groups with different sleep quality. The postural tests were divided into dynamic (platform tilt with eyes open, closed and cursor and static (clinical test of sensory integration. The results showed that during the tests with eyes closed, the group with worse sleep quality had also worse postural control performance. Lack of vision impairs postural balance more deeply in subjects with chronic sleep inefficiency. Chronic poor sleep quality impairs postural control similarly to total sleep deprivation.

Motor deficits in schizophrenia quantified by nonlinear analysis of postural sway.

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Jerillyn S Kent

Full Text Available Motor dysfunction is a consistently reported but understudied aspect of schizophrenia. Postural sway area was examined in individuals with schizophrenia under four conditions with different amounts of visual and proprioceptive feedback: eyes open or closed and feet together or shoulder width apart. The nonlinear complexity of postural sway was assessed by detrended fluctuation analysis (DFA. The schizophrenia group (n = 27 exhibited greater sway area compared to controls (n = 37. Participants with schizophrenia showed increased sway area following the removal of visual input, while this pattern was absent in controls. Examination of DFA revealed decreased complexity of postural sway and abnormal changes in complexity upon removal of visual input in individuals with schizophrenia. Additionally, less complex postural sway was associated with increased symptom severity in participants with schizophrenia. Given the critical involvement of the cerebellum and related circuits in postural stability and sensorimotor integration, these results are consistent with growing evidence of motor, cerebellar, and sensory integration dysfunction in the disorder, and with theoretical models that implicate cerebellar deficits and more general disconnection of function in schizophrenia.

Risk factors associated with structural postural changes in the spinal column of children and adolescents

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Juliana Adami Sedrez

2015-03-01

Full Text Available OBJECTIVE: To investigate the association between behavioral risk factors, specifically postural habits, with the presence of structural changes in the spinal column of children and adolescents. METHODS: 59 students were evaluated through the self-reporting Back Pain and Body Posture Evaluation Instrument and spinal panoramic radiographic examination. Spine curvatures were classified based on Cobb angles, as normal or altered in the saggital plane and as normal or scoliotic in the frontal plane. Data were analyzed using SPSS 18.0, based on descriptive statistics and chi-square association test (a=0,05. RESULTS: The prevalence of postural changes was 79.7% (n=47, of which 47.5% (n=28 showed frontal plane changes and 61% (n=36 sagital plane changes. Significant association was found between the presence of thoracic kyphosis and female gender, practice of physical exercises only once or twice a week, sleep time greater than 10 hours, inadequate postures when sitting on a seat and sitting down to write, and how school supplies are carried. Lumbar lordosis was associated with the inadequate way of carrying the school backpack (asymmetric; and scoliosis was associated wuth the practice of competitive sports and sleep time greater than 10 hours. CONCLUSIONS: Lifestyle may be associated with postural changes. It is important to develop health policies in order to reduce the prevalence of postural changes, by decreasing the associated risk factors.

Body surface posture evaluation: construction, validation and protocol of the SPGAP system (Posture evaluation rotating platform system).

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Schwertner, Debora Soccal; Oliveira, Raul; Mazo, Giovana Zarpellon; Gioda, Fabiane Rosa; Kelber, Christian Roberto; Swarowsky, Alessandra

2016-05-04

Several posture evaluation devices have been used to detect deviations of the vertebral column. However it has been observed that the instruments present measurement errors related to the equipment, environment or measurement protocol. This study aimed to build, validate, analyze the reliability and describe a measurement protocol for the use of the Posture Evaluation Rotating Platform System (SPGAP, Brazilian abbreviation). The posture evaluation system comprises a Posture Evaluation Rotating Platform, video camera, calibration support and measurement software. Two pilot studies were carried out with 102 elderly individuals (average age 69 years old, SD = ±7.3) to establish a protocol for SPGAP, controlling the measurement errors related to the environment, equipment and the person under evaluation. Content validation was completed with input from judges with expertise in posture measurement. The variation coefficient method was used to validate the measurement by the instrument of an object with known dimensions. Finally, reliability was established using repeated measurements of the known object. Expert content judges gave the system excellent ratings for content validity (mean 9.4 out of 10; SD 1.13). The measurement of an object with known dimensions indicated excellent validity (all measurement errors reality. To verify the images of objects with known dimensions the values for the width and height were, respectively, CV 0.88 (width) and 2.33 (height), SD 0.22 (width) and 0.35 (height), minimum and maximum values 24.83-25.2 (width) and 14.56 - 15.75 (height). In the analysis of different images (similar) of an individual, greater discrepancies were observed in the values found. The cervical index, for example, presented minimum and maximum values of 15.38 and 37.5, a coefficient of variation of 0.29 and a standard deviation of 6.78. The SPGAP was shown to be a valid and reliable instrument for the quantitative analysis of body posture with applicability and

What is the most effective posture to conduct vibration from the lower to the upper extremities during whole-body vibration exercise?

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Tsukahara Y

2016-01-01

Full Text Available Yuka Tsukahara, Jun Iwamoto, Kosui Iwashita, Takuma Shinjo, Koichiro Azuma, Hideo MatsumotoInstitute for Integrated Sports Medicine, Keio University School of Medicine, Tokyo, Japan Background: Whole-body vibration (WBV exercise is widely used for training and rehabilitation. However, the optimal posture for training both the upper and lower extremities simultaneously remains to be established. Objectives: The objective of this study was to search for an effective posture to conduct vibration from the lower to the upper extremities while performing WBV exercises without any adverse effects. Methods: Twelve healthy volunteers (age: 22–34 years were enrolled in the study. To measure the magnitude of vibration, four accelerometers were attached to the upper arm, back, thigh, and calf of each subject. Vibrations were produced using a WBV platform (Galileo 900 with an amplitude of 4 mm at two frequencies, 15 and 30 Hz. The following three postures were examined: posture A, standing posture with the knees flexed at 30°; posture B, crouching position with no direct contact between the knees and elbows; and posture C, crouching position with direct contact between the knees and elbows. The ratio of the magnitude of vibration at the thigh, back, and upper arm relative to that at the calf was used as an index of vibration conduction. Results: Posture B was associated with a greater magnitude of vibration to the calf than posture A at 15 Hz, and postures B and C were associated with greater magnitudes of vibration than posture A at 30 Hz. Posture C was associated with a vibration conduction to the upper arm that was 4.62 times and 8.26 times greater than that for posture A at 15 and 30 Hz, respectively. Conclusion: This study revealed that a crouching position on a WBV platform with direct contact between the knees and elbows was effective for conducting vibration from the lower to the upper extremities. Keywords: whole-body vibration exercise, upper

Differential effect of environmental risk factors on postural instability gait difficulties and tremor dominant Parkinson's disease.

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Skeie, G O; Muller, B; Haugarvoll, K; Larsen, J P; Tysnes, O B

2010-09-15

Both environmental and genetic factors contribute to the development of Parkinson's disease (PD). We have examined environmental risk factors in a Norwegian population of incident PD patients and controls, the Norwegian ParkWest study. All five neurological wards in the study area of Western Norway participated in the study. A 4-step diagnostic procedure was used to establish a representative cohort of patients with incident PD at a high level of diagnostic accuracy. 212 incident PD patients and 175 age- and gender-matched controls were included. PD patients and controls were asked for information on occupation, education, exposure to pesticides, tobacco, alcohol, and caffeine. Agricultural work was associated with a higher risk of PD (OR 1.75 (1.03-3.0) P = 0.009). There were no differences as to other occupations. Smoking (OR 0.63 (0.42-0.95) P = 0.016) and alcohol use (OR 0.55 P = 0.008) were associated with a lower risk for PD. Interestingly, this inverse association was only seen in postural instability gait difficulties (PIGD) PD (P = 0.046 for smoking, P = 0.07 for alcohol consumption), and not in tremor dominant (TD) PD which was similar to controls. Consumption of coffee was lower in PD patients (3.3 ± 1.8 cups per day vs. 3.8 ± 2.0 in controls P = 0.02). In the regression model including intake of alcohol, coffee, and smoke, only coffee (P = 0.007) and alcohol intake (P = 0.021) remained significant whereas smoking was no longer significant. Thus, it seems as though only coffee intake reduces the risk of PD in general while associations to alcohol and smoking differ between PIGD and TD-PD patients. © 2010 Movement Disorder Society.

Investigation of postural edema in the lower extremities of traffic control workers

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Ana Paula Nunes Pereira Brito

2013-12-01

Full Text Available OBJECTIVE: Determine the prevalence of postural edema and investigate whether working posture - sitting down or standing up - affect its frequency. METHODS: Sixteen traffic control agents were assessed by water displacement volumetry and the results were analyzed in two groups, depending on working posture. Those who worked standing up for more than 4 hours were allocated to the SU group and those who worked sitting down for more than 4 hours were allocated to the SD group. Each worker was assessed before and after their working shift for three consecutive days. Data were analyzed using ANOVA and the test of equality of two proportions. The significance level was set at p ≤ 0.05. The assessment showed that members of both groups had postural edema of the lower extremities (p ≤ 0.001. RESULTS: When the frequency of postural edema was compared across groups, a trend was observed for greater edema formation in the SU group than in the SD group, although without statistically significant difference. CONCLUSION: It was concluded that traffic control agents suffer postural edema after 4 hours working in either of the postures investigated although with a predominance of edema formation among those who work standing up.

Effect of fibular repositioning taping in adult basketball players with chronic ankle instability: a randomized, placebo-controlled, crossover trial.

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Alves, Yanina; Ribeiro, Fernando; Silva, Anabela G

2017-07-05

Chronic ankle instability presents a high incidence and prevalence in basketbal players. It's important to develop strategies to reduce the functional and mechanical limitations resulting from this condition. To compare the effect of Mulligan ́s fibular repositioning taping with a placebo taping immediatly after application and after a running test (Yo-Yo IRT). 16 adult basketball players (10 male, 6 female) with chronic ankle instability and mean age 21.50 ± 2.76 years old. Assessment of static postural control (15 seconds of unipedal stance test with eyes closed in a force platform), functional performance (figure 8 hop test and lateral hop test) and neuromuscular control (peroneus longus latency time in sudden inversion) in two conditions: Mulligan and Placebo. No significant effect was found for the intervantion factor in both hop tests (p>0.170), but there was a significant effect for the time factor (p<0.03). For the peroneus longus latency time, there was a significant interaction between factors (p=0.028) and also for time (p=0.042). No significant effect was found for any of the static postural control variables (area, speed and total displacement) (p≥0.10). There was no differences between Mulligan's fibular repositioning taping and Placebo taping in postural control and functional performance in basketball players with chronic ankle instability. However, Mulligan's taping appears to reduce peroneus longus latency time after a running when compared with a placebo taping.

Posture, head stability, and orientation recovery during vestibular regeneration in pigeons.

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Dickman, J David; Lim, Insook

2004-09-01

Compensatory behavior such as oculomotor, gaze, and postural responses that occur during movement largely depend upon a functioning vestibular system. In the present study, the initial loss and subsequent recovery of postural and head stability in pigeons undergoing vestibular regeneration were examined. Adult pigeons were trained to manipulate a straight run chamber to peck an illuminated key for fluid reward. Six behavioral measures assessing performance, posture, and head stability were quantified. These included run latency, steps (walking), path negotiation (lane changes), gaze saccades, head bobs, and head shakes. Once normative values were obtained for four birds, complete lesion of all receptor cells and denervation of the epithelia in the vestibular endorgans were produced using a single intralabyrinthine application of streptomycin sulfate. Each bird was then tested at specific times during regeneration and the same behavioral measures examined. At 7 days post-streptomycin treatment (PST), all birds exhibited severe postural and head instability, with tremors, head shakes, staggering, and circling predominating. No normal trial runs, walking, gaze saccades, or head bobs were present. Many of these dysfunctions persisted through 3-4 weeks PST. Gradually, tremor and head shakes diminished and were replaced with an increasing number of normal head bobs during steps and gaze saccades. Beginning at 4 weeks PST, but largely inaccurate, was the observed initiation of directed steps, less staggering, and some successful path negotiation. As regeneration progressed, spatial orientation and navigation ability increased and, by 49 days PST, most trials were successful. By 70 days PST, all birds had recovered to pretreatment levels. Thus, it was observed that ataxia must subside, coincident with normalized head and postural stability prior to the recovery of spatial orientation and path navigation recovery. Parallels in recovery were drawn to hair cell regeneration

STATIC AND DYNAMIC POSTURE CONTROL IN POSTLINGUAL COCHLEAR IMPLANTED PATIENTS: Effects of dual-tasking, visual and auditory inputs suppression

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BERNARD DEMANZE eLaurence

2014-01-01

Full Text Available Posture control is based on central integration of multisensory inputs, and on internal representation of body orientation in space. This multisensory feedback regulates posture control and continuously updates the internal model of body’s position which in turn forwards motor commands adapted to the environmental context and constraints. The peripheral localization of the vestibular system, close to the cochlea, makes vestibular damage possible following cochlear implant (CI surgery. Impaired vestibular function in CI patients, if any, may have a strong impact on posture stability. The simple postural task of quiet standing is generally paired with cognitive activity in most day life conditions, leading therefore to competition for attentional resources in dual-tasking, and increased risk of fall particularly in patients with impaired vestibular function. This study was aimed at evaluating the effects of post-lingual cochlear implantation on posture control in adult deaf patients. Possible impairment of vestibular function was assessed by comparing the postural performance of patients to that of age-matched healthy subjects during a simple postural task performed in static and dynamic conditions, and during dual-tasking with a visual or auditory memory task. Postural tests were done in eyes open (EO and eyes closed (EC conditions, with the cochlear implant activated (ON or not (OFF. Results showed that the CI patients significantly reduced limits of stability and increased postural instability in static conditions. In dynamic conditions, they spent considerably more energy to maintain equilibrium, and their head was stabilized neither in space nor on trunk while the controls showed a whole body rigidification strategy. Hearing (prosthesis on as well as dual-tasking did not really improve the dynamic postural performance of the CI patients. We conclude that CI patients become strongly visual dependent mainly in challenging postural conditions.

The role of Postural instability/gait difficulty and Fear of falling in predicting falls in non-demented older adults

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Allali, Gilles; Ayers, Emmeline I.; Holtzer, Roee; Verghese, Joe

2016-01-01

Introduction Postural instability/gait difficulty (PIGD) and fear of falling (FoF) frequently co-exist, but their individual predictive values for falls have not been compared in aging. This study aims to determine both independent and combined effect of PIGD and FoF to falls in older adults without dementia. Methods PIGD and other extrapyramidal signs were systematically assessed in 449 community-dwelling participants without Parkinson’s disease (76.48 ± 6.61 ys; 56.8% female) enrolled in this longitudinal cohort study. Presence of FoF was measured by a single-item question (Do you have a FoF?) and self-confidence by the Activities-specific Balance Confidence scale (ABC scale). Results One hundred sixty-nine participants (38 %) had an incident fall over a mean follow-up of 20.1 ± 12.2 months. PIGD was present in 32% and FoF in 23% of the participants. Both PIGD (adjusted hazard ratio (aHR): 2.28; p = 0.016) and self-confidence (aHR: 0.99; p = 0.040) predicted falls when entered simultaneously in the Cox model. However, presence of FoF (aHR: 1.99; p = 0.021) and self-confidence (aHR: 0.98; p = 0.006) predicted falls only in individuals with PIGD. Conclusions PIGD and FoF were associated with future falls in older adults without dementia but FoF was a fall’s predictor only in individuals with PIGD. PMID:27866086

Benefit of bi-ocular visual stimulation for postural control in children with strabismus.

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Gaertner, Chrystal; Creux, Charlotte; Espinasse-Berrod, Marie-Andrée; Orssaud, Christophe; Dufier, Jean-Louis; Kapoula, Zoï

2013-01-01

Vision is important for postural control as is shown by the Romberg quotient (RQ): with eyes closed, postural instability increases relative to eyes open (RQ = 2). Yet while fixating at far distance, postural stability is similar with eyes open and eyes closed (RQ = 1). Postural stability can be better with both eyes viewing than one eye, but such effect is not consistent among healthy subjects. The first goal of the study is to test the RQ as a function of distance for children with convergent versus divergent strabismus. The second goal is to test whether vision from two eyes relative to vision from one eye provides better postural stability. Thirteen children with divergent strabismus and eleven with convergent strabismus participated in this study. Posturtography was done with the Techno concept device. Experiment 1, four conditions: fixation at 40 cm and at 200 cm both with eyes open and eyes covered (evaluation of RQ). Experiment 2, six conditions: fixation at 40 cm and at 200 cm, with both eyes viewing or under monocular vision (dominant and non-dominant eye). For convergent strabismus, the groups mean value of RQ was 1.3 at near and 0.94 at far distance; for divergent, it was 1.06 at near and 1.68 at far. For all children, the surface of body sway was significantly smaller under both eyes viewing than monocular viewing (either eye). Increased RQ value at near for convergent and at far for divergent strabismus is attributed to the influence of the default strabismus angle and to better use of ocular motor signals. Vision with the two eyes improves postural control for both viewing distances and for both types of strabismus. Such benefit can be due to complementary mechanisms: larger visual field, better quality of fixation and vergence angle due to the use of visual inputs from both eyes.

Relation between risk of falling and postural sway complexity in diabetes.

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Morrison, S; Colberg, S R; Parson, H K; Vinik, A I

2012-04-01

For older individuals with diabetes, any decline in balance control can be especially problematic since it is often a precursor to an increased risk of falling. This study was designed to evaluate differences in postural motion dynamics and falls risk for older individuals with type 2 diabetes (T2DM) classified as fallers/non-fallers and, to assess what impact exercise has on balance and falls risk. The results demonstrated that the risk of falling is greater for those older individuals with multiple risk factors including diabetes and a previous falls history. The postural motion features of the high-risk individuals (T2DM-fallers) were also different, being characterized by increased variability and complexity, increased AP-ML coupling, less overall COP motion and increased velocity. One suggestion is that these individuals evoked a stiffening strategy during the more challenging postural tasks. Following training, a decline in falls risk was observed for all groups, with this effect being most pronounced for the T2DM-fallers. Interestingly, the COP motion of this group became more similar to controls, exhibiting decreased complexity and variability, and decreased velocity. The reciprocal changes in COP complexity support the broader view that age/disease-related changes in physiological complexity are bi-directional. Overall, these results show that, even for older T2DM individuals at greater risk of falling, targeted interventions can positively enhance their postural dynamics. Further, the finding that the pattern of postural motion variability and complexity was altered highlights that a decline in physiological complexity may not always be negatively associated with aging and/or disease. Copyright © 2011 Elsevier B.V. All rights reserved.

Visual Information and Support Surface for Postural Control in Visual Search Task.

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Huang, Chia-Chun; Yang, Chih-Mei

2016-10-01

When standing on a reduced support surface, people increase their reliance on visual information to control posture. This assertion was tested in the current study. The effects of imposed motion and support surface on postural control during visual search were investigated. Twelve participants (aged 21 ± 1.8 years; six men and six women) stood on a reduced support surface (45% base of support). In a room that moved back and forth along the anteroposterior axis, participants performed visual search for a given letter in an article. Postural sway variability and head-room coupling were measured. The results of head-room coupling, but not postural sway, supported the assertion that people increase reliance on visual information when standing on a reduced support surface. Whether standing on a whole or reduced surface, people stabilized their posture to perform the visual search tasks. Compared to a fixed target, searching on a hand-held target showed greater head-room coupling when standing on a reduced surface. © The Author(s) 2016.

Postural orientation and equilibrium processes associated with increased postural sway in autism spectrum disorder (ASD).

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Wang, Zheng; Hallac, Rami R; Conroy, Kaitlin C; White, Stormi P; Kane, Alex A; Collinsworth, Amy L; Sweeney, John A; Mosconi, Matthew W

2016-01-01

Increased postural sway has been repeatedly documented in children with autism spectrum disorder (ASD). Characterizing the control processes underlying this deficit, including postural orientation and equilibrium, may provide key insights into neurophysiological mechanisms associated with ASD. Postural orientation refers to children's ability to actively align their trunk and head with respect to their base of support, while postural equilibrium is an active process whereby children coordinate ankle dorsi-/plantar-flexion and hip abduction/adduction movements to stabilize their upper body. Dynamic engagement of each of these control processes is important for maintaining postural stability, though neither postural orientation nor equilibrium has been studied in ASD. Twenty-two children with ASD and 21 age and performance IQ-matched typically developing (TD) controls completed three standing tests. During static stance, participants were instructed to stand as still as possible. During dynamic stances, participants swayed at a comfortable speed and magnitude in either anterior-posterior (AP) or mediolateral (ML) directions. The center of pressure (COP) standard deviation and trajectory length were examined to determine if children with ASD showed increased postural sway. Postural orientation was assessed using a novel virtual time-to-contact (VTC) approach that characterized spatiotemporal dimensions of children's postural sway (i.e., body alignment) relative to their postural limitation boundary, defined as the maximum extent to which each child could sway in each direction. Postural equilibrium was quantified by evaluating the amount of shared or mutual information of COP time series measured along the AP and ML directions. Consistent with prior studies, children with ASD showed increased postural sway during both static and dynamic stances relative to TD children. In regard to postural orientation processes, children with ASD demonstrated reduced spatial

Increased dynamic regulation of postural tone through Alexander Technique training.

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Cacciatore, T W; Gurfinkel, V S; Horak, F B; Cordo, P J; Ames, K E

2011-02-01

Gurfinkel and colleagues (2006) recently found that healthy adults dynamically modulate postural muscle tone in the body axis during anti-gravity postural maintenance and that this modulation is inversely correlated with axial stiffness. Our objective in the present study was to investigate whether dynamic modulation of axial postural tone can change through training. We examined whether teachers of the Alexander Technique (AT), who undergo "long-term" (3-year) training, have greater modulation of axial postural tone than matched control subjects. In addition, we performed a longitudinal study on the effect of "short-term" (10-week) AT training on the axial postural tone of individuals with low back pain (LBP), since short term AT training has previously been shown to reduce LBP. Axial postural tone was quantified by measuring the resistance of the neck, trunk and hips to small (±10°), slow (1°/s) torsional rotation during stance. Modulation of tone was determined by the torsional resistance to rotation (peak-to-peak, phase-advance, and variability of torque) and axial muscle activity (EMG). Peak-to-peak torque was lower (∼50%), while phase-advance and cycle-to-cycle variability were enhanced for AT teachers compared to matched control subjects at all levels of the axis. In addition, LBP subjects decreased trunk and hip stiffness following short-term AT training compared to a control intervention. While changes in static levels of postural tone may have contributed to the reduced stiffness observed with the AT, our results suggest that dynamic modulation of postural tone can be enhanced through long-term training in the AT, which may constitute an important direction for therapeutic intervention. Copyright © 2010 Elsevier B.V. All rights reserved.

Body posture modulates action perception.

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Zimmermann, Marius; Toni, Ivan; de Lange, Floris P

2013-04-03

Recent studies have highlighted cognitive and neural similarities between planning and perceiving actions. Given that action planning involves a simulation of potential action plans that depends on the actor's body posture, we reasoned that perceiving actions may also be influenced by one's body posture. Here, we test whether and how this influence occurs by measuring behavioral and cerebral (fMRI) responses in human participants predicting goals of observed actions, while manipulating postural congruency between their own body posture and postures of the observed agents. Behaviorally, predicting action goals is facilitated when the body posture of the observer matches the posture achieved by the observed agent at the end of his action (action's goal posture). Cerebrally, this perceptual postural congruency effect modulates activity in a portion of the left intraparietal sulcus that has previously been shown to be involved in updating neural representations of one's own limb posture during action planning. This intraparietal area showed stronger responses when the goal posture of the observed action did not match the current body posture of the observer. These results add two novel elements to the notion that perceiving actions relies on the same predictive mechanism as planning actions. First, the predictions implemented by this mechanism are based on the current physical configuration of the body. Second, during both action planning and action observation, these predictions pertain to the goal state of the action.

Spatial orientation and postural control in patients with Parkinson's disease.

Science.gov (United States)

Pawlitzki, E; Schlenstedt, C; Schmidt, N; Rotkirch, I; Gövert, F; Hartwigsen, G; Witt, K

2018-02-01

Postural instability is one of the most disabling and risky symptoms of advanced Parkinson's disease (PD). The purpose of this study was to investigate whether and how this is mediated by a centrally impaired spatial orientation. Therefore, we performed a spatial orientation study in 21 PD patients (mean age 68years, SD 8.5 years, 9 women) in a medically on condition and 21 healthy controls (mean age 68.9years, SD 5.5years, 14 women). We compared their spatial responses to the horizontal axis (Sakashita's visual target cancellation task), the vertical axis (bucket-test), the sagittal axis (tilt table test) and postural stability using the Fullerton Advanced Balance Scale (FAB). We found larger deviations on the vertical axis in PD patients, although the direct comparisons of performance in PD patients and healthy controls did not reveal significant differences. While the total scores of the FAB Scale were significantly worse in PD (25.9 points, SD 7.2 points) compared to controls (35.1 points, SD 2.3 points, pbalance control. Copyright © 2017 Elsevier B.V. All rights reserved.

Postural and Balance Disorders in Patients with Parkinson's Disease: A Prospective Open-Label Feasibility Study with Two Months of Action Observation Treatment

Science.gov (United States)

Santamato, Andrea; Ranieri, Maurizio; Cinone, Nicoletta; Stuppiello, Lucia Anna; Valeno, Giovanni; De Sanctis, Jula Laura; Fortunato, Francesca; Solfrizzi, Vincenzo; Greco, Antonio; Seripa, Davide; Panza, Francesco

2015-01-01

Action observation treatment has been proposed as therapeutic option in rehabilitation of patients affected by Parkinson's disease (PD) to improve freezing of gait episodes. The purpose of this prospective open-label feasibility study was to evaluate the impact of 8-week action observation training (video-therapy) for the treatment of postural instability and balance impairment in PD patients. Fifteen PD patients aged under 80 years with scores of 1 to 3 on the Hoehn and Yahr staging and without evidence of freezing of gait were recruited. They underwent 24 sessions of video-therapy training based on carefully watching video clips on motor tasks linked to balance, subsequently performing the same observed movements. No statistically significant differences were observed in the identified outcome measures with the Berg Balance Scale and the Activities-Specific Balance Confidence Scale after two months of follow-up. In the present study, a short course of action observation treatment seems to be not effective in reducing balance impairments and postural instability in patients affected by mild to moderate PD. Further studies with larger samples, longer follow-up period, and standardized protocols of action observation treatment are needed to investigate the effects of this rehabilitation technique in the management of postural and balance disorders of PD patients. PMID:26798551

Relationships between Task-Oriented Postural Control and Motor Ability in Children and Adolescents with Down Syndrome

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Wang, Hui-Yi; Long, I-Man; Liu, Mei-Fang

2012-01-01

Individuals with Down syndrome (DS) have been characterized by greater postural sway in quiet stance and insufficient motor ability. However, there is a lack of studies to explore the properties of dynamic postural sway, especially under conditions of task-oriented movement. The purpose of this study was to investigate the relationships between…

Comparison of posture among adolescent male volleyball players and non-athletes

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Małgorzata Grabara

2014-11-01

Full Text Available Due to high training loads and frequently repeated unilateral exercises, several types of sports training can have an impact on the process of posture development in young athletes. The objective of the study was to assess and compare the postures of adolescent male volleyball players and their non-training peers. The study group comprised 104 volleyball players while the control group consisted of 114 non-training individuals aged 14-16 years. Body posture was assessed by the Moiré method. The volleyball players were significantly taller, and had greater body weight and fat-free mass. The analysis of posture relative to symmetry in the frontal and transverse planes did not show any significant differences between the volleyball players and non-athletes. Postural asymmetries were observed in both the volleyball players and the control participants. Lumbar lordosis was significantly less defined in the volleyball players compared to non-training individuals while no difference was observed in thoracic kyphosis. All athletes demonstrated a loss of lumbar lordosis and an increase in thoracic kyphosis. Significant differences in anteroposterior curvature of the spine between the volleyball players and the non-athletes might be associated with both training and body height. Considering the asymmetric spine overloads which frequently occur in sports training, meticulous posture assessment in young athletes seems well justified.

Comparison of posture among adolescent male volleyball players and non-athlete

Directory of Open Access Journals (Sweden)

Małgorzata Grabara

2014-10-01

Full Text Available Due to high training loads and frequently repeated unilateral exercises, several types of sports training can have an impact on the process of posture development in young athletes. The objective of the study was to assess and compare the postures of adolescent male volleyball players and their non-training peers. The study group comprised 104 volleyball players while the control group consisted of 114 non-training individuals aged 14-16 years. Body posture was assessed by the Moiré method. The volleyball players were significantly taller, and had greater body weight and fat-free mass. The analysis of posture relative to symmetry in the frontal and transverse planes did not show any significant differences between the volleyball players and non-athletes. Postural asymmetries were observed in both the volleyball players and the control participants. Lumbar lordosis was significantly less defined in the volleyball players compared to non-training individuals while no difference was observed in thoracic kyphosis. All athletes demonstrated a loss of lumbar lordosis and an increase in thoracic kyphosis. Significant differences in anteroposterior curvature of the spine between the volleyball players and the non-athletes might be associated with both training and body height. Considering the asymmetric spine overloads which frequently occur in sports training, meticulous posture assessment in young athletes seems well justified.

Comparison of posture among adolescent male volleyball players and non-athletes

Science.gov (United States)

2014-01-01

Due to high training loads and frequently repeated unilateral exercises, several types of sports training can have an impact on the process of posture development in young athletes. The objective of the study was to assess and compare the postures of adolescent male volleyball players and their non-training peers. The study group comprised 104 volleyball players while the control group consisted of 114 non-training individuals aged 14-16 years. Body posture was assessed by the Moiré method. The volleyball players were significantly taller, and had greater body weight and fat-free mass. The analysis of posture relative to symmetry in the frontal and transverse planes did not show any significant differences between the volleyball players and non-athletes. Postural asymmetries were observed in both the volleyball players and the control participants. Lumbar lordosis was significantly less defined in the volleyball players compared to non-training individuals while no difference was observed in thoracic kyphosis. All athletes demonstrated a loss of lumbar lordosis and an increase in thoracic kyphosis. Significant differences in anteroposterior curvature of the spine between the volleyball players and the non-athletes might be associated with both training and body height. Considering the asymmetric spine overloads which frequently occur in sports training, meticulous posture assessment in young athletes seems well justified. PMID:25729154

Forearm posture and mobility in quadrupedal dinosaurs.

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VanBuren, Collin S; Bonnan, Matthew

2013-01-01

Quadrupedality evolved four independent times in dinosaurs; however, the constraints associated with these transitions in limb anatomy and function remain poorly understood, in particular the evolution of forearm posture and rotational ability (i.e., active pronation and supination). Results of previous qualitative studies are inconsistent, likely due to an inability to quantitatively assess the likelihood of their conclusions. We attempt to quantify antebrachial posture and mobility using the radius bone because its morphology is distinct between extant sprawled taxa with a limited active pronation ability and parasagittal taxa that have an enhanced ability to actively pronate the manus. We used a sliding semi-landmark, outline-based geometric morphometric approach of the proximal radial head and a measurement of the angle of curvature of the radius in a sample of 189 mammals, 49 dinosaurs, 35 squamates, 16 birds, and 5 crocodilians. Our results of radial head morphology showed that quadrupedal ceratopsians, bipedal non-hadrosaurid ornithopods, and theropods had limited pronation/supination ability, and sauropodomorphs have unique radial head morphology that likely allowed limited rotational ability. However, the curvature of the radius showed that no dinosaurian clade had the ability to cross the radius about the ulna, suggesting parallel antebrachial elements for all quadrupedal dinosaurs. We conclude that the bipedal origins of all quadrupedal dinosaur clades could have allowed for greater disparity in forelimb posture than previously appreciated, and future studies on dinosaur posture should not limit their classifications to the overly simplistic extant dichotomy.

Forearm posture and mobility in quadrupedal dinosaurs.

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Collin S VanBuren

Full Text Available Quadrupedality evolved four independent times in dinosaurs; however, the constraints associated with these transitions in limb anatomy and function remain poorly understood, in particular the evolution of forearm posture and rotational ability (i.e., active pronation and supination. Results of previous qualitative studies are inconsistent, likely due to an inability to quantitatively assess the likelihood of their conclusions. We attempt to quantify antebrachial posture and mobility using the radius bone because its morphology is distinct between extant sprawled taxa with a limited active pronation ability and parasagittal taxa that have an enhanced ability to actively pronate the manus. We used a sliding semi-landmark, outline-based geometric morphometric approach of the proximal radial head and a measurement of the angle of curvature of the radius in a sample of 189 mammals, 49 dinosaurs, 35 squamates, 16 birds, and 5 crocodilians. Our results of radial head morphology showed that quadrupedal ceratopsians, bipedal non-hadrosaurid ornithopods, and theropods had limited pronation/supination ability, and sauropodomorphs have unique radial head morphology that likely allowed limited rotational ability. However, the curvature of the radius showed that no dinosaurian clade had the ability to cross the radius about the ulna, suggesting parallel antebrachial elements for all quadrupedal dinosaurs. We conclude that the bipedal origins of all quadrupedal dinosaur clades could have allowed for greater disparity in forelimb posture than previously appreciated, and future studies on dinosaur posture should not limit their classifications to the overly simplistic extant dichotomy.

Age-related effects on postural control under multi-task conditions.

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Granacher, Urs; Bridenbaugh, Stephanie A; Muehlbauer, Thomas; Wehrle, Anja; Kressig, Reto W

2011-01-01

Changes in postural sway and gait patterns due to simultaneously performed cognitive (CI) and/or motor interference (MI) tasks have previously been reported and are associated with an increased risk of falling in older adults. The objectives of this study were to investigate the effects of a CI and/or MI task on static and dynamic postural control in young and elderly subjects, and to find out whether there is an association between measures of static and dynamic postural control while concurrently performing the CI and/or MI task. A total of 36 healthy young (n = 18; age: 22.3 ± 3.0 years; BMI: 21.0 ± 1.6 kg/m(2)) and elderly adults (n = 18; age: 73.5 ± 5.5 years; BMI: 24.2 ± 2.9 kg/m(2)) participated in this study. Static postural control was measured during bipedal stance, and dynamic postural control was obtained while walking on an instrumented walkway. Irrespective of the task condition, i.e. single-task or multiple tasks, elderly participants showed larger center-of-pressure displacements and greater stride-to-stride variability than younger participants. Associations between measures of static and dynamic postural control were found only under the single-task condition in the elderly. Age-related deficits in the postural control system seem to be primarily responsible for the observed results. The weak correlations detected between static and dynamic measures could indicate that fall-risk assessment should incorporate dynamic measures under multi-task conditions, and that skills like erect standing and walking are independent of each other and may have to be trained complementarily. Copyright © 2010 S. Karger AG, Basel.

Direct observation of nonequilibrium electroosmotic instability

NARCIS (Netherlands)

Rubinstein, S.M.; Manukyan, G.; Staicu, A.D.; Rubinstein, I.; Zaltzman, B.; Lammertink, Rob G.H.; Mugele, Friedrich Gunther; Wessling, Matthias

2008-01-01

We present a visualization of the predicted instability in ionic conduction from a binary electrolyte into a charge selective solid. This instability develops when a voltage greater than critical is applied to a thin layer of copper sulfate flanked by a copper anode and a cation selective membrane.

Static and dynamic posture control in postlingual cochlear implanted patients: effects of dual-tasking, visual and auditory inputs suppression.

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Bernard-Demanze, Laurence; Léonard, Jacques; Dumitrescu, Michel; Meller, Renaud; Magnan, Jacques; Lacour, Michel

2013-01-01

Posture control is based on central integration of multisensory inputs, and on internal representation of body orientation in space. This multisensory feedback regulates posture control and continuously updates the internal model of body's position which in turn forwards motor commands adapted to the environmental context and constraints. The peripheral localization of the vestibular system, close to the cochlea, makes vestibular damage possible following cochlear implant (CI) surgery. Impaired vestibular function in CI patients, if any, may have a strong impact on posture stability. The simple postural task of quiet standing is generally paired with cognitive activity in most day life conditions, leading therefore to competition for attentional resources in dual-tasking, and increased risk of fall particularly in patients with impaired vestibular function. This study was aimed at evaluating the effects of postlingual cochlear implantation on posture control in adult deaf patients. Possible impairment of vestibular function was assessed by comparing the postural performance of patients to that of age-matched healthy subjects during a simple postural task performed in static (stable platform) and dynamic (platform in translation) conditions, and during dual-tasking with a visual or auditory memory task. Postural tests were done in eyes open (EO) and eyes closed (EC) conditions, with the CI activated (ON) or not (OFF). Results showed that the postural performance of the CI patients strongly differed from the controls, mainly in the EC condition. The CI patients showed significantly reduced limits of stability and increased postural instability in static conditions. In dynamic conditions, they spent considerably more energy to maintain equilibrium, and their head was stabilized neither in space nor on trunk: they behaved dynamically without vision like an inverted pendulum while the controls showed a whole body rigidification strategy. Hearing (prosthesis on) as well

The influence of gravity on regional lung blood flow in humans: SPECT in the upright and head-down posture.

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Ax, M; Sanchez-Crespo, A; Lindahl, S G E; Mure, M; Petersson, J

2017-06-01

Previous studies in humans have shown that gravity has little influence on the distribution of lung blood flow while changing posture from supine to prone. This study aimed to evaluate the maximal influence of posture by comparison of regional lung blood flow in the upright and head-down posture in 8 healthy volunteers, using a tilt table. Regional lung blood flow was marked by intravenous injection of macroaggregates of human albumin labeled with 99m Tc or 113m In, in the upright and head-down posture, respectively, during tidal breathing. Both radiotracers remain fixed in the lung after administration. The distribution of radioactivity was mapped using quantitative single photon emission computed tomography (SPECT) corrected for attenuation and scatter. All images were obtained supine during tidal breathing. A shift from upright to the head-down posture caused a clear redistribution of blood flow from basal to apical regions. We conclude that posture plays a role for the distribution of lung blood flow in upright humans, and that the influence of posture, and thereby gravity, is much greater in the upright and head-down posture than in horizontal postures. However, the results of the study demonstrate that lung structure is the main determinant of regional blood flow and gravity is a secondary contributor to the distribution of lung blood flow in the upright and head-down positions. NEW & NOTEWORTHY Using a dual-isotope quantitative SPECT method, we demonstrated that although a shift in posture redistributes blood flow in the direction of gravity, the results are also consistent with lung structure being a greater determinant of regional blood flow than gravity. To our knowledge, this is the first study to use modern imaging methods to quantify the shift in regional lung blood flow in humans at a change between the upright and head-down postures. Copyright © 2017 the American Physiological Society.

Postural and Balance Disorders in Patients with Parkinson’s Disease: A Prospective Open-Label Feasibility Study with Two Months of Action Observation Treatment

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Andrea Santamato

2015-01-01

Full Text Available Action observation treatment has been proposed as therapeutic option in rehabilitation of patients affected by Parkinson’s disease (PD to improve freezing of gait episodes. The purpose of this prospective open-label feasibility study was to evaluate the impact of 8-week action observation training (video-therapy for the treatment of postural instability and balance impairment in PD patients. Fifteen PD patients aged under 80 years with scores of 1 to 3 on the Hoehn and Yahr staging and without evidence of freezing of gait were recruited. They underwent 24 sessions of video-therapy training based on carefully watching video clips on motor tasks linked to balance, subsequently performing the same observed movements. No statistically significant differences were observed in the identified outcome measures with the Berg Balance Scale and the Activities-Specific Balance Confidence Scale after two months of follow-up. In the present study, a short course of action observation treatment seems to be not effective in reducing balance impairments and postural instability in patients affected by mild to moderate PD. Further studies with larger samples, longer follow-up period, and standardized protocols of action observation treatment are needed to investigate the effects of this rehabilitation technique in the management of postural and balance disorders of PD patients.

Elderly individuals with increased risk of falls show postural balance impairment

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Márcio Rogério de Oliveira

Full Text Available Introduction Falls are a serious public health problem. Objective The aim of this study was to evaluate whether elderly individuals with increased risk of falls have a postural balance deficit, evaluated using a force platform during a one-leg stance. Materials and methods The sample consisted of 94 physically independent elderly individuals from the EELO project. The instruments used were the Downton scale, in order to assess the risk as well as the history of falls, and the force platform to measure postural balance through parameters from the center of pressure (COP. Results Elderly individuals were split into two groups according to the score observed with the Downton scale: G1 — low fall risk (score ≤ 2 — and G2 — high fall risk (score > 2. No differences were observed between the groups concerning gender (P > 0.05, Chi Square test. On the other hand, individuals from G2 showed postural instability when compared to individuals from G1, and individuals from G2 showed higher values in all COP parameters analysed (Mann-Whitney test, P < 0.05. Conclusion It can be concluded that the Downton scale has sensitivity for identifying individuals with balance impairment as well as a risk of falls. Therefore, it may be suggested that this scale may be useful in primary health care for detecting falls in the elderly.

Dual-Task Interference: The Effects of Verbal Cognitive Tasks on Upright Postural Stability in Parkinson's Disease

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J. D. Holmes

2010-01-01

Full Text Available Although dual-task interference has previously been demonstrated to have a significant effect on postural control among individuals with Parkinson's disease, the impact of speech complexity on postural control has not been demonstrated using quantitative biomechanical measures. The postural stability of twelve participants with idiopathic Parkinson's disease and twelve healthy age-matched controls was evaluated under three conditions: (1 without a secondary task, (2 performing a rote repetition task and (3 generating a monologue. Results suggested a significant effect of cognitive load on biomechanical parameters of postural stability. Although both groups increased their postural excursion, individuals with Parkinson's disease demonstrated significantly reduced excursion as compared with that of healthy age-matched controls. This suggests that participants with Parkinson's disease may be overconstraining their postural adjustments in order to focus attention on the cognitive tasks without losing their balance. Ironically, this overconstraint may place the participant at greater risk for a fall.

Interactive effect of body posture on exercise-induced atrial natriuretic peptide release.

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Ray, C A; Delp, M D; Hartle, D K

1990-05-01

The purpose of this investigation was to test the hypothesis that supine exercise elicits a greater atrial natriuretic peptide (ANP) response than upright exercise because of higher atrial filling pressure attained in the supine posture. Plasma ANP concentration ([ANP]) was measured during continuous graded supine and upright exercise in eight healthy men at rest after 4 min of cycling exercise at 31, 51, and 79% of posture-specific peak oxygen uptake (VO2 peak), after 2 min of cycling at posture-specific VO2 peak, and 5 and 15 min postexercise. [ANP] was significantly increased (P less than 0.05) above rest by 64, 140, and 228% during supine cycling at 51 and 79% and VO2 peak, respectively. During upright cycling, [ANP] was significantly increased (P less than 0.05) at 79% (60%) and VO2 peak (125%). After 15 min of postexercise rest, [ANP] remained elevated (P less than 0.05) only in the supine subjects. [ANP] was 63, 79, and 75% higher (P less than 0.05) in the supine than in the upright position during cycling at 51 and 79% and VO2 peak. Systolic, diastolic, and mean blood pressures were not significantly (P greater than 0.05) different between positions in all measurement periods. Heart rates were lower (P less than 0.05) in the supine position compared with the upright position. In conclusion, these results suggest that supine exercise elicits greater ANP release independent of blood pressure and heart rate but presumably caused by greater venous return, central blood volume, and concomitant atrial filling pressure and stretch.

Feeding and resting postures of wild northern muriquis (Brachyteles hypoxanthus).

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Iurck, Maria F; Nowak, Matthew G; Costa, Leny C M; Mendes, Sérgio L; Ford, Susan M; Strier, Karen B

2013-01-01

Increased body size in Brachyteles has been regarded as an important evolutionary adaptation that allowed a greater reliance on leaves compared to other more frugivorous Atelidae, but its association with muriqui positional behavior and substrate use is still unknown. Here, we present original data on the feeding and resting postures of the northern muriqui (Brachyteles hypoxanthus) and evaluate predictions about the relationships between body size, postural behavior, and substrate use derived from previously published data for other atelids (e.g. Alouatta, Ateles, and Lagothrix). The study was undertaken from August 2002 to July 2003 on a large group of well-habituated muriquis inhabiting the Reserva Particular do Patrimônio Natural - Felíciano Miguel Abdala in Minas Gerais, Brazil. Consistent with our predictions, we found that B. hypoxanthus was highly suspensory during postural feeding (60.9%) and commonly used tail-hind limb suspension/horizontal tripod (38.0%) or tail-forelimb/hind limb suspension (21.4%). However, although tail-suspensory postures permitted the muriquis to use the terminal canopy and small-sized substrates, these areas were also accessed via tail-assisted above-branch postural behaviors involving multiple substrates. Unexpectedly, tail-suspensory postures were found to be frequently associated with large substrates, tree trunks, and the understory. We suggest that Brachyteles' ability to access food resources from all areas of a feeding tree and from tree crowns at different canopy levels may account for their ability to efficiently exploit food resources in seasonal disturbed forest fragments of the Brazilian Atlantic Forest today. © 2012 Wiley Periodicals, Inc.

Spinal cord stimulation for the treatment of abnormal posture and gait disorder in patients with Parkinson's disease.

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Agari, Takashi; Date, Isao

2012-01-01

Patients with advanced Parkinson's disease (PD) often present with axial symptoms, including abnormal posture, postural instability, and gait disorder. Although spinal cord stimulation (SCS) is effective for pain, little is known about the effect of SCS on motor function in PD patients. The present study investigated the effect of SCS on posture and gait in 15 PD patients, 5 men and 10 women aged 63-79 years (mean 71.1 years), with low back pain and leg pain who received SCS. A visual analog scale (VAS) was used for pain evaluation pre- and postoperatively. The Unified Parkinson's Disease Rating Scale, Timed Up and Go tests, and Timed 10-Meter Walk tests were used to evaluate motor function and activities of daily living of patients. Preoperative mean VAS score was 8.9 (range 7.8-10), which showed significant postoperative improvement at 3 months to mean VAS score of 2.0 (range 0-3.3). The improvements in VAS scores persisted at 12 months after surgery with mean VAS score of 2.3 (range 0-4). Posture and postural stability motor subscores were improved at 3 months after SCS, and gait had significantly improved at 3 months and 1 year after surgery. Timed 10-Meter Walk tests also demonstrated that patient gait was significantly improved at 3 months and 12 months after surgery. Most advanced stage PD patients suffer considerable pain that causes abnormal posture and gait disturbance. SCS is expected to lead to both amelioration of pain and improvement of motor function in such patients.

An investigation of rugby scrimmaging posture and individual maximum pushing force.

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Wu, Wen-Lan; Chang, Jyh-Jong; Wu, Jia-Hroung; Guo, Lan-Yuen

2007-02-01

Although rugby is a popular contact sport and the isokinetic muscle torque assessment has recently found widespread application in the field of sports medicine, little research has examined the factors associated with the performance of game-specific skills directly by using the isokinetic-type rugby scrimmaging machine. This study is designed to (a) measure and observe the differences in the maximum individual pushing forward force produced by scrimmaging in different body postures (3 body heights x 2 foot positions) with a self-developed rugby scrimmaging machine and (b) observe the variations in hip, knee, and ankle angles at different body postures and explore the relationship between these angle values and the individual maximum pushing force. Ten national rugby players were invited to participate in the examination. The experimental equipment included a self-developed rugby scrimmaging machine and a 3-dimensional motion analysis system. Our results showed that the foot positions (parallel and nonparallel foot positions) do not affect the maximum pushing force; however, the maximum pushing force was significantly lower in posture I (36% body height) than in posture II (38%) and posture III (40%). The maximum forward force in posture III (40% body height) was also slightly greater than for the scrum in posture II (38% body height). In addition, it was determined that hip, knee, and ankle angles under parallel feet positioning are factors that are closely negatively related in terms of affecting maximum pushing force in scrimmaging. In cross-feet postures, there was a positive correlation between individual forward force and hip angle of the rear leg. From our results, we can conclude that if the player stands in an appropriate starting position at the early stage of scrimmaging, it will benefit the forward force production.

Effect of cognitive and motor tasks on postural stability in Parkinson's disease: a posturographic study.

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Marchese, Roberta; Bove, Marco; Abbruzzese, Giovanni

2003-06-01

To analyse the effect of concomitant cognitive or motor task performance on balance control in Parkinson's disease (PD), we performed a posturographic study in 24 PD patients and in 20 sex- and age-matched control subjects. Postural sway was measured with eyes open (EO) and eyes closed (EC) during quiet stance and during performance of calculation or motor sequence of thumb opposition to the other fingers. No difference of centre of foot pressure (COP) parameters was observed during quiet standing (either EO or EC) between patients and controls, but visual deprivation induced in both groups a worsening of postural stability. COP area was significantly increased in PD patients during dual task performance, whereas no difference of COP path and x-y axes was observed. The effects induced by the performance of cognitive or motor task were significantly more evident in PD patients with clinical evidence of postural instability (presence of prior falls in the history). This study demonstrates that dual task interference on postural control can be observed in PD patients during performance of cognitive as well as motor tasks. The balance deterioration during dual task performance was significantly enhanced in patients with history of prior falls. These findings have some implications for the strategies to be used in reducing the risk of fall in PD. Copyright 2003 Movement Disorder Society

Does a crouched leg posture enhance running stability and robustness?

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Blum, Yvonne; Birn-Jeffery, Aleksandra; Daley, Monica A; Seyfarth, Andre

2011-07-21

Humans and birds both walk and run bipedally on compliant legs. However, differences in leg architecture may result in species-specific leg control strategies as indicated by the observed gait patterns. In this work, control strategies for stable running are derived based on a conceptual model and compared with experimental data on running humans and pheasants (Phasianus colchicus). From a model perspective, running with compliant legs can be represented by the planar spring mass model and stabilized by applying swing leg control. Here, linear adaptations of the three leg parameters, leg angle, leg length and leg stiffness during late swing phase are assumed. Experimentally observed kinematic control parameters (leg rotation and leg length change) of human and avian running are compared, and interpreted within the context of this model, with specific focus on stability and robustness characteristics. The results suggest differences in stability characteristics and applied control strategies of human and avian running, which may relate to differences in leg posture (straight leg posture in humans, and crouched leg posture in birds). It has been suggested that crouched leg postures may improve stability. However, as the system of control strategies is overdetermined, our model findings suggest that a crouched leg posture does not necessarily enhance running stability. The model also predicts different leg stiffness adaptation rates for human and avian running, and suggests that a crouched avian leg posture, which is capable of both leg shortening and lengthening, allows for stable running without adjusting leg stiffness. In contrast, in straight-legged human running, the preparation of the ground contact seems to be more critical, requiring leg stiffness adjustment to remain stable. Finally, analysis of a simple robustness measure, the normalized maximum drop, suggests that the crouched leg posture may provide greater robustness to changes in terrain height

Guide to Good Posture

Science.gov (United States)

... you are moving or still, can prevent pain, injuries, and other health problems. What is posture? Posture is how you hold your body. There are two types: Dynamic posture is how you hold yourself when you are moving, like when you are walking, running, or bending over to pick up something. Static ...

Dual task and postural control in Alzheimer's and Parkinson's disease

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Larissa Pires de Andrade

2014-03-01

Full Text Available Patients with neurodegenerative diseases are required to use cognitive resources while maintaining postural control. The aim of this study was to investigate the effects of a frontal cognitive task on postural control in patients with Alzheimer, Parkinson and controls. Thirty-eight participants were instructed to stand upright on a force platform in two experimental conditions: single and dual task. Participants with Parkinson's disease presented an increase in the coefficient of variation greater than 100% in the dual task as compared to the single task for center of pressure (COP area and COP path. In addition, patients with Parkinson's and Alzheimer's disease had a higher number of errors during the execution of the cognitive task when compared to the group of elderly without neurodegenerative diseases. The motor cortex, which is engaged in postural control, does not seem to compete with frontal brain regions in the performance of the cognitive task. However, patients with Parkinson's and Alzheimer's disease presented worsened performance in cognitive task.

Benefit of bi-ocular visual stimulation for postural control in children with strabismus.

Directory of Open Access Journals (Sweden)

Chrystal Gaertner

Full Text Available Vision is important for postural control as is shown by the Romberg quotient (RQ: with eyes closed, postural instability increases relative to eyes open (RQ = 2. Yet while fixating at far distance, postural stability is similar with eyes open and eyes closed (RQ = 1. Postural stability can be better with both eyes viewing than one eye, but such effect is not consistent among healthy subjects. The first goal of the study is to test the RQ as a function of distance for children with convergent versus divergent strabismus. The second goal is to test whether vision from two eyes relative to vision from one eye provides better postural stability. Thirteen children with divergent strabismus and eleven with convergent strabismus participated in this study. Posturtography was done with the Techno concept device. Experiment 1, four conditions: fixation at 40 cm and at 200 cm both with eyes open and eyes covered (evaluation of RQ. Experiment 2, six conditions: fixation at 40 cm and at 200 cm, with both eyes viewing or under monocular vision (dominant and non-dominant eye. For convergent strabismus, the groups mean value of RQ was 1.3 at near and 0.94 at far distance; for divergent, it was 1.06 at near and 1.68 at far. For all children, the surface of body sway was significantly smaller under both eyes viewing than monocular viewing (either eye. Increased RQ value at near for convergent and at far for divergent strabismus is attributed to the influence of the default strabismus angle and to better use of ocular motor signals. Vision with the two eyes improves postural control for both viewing distances and for both types of strabismus. Such benefit can be due to complementary mechanisms: larger visual field, better quality of fixation and vergence angle due to the use of visual inputs from both eyes.

Somatic features and body posture in children with scoliosis and scoliotic posture

Directory of Open Access Journals (Sweden)

Jacek Wilczyński

2017-08-01

Full Text Available Abstract The aim of the study was to evaluate the relationship between somatic features and body posture in children with scoliosis and scoliotic posture. The study included 28 girls aged 7-18 with scoliosis and scoliotic posture. The selection of the subjects was deliberate. Height measurements were conducted with an anthropometer and weight measurements were done with an electronic scale. Body posture tests were performed using Exhibeon 3D digital photogrammetry and digital radiographs. The significant Spearman correlations between postural variables for the sagittal plane and the somatic variables regarded: trunk inclination angle and BMI (R= 0,4553, p= p=0,015, Abs of the trunk inclination angle and BMI (R = 0.5522, p = 0.002, length of thoracic kyphosis and BMI (R=0,4147, p=0.028, lumbar lordosis and BMI (R=0,4509, p=0,016. The significant Spearman correlations between scoliotic posture variables and the somatic variables concerned: length of primary lordosis and body height (R =0,4923, p=0.008, the length of the primary lordosis and body mass (R = 0.3932, p = 0.038, the length of the primary lordosis and BMI (R=0,4923, p=0.008. Variation analysis regarding postural (Exhibeon and somatic variables showed significant correlations between the direction of the primary curvature and body mass (p=0,0432, body height and primary angle location (p=0,0290 and between the height of the body and the location of the secondary angle (p = 0,0278.

SHOULDER EXTERNAL ROTATOR STRENGTH IN RESPONSE TO VARIOUS SITTING POSTURES: A CONTROLLED LABORATORY STUDY.

Science.gov (United States)

Pheasant, Steven; Haydt, Richard; Gottstein, Thomas; Grasso, Anthony; Lombard, Nicholas; Stone, Brandon

2018-02-01

The forward head rounded shoulder (FHRS) sitting posture has been associated with decreased shoulder complex muscle strength and function. Upon clinical observation, the adverse effects of the FHRS sitting posture on shoulder complex isometric muscle strength is also present when testing controls for scapular position. The purpose of the study was to assess the effect of various sitting postures on shoulder external rotator muscle isometric strength when the strength testing controls for scapular position. A cohort study, with subjects serving as their own controls. One hundred subjects ages 20-26 participated in the study. Each subject was placed in a neutral cervical sitting (NCS) posture which was maintained for five minutes after which the strength of the dominant shoulder external rotators was immediately tested with the glenohumeral joint in the neutral position using a Micro-FET3 Hand Held Muscle Testing Dynamometer (HHMTD). Each subject was returned to the NCS posture for subsequent external rotator strength testing after five minutes in a FHRS sitting posture, five additional minutes in the NCS posture and five minutes in a retracted cervical sitting (RCS) posture resulting in each subjects' external rotator strength being tested on four occasions. Subjects were randomized for order between the FHRS and RCS postures. Mean strength values for each condition were normalized to the mean strength value for the 1 st NCS condition for each subject. A statistically significant decline in shoulder external rotator strength following the FHRS sitting posture occurred compared to the appropriate postural conditions (pexternal rotator strength following five minutes in the FHRS sitting posture. The average percentage of strength decline in those with greater than a 10% reduction in external rotator strength was 19%. Sixty-four percent of the subjects experienced less than a 10% decline in shoulder external rotator strength in response to the FHRS sitting posture

Reliability of photogrammetry in the evaluation of the postural aspects of individuals with structural scoliosis.

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Saad, Karen Ruggeri; Colombo, Alexandra Siqueira; Ribeiro, Ana Paula; João, Sílvia Maria Amado

2012-04-01

The purpose of this study was to investigate the reliability of photogrammetry in the measurement of the postural deviations in individuals with idiopathic scoliosis. Twenty participants with scoliosis (17 women and three men), with a mean age of 23.1 ± 9 yrs, were photographed from the posterior and lateral views. The postural aspects were measured with CorelDRAW software. High inter-rater and test-retest reliability indices were found. It was observed that with more severity of scoliosis, greater were the variations between the thoracic kyphosis and lumbar lordosis measures obtained by the same examiner from the left lateral view photographs. A greater body mass index (BMI) was associated with greater variability of the trunk rotation measures obtained by two independent examiners from the right, lateral view (r = 0.656; p = 0.002). The severity of scoliosis was also associated with greater inter-rater variability measures of trunk rotation obtained from the left, lateral view (r = 0.483; p = 0.036). Photogrammetry demonstrated to be a reliable method for the measurement of postural deviations from the posterior and lateral views of individuals with idiopathic scoliosis and could be complementarily employed for the assessment procedures, which could reduce the number of X-rays used for the follow-up assessments of these individuals. Copyright © 2011 Elsevier Ltd. All rights reserved.

Interest of active posturography to detect age-related and early Parkinson's disease-related impairments in mediolateral postural control.

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Bonnet, Cédrick T; Delval, Arnaud; Defebvre, Luc

2014-11-15

Patients with Parkinson's disease display impairments of postural control most particularly in active, challenging conditions. The objective of the present study was to analyze early signs of disease-related and also age-related impairments in mediolateral body extension and postural control. Fifty-five participants (18 Hoehn and Yahr stage 2 patients in the off-drug condition, 18 healthy elderly control subjects, and 19 young adults) were included in the study. The participants performed a quiet stance task and two active tasks that analyzed the performance in mediolateral body motion: a limit of stability and a rhythmic weight shift task. As expected, the patients displayed significantly lower and slower body displacement (head, neck, lower back, center of pressure) than elderly control subjects when performing the two body excursion tasks. However, the behavioral variability in both tasks was similar between the groups. Under these active conditions, the patients showed significantly lower contribution of the hip postural control mechanisms compared with the elderly control subjects. Overall, the patients seemed to lower their performance in order to prevent a mediolateral postural instability. However, these patients, at an early stage of their disease, were not unstable in quiet stance. Complementarily, elderly control subjects displayed slower body performance than young adults, which therefore showed an additional age-related impairment in mediolateral postural control. Overall, the study illustrated markers of age-related and Parkinson's disease impairments in mediolateral postural control that may constrain everyday activities in elderly adults and even more in patients with Parkinson's disease. Copyright © 2014 the American Physiological Society.

Effects of Spaceflight and Hindlimb Suspension on the Posture and Gait of Rats

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Fox, R. A.; Corcoran, M.; Daunton, N. G.; Morey-Holton, E.

1994-01-01

Instability of posture and gait in astronauts following spaceflight (SF) is thought to result from muscle atrophy and from changes in sensory-motor integration in the CNS (central nervous system) that occur during adaptation to microgravity (micro-G). Individuals are thought to have developed, during SF, adaptive changes for the processing of proprioceptive, vestibular and visual sensory inputs with reduced weighting of gravity-based signals and increased weighting of visual and tactile cues. This sensory-motor rearrangement in the CNS apparently occurs to optimize neuromuscular system function for effective movement and postural control in micro-G. However, these adaptive changes are inappropriate for the 1 g environment and lead to disruptions in posture and gait on return to Earth. Few reports are available on the effects of SF on the motor behavior of animals. Rats studied following 18.5 - 19.5 days of SF in the COSMOS program were described as being ..'inert, apathetic, slow'.. and generally unstable. The hindlimbs of these rats were ..'thrust out from the body with fingers pulled apart and the shin unnaturally pronated'. On the 6th postflight day motor behavior was described as similar to that observed in preflight observations. Improved understanding of the mechanisms leading to these changes can be obtained in animal models through detailed analysis of neural and molecular mechanisms related to gait. To begin this process the posture and gait of rats were examined following exposure to either SF or hindlimb suspension (HLS), and during recovery from these conditions.

Absence of rotation perception during warm water caloric irrigation in some seniors with postural instability

OpenAIRE

Elodie eChiarovano; Pierre-Paul eVidal; Christophe eMagnani; Georges eLamas; Ian S Curthoys; Catherine eDe Waele; Catherine eDe Waele

2016-01-01

Falls in seniors are a major public health problem. Falls lead to fear of falling, reduced mobility and decreased quality of life. Vestibular dysfunction is one of the fall risk factors. The relationship between objective measures of vestibular responses and age has been studied. However, the effects of age on vestibular perception during caloric stimulation have not been studied.Twenty senior subjects were included in the study separated in two groups: 10 seniors reporting postural instabili...

Absence of Rotation Perception during Warm Water Caloric Irrigation in Some Seniors with Postural Instability

OpenAIRE

Chiarovano, Elodie; Vidal, Pierre-Paul; Magnani, Christophe; Lamas, Georges; Curthoys, Ian S.; de Waele, Catherine

2016-01-01

Falls in seniors are a major public health problem. Falls lead to fear of falling, reduced mobility, and decreased quality of life. Vestibular dysfunction is one of the fall risk factors. The relationship between objective measures of vestibular responses and age has been studied. However, the effects of age on vestibular perception during caloric stimulation have not been studied. Twenty senior subjects were included in the study, and separated in two groups: 10 seniors reporting postural in...

Postural adaptations to repeated optic flow stimulation in older adults

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O’Connor, Kathryn W.; Loughlin, Patrick J.; Redfern, Mark S.; Sparto, Patrick J.

2008-01-01

The purpose of this study is to understand the processes of adaptation (changes in within-trial postural responses) and habituation (reductions in between-trial postural responses) to visual cues in older and young adults. Of particular interest were responses to sudden increases in optic flow magnitude. The postural sway of 25 healthy young adults and 24 healthy older adults was measured while subjects viewed anterior-posterior 0.4 Hz sinusoidal optic flow for 45 s. Three trials for each of three conditions were performed: 1) constant 12 cm optic flow amplitude (24 cm peak-to-peak), 2) constant 4 cm amplitude (8 cm p-t-p), and 3) a transition in amplitude from 4 to 12 cm. The average power of head sway velocity (Pvel) was calculated for consecutive 5 s intervals during the trial to examine the changes in sway within and between trials. A mixed factor repeated measures ANOVA was performed to examine the effects of subject Group, Trial, and Interval on the Pvel. Pvel was greater in older adults in all conditions (p Pvel of the older adults decreased significantly between all 3 trials, but decreased only between trial 1 and 2 in young adults. While the responses of the young adults to the transition in optic flow from 4 to 12 cm did not significantly change, older adults had an increase in Pvel following the transition, ranging from 6.5 dB for the first trial to 3.4 dB for the third trial. These results show that older adults can habituate to repeated visual perturbation exposures; however, this habituation requires a greater number of exposures than young adults. This suggests aging impacts the ability to quickly modify the relative weighting of the sensory feedback for postural stabilization. PMID:18329878

The Effect of Visual Stimuli on Stability and Complexity of Postural Control

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Haizhen Luo

2018-02-01

Full Text Available Visual input could benefit balance control or increase postural sway, and it is far from fully understanding the effect of visual stimuli on postural stability and its underlying mechanism. In this study, the effect of different visual inputs on stability and complexity of postural control was examined by analyzing the mean velocity (MV, SD, and fuzzy approximate entropy (fApEn of the center of pressure (COP signal during quiet upright standing. We designed five visual exposure conditions: eyes-closed, eyes-open (EO, and three virtual reality (VR scenes (VR1–VR3. The VR scenes were a limited field view of an optokinetic drum rotating around yaw (VR1, pitch (VR2, and roll (VR3 axes, respectively. Sixteen healthy subjects were involved in the experiment, and their COP trajectories were assessed from the force plate data. MV, SD, and fApEn of the COP in anterior–posterior (AP, medial–lateral (ML directions were calculated. Two-way analysis of variance with repeated measures was conducted to test the statistical significance. We found that all the three parameters obtained the lowest values in the EO condition, and highest in the VR3 condition. We also found that the active neuromuscular intervention, indicated by fApEn, in response to changing the visual exposure conditions were more adaptive in AP direction, and the stability, indicated by SD, in ML direction reflected the changes of visual scenes. MV was found to capture both instability and active neuromuscular control dynamics. It seemed that the three parameters provided compensatory information about the postural control in the immersive virtual environment.

Effect of Time after Anterior Cruciate Ligament Tears on Proprioception and Postural Stability.

Directory of Open Access Journals (Sweden)

Dae-Hee Lee

Full Text Available This study was designed to compare proprioception and postural stability in patients with acute (time from injury ≤ 3 months and chronic (time from injury > 3 months ACL tears, and to evaluate the correlation between time interval after ACL injury and proprioception. Thigh muscle strength, postural stability, and joint position sense were compared in 48 patients with acute ACL tears and in 28 with chronic ACL tears. Maximal torque (60°/sec of the quadriceps and hamstring was evaluated using an isokinetic testing device. Postural stability was determined from the anterior-posterior (APSI, medial-lateral (MLSI, and overall (OSI stability indices using stabilometry. Joint position sense was also tested by reproduction of passive positioning (RPP. Muscle strengths and stability indices on both the involved and uninvolved sides were similar in the acute and chronic ACL tear groups. RPP on the involved side was significantly greater in the chronic than in the acute ACL tear group (7.8° vs. 5.6°, P = 0.041. Two of three stability indices (APSI, OSI and RPP were significantly greater on the involved than the uninvolved side in the chronic ACL tear group.

The association of foot arch posture and prior history of shoulder or elbow surgery in elite-level baseball pitchers.

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Feigenbaum, Luis A; Roach, Kathryn E; Kaplan, Lee D; Lesniak, Bryson; Cunningham, Sean

2013-11-01

Case-control. The specific aim of this study was to examine the association between abnormal foot arch postures and a history of shoulder or elbow surgery in baseball pitchers. Pitching a baseball generates forces throughout the musculoskeletal structures of the upper and lower limbs. Structures such as the longitudinal arch of the foot are adaptable to stresses over time. Repeated pitching-related stresses may contribute to acquiring abnormal foot arch postures. Inversely, congenitally abnormal foot arch posture may lead to altered stresses of the upper limb during pitching. A convenience sample of 77 pitchers was recruited from a Division I university team and a professional baseball franchise. Subjects who had a history of shoulder or elbow surgery to the pitching arm were classified as cases. Subjects who met the criteria for classification of pes planus or pes cavus based on longitudinal arch angle were classified as having abnormal foot arch posture. Odds ratios were calculated to examine the association between abnormal foot arch posture and pitching-arm injury requiring surgery. Twenty-three subjects were classified as cases. The odds of being a case were 3.4 (95% confidence interval: 1.2, 9.6; P = .02) times greater for subjects with abnormal foot arch posture and 2.9 (95% confidence interval: 1.0, 8.1; P = .04) times greater for subjects with abnormal foot posture on the lunge leg. Abnormal foot arch posture and a surgical history in the pitching shoulder or elbow may be associated. Because the foot and its arches are adaptable and change over time, the pathomechanics of this association should be further explored.

Collective instabilities of self-gravitating systems, 2

International Nuclear Information System (INIS)

Nakamura, Takashi; Takahara, Fumio; Ikeuchi, Satoru

1975-01-01

The instability modes of rotating self-gravitating systems are investigated on the assumption of infinitely long cylinder. The systems under consideration are a collisionless stellar system with anisotropic velocity dispersion and a gaseous system with anisotropic pressure. In the collisionless stellar system, the Jeans instability mode and the Harris instability mode exist. The dispersion relation is solved numerically and the following results are obtained: the Harris instability occurs even in the region where Wu did not treat, and although its growth rate amounts to the order of angular velocity of the system for sufficient anisotropy, the Harris instability always accompanies the Jeans instability and the latter is always greater than the former in growth rate. In the gaseous system exist the Jeans instability mode and a certain overstable mode, which are different from the Harris instability mode. It is shown that the overstable mode occurs due to coupling of modes. In relation to these results, some problems in galactic structure are discussed. (auth.)

Acute Effects of Posture Shirts on Rounded-Shoulder and Forward-Head Posture in College Students.

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Manor, John; Hibberd, Elizabeth; Petschauer, Meredith; Myers, Joseph

2016-12-01

Rounded-shoulder and forward-head posture can be contributing factors to shoulder pain. Corrective techniques such as manual therapy and exercise have been shown to improve these altered postures, but there is little evidence that corrective garments such as posture shirts can alter posture. To determine the acute effects of corrective postureshirt use on rounded-shoulder and forward-head posture in asymptomatic college students. Repeated-measures intervention study with counterbalanced conditions. Research laboratory. 24 members of the general student body of a university, 18-25 y old, with a forward shoulder angle (FSA) >52° and no history of upper-extremity surgery, scoliosis, active shoulder pain, or shoulder pain in the previous 3 mo that restricted participation for 3 consecutive days. Photographic posture assessment under a control condition, under a sham or treatment condition (counterbalanced), under another control condition, and treatment or sham. FSA and forward head angle (FHA) calculated from a lateral photograph. FSA decreased relative to the control condition while participants wore the sham shirt (P = .029) but not the corrective posture shirt (P = 1.00). FHA was unchanged between groups (P = .371). Application of a corrective posture shirt did not acutely alter FSA or FHA, while application of a sham shirt may decrease FSA at rest.

Neck pain and postural balance among workers with high postural demands - a cross-sectional study

DEFF Research Database (Denmark)

Jørgensen, Marie B.; Skotte, Jørgen H.; Holtermann, Andreas

2011-01-01

Neck pain is related to impaired postural balance among patients and is highly prevalent among workers with high postural demands, for example, cleaners. We therefore hypothesised, that cleaners with neck pain suffer from postural dysfunction. This cross-sectional study tested if cleaners with neck...... pain have an impaired postural balance compared with cleaners without neck pain. Postural balance of 194 cleaners with (n = 85) and without (N = 109) neck pain was studied using three different tests. Success or failure to maintain the standing position for 30 s in unilateral stance was recorded...... to cleaners without neck/low back pain (p balance, measured as CEA (p

The Role of Neuromuscular Changes in Aging and Knee Osteoarthritis on Dynamic Postural Control

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Takacs, Judit; Carpenter, Mark G.; Garland, S. Jayne; Hunt, Michael A.

2013-01-01

Knee osteoarthritis (OA) is a chronic joint condition, with 30% of those over the age of 75 exhibiting severe radiographic disease. Nearly 50% of those with knee OA have experienced a fall in the past year. Falls are a considerable public health concern, with a high risk of serious injury and a significant socioeconomic impact. The ability to defend against a fall relies on adequate dynamic postural control, and alterations in dynamic postural control are seen with normal aging. Neuromuscular changes associated with aging may be responsible for some of these alterations in dynamic postural control. Even greater neuromuscular deficits, which may impact dynamic postural control and the ability to defend against a fall, are seen in people with knee OA. There is little evidence to date on how knee OA affects the ability to respond to and defend against falls and the neuromuscular changes that contribute to balance deficits. As a result, this review will: summarize the key characteristics of postural responses to an external perturbation, highlight the changes in dynamic postural control seen with normal aging, review the neuromuscular changes associated with aging that have known and possible effects on dynamic postural control, and summarize the neuromuscular changes and balance problems in knee OA. Future research to better understand the role of neuromuscular changes in knee OA and their effect on dynamic postural control will be suggested. Such an understanding is critical to the successful creation and implementation of fall prevention and treatment programs, in order to reduce the excessive risk of falling in knee OA. PMID:23696951

The effect of moderate running on foot posture index and plantar pressure distribution in male recreational runners.

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Escamilla-Martínez, Elena; Martínez-Nova, Alfonso; Gómez-Martín, Beatriz; Sánchez-Rodríguez, Raquel; Fernández-Seguín, Lourdes María

2013-01-01

Fatigue due to running has been shown to contribute to changes in plantar pressure distribution. However, little is known about changes in foot posture after running. We sought to compare the foot posture index before and after moderate exercise and to relate any changes to plantar pressure patterns. A baropodometric evaluation was made, using the FootScan platform (RSscan International, Olen, Belgium), of 30 men who were regular runners and their foot posture was examined using the Foot Posture Index before and after a 60-min continuous run at a moderate pace (3.3 m/sec). Foot posture showed a tendency toward pronation after the 60-min run, gaining 2 points in the foot posture index. The total support and medial heel contact areas increased, as did pressures under the second metatarsal head and medial heel. Continuous running at a moderate speed (3.3 m/sec) induced changes in heel strike related to enhanced pronation posture, indicative of greater stress on that zone after physical activity. This observation may help us understand the functioning of the foot, prevent injuries, and design effective plantar orthoses in sport.

The effects of anxiety and external attentional focus on postural control in patients with Parkinson's disease.

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Jazaeri, Seyede Zohreh; Azad, Akram; Mehdizadeh, Hajar; Habibi, Seyed Amirhassan; Mandehgary Najafabadi, Mahbubeh; Saberi, Zakieh Sadat; Rahimzadegan, Hawre; Moradi, Saeed; Behzadipour, Saeed; Parnianpour, Mohamad; Taghizadeh, Ghorban; Khalaf, Kinda

2018-01-01

Although anxiety is a common non-motor outcome of Parkinson's disease (PD) affecting 40% of patients, little attention has been paid so far to its effects on balance impairment and postural control. Improvement of postural control through focusing on the environment (i.e. external focus) has been reported, but the role of anxiety, as a confounding variable, remains unclear. This study aimed to investigate the influence of anxiety and attentional focus instruction on the standing postural control of PD patients. Thirty-four patients with PD (17 with high anxiety (HA-PD) and 17 with low anxiety (LA-PD)), as well as 17 gender- and age-matched healthy control subjects (HC) participated in the study. Postural control was evaluated using a combination of two levels of postural difficulty (standing on a rigid force plate surface with open eyes (RO) and standing on a foam surface with open eyes (FO)), as well as three attentional focus instructions (internal, external and no focus). Only the HA-PD group demonstrated significant postural control impairment as compared to the control, as indicated by significantly greater postural sway measures. Moreover, external focus significantly reduced postural sway in all participants especially during the FO condition. The results of the current study provide evidence that anxiety influences balance control and postural stability in patients with PD, particularly those with high levels of anxiety. The results also confirmed that external focus is a potential strategy that significantly improves the postural control of these patients. Further investigation of clinical applicability is warranted towards developing effective therapeutic and rehabilitative treatment plans.

INFLUENCE OF INJURY ON DYNAMIC POSTURAL CONTROL IN RUNNERS.

Science.gov (United States)

Meardon, Stacey; Klusendorf, Anna; Kernozek, Thomas

2016-06-01

Injury has been linked with altered postural control in active populations. The association between running injury and dynamic postural control has not been examined. The purpose of this study was to examine dynamic postural control in injured and uninjured runners using the Star Excursion Balance Test (SEBT), Time to Stabilization (TTS) of ground reaction forces following a single-leg landing, and postural stability indices reflecting the fluctuations in GRFs during single-leg landing and stabilization tasks (forward and lateral hop). It was hypothesized that dynamic postural control differences would exist between runners with a history of injury that interrupted training for ≥7 days (INJ) when compared to runners without injury (CON). Case-control study. Twenty-two INJ (14 F, 8 M; 23.7 ± 2.1 y; 22.3 ± 2.8 kg/m2; 29.5 ± 16.3 mi/wk) currently running > 50% pre-injury mileage without pain were compared with twenty-two matched CON (14F, 8M; 22.7 ± 1.2 y; 22.7 ± 2.7 kg/m2; 31.2 ± 19.6 mi/wk). INJ group was stratified by site of injury into two groups (Hip/Thigh/Knee and Lower Leg/Ankle/Foot) for secondary analysis. Leg length-normalized anterior, posterolateral, and posteromedial reach distances on the SEBT, medial/lateral and anterior/posterior ground reaction force TTS, directional postural stability indices, and a composite dynamic postural stability index (DPSI), were assessed using mixed model ANOVA (α=0.05) and effect sizes (d). No group X direction interaction or group differences were observed for the SEBT (p=0.51, 0.71) or TTS (p=0.83, 0.72) measures. A group X direction interaction was found for postural stability indices during the forward landing task (ppostural stability index (VPSI) (p=0.01 for both, d=0.80, 0.95) and DPSI (p=0.01, 0.02, d=0.75, 0.93) when compared to CON suggesting impaired balance control. A group X direction interaction was also found for postural stability indices during the lateral landing

Postural control among elderly women with and without osteoporosis: is there a difference?

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Thomaz Nogueira Burke

Full Text Available CONTEXT AND OBJECTIVE: Little is known about postural control among elderly individuals with osteoporosis and its relationship with falls. It has been suggested that elderly women with kyphosis and osteoporosis are at greater risk of falling. The aim of this study was to evaluate posture and postural control among elderly women with and without osteoporosis. DESIGN AND SETTING: Cross-sectional study conducted at the Physical Therapy and Electromyography Laboratory, School of Medicine, Universidade de São Paulo (USP. METHODS: Sixty-six elderly women were selected from the bone metabolism disorders clinic, Division of Rheumatology, USP, and were divided into two groups: osteoporosis and controls, according to their bone mineral density (BMD. Postural control was assessed using the Limits of Stability (LOS test and the Modified Clinical Test of Sensory Interaction and Balance (CTSIBm and posture, using photometry. RESULTS: The elderly women with osteoporosis swayed at higher velocity on a stable surface with opened eyes (0.30 versus 0.20 degrees/second; P = 0.038. In both groups, the center of pressure (COP was at 30% in the LOS, but with different placements: 156° in the osteoporosis group and 178° in the controls (P = 0.045. Osteoporosis patients fell more than controls did (1.0 versus 0.0; P = 0.036. CONCLUSIONS: The postural control in elderly women with osteoporosis differed from that of the controls, with higher sway velocity and maximum displacement of COP. Despite postural abnormalities such as hyperkyphosis and forward head, the COP position was posteriorized.

The effects of breath alcohol concentration on postural control.

Science.gov (United States)

Fiorentino, Dary D

2018-05-19

Two of the 3 standardized field sobriety tests that U.S. law enforcement uses at roadside checks have a postural equilibrium component to them. Those tests have been validated to detect impairment caused by blood alcohol concentrations (BACs) of 0.08 g/dL or above. Many medical and traffic safety associations support a lower limit, and one state, Utah, has passed a law to lower the limit to 0.05 g/dL. Many studies have examined the effects of alcohol on postural control (of which postural equilibrium is a component), with a consensus emerging that impairment is usually found at BACs greater than 0.06 g/dL. Most of these studies, however, had a relatively small number of subjects, usually between 10 and 30. The current study collected data from a much larger sample. The objective of this study was to provide additional evidence that posture control is negatively affected at BACs greater than 0.06 g/dL or breath alcohol concentrations (BrACs) of 0.06 g/210 L. This was a between-subjects study, with BrAC group as the independent variable (5 levels: 0.00, 0.04, 0.06, 0.08, and 0.10 g/210 L); 4 measures of postural control as the dependent variables; and age, height, and weight as the covariates. Posture control was measured with a force-sensing platform connected to a computer. The feet's center of pressure (CoP) on the platform was recorded and the corresponding movement of the body in the anterior-posterior and lateral planes was derived. Participants (N = 96) were randomly assigned to one of the BrAC groups. Positive BrAC groups were compared to the zero BrAC group. Data were examined with hierarchical multiple regression. Adjusted for age, height, and weight, the main effect of lateral CoP with eyes open was not statistically significant. There was a statistically significant main effect of alcohol on anterior-posterior CoP excursion with eyes open and with eyes closed and lateral CoP excursion with eyes closed. For all 3 of those variables, only BrACs of 0

Postural control deficits in people with fibromyalgia: a pilot study

Science.gov (United States)

2011-01-01

Introduction Postural instability and falls are increasingly recognized problems in patients with fibromyalgia (FM). The purpose of this study was to determine whether FM patients, compared to age-matched healthy controls (HCs), have differences in dynamic posturography, including sensory, motor, and limits of stability. We further sought to determine whether postural instability is associated with strength, proprioception and lower-extremity myofascial trigger points (MTPs); FM symptoms and physical function; dyscognition; balance confidence; and medication use. Last, we evaluated self-reported of falls over the past six months. Methods In this cross-sectional study, we compared middle-aged FM patients and age-matched HCs who underwent computerized dynamic posturography testing and completed the Fibromyalgia Impact Questionnaire-Revised (FIQR) and balance and fall questionnaires. All subjects underwent a neurological and musculoskeletal examination. Descriptive statistics were used to characterize the sample and explore the relationships between variables. The relationships between subjective, clinical and objective variables were evaluated by correlation and regression analyses. Results Twenty-five FM patients and twenty-seven HCs (combined mean age ± standard deviation (SD): 48.6 ± 9.7 years) completed testing. FM patients scored statistically lower on composite sensory organization tests (primary outcome; P < 0.010), as well as with regard to vestibular, visual and somatosensory ratio scores on dynamic posturography. Balance confidence was significantly different between groups, with FM patients reporting less confidence than HCs (mean ± SD: 81.24 ± 19.52 vs. 98.52 ± 2.45; P < 0.001). Interestingly, 76% to 84% of FM patients had gastrocnemius and/or anterior tibialis MTPs. Postural stability was best predicted by dyscognition, FIQR score and body mass index. Regarding falls, 3 (11%) of 27 HCs had fallen only once during the past 6 months, whereas 18 (72

Femoral strength and posture in terrestrial birds and non-avian theropods.

Science.gov (United States)

Farke, Andrew A; Alicea, Justy

2009-09-01

Osteological and experimental evidence suggest a change in femoral posture between non-avian dinosaurs (in which the femur presumably was carried in a subvertical position) and birds (in which the femur is held nearly horizontal during most phases of terrestrial locomotion). In this study, we used a broad comparative sample to test the hypothesis that cross-sectional properties of the femur records evidence of this presumed change in posture. I(max) and I(min) (second moment of area, related to resistance to bending) and cross-sectional area (indicating resistance to compression) were measured from computed tomography scans of the femora of 30 species of flightless or primarily terrestrial birds, one probable non-dinosaur dinosauromorph, and at least four species of non-avian theropods. It was predicted that birds should have more eccentrically shaped femoral midshafts as measured by I(max)/II(min) (reflecting greater bending) and comparatively smaller cross-sectional areas than non-avians. Results show that no significant differences occur between non-avian dinosaurs and birds for any parameter, and the samples overlapped broadly in many cases. Thus, cross-sectional properties cannot be used to infer differences in femoral posture between the two groups. This surprising finding might be explained by the fact that femoral postures were not drastically different or that a gradation of postures occurred in each sample. It is also possible that bone loading during life was not closely correlated with cross-sectional morphology. We conclude that cross-sectional properties should be used with caution in determining the posture and behaviors of extinct animals, and only in conjunction with other morphological information. (c) 2009 Wiley-Liss, Inc.

Should Ballet Dancers Vary Postures and Underfoot Surfaces When Practicing Postural Balance?

Science.gov (United States)

Steinberg, Nili; Waddington, Gordon; Adams, Roger; Karin, Janet; Tirosh, Oren

2018-01-01

Postural balance (PB) is an important component skill for professional dancers. However, the effects of different types of postures and different underfoot surfaces on PB have not adequately been addressed. The main aim of this study was to investigate the effect of different conditions of footwear, surfaces, and standing positions on static and dynamic PB ability of young ballet dancers. A total of 36 male and female young professional ballet dancers (aged 14-19 years) completed static and dynamic balance testing, measured by head and lumbar accelerometers, while standing on one leg in the turnout position, under six different conditions: (1) "relaxed" posture; (2) "ballet" posture; (3) barefoot; (4) ballet shoes with textured insoles; (5) barefoot on a textured mat; and (6) barefoot on a spiky mat. A condition effect was found for static and dynamic PB. Static PB was reduced when dancers stood in the ballet posture compared with standing in the relaxed posture and when standing on a textured mat and on a spiky mat (p ballet shoes with textured insoles and when standing on a spiky mat compared with all other conditions (p ballet aligned position, including dance practice on different types of floors and on different types of textured/spiky materials may result in skill transfer to practice on normal floor surfaces, and both static and dynamic PB exercises should be assessed and generalized into practical dance routines.

Improvement of posture stability by vibratory stimulation following anterior cruciate ligament reconstruction.

Science.gov (United States)

Brunetti, O; Filippi, G M; Lorenzini, M; Liti, A; Panichi, R; Roscini, M; Pettorossi, V E; Cerulli, G

2006-11-01

Surgical reconstruction of the anterior cruciate ligament (ACL) may reduce, but it does not always eliminate, knee and body instability because of a persisting proprioceptive deficit. In order to enhance body stability, a new protocol of treatment has been proposed consisting of mechanical vibration (100 Hz frequency and < 20 microm amplitude) of the quadriceps muscle in the leg that has undergone ACL reconstruction. In our trials, stimulation was performed when the quadriceps muscle was kept isometrically contracted. Treatment was started one month after surgery. Vibration was applied for short periods over three consecutive days. Nine months after treatment, postural stability was re-evaluated with the subjects standing on one leg with open and with closed eyes. The postural stability of the subjects having undergone vibration treatment, standing on the operated leg was significantly improved one day after treatment when evaluated as mean of speed and elliptic area of the center of pressure. The improvement persisted and increased during the following weeks. Peak torques of the operated leg extensor muscles also increased and reached values close to that of the leg, which had not been operated. Conversely, the balance of the untreated subjects standing on the operated leg did not improve and the restoration of the extensor muscle peak torque was poor. It is concluded that short lasting proprioceptive activation by vibration may lead to a faster and more complete equilibrium recovery probably by permanently changing the network controlling knee posture.

Corona-induced electrohydrodynamic instabilities in low conducting liquids

Energy Technology Data Exchange (ETDEWEB)

Vega, F.; Perez, A.T. [Depto. Electronica y Electromagnetismo, Facultad de Fisica, Universidad de Sevilla, Avda. Reina Mercedes, s/n. 41012, Sevilla (Spain)

2003-06-01

The rose-window electrohydrodynamic (EHD) instability has been observed when a perpendicular field with an additional unipolar ion injection is applied onto a low conducting liquid surface. This instability has a characteristic pattern with cells five to 10 times greater than those observed in volume instabilities caused by unipolar injection. We have used corona discharge from a metallic point to perform some measurements of the rose-window instability in low conducting liquids. The results are compared to the linear theoretical criterion for an ohmic liquid. They confirmed that the minimum voltage for this instability is much lower than that for the interfacial instability in high conducting liquids. This was predicted theoretically in the dependence of the critical voltage as a function of the non-dimensional conductivity. It is shown that in a non-ohmic liquid the rose window appears as a secondary instability after the volume instability. (orig.)

Postural Stabilization Differences in Idiopathic Parkinson’s Disease and Progressive Supranuclear Palsy during Self-Triggered Fast Forward Weight Lifting

Directory of Open Access Journals (Sweden)

Stefan Kammermeier

2018-01-01

Full Text Available Progressive supranuclear palsy (PSP and late-stage idiopathic Parkinson’s disease (IPD are neurodegenerative movement disorders resulting in different postural instability and falling symptoms. IPD falls occur usually forward in late stage, whereas PSP falls happen in early stages, mostly backward, unprovoked, and with high morbidity. Self-triggered, weighted movements appear to provoke falls in IPD, but not in PSP. Repeated self-triggered lifting of a 0.5–1-kg weight (<2% of body weight with the dominant hand was performed in 17 PSP, 15 IPD with falling history, and 16 controls on a posturography platform. PSP showed excessive force scaling of weight and body motion with high-frequency multiaxial body sway, whereas IPD presented a delayed-onset forward body displacement. Differences in center of mass displacement apparent at very small weights indicate that both syndromes decompensate postural control already within stability limits. PSP may be subject to specific postural system devolution. IPD are susceptible to delayed forward falling. Differential physiotherapy strategies are suggested.

Effects of affective picture viewing on postural control.

Science.gov (United States)

Stins, John F; Beek, Peter J

2007-10-04

Emotion theory holds that unpleasant events prime withdrawal actions, whereas pleasant events prime approach actions. Recent studies have suggested that passive viewing of emotion eliciting images results in postural adjustments, which become manifest as changes in body center of pressure (COP) trajectories. From those studies it appears that posture is modulated most when viewing pictures with negative valence. The present experiment was conducted to test the hypothesis that pictures with negative valence have a greater impact on postural control than neutral or positive ones. Thirty-four healthy subjects passively viewed a series of emotion eliciting images, while standing either in a bipedal or unipedal stance on a force plate. The images were adopted from the International Affective Picture System (IAPS). We analysed mean and variability of the COP and the length of the associated sway path as a function of emotion. The mean position of the COP was unaffected by emotion, but unipedal stance resulted in overall greater body sway than bipedal stance. We found a modest effect of emotion on COP: viewing pictures of mutilation resulted in a smaller sway path, but only in unipedal stance. We obtained valence and arousal ratings of the images with an independent sample of viewers. These subjects rated the unpleasant images as significantly less pleasant than neutral images, and the pleasant images as significantly more pleasant than neutral images. However, the subjects rated the images as overall less pleasant and less arousing than viewers in a closely comparable American study, pointing to unknown differences in viewer characteristics. Overall, viewing emotion eliciting images had little effect on body sway. Our finding of a reduction in sway path length when viewing pictures of mutilation was indicative of a freezing strategy, i.e. fear bradycardia. The results are consistent with current knowledge about the neuroanatomical organization of the emotion system and

Common postural defects among music students.

Science.gov (United States)

Blanco-Piñeiro, Patricia; Díaz-Pereira, M Pino; Martínez, Aurora

2015-07-01

Postural quality during musical performance affects both musculoskeletal health and the quality of the performance. In this study we examined the posture of 100 students at a Higher Conservatory of Music in Spain. By analysing video tapes and photographs of the students while performing, a panel of experts extracted values of 11 variables reflecting aspects of overall postural quality or the postural quality of various parts of the body. The most common postural defects were identified, together with the situations in which they occur. It is concluded that most students incur in unphysiological postures during performance. It is hoped that use of the results of this study will help correct these errors. Copyright © 2015 Elsevier Ltd. All rights reserved.

Thermoregulatory postures limit antipredator responses in peafowl.

Science.gov (United States)

Yorzinski, Jessica L; Lam, Jennifer; Schultz, Rachel; Davis, Melissa

2018-01-05

Many animals inhabit environments where they experience temperature fluctuations. One way in which animals can adjust to these temperature changes is through behavioral thermoregulation. However, we know little about the thermal benefits of postural changes and the costs they may incur. In this study, we examined the thermoregulatory role of two postures, the head-tuck and leg-tuck posture, in peafowl ( Pavo cristatus ) and evaluated whether the head-tuck posture imposes a predation cost. The heads and legs of peafowl are significantly warmer when the birds exhibit these postures, demonstrating that these postures serve an important thermoregulatory role. In addition, the birds are slower to respond to an approaching threat when they display the head-tuck posture, suggesting that a thermoregulatory posture can limit antipredator behavior. © 2018. Published by The Company of Biologists Ltd.

Thermoregulatory postures limit antipredator responses in peafowl

Directory of Open Access Journals (Sweden)

Jessica L. Yorzinski

2018-01-01

Full Text Available Many animals inhabit environments where they experience temperature fluctuations. One way in which animals can adjust to these temperature changes is through behavioral thermoregulation. However, we know little about the thermal benefits of postural changes and the costs they may incur. In this study, we examined the thermoregulatory role of two postures, the head-tuck and leg-tuck posture, in peafowl (Pavo cristatus and evaluated whether the head-tuck posture imposes a predation cost. The heads and legs of peafowl are significantly warmer when the birds exhibit these postures, demonstrating that these postures serve an important thermoregulatory role. In addition, the birds are slower to respond to an approaching threat when they display the head-tuck posture, suggesting that a thermoregulatory posture can limit antipredator behavior.

Imaging Posture Veils Neural Signals

Directory of Open Access Journals (Sweden)

Robert T Thibault

2016-10-01

Full Text Available Whereas modern brain imaging often demands holding body positions incongruent with everyday life, posture governs both neural activity and cognitive performance. Humans commonly perform while upright; yet, many neuroimaging methodologies require participants to remain motionless and adhere to non-ecological comportments within a confined space. This inconsistency between ecological postures and imaging constraints undermines the transferability and generalizability of many a neuroimaging assay.Here we highlight the influence of posture on brain function and behavior. Specifically, we challenge the tacit assumption that brain processes and cognitive performance are comparable across a spectrum of positions. We provide an integrative synthesis regarding the increasingly prominent influence of imaging postures on autonomic function, mental capacity, sensory thresholds, and neural activity. Arguing that neuroimagers and cognitive scientists could benefit from considering the influence posture wields on both general functioning and brain activity, we examine existing imaging technologies and the potential of portable and versatile imaging devices (e.g., functional near infrared spectroscopy. Finally, we discuss ways that accounting for posture may help unveil the complex brain processes of everyday cognition.

Kinetic theory of tearing instabilities

International Nuclear Information System (INIS)

Drake, J.F.; Lee, Y.C.

1977-01-01

The transition of the tearing instability from the collisional to the collisionless regime is investigated kinetically using a Fokker--Planck collision operator to represent electron-ion collisions. As a function of the collisionality of the plasma, the tearing instability falls into three regions, which are referred to as collisionless, semi-collisional, and collisional. The width Δ of the singular layer around kxB 0 =0 is limited by electron thermal motion along B 0 in the collisional and semi-collisional regimes and is typically smaller than rho/sub i/, the ion Larmor radius. Previously accepted theories, which are based on the assumption Δvery-much-greater-thanrho/sub i/, are found to be valid only in the collisional regime. The effects of density and temperature gradients on the instabilities are also studied. The tearing instability is only driven by the temperature gradient in the collisional and semi-collisional regimes. Numerical calculations indicate that the semi-collisional tearing instability is particularly relevant to present day high temperature tokamak discharges

Postural Coordination during Socio-motor Improvisation.

Science.gov (United States)

Gueugnon, Mathieu; Salesse, Robin N; Coste, Alexandre; Zhao, Zhong; Bardy, Benoît G; Marin, Ludovic

2016-01-01

Human interaction often relies on socio-motor improvisation. Creating unprepared movements during social interaction is not a random process but relies on rules of synchronization. These situations do not only involve people to be coordinated, but also require the adjustment of their posture in order to maintain balance and support movements. The present study investigated posture in such a context. More precisely, we first evaluated the impact of amplitude and complexity of arm movements on posture in solo situation. Then, we assessed the impact of interpersonal coordination on posture using the mirror game in which dyads performed improvised and synchronized movements (i.e., duo situation). Posture was measured through ankle-hip coordination in medio-lateral and antero-posterior directions (ML and AP respectively). Our results revealed the spontaneous emergence of in-phase pattern in ML direction and antiphase pattern in AP direction for solo and duo situations. These two patterns respectively refer to the simultaneous flexion/extension of the ankles and the hips in the same or opposite direction. It suggests different functional roles of postural coordination patterns in each direction, with in-phase supporting task performance in ML (dynamical stability) and antiphase supporting postural control in AP (mechanical stability). Although amplitude of movement did not influence posture, movement complexity disturbed postural stability in both directions. Conversely, interpersonal coordination promoted postural stability in ML but not in AP direction. These results are discussed in terms of the difference in coupling strength between ankle-hip coordination and interpersonal coordination.

Postural coordination during socio-motor improvisation

Directory of Open Access Journals (Sweden)

Mathieu Gueugnon

2016-08-01

Full Text Available Human interaction often relies on socio-motor improvisation. Creating unprepared movements during social interaction is not a random process but relies on rules of synchronization. These situations do not only involve people to be coordinated, but also require the adjustment of their posture in order to maintain balance and support movements. The present study investigated posture in such a context. More precisely, we first evaluated the impact of amplitude and complexity of arm movements on posture in solo situation. Then, we assessed the impact of interpersonal coordination on posture using the mirror game in which dyads performed improvised and synchronized movements (i.e., duo situation. Posture was measured through ankle-hip coordination in medio-lateral and antero-posterior directions (ML and AP respectively. Our results revealed the spontaneous emergence of in-phase pattern in ML direction and anti-phase pattern in AP direction for solo and duo situations. These two patterns respectively refer to the simultaneous flexion/extension of the ankles and the hips in the same or opposite direction. It suggests different functional roles of postural coordination patterns in each direction, with in-phase supporting task performance in ML (dynamical stability and antiphase supporting postural control in AP (mechanical stability. Although amplitude of movement did not influence posture, movement complexity disturbed postural stability in both directions. Conversely, interpersonal coordination promoted postural stability in ML but not in AP direction. These results are discussed in terms of the difference in coupling strength between ankle-hip coordination and interpersonal coordination.

The effect of perindopril on postural instability in older people with a history of falls-a randomised controlled trial.

Science.gov (United States)

Sumukadas, Deepa; Price, Rosemary; McMurdo, Marion E T; Rauchhaus, Petra; Struthers, Allan; McSwiggan, Stephen; Arnold, Graham; Abboud, Rami; Witham, Miles

2018-01-01

double-blind, parallel group, placebo-controlled randomised trial. we recruited people aged >65 years with at least one fall in the previous year. Participants received 4 mg perindopril or placebo daily for 15 weeks. The primary outcome was the between-group difference in force-plate measured anteroposterior (AP) sway at 15 weeks. Secondary outcomes included other measures of postural sway, limits of stability during maximal forward, right and left leaning, blood pressure, muscle strength, 6-min walk distance and falls. The primary outcome was assessed using two-way ANOVA, adjusted for baseline factors. we randomised 80 participants. Mean age was 78.0 (SD 7.4) years; 60 (75%) were female. About 77/80 (96%) completed the trial. At 15 weeks there were no significant between-group differences in AP sway with eyes open (mean difference 0 mm, 95% CI -8 to 7 mm, P = 0.91) or eyes closed (mean difference 2 mm, 95% CI -7 to 12 mm, P = 0.59); no differences in other measures of postural stability, muscle strength or function. About 16/40 (42%) of patients in each group had orthostatic hypotension at follow-up. The median number (IQR) of falls was 1 (0,4) in the perindopril versus 1 (0,2) in the placebo group (P = 0.24). perindopril did not improve postural sway in older people at risk of falls. ISRCTN58995463. © The Author 2017. Published by Oxford University Press on behalf of the British Geriatrics Society.

Detecting altered postural control after cerebral concussion in athletes with normal postural stability

OpenAIRE

Cavanaugh, J; Guskiewicz, K; Giuliani, C; Marshall, S; Mercer, V; Stergiou, N

2005-01-01

Objective: To determine if approximate entropy (ApEn), a regularity statistic from non-linear dynamics, could detect changes in postural control during quiet standing in athletes with normal postural stability after cerebral concussion.

The effects of anxiety and external attentional focus on postural control in patients with Parkinson's disease

Science.gov (United States)

Jazaeri, Seyede Zohreh; Azad, Akram; Mehdizadeh, Hajar; Habibi, Seyed Amirhassan; Mandehgary Najafabadi, Mahbubeh; Saberi, Zakieh Sadat; Rahimzadegan, Hawre; Moradi, Saeed; Behzadipour, Saeed; Parnianpour, Mohamad; Khalaf, Kinda

2018-01-01

Background Although anxiety is a common non-motor outcome of Parkinson's disease (PD) affecting 40% of patients, little attention has been paid so far to its effects on balance impairment and postural control. Improvement of postural control through focusing on the environment (i.e. external focus) has been reported, but the role of anxiety, as a confounding variable, remains unclear. Objectives This study aimed to investigate the influence of anxiety and attentional focus instruction on the standing postural control of PD patients. Methods Thirty-four patients with PD (17 with high anxiety (HA-PD) and 17 with low anxiety (LA-PD)), as well as 17 gender- and age-matched healthy control subjects (HC) participated in the study. Postural control was evaluated using a combination of two levels of postural difficulty (standing on a rigid force plate surface with open eyes (RO) and standing on a foam surface with open eyes (FO)), as well as three attentional focus instructions (internal, external and no focus). Results Only the HA-PD group demonstrated significant postural control impairment as compared to the control, as indicated by significantly greater postural sway measures. Moreover, external focus significantly reduced postural sway in all participants especially during the FO condition. Conclusion The results of the current study provide evidence that anxiety influences balance control and postural stability in patients with PD, particularly those with high levels of anxiety. The results also confirmed that external focus is a potential strategy that significantly improves the postural control of these patients. Further investigation of clinical applicability is warranted towards developing effective therapeutic and rehabilitative treatment plans. PMID:29390029

Is there a relationship between pain intensity and postural sway in patients with non-specific low back pain?

Science.gov (United States)

Ruhe, Alexander; Fejer, René; Walker, Bruce

2011-07-15

Increased center of pressure excursions are well documented in patients suffering from non-specific low back pain, whereby the altered postural sway includes both higher mean sway velocities and larger sway area. No investigation has been conducted to evaluate a relationship between pain intensity and postural sway in adults (aged 50 or less) with non-specific low back pain. Seventy-seven patients with non-specific low back pain and a matching number of healthy controls were enrolled. Center of pressure parameters were measured by three static bipedal standing tasks of 90 sec duration with eyes closed in narrow stance on a firm surface. The perceived pain intensity was assessed by a numeric rating scale (NRS-11), an equal number of patients (n = 11) was enrolled per pain score. Generally, our results confirmed increased postural instability in pain sufferers compared to healthy controls. In addition, regression analysis revealed a significant and linear increase in postural sway with higher pain ratings for all included COP parameters. Statistically significant changes in mean sway velocity in antero-posterior and medio-lateral direction and sway area were reached with an incremental change in NRS scores of two to three points. COP mean velocity and sway area are closely related to self-reported pain scores. This relationship may be of clinical use as an objective monitoring tool for patients under treatment or rehabilitation.

The association between head and cervical posture and temporomandibular disorders: a systematic review.

Science.gov (United States)

Olivo, Susan Armijo; Bravo, Jaime; Magee, David J; Thie, Norman M R; Major, Paul W; Flores-Mir, Carlos

2006-01-01

To carry out a systematic review to assess the evidence concerning the association between head and cervical posture and temporomandibular disorders (TMD). A search of Medline, Pubmed, Embase, Web of Science, Lilacs, and Cochrane Library databases was conducted in all languages with the help of a health sciences librarian. Key words used in the search were posture, head posture, cervical spine or neck, vertebrae, cervical lordosis, craniomandibular disorders or temporomandibular disorders, temporomandibular disorders, and orofacial pain or facial pain. Abstracts which appeared to fulfill the initial selection criteria were selected by consensus. The original articles were retrieved and evaluated to ensure they met the inclusion criteria. A methodological checklist was used to evaluate the quality of the selected articles and their references were hand-searched for possible missing articles. Twelve studies met all inclusion criteria and were analyzed in detail for their methodology and information quality. Nine articles that analyzed the association between head posture and TMD included patients with mixed TMD diagnosis; 1 article differentiated among muscular, articular, and mixed symptomatology; and 3 articles analyzed information from patients with only articular problems. Finally, 2 studies evaluated the association between head posture and TMD in patients with muscular TMD. Several methodological defects were noted in the 12 studies. Since most of the studies included in this systematic review were of poor methodological quality, the findings of the studies should be interpreted with caution. The association between intra-articular and muscular TMD and head and cervical posture is still unclear, and better controlled studies with comprehensive TMD diagnoses, greater sample sizes, and objective posture evaluation are necessary.

Anatomy and histochemistry of hindlimb flight posture in birds. I. The extended hindlimb posture of shorebirds.

Science.gov (United States)

McFarland, Joshua C; Meyers, Ron A

2008-08-01

Birds utilize one of two hindlimb postures during flight: an extended posture (with the hip and knee joints flexed, while the ankle joint is extended caudally) or a flexed posture (with the hip, knee, and ankle joints flexed beneath the body). American Avocets (Recurvirostra americana) and Black-necked Stilts (Himantopus mexicanus) extend their legs caudally during flight and support them for extended periods. Slow tonic and slow twitch muscle fibers are typically found in muscles functioning in postural support due to the fatigue resistance of these fibers. We hypothesized that a set of small muscles composed of high percentages of slow fibers and thus dedicated to postural support would function in securing the legs in the extended posture during flight. This study examined the anatomy and histochemical profile of eleven hindlimb muscles to gain insight into their functional roles during flight. Contrary to our hypothesis, all muscles possessed both fast twitch and slow twitch or slow tonic fibers. We believe this finding is due to the versatility of dynamic and postural functions the leg muscles must facilitate, including standing, walking, running, swimming, and hindlimb support during flight. Whether birds use an extended or flexed hindlimb flight posture may be related to the aerodynamic effect of leg position or may reflect evolutionary history. (c) 2008 Wiley-Liss, Inc.

Computer use in school: its effect on posture and discomfort in schoolchildren.

LENUS (Irish Health Repository)

Kelly, Grace

2009-01-01

The aim of the study was to investigate the posture and musculoskeletal discomfort of secondary school students while working at computers in school. Students (n = 40) were observed while working at a computer during their designated computer class. The Rapid Upper Limb Assessment Tool (RULA) was used to assess posture. A Body Discomfort Chart (BDC) and Visual Analogue Scale (VAS) were used to record the area(s) and intensity of musculoskeletal discomfort, if any, experienced by the students at the beginning and end of the computer class. None of the students\\' posture was in the acceptable range (Action Level 1) according to RULA. The majority (65%) were in Action Level 2, 30% were in Action Level 3, and 5% were in Action Level 4. There was a statistically significant increase in reported discomfort from the beginning to the end of the computer class. Longer class length (80 minutes) did not result in greater reporting of discomfort than shorter class length (40 minutes).

The dentist's operating posture - ergonomic aspects.

Science.gov (United States)

Pîrvu, C; Pătraşcu, I; Pîrvu, D; Ionescu, C

2014-06-15

The practice of dentistry involves laborious high finesse dental preparations, precision and control in executions that require a particular attention, concentration and patience of the dentist and finally the dentist's physical and mental resistance. The optimal therapeutic approach and the success of practice involve special working conditions for the dentist and his team in an ergonomic environment. The meaning of the posture in ergonomics is the manner in which different parts of the body are located and thus the reports are established between them in order to allow a special task execution. This article discusses the posture adopted by dentists when they work, beginning with the balanced posture and going to different variants of posture. The ideal posture of a dentist gives him, on the one hand the optimal working conditions (access, visibility and control in the mouth) and on the other hand, physical and psychological comfort throughout the execution of the clinical acts. Although the theme of dentist posture is treated with great care and often presented in the undergraduate courses and the continuing education courses on ergonomics in dentistry, many dentists do not know the subject well enough nor the theoretical issues and therefore nor the practical applicability. The risk and perspective of the musculoskeletal disorders related to unbalanced postures should determine the dentists take postural corrective actions and compensation measures in order to limit the negative effects of working in a bad posture.

Relationship between Muscle Function, Muscle Typology and Postural Performance According to Different Postural Conditions in Young and Older Adults.

Science.gov (United States)

Paillard, Thierry

2017-01-01

Although motor output of the postural function clearly influences postural performance in young and older subjects, no relationship has been formally established between them. However, the relationship between lower-extremity muscle strength/power and postural performance is often pointed out, especially in older subjects. In fact, the influence of motor output may vary according to the postural condition considered (e.g., static, dynamic, challenging, disturbing). In static postural condition, there may be a relationship between lower-extremity muscle strength and postural performance when the value of muscle strength is below a certain threshold in older subjects. Above this threshold of muscle strength, this relationship may disappear. In dynamic postural condition, lower-extremity muscle power could facilitate compensatory postural actions, limiting induced body imbalance likely to generate falls in older subjects. In young subjects, there could be a relationship between very early rapid torque of the leg extensor muscles and postural performance. In the case of postural reaction to (external) perturbations, a high percentage of type II muscle fibers could be associated with the ability to react quickly to postural perturbations in young subjects, while it may enable a reduction in the risk of falls in older subjects. In practice, in older subjects, muscle strength and/or power training contributes to reducing the risk of falls, as well as slowing down the involution of muscle typology regarding type II muscle fibers.

Overview of the management of postural tachycardia syndrome in pregnant patients.

Science.gov (United States)

Ruzieh, Mohammed; Grubb, Blair P

2018-02-16

Postural tachycardia syndrome (POTS) is a chronic condition characterized by symptoms of orthostatic intolerance. Pregnancy can cause different physiological changes in cardiovascular parameters, that could have greater impact on POTS patients. In this review, we discuss the management of POTS in the pregnant and obstetric settings. Copyright © 2018 Elsevier B.V. All rights reserved.

Hippotherapy on postural balance in the sitting position of children with cerebral palsy - Longitudinal study.

Science.gov (United States)

Moraes, Andréa Gomes; Copetti, Fernando; Ângelo, Vera Regina; Chiavoloni, Luana; de David, Ana Cristina

2018-06-11

To verify the effects of 12, 24, 36 hippotherapy sessions over time on postural balance while sitting in children with cerebral palsy as well the effects of treatment after one interruption period of 45 days. Hippotherapy program with a twice-weekly treatment with a total of 13 children aged 5-10 years old. Measurements of postural balance during sitting were performed using the AMTI AccuSway Plus platform. There was a statistically significant reduction in mediolateral and anteroposterior sway after the first 12 hippotherapy sessions, and further significant sway reduction occurred as the treatment progressed. Changes in the center of pressure displacement velocity variable began to occur after 24 sessions. Seated postural balance improved in children with cerebral palsy, as evidenced by lower COP displacement, particularly after a greater number of sessions. After the last evaluations, when completing 36 sessions of hippotherapy, it was verified that the improvements to the postural balance continued to occur. Therefore, further studies with a longer treatment period may help to clarify if, at some point, there is stabilization in the improvement of postural balance. Furthermore, it is important to analyze the impact of hippotherapy on functional activities over time.

Postural risk assessment of mechanised firewood processing.

Science.gov (United States)

Spinelli, Raffaele; Aminti, Giovanni; De Francesco, Fabio

2017-03-01

The study assessed the postural risk of mechanised firewood processing with eight machines, representing the main technology solutions available on the market. Assessment was conducted with the Ovako Working posture Analysis System (OWAS) on 1000 still frames randomly extracted from videotaped work samples. The postural risk associated with firewood processing was variable and associated with technology type. Simple, manually operated new machines incurred a higher postural risk compared with semi- or fully automatic machines. In contrast, new semi-automatic and automatic machines were generally free from postural risk. In all cases, attention should be paid to postural risk that may occur during blockage resolution. The study did not cover the postural risk of firewood processing sites as a whole. The study provided useful information for selecting firewood processing machinery and for improving firewood machinery design, as part of a more articulate strategy aimed at enhancing the safety of firewood processing work sites. Practitioner Summary: The postural risk associated with mechanised firewood processing (eg cutting and splitting) depends on the type of equipment. Postural risk is highest (OWAS Action Category 2) with new in-line machines, designed for operation by a single worker. Fully automatic machines present minimum postural risk, except during blockage resolution.

Physiological Mechanisms Mediating the Coupling between Heart Period and Arterial Pressure in Response to Postural Changes in Humans

OpenAIRE

Silvani, Alessandro; Calandra-Buonaura, Giovanna; Johnson, Blair D.; van Helmond, Noud; Barletta, Giorgio; Cecere, Anna G.; Joyner, Michael J.; Cortelli, Pietro

2017-01-01

The upright posture strengthens the coupling between heart period (HP) and systolic arterial pressure (SAP) consistently with a greater contribution of the arterial baroreflex to cardiac control, while paradoxically decreasing cardiac baroreflex sensitivity (cBRS). To investigate the physiological mechanisms that mediate the coupling between HP and SAP in response to different postures, we analyzed the cross-correlation functions between low-frequency HP and SAP fluctuations and estimated cBR...

Postural control is altered in patients with ankylosing spondylitis.

Science.gov (United States)

Vergara, Martin E; O'Shea, Finbar D; Inman, Robert D; Gage, William H

2012-05-01

Ankylosing spondylitis is a chronic inflammatory disorder that can lead to increased axial and peripheral joint stiffness, impairing joint mobility. Impaired axial mobility due to vertebral ankylosis may result in changes in standing postural control. Little research has addressed changes in standing postural control in the ankylosing spondylitis population, nor how these issues might affect clinical understanding and treatment. Sixteen ankylosing spondylitis patients, and 17 healthy controls participated. Each individual completed two 120-second quiet standing trials with eyes open and eyes closed, while standing upon two force platforms. Net center of pressure displacement and mean power frequency in the frontal and sagittal planes were calculated. A Spearman's rank correlation analysis was performed between net center of pressure measures and several clinical measures of disease activity. Frontal plane net center of pressure displacement and frequency content, and sagittal plane net center of pressure displacement were significantly greater within the ankylosing spondylitis patient group. Ankylosing spondylitis patients demonstrated a significant increase in frontal plane net center of pressure displacement in the eyes-closed condition. Net center of pressure displacement and frequency were significantly correlated to the Bath Ankylosing Spondylitis Functional Index, and individual components of the Bath Ankylosing Spondylitis Metrology Index. Quiet standing postural control was altered particularly so in the frontal plane in patients with ankylosing spondylitis, which may be associated with increased fall risk. Posturographic measures of postural control may serve as valuable clinical tools for the monitoring of disease progression and disease status in ankylosing spondylitis. Copyright © 2011 Elsevier Ltd. All rights reserved.

Predictors of vertigo in patients with untreated vestibular schwannoma.

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Andersen, Jan Fredrik; Nilsen, Kathrin Skorpa; Vassbotn, Flemming Slinning; Møller, Per; Myrseth, Erling; Lund-Johansen, Morten; Goplen, Frederik Kragerud

2015-04-01

Previous studies have shown that vertigo is the most powerful negative predictor of quality of life in patients with vestibular schwannomas, but the variability in vertigo symptom severity is still poorly understood. We wanted to find out whether vertigo could be related to objective parameters such as tumor size, location, vestibular nerve function, hearing, and postural stability in patients with untreated vestibular schwannomas. Baseline data from prospective cohort study. Tertiary referral center. Four hundred thirty-four consecutive patients with unilateral VS diagnosed on MRI. Mean age 56 years (range 16-84 yr). Fifty-three percent women. Diagnostic, with a medical history, otolaryngological examination, pure-tone and speech audiometry, MRI, posturography, and videonystagmography with bithermal caloric tests. Dizziness measured on a 100-mm visual analog scale (VAS). Secondary outcome measures were canal paresis and postural imbalance (static and dynamic posturography). Three hundred three patients (70%) completed the VAS. Severe dizziness, defined as VAS 75 or greater, was reported by 9% of the patients. Larger tumors were associated with higher risk of postural instability and canal paresis. Moderate to severe dizziness was associated with postural imbalance and canal paresis, and possibly with small to medium-sized tumors. Postural instability was related to tumor size and canal paresis when measured by dynamic, but not with static, posturography. A minority of VS patients experience severe vestibular symptoms related to canal paresis and postural instability. A curvilinear relationship is hypothesized between tumor size and dizziness.

Relationship between postural alignment in sitting by photogrammetry and seated postural control in post-stroke subjects.

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Iyengar, Y R; Vijayakumar, K; Abraham, J M; Misri, Z K; Suresh, B V; Unnikrishnan, B

2014-01-01

This study was executed to find out correlation between postural alignment in sitting measured through photogrammetry and postural control in sitting following stroke. A cross-sectional study with convenient sampling consisting of 45 subjects with acute and sub-acute stroke. Postural alignment in sitting was measured through photogrammetry and relevant angles were obtained through software MB Ruler (version 5.0). Seated postural control was measured through Function in Sitting Test (FIST). Correlation was obtained using Spearman's Rank Correlation co-efficient in SPSS software (version 17.0). Moderate positive correlation (r = 0.385; p < 0.01) was found between angle of lordosis and angle between acromion, lateral epicondyle and point between radius and ulna. Strong negative correlation (r = -0.435; p < 0.01) was found between cranio-vertebral angle and kyphosis. FIST showed moderate positive correlation (r = 0.3446; p < 0.05) with cranio-vertebral angle and strong positive correlation (r = 0.4336; p < 0.01) with Brunnstrom's stage of recovery in upper extremity. Degree of forward head posture in sitting correlates directly with seated postural control and inversely with degree of kyphosis in sitting post-stroke. Postural control in sitting post-stroke is directly related with Brunnstrom's stage of recovery in affected upper extremity in sitting.

Aging Worsens the Effects of Sleep Deprivation on Postural Control

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Robillard, Rébecca; Prince, François; Filipini, Daniel; Carrier, Julie

2011-01-01

Falls increase with age and cause significant injuries in the elderly. This study aimed to determine whether age modulates the interactions between sleep deprivation and postural control and to evaluate how attention influences these interactions in the elderly. Fifteen young (24±2.7 y.o.) and 15 older adults (64±3.2 y.o.) stood still on a force plate after a night of sleep and after total sleep deprivation. Center of pressure range and velocity were measured with eyes open and with eyes closed while participants performed an interference task, a control task, and no cognitive task. Sleep deprivation increased the antero-posterior range of center of pressure in both age groups and center of pressure speed in older participants only. In elderly participants, the destabilizing effects of sleep deprivation were more pronounced with eyes closed. The interference task did not alter postural control beyond the destabilization induced by sleep loss in older subjects. It was concluded that sleep loss has greater destabilizing effects on postural control in older than in younger participants, and may therefore increase the risk of falls in the elderly. PMID:22163330

Aging worsens the effects of sleep deprivation on postural control.

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Robillard, Rébecca; Prince, François; Filipini, Daniel; Carrier, Julie

2011-01-01

Falls increase with age and cause significant injuries in the elderly. This study aimed to determine whether age modulates the interactions between sleep deprivation and postural control and to evaluate how attention influences these interactions in the elderly. Fifteen young (24±2.7 y.o.) and 15 older adults (64±3.2 y.o.) stood still on a force plate after a night of sleep and after total sleep deprivation. Center of pressure range and velocity were measured with eyes open and with eyes closed while participants performed an interference task, a control task, and no cognitive task. Sleep deprivation increased the antero-posterior range of center of pressure in both age groups and center of pressure speed in older participants only. In elderly participants, the destabilizing effects of sleep deprivation were more pronounced with eyes closed. The interference task did not alter postural control beyond the destabilization induced by sleep loss in older subjects. It was concluded that sleep loss has greater destabilizing effects on postural control in older than in younger participants, and may therefore increase the risk of falls in the elderly.

Cardiovascular and Postural Control Interactions during Hypergravity: Effects on Cerebral Autoregulation in Males and Females

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Goswami, Nandu; Blaber, Andrew; Bareille, Marie-Pierre; Beck, Arnaud; Avan, Paul; Bruner, Michelle; Hinghofer-Szalkay, Helmut

2012-07-01

Orthostatic intolerance remains a problem upon return to Earth from the microgravity environment of spaceflight. A variety of conditions including hypovolemia, cerebral vasoconstriction, cerebral or peripheral vascular disease, or cardiac arrhythmias may result in syncope if the person remains upright. Current research indicates that there is a greater dependence on visual and somatosensory information at the beginning of space flight with a decreased otolith gain during prolonged space flight (Herault et al., 2002). The goal of the research is to further our understanding of the fundamental adaptive homeostatic mechanisms involved in gravity related changes in cardiovascular and postural function. Cardiovascular, cerebrovascular, and postural sensory motor control systems in male and female participants before, during, and after exposure to graded levels of hyper-G were investigated. Hypotheses: 1) Activation of skeletal muscle pump will be directly related to the degree of orthostatic stress. 2) Simultaneous measurement of heart rate, blood pressure and postural sway will predict cardio-postural stability. Blood pressure and heart rate (means and variability), postural sway, center of pressure (COP), baroreflex function, calf blood flow, middle cerebral artery blood flow, non-invasive intracranial pressure measurements, and two-breath CO2 were measured. Results from the study will be used to provide an integrated insight into mechanisms of cardio-postural control and cerebral autoregulation, which are important aspects of human health in flights to Moon, Mars and distant planets.

Body posture and pulmonary function in mouth and nose breathing children: cross-sectional study

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Jovana de Moura Milanesi

Full Text Available Abstract Introduction: Mouth breathing can lead to changes in body posture and pulmonary function. However, the consequences are still inconclusive and a number of studies are controversial. Objective: Evaluate and correlate spirometric parameters and postural measures in mouth breathing children, and compare them to nose breathers. Methods: two groups of 6 to 12 year-old children were evaluated: mouth breathers (MB, n = 55 and nose breathers (NB, n = 45. Spirometry and body posture analysis using photogrammetry (SAPo 0.68® v were carried out. The following spirometric measures were evaluated: peak expiratory flow (PEF, forced expiratory volume in 1 second (FEV1, forced vital capacity (FVC, FEV1/FVC ratio (% and forced expiratory flow between 25% and 75% of FVC (FEF 25-75%. Biophotogrammetric measures analyzed were: horizontal alignment of acromions (HAA and anterior superior iliac spine (HAASIS, Charpy angle, horizontal alignment of the head (HAH, cervical lordosis (CL, thoracic kyphosis (TK, lumbar lordosis (LL, cervical distance (CD and lumbar distance (LD. Results: There were no intergroup differences in spirometric and postural variables. Positive and moderate correlations were found between CL and CD measures with PEF, FEV1, FVC and FEF 25-75%, while weak correlations were observed between lumbar lordosis and PEF, FEV1 and FVC. Conclusion: The breathing mode had no influence on postural and respiratory measures. However, greater forward head posture, with smaller cervical lordosis, was related to higher lung volumes and flows in both groups.

On the functional integration between postural and supra-postural tasks on the basis of contextual cues and task constraint.

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de Lima, Andrea Cristina; de Azevedo Neto, Raymundo Machado; Teixeira, Luis Augusto

2010-10-01

In order to evaluate the effects of uncertainty about direction of mechanical perturbation and supra-postural task constraint on postural control, young adults had their upright stance perturbed while holding a tray in a horizontal position. Stance was perturbed by moving forward or backward a supporting platform, contrasting situations of certainty versus uncertainty of direction of displacement. Increased constraint on postural stability was imposed by a supra-postural task of equilibrating a cylinder on the tray. Performance was assessed through EMG of anterior leg muscles, angular displacement of the main joints involved in the postural reactions and displacement of the tray. Results showed that both certainty on the direction of perturbation and increased supra-postural task constraint led to decreased angular displacement of the knee and the hip. Furthermore, combination of certainty and high supra-postural task constraint produced shorter latency of muscular activation. Such postural responses were paralleled by decreased displacement of the tray. These results suggest a functional integration between the tasks, with central set priming reactive postural responses from contextual cues and increased stability demand. Copyright © 2010 Elsevier B.V. All rights reserved.

Human posture experiments under water: ways of applying the findings to microgravity

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Dirlich, Thomas

differences between underwater and real microgravity environment were analyzed in greater detail: external forces (buoyancy and grav-ity), required fixation, postural changes by breathing and subject orientation to gravitational vector. Goal of this analysis was to understand the respective effects of each environmental influence on subjects posture observed. Each of the different influences was then quantified and the postural change induced by it calculated. These were then combined using a specially programmed multi-body-simulation tool, making it possible to recompute 3D posture data dy-namically to the environmental influences. The simulation is based on the volumetric 3D model of each subject, specific anthropometric data, such as body-fat or muscle ratio, combined with external forces such as gravity and buoyancy. The recomputed data can then be compared independent from the environmental influences. The recomputed 3D posture data can then be re-evaluated focussing again on possible inter-personal neutral posture archetypes in the subject group. Some examples of recomputed data and inter-personal findings will be given.

Neck pain and postural balance among workers with high postural demands - a cross-sectional study

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2011-01-01

Background Neck pain is related to impaired postural balance among patients and is highly prevalent among workers with high postural demands, for example, cleaners. We therefore hypothesised, that cleaners with neck pain suffer from postural dysfunction. This cross-sectional study tested if cleaners with neck pain have an impaired postural balance compared with cleaners without neck pain. Methods Postural balance of 194 cleaners with (n = 85) and without (N = 109) neck pain was studied using three different tests. Success or failure to maintain the standing position for 30 s in unilateral stance was recorded. Participants were asked to stand on a force platform for 30 s in the Romberg position with eyes open and closed. The centre of pressure of the sway was calculated, and separated into a slow (rambling) and fast (trembling) component. Subsequently, the 95% confidence ellipse area (CEA) was calculated. Furthermore a perturbation test was performed. Results More cleaners with neck pain (81%) failed the unilateral stance compared with cleaners without neck pain (61%) (p neck pain in comparison with cleaners without neck pain in the Romberg position with eyes closed, but not with eyes open. Conclusions Postural balance is impaired among cleaners with neck pain and the current study suggests a particular role of the slow component of postural sway. Furthermore, the unilateral stance test is a simple test to illustrate functional impairment among cleaners with concurrent neck and low back pain. Trial registration ISRCTN96241850 PMID:21806796

Fatiguing exercise intensity influences the relationship between parameters reflecting neuromuscular function and postural control variables.

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Sébastien Boyas

Full Text Available The purpose of this study was to investigate the influence of fatiguing exercise intensity on the nature and extent of fatigue-induced changes in neuromuscular function and postural stability in quiet standing. We also explored the contribution of selected neuromuscular mechanisms involved in force production to postural stability impairment observed following fatigue using an approach based on multivariate regressions. Eighteen young subjects performed 30-s postural trials on one leg with their eyes closed. Postural trials were performed before and after fatiguing exercises of different intensities: 25, 50 and 75% of maximal isometric plantarflexor torque. Fatiguing exercises consisted of sustaining a plantarflexor isometric contraction at the target intensity until task failure. Maximal isometric plantarflexor torque, electromyographic activity of plantarflexor and dorsiflexor muscles, activation level (twitch interpolation technique and twitch contractile properties of plantarflexors were used to characterize neuromuscular function. The 25% exercise was associated with greater central fatigue whereas the 50 and 75% exercises involved mostly peripheral fatigue. However, all fatiguing exercises induced similar alterations in postural stability, which was unexpected considering previous literature. Stepwise multiple regression analyses showed that fatigue-related changes in selected parameters related to neuromuscular function could explain more than half (0.51≤R(2≤0.82 of the changes in postural variables for the 25% exercise. On the other hand, regression models were less predictive (0.17≤R(2≤0.73 for the 50 and 75% exercises. This study suggests that fatiguing exercise intensity does not influence the extent of postural stability impairment, but does influence the type of fatigue induced and the neuromuscular function predictors explaining changes in postural variables.

Automated Assessment of Postural Stability (AAPS)

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2016-10-01

performed a battery of standard clinical tests of dynamic posture, whereas the fourth subject performed the stereotyped postures (e.g. movements restricted...Processing & Control [2] Napoli A, Ward C, Glass S, Tucker C, Obeid I (2016) “Automated Assessment of Postural Stability System,” IEEE Engineering in

Postural Control in Children with Autism.

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Kohen-Raz, Reuven; And Others

1992-01-01

Postural control was evaluated in 91 autistic, 166 normal, and 18 mentally retarded children using a computerized posturographic procedure. In comparison to normal children, the autistic subjects were less likely to exhibit age-related changes in postural performance, and postures were more variable and less stable. (Author/JDD)

Effect of six weeks of dura disc and mini-trampoline balance training on postural sway in athletes with functional ankle instability.

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Kidgell, Dawson J; Horvath, Deanna M; Jackson, Brendan M; Seymour, Philip J

2007-05-01

Lateral ankle sprain (LAS) is one of the most common injuries incurred during sporting activities, and effective rehabilitation programs for this condition are challenging to develop. The purpose of this research was to compare the effect of 6 weeks of balance training on either a mini-trampoline or a dura disc on postural sway and to determine if the mini-trampoline or the dura disc is more effective in improving postural sway. Twenty subjects (11 men, 9 women) with a mean age of 25.4 +/- 4.2 years were randomly allocated into a control group, a dura disc training (DT) group, or a mini-trampoline (MT) group. Subjects completed 6 weeks of balance training. Postural sway was measured by subjects performing a single limb stance on a force plate. The disbursement of the center of pressure was obtained from the force plate in the medial-lateral and the anterior-posterior sway path and was subsequently used for pretest and posttest analysis. After the 6-week training intervention, there was a significant (p 0.05) difference detected for improvements between the MT and DT groups. These results indicate that not only is the mini-trampoline an effective tool for improving balance after LAS, but it is equally as effective as the dura disc.

Sectoral Diversification as Insurance against Economic Instability

OpenAIRE

Jan Kluge

2015-01-01

This paper examines the extent to which sectoral diversification can act as an insurance mechanism against fluctuations in regional gross value added growth rates. I apply portfolio theory to the growth-instability properties of German districts. Furthermore, I define a comprehensive diversification measure and use Stochastic Frontier Analysis in order to estimate whether diversification allows regions to achieve more efficient growth-instability combinations, i.e., greater stability at given...

Carrying shopping bags does not alter static postural stability and gait parameters in healthy older females.

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Bampouras, Theodoros M; Dewhurst, Susan

2016-05-01

Food shopping is an important aspect of maintaining independence and social interaction in older age. Carriage of shopping bags alters the body's weight distribution which, depending on load distribution, could potentially increase instability during standing and walking. The study examined the effect of carrying UK style shopping bags on static postural stability and gait in healthy older and young females. Nine older (71.0±6.0 years) and 10 young (26.7±5.2 years) females were assessed in five conditions carrying no bags, one 1.5kg bag in each hand, one 3kg bag in each hand, one 1.5kg bag in preferred hand, one 3kg bag in preferred hand. Antero-posterior and medio-lateral displacement, and 95% ellipse area from a 30s quiet standing were used for postural stability assessment. Stride length and its coefficient of variation, total double support time, step asymmetry and gait stability ratio were calculated from 1min treadmill walking at self-selected speed for gait assessment. Carrying shopping bags did not negatively affect postural stability or gait variables, in either group. Further, in older individuals, a decrease in sway velocity was found when holding bags during the postural stability assessment (pbags, irrespective of the load distribution, may have a stabilising effect during quiet standing. These results should help to alleviate concerns regarding safety of carrying shopping bags and help encourage shopping, both as a social and as a physical activity. Copyright © 2016 Elsevier B.V. All rights reserved.

Postural adaptations to long-term training in Prader-Willi patients

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2011-01-01

Background Improving balance and reducing risk of falls is a relevant issue in Prader-Willi Syndrome (PWS). The present study aims to quantify the effect of a mixed training program on balance in patients with PWS. Methods Eleven adult PWS patients (mean age: 33.8 ± 4.3 years; mean BMI: 43.3 ± 5.9 Kg/m2) attended a 2-week training program including balance exercises during their hospital stay. At discharge, Group 1 (6 patients) continued the same exercises at home for 6 months, while Group 2 (5 patients) quitted the program. In both groups, a low-calorie, well-balanced diet of 1.200 kcal/day was advised. They were assessed at admission (PRE), after 2 weeks (POST1) and at 6-month (POST2). The assessment consisted of a clinical examination, video recording and 60-second postural evaluation on a force platform. Range of center of pressure (CoP) displacement in the antero-posterior direction (RANGEAP index) and the medio-lateral direction (RANGEML index) and its total trajectory length were computed. Results At POST1, no significant changes in all of the postural parameters were observed. At completion of the home program (POST2), the postural assessment did not reveal significant modifications. No changes in BMI were observed in PWS at POST2. Conclusions Our results showed that a long-term mixed, but predominantly home-based training on PWS individuals was not effective in improving balance capacity. Possible causes of the lack of effectiveness of our intervention include lack of training specificity, an inadequate dose of exercise, an underestimation of the neural and sensory component in planning rehabilitation exercise and failed body weight reduction during the training. Also, the physiology of balance instability in these patients may possibly compose a complex puzzle not affected by our exercise training, mainly targeting muscle weakness. PMID:21575153

The Effect of Balance Training on Postural Control in Patients with Parkinson's Disease Using a Virtual Rehabilitation System.

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Albiol-Pérez, Sergio; Gil-Gómez, José-Antonio; Muñoz-Tomás, María-Teresa; Gil-Gómez, Hermenegildo; Vial-Escolano, Raquel; Lozano-Quilis, José-Antonio

2017-03-23

Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by motor clinical alterations among others. Postural problems have serious consequences for patients, not only limiting their daily life but also increasing some risks, like the risk of fall. Inadequate postural control and postural instability is a major problem in PD patients. A Virtual Motor Rehabilitation System (VMR) has been tested in patients with PD in the intervention period. Our purpose was to analyze the evolution of the spatial postural control during the intervention period, to see if there are any changes caused precisely by this intervention. Ten people with PD carried out 15 virtual rehabilitation sessions. We tested a groundbreaking system based on Virtual Motor Rehabilitation in two periods of time (baseline evaluation and final evaluation). In the training sessions, the participants performed a customizable treatment using a low-cost system, the Active Balance Rehabilitation system (ABAR). We stored the pressure performed by the participants every five hundredths of a second, and we analyzed the patients' pressure when they maintained their body on the left, on the right, and in the center in sitting position. Our system was able to measure postural control in every patient in each of the virtual rehabilitation sessions. There are no significant differences in the performance of postural control in any of the positions evaluated throughout the sessions. Moreover, the results show a trend to an improvement in all positions. This improvement is especially remarkable in the left/right positions, which are the most important positions in order to avoid problems such as the risk of fall. With regard to the suitability of the ABAR system, we have found outstanding results in enjoyment, success, clarity, and helpfulness. Although PD is a progressive neurodegenerative disorder, the results demonstrate that patients with PD maintain or even improve their postural control

Beyond deficit or compensation: new insights on postural control after long-term total visual loss.

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Russo, Maitê M; Lemos, Thiago; Imbiriba, Luís A; Ribeiro, Nathalia L; Vargas, Claudia D

2017-02-01

Loss of vision is well known to affect postural control in blind subjects. This effect has classically been framed in terms of deficit or compensation depending on whether body sway increases or decreases in comparison with that of sighted subjects with the eyes open. However, studies have shown that postural responses can be modulated by the context and that changes in postural sway may not necessarily mean a worsened or improved postural control. The goal of our study was to test whether balance is affected by the context in blind subjects. Additional to the quantification of center of pressure (COP) displacement, measurements of body motion (COG) and the correspondent net neuromuscular response (COP-COG) were evaluated in anterior-posterior and medial-lateral directions. Thirty-eight completely blind and thirty-two sighted subjects participated of this study. The volunteers were asked to stand barefoot on a force platform for 60 s in two different conditions: feet apart and feet together. Sighted participants performed the tests with both the eyes open and eyes closed. Results showed that the COP-COG displacements in the blind group were greater than those of the sighted group with eyes open in almost all conditions tested, but not in eyes closed condition. However, the COP and COG results confirmed that the postural responses were context dependent. Together these results suggest that total visual loss does not just lead to a balance deficit or compensation, but to a specific postural signature that might imply in enhancing COP, COG and/or COP-COG in specific postural conditions.

Adiposity and postural balance control: correlations between bioelectrical impedance and stabilometric signals in elderly Brazilian women

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Míriam Raquel Meira Mainenti

2011-01-01

Full Text Available OBJECTIVE: The purpose of this study was to investigate the correlation between body adiposity and postural control in elderly women. INTRODUCTION: Aging and obesity account for a significant portion of healthcare spending. Life expectancy is increasing worldwide, and Rio de Janeiro has the largest proportion of elderly residents of all Brazilian states. METHODS: A total of 45 women underwent bioelectrical impedance analysis, waist circumference measurements, weight and height measurements, and stabilometric tests in eight different stance conditions (opened and closed bases with both eyes opened and closed and right and left tandem and unilateral stances with eyes opened. During unilateral stances, the number of hand or foot contacts was counted. RESULTS: Weight, body mass index, waist circumference, fat percentage, and fat mass showed statistically significant (p,0.05 and positive correlations with the number of contacts made during unilateral stances. The subjects with greater fat mass showed significantly higher anterior-posterior standard deviation and range when their eyes were closed. The sway area was also greater for this group in opened base when their eyes were closed. DISCUSSION: The results relating body adiposity and postural control can be explained by the difficulty of maintaining a greater quantity of body fat mass within the limits of the individual support base, especially while assuming a unilateral stance. CONCLUSION: The subjects with a greater fat mass exhibited poor balance control, indicating that body adiposity level was associated with postural control in the elderly women examined in the present study.

Factors that influence soft tissue thickness over the greater trochanter: application to understanding hip fractures.

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Levine, Iris C; Minty, Lauren E; Laing, Andrew C

2015-03-01

Fall-related hip injuries are a concern for the growing population of older adults. Evidence suggests that soft tissue overlying the greater trochanter attenuates the forces transmitted to the proximal femur during an impact, reducing mechanical risk of hip fracture. However, there is limited information about the factors that influence trochanteric soft tissue thickness. The current study used ultrasonography and electromyography to determine whether trochanteric soft tissue thickness could be quantified reproducibly and whether it was influenced by: (1) gender; (2) hip postures associated with potential falling configurations in the sagittal plane (from 30° of extension to 60° of flexion, at 15° intervals), combined adduction-flexion, and combined adduction-extension; and (3) activation levels of the tensor fascia lata (TFL) and gluteus medius (GM) muscles. Our results demonstrated that soft tissue thickness can be measured reliably in nine hip postures and three muscle activation conditions (for all conditions, ICC >0.98). Mean (SD) thickness in quiet stance was 2.52 cm. Thickness was 27.0% lower for males than females during quiet stance. It was 16.4% greater at maximum flexion than quiet standing, 27.2% greater at maximum extension, and 12.5% greater during combined adduction-flexion. However, there was no significant difference between combined adduction-extension and quiet standing. Thickness was not affected by changes in muscle activity. Forces applied to the femoral neck during a lateral fall decrease as trochanteric soft tissue thickness increases; gender and postural configuration at impact could influence the loads applied to the proximal femur (and thus hip fracture risk) during falls on the hip. © 2014 Wiley Periodicals, Inc.

The Relationship Between Postural and Movement Stability.

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Feldman, Anatol G

2016-01-01

Postural stabilization is provided by stretch reflexes, intermuscular reflexes, and intrinsic muscle properties. Taken together, these posture-stabilizing mechanisms resist deflections from the posture at which balance of muscle and external forces is maintained. Empirical findings suggest that for each muscle, these mechanisms become functional at a specific, spatial threshold-the muscle length or respective joint angle at which motor units begin to be recruited. Empirical data suggest that spinal and supraspinal centers can shift the spatial thresholds for a group of muscles that stabilized the initial posture. As a consequence, the same stabilizing mechanisms, instead of resisting motion from the initial posture, drive the body to another stable posture. In other words by shifting spatial thresholds, the nervous system converts movement resisting to movement-producing mechanisms. It is illustrated that, contrary to conventional view, this control strategy allows the system to transfer body balance to produce locomotion and other actions without loosing stability at any point of them. It also helps orient posture and movement with the direction of gravity. It is concluded that postural and movement stability is provided by a common mechanism.

Is there a relationship between pain intensity and postural sway in patients with non-specific low back pain?

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Fejer René

2011-07-01

Full Text Available Abstract Background Increased center of pressure excursions are well documented in patients suffering from non-specific low back pain, whereby the altered postural sway includes both higher mean sway velocities and larger sway area. No investigation has been conducted to evaluate a relationship between pain intensity and postural sway in adults (aged 50 or less with non-specific low back pain. Methods Seventy-seven patients with non-specific low back pain and a matching number of healthy controls were enrolled. Center of pressure parameters were measured by three static bipedal standing tasks of 90 sec duration with eyes closed in narrow stance on a firm surface. The perceived pain intensity was assessed by a numeric rating scale (NRS-11, an equal number of patients (n = 11 was enrolled per pain score. Results Generally, our results confirmed increased postural instability in pain sufferers compared to healthy controls. In addition, regression analysis revealed a significant and linear increase in postural sway with higher pain ratings for all included COP parameters. Statistically significant changes in mean sway velocity in antero-posterior and medio-lateral direction and sway area were reached with an incremental change in NRS scores of two to three points. Conclusions COP mean velocity and sway area are closely related to self-reported pain scores. This relationship may be of clinical use as an objective monitoring tool for patients under treatment or rehabilitation.

Cardiovascular function in pregnancy: effects of posture.

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Del Bene, R; Barletta, G; Mello, G; Lazzeri, C; Mecacci, F; Parretti, E; Martini, E; Vecchiarino, S; Franchi, F; La Villa, G

2001-04-01

To evaluate the cardiovascular response to active postural changes in pregnancy. Prospective study. Outpatient Clinic, Fetal Maternity Unit. Sixteen healthy women referred prior to pregnancy. Heart rate, arterial pressure, echocardiographic end-diastolic and end-systolic left ventricular volumes (Teichholz' s formula) were measured in the three months before pregnancy, at the end of the first and second trimester, at mid third trimester, and six months after delivery in the supine and standing position, in thirteen women (mean age 33, range 25-38 years). Cardiac output (supine position) significantly increased (28%): it reached its maximum at the second trimester, remained steadily elevated in the mid third trimester, and returned to baseline after delivery. Cardiac output increased during pregnancy also in the active orthostatic position, the percentage increase being greater (70%) since the standing pre-conception value was lower. The postural stress induced similar changes in heart rate, arterial pressure and left ventricular ejection fraction before, during and after pregnancy. However, the reduction in cardiac output associated with early standing attenuated significantly at the second trimester and it was absent at mid third trimester (F = 3.13, P = 0.021). This was due to the interplay between the significantly lesser increase in systemic vascular resistance, occurring since the first trimester, and the significantly lesser decrease in left ventricular end-diastolic volume which was observed in the mid third trimester. These data indicate that the elevated cardiac output is adequately maintained in pregnancy during the postural challenge, due to optimisation of the responses of preload and afterload.

Visual Vection does not Perturb Squatting Posture

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Dietrich Gilles

2011-12-01

Full Text Available Vision contributes fundamentally to the control of the standing posture. The illusion of self motion falsely perceived (vection increases postural sway while standing. In this paper we examine the effect of vection on both standing and deep squatting with the hypothesis that the squatting posture should not be disturbed by the conflict of sensory information due to vection. The results show that standing posture only was affected by the visual stimuli. The widespread use of squatting for work as well as rest could be due in part to this lack of effect of sensory perturbation on postural stability.

Change of Safe Needling Depth at Acupoint GB21 according to Posture and Breathing

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Hongmin Chu

2018-01-01

Full Text Available Acupoint GB21 (Jianjing is used for treating back and shoulder pain but is associated with a risk of pneumothorax. We aimed to determine the SND (safe needling depth at GB21 according to posture and breathing in real time. Ultrasonographic images of GB21 during normal breathing, inspiration, and expiration in a SP (sitting position were acquired for 52 healthy volunteers. Images were also acquired during normal respiration in the PP (prone position with arms raised and lowered. The average SND was greater for men than for women (p<0.05. Analysis of variance revealed that the SND was greater for the PP than for the SP (p=0.01 and p<0.05, resp.. Although the SND tended to change according to posture, the average depth tended to deviate widely in some subjects. During breathing, the differences between inspiration and expiration were less than 1 mm in most subjects, but some showed differences more than 4.5 mm. The SND at GB21 was greater in overweight subjects and significantly greater in the PP and during maximal expiration. However, intragroup differences were greater than the intergroup differences. Therefore, it is dangerous to simply apply needling depth on a gender or BMI basis. The practitioner would adjust the SND by examining the individual anatomical structures.

Effects of affective picture viewing on postural control

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Beek Peter J

2007-10-01

Full Text Available Abstract Background Emotion theory holds that unpleasant events prime withdrawal actions, whereas pleasant events prime approach actions. Recent studies have suggested that passive viewing of emotion eliciting images results in postural adjustments, which become manifest as changes in body center of pressure (COP trajectories. From those studies it appears that posture is modulated most when viewing pictures with negative valence. The present experiment was conducted to test the hypothesis that pictures with negative valence have a greater impact on postural control than neutral or positive ones. Thirty-four healthy subjects passively viewed a series of emotion eliciting images, while standing either in a bipedal or unipedal stance on a force plate. The images were adopted from the International Affective Picture System (IAPS. We analysed mean and variability of the COP and the length of the associated sway path as a function of emotion. Results The mean position of the COP was unaffected by emotion, but unipedal stance resulted in overall greater body sway than bipedal stance. We found a modest effect of emotion on COP: viewing pictures of mutilation resulted in a smaller sway path, but only in unipedal stance. We obtained valence and arousal ratings of the images with an independent sample of viewers. These subjects rated the unpleasant images as significantly less pleasant than neutral images, and the pleasant images as significantly more pleasant than neutral images. However, the subjects rated the images as overall less pleasant and less arousing than viewers in a closely comparable American study, pointing to unknown differences in viewer characteristics. Conclusion Overall, viewing emotion eliciting images had little effect on body sway. Our finding of a reduction in sway path length when viewing pictures of mutilation was indicative of a freezing strategy, i.e. fear bradycardia. The results are consistent with current knowledge about the

Postural Stability of Patients with Schizophrenia during Challenging Sensory Conditions: Implication of Sensory Integration for Postural Control.

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Teng, Ya-Ling; Chen, Chiung-Ling; Lou, Shu-Zon; Wang, Wei-Tsan; Wu, Jui-Yen; Ma, Hui-Ing; Chen, Vincent Chin-Hung

2016-01-01

Postural dysfunctions are prevalent in patients with schizophrenia and affect their daily life and ability to work. In addition, sensory functions and sensory integration that are crucial for postural control are also compromised. This study intended to examine how patients with schizophrenia coordinate multiple sensory systems to maintain postural stability in dynamic sensory conditions. Twenty-nine patients with schizophrenia and 32 control subjects were recruited. Postural stability of the participants was examined in six sensory conditions of different level of congruency of multiple sensory information, which was based on combinations of correct, removed, or conflicting sensory inputs from visual, somatosensory, and vestibular systems. The excursion of the center of pressure was measured by posturography. Equilibrium scores were derived to indicate the range of anterior-posterior (AP) postural sway, and sensory ratios were calculated to explore ability to use sensory information to maintain balance. The overall AP postural sway was significantly larger for patients with schizophrenia compared to the controls [patients (69.62±8.99); controls (76.53±7.47); t1,59 = -3.28, pmaintain balance compared to the controls.

Reversibility of pulmonary function after inhaling salbutamol in different doses and body postures in asthmatic children.

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Visser, R; Kelderman, S; de Jongh, F H C; van der Palen, J; Thio, B J

2015-10-01

Pulmonary medication is often delivered in the form of medical aerosols designed for inhalation. Recently, breath actuated inhalers (BAI's) gained popularity as they can be used without spacers. A major drawback of BAI's is the impaction in the upper airway. Stretching the upper airway by a forward leaning body posture with the neck extended ("sniffing position") during inhalation may reduce upper airway impaction and improve pulmonary deposition. Aim of this study was to investigate the reversibility of lung function with different doses salbutamol inhaled with a BAI in the forward leaning posture compared to the standard posture in asthmatic children. 22 clinically stable asthmatic children, 5-14 years old, performed four reversibility measurements. Children inhaled 200 μg or 400 μg salbutamol with a BAI in the standard or in the forward leaning posture with the neck extended in a randomized single-blinded cross-over design. Reversibility of lung function after inhaling salbutamol in the forward leaning posture was not significantly different compared to inhalation in the standard posture. Mean FEV1 reversibility was significantly greater after inhaling 400 μg salbutamol compared to 200 μg salbutamol in the standard posture (9.4% ± 9.5% versus 4.5% ± 7.5%, difference 4.9% (95CI 0.9; 9.0%); p = 0.021). In clinically stable asthmatic children, inhalation of salbutamol with a BAI in a forward leaning posture does not increase reversibility of lung function. Inhalation of 400 μg compared to 200 μg salbutamol with a BAI does improve reversibility. Copyright © 2015 Elsevier Ltd. All rights reserved.

Altered characteristics of balance control in obese older adults.

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Melzer, Itshak; Oddsson, Lars I E

2016-01-01

Obesity is one of the most significant epidemiological trends of the last decades. Recently it was found that obese individuals show postural instability. Balance control mechanisms in obese older adults were less studied. Therefore we aimed to investigate the effect of obesity on balance control mechanisms in older adults. Parameters from Stabilogram-Diffusion Analysis (SDA) and measures from summary statistics of foot centre-of-pressure (COP) displacements along the anterior-posterior (AP) and mediolateral (ML) directions in eyes open and eyes closed conditions were used to characterize postural control in 22 obese (30-postural control process in obese older adults. A greater sway displacement before closed-loop feedback mechanisms are called into play was seen in the ML direction that may lead to a higher risk of instability and fall events. Copyright © 2015 Asia Oceania Association for the Study of Obesity. Published by Elsevier Ltd. All rights reserved.

Education and the Prevention of Postural Defects

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Olchowska-Kotala Agnieszka

2014-12-01

Full Text Available Purpose. The aim of this study was to determine: whether and at what stage of education is proper body posture learned, the intention of young adults to participate in activities teaching proper posture, and the effects of factors related with the said intention. Methods. The study involved 430 university students aged 18-24 years. Anthropometric data was collected. Participants completed questionnaires assessing physical activity level (IPAQ and their intention to participate in extracurricular activities teaching proper posture while sitting or walking, proper running technique, corrective gymnastics, or weight loss exercises. A self-assessment of posture, physical fitness, attractiveness, and body satisfaction was also completed. Results. Lower back pain was experienced by 41% of the respondents. Most were taught proper posture-related habits in primary school, followed by secondary school, and then at university. Many students expressed their intention to participate in the extracurricular activities. None of the questionnaire variables were associated with the intention to learn proper walking posture or proper running technique. The intention to participate in classes teaching proper sitting posture was associated with lower back pain in women and low physical activity level in men. In women, a relationship was found between the intention to participate in weight loss exercises and body dissatisfaction, high BMI, and poor self-evaluations of posture and attractiveness. In men, this activity was associated with body dissatisfaction. Conclusions. There is a need for further education on the development of proper postural habits at the university level.

Cardiovascular responses to postural changes: differences with age for women and men

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Frey, M. A.; Tomaselli, C. M.; Hoffler, W. G.

1994-01-01

The cardiovascular responses to postural change, and how they are affected by aging, are inadequately described in women. Therefore, the authors examined the influence of age and sex on the responses of blood pressure, cardiac output, heart rate, and other variables to change in posture. Measurements were made after 10 minutes each in the supine, seated, and standing positions in 22 men and 25 women who ranged in age from 21 to 59 years. Several variables differed, both by sex and by age, when subjects were supine. On rising, subjects' diastolic and mean arterial pressures, heart rate, total peripheral resistance (TPR), and thoracic impedance increased; cardiac output, stroke volume, and mean stroke ejection rate decreased; and changes in all variables, except heart rate, were greater from supine to sitting than sitting to standing. The increase in heart rate was greater in the younger subjects, and increases in TPR and thoracic impedance were greater in the older subjects. Stroke volume decreased less, and TPR and thoracic impedance increased more, in the women than in the men. The increase in TPR was particularly pronounced in the older women. These studies show that the cardiovascular responses to standing differ, in some respects, between the sexes and with age. The authors suggest that the sex differences are, in part, related to greater decrease of thoracic blood volume with standing in women than in men, and that the age differences result, in part, from decreased responsiveness of the high-pressure baroreceptor system.

Thermoregulatory postures limit antipredator responses in peafowl

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Jessica L. Yorzinski; Jennifer Lam; Rachel Schultz; Melissa Davis

2018-01-01

Many animals inhabit environments where they experience temperature fluctuations. One way in which animals can adjust to these temperature changes is through behavioral thermoregulation. However, we know little about the thermal benefits of postural changes and the costs they may incur. In this study, we examined the thermoregulatory role of two postures, the head-tuck and leg-tuck posture, in peafowl (Pavo cristatus) and evaluated whether the head-tuck posture imposes a predation cost. The h...

Evaluation of postural stability of people with Parkinson's disease with Biodex Balance System device

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Jacek Wilczyński

2016-10-01

Summary Parkinson's disease is an incurable disease of the CNS of progressive and chronic course. Postural Stability of people with Parkinson's is hindered what predisposes to falls. In a person standing seemingly motionless body performs small oscillatory movements caused by differences in antigravity muscle tension. This mechanism is called postural rocking and mobility associated with it is referred to as postural sway. The parameters of rocking are very sensitive indicator of balance control, and can be used to evaluate and detect pathological changes. The aim of the study was to evaluate the stability of posture of people with Parkinson's disease on the basis of posturographic examination.The age range of the patients was from 52 to 85 years (mean 71.8 years. In terms of age the patients were divided into two groups. The first group consisted of 9 people to 75 years old, while the other of 8 people over 75 years old. The postural stability was assessed with Biodex Balance System. The study was performed at the Laboratory of Posturology at the Institute of Physiotherapy at UJK in Kielce. Although Mann-Whitney U test showed no significant differences in postural stability between the sexes, its lower values are reported for men. A standing position of the subjects was characterized by greater deviation in the sagittal plane than in the frontal plane (A/P>M/L with a tendency to tilt backwards. There were better postural stability results in the younger group (group 1, up to 75 years old. The subjects in this group obtained significantly lower values of postural stability (t°=2.2744, pM/L z tendencją do odchylania się do tyłu. Zaobserwowano lepsze wyniki stabilności posturalnej w grupie osób młodszych (grupa 1 do 75 roku życia. Badani tej grupy uzyskali istotnie niższe wartości stabilności posturalnej (t°= 2,2744, p<0,05.   Słowa kluczowe: stabilność posturalna, choroba Parkinsona, platforma Biodex Balance System

Functional Neuroanatomy for Posture and Gait Control

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Kaoru Takakusaki

2017-01-01

Full Text Available Here we argue functional neuroanatomy for posture- gait control. Multi-sensory information such as somatosensory, visual and vestibular sensation act on various areas of the brain so that adaptable posture- gait control can be achieved. Automatic process of gait, which is steady-state stepping movements associating with postural reflexes including headeye coordination accompanied by appropriate alignment of body segments and optimal level of postural muscle tone, is mediated by the descending pathways from the brainstem to the spinal cord. Particularly, reticulospinal pathways arising from the lateral part of the mesopontine tegmentum and spinal locomotor network contribute to this process. On the other hand, walking in unfamiliar circumstance requires cognitive process of postural control, which depends on knowledges of self-body, such as body schema and body motion in space. The cognitive information is produced at the temporoparietal association cortex, and is fundamental to sustention of vertical posture and construction of motor programs. The programs in the motor cortical areas run to execute anticipatory postural adjustment that is optimal for achievement of goal-directed movements. The basal ganglia and cerebellum may affect both the automatic and cognitive processes of posturegait control through reciprocal connections with the brainstem and cerebral cortex, respectively. Consequently, impairments in cognitive function by damages in the cerebral cortex, basal ganglia and cerebellum may disturb posture-gait control, resulting in falling.

Postural Stability of Special Warfare Combatant-Craft Crewmen With Tactical Gear.

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Morgan, Paul M; Williams, Valerie J; Sell, Timothy C

The US Naval Special Warfare's Special Warfare Combatant-Craft Crewmen (SWCC) operate on small, high-speed boats while wearing tactical gear (TG). The TG increases mission safety and success but may affect postural stability, potentially increasing risk for musculoskeletal injury. Therefore, the purpose of this study was to examine the effects of TG on postural stability during the Sensory Organization Test (SOT). Eight SWCC performed the SOT on NeuroCom's Balance Manager with TG and with no tactical gear (NTG). The status of gear was performed in randomized order. The SOT consisted of six different conditions that challenge sensory systems responsible for postural stability. Each condition was performed for three trials, resulting in a total of 18 trials. Overall performance, each individual condition, and sensory system analysis (somatosensory, visual, vestibular, preference) were scored. Data were not normally distributed therefore Wilcoxon signed-rank tests were used to compare each variable (ρ = .05). No significant differences were found between NTG and TG tests. No statistically significant differences were detected under the two TG conditions. This may be due to low statistical power, or potentially insensitivity of the assessment. Also, the amount and distribution of weight worn during the TG conditions, and the SWCC's unstable occupational platform, may have contributed to the findings. The data from this sample will be used in future research to better understand how TG affects SWCC. The data show that the addition of TG used in our study did not affect postural stability of SWCC during the SOT. Although no statistically significant differences were observed, there are clinical reasons for continued study of the effect of increased load on postural stability, using more challenging conditions, greater surface perturbations, dynamic tasks, and heavier loads. 2016.

Complexity-Based Measures Inform Effects of Tai Chi Training on Standing Postural Control: Cross-Sectional and Randomized Trial Studies

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Wayne, Peter M.; Gow, Brian J.; Costa, Madalena D.; Peng, C.-K.; Lipsitz, Lewis A.; Hausdorff, Jeffrey M.; Davis, Roger B.; Walsh, Jacquelyn N.; Lough, Matthew; Novak, Vera; Yeh, Gloria Y.; Ahn, Andrew C.; Macklin, Eric A.; Manor, Brad

2014-01-01

Background Diminished control of standing balance, traditionally indicated by greater postural sway magnitude and speed, is associated with falls in older adults. Tai Chi (TC) is a multisystem intervention that reduces fall risk, yet its impact on sway measures vary considerably. We hypothesized that TC improves the integrated function of multiple control systems influencing balance, quantifiable by the multi-scale “complexity” of postural sway fluctuations. Objectives To evaluate both traditional and complexity-based measures of sway to characterize the short- and potential long-term effects of TC training on postural control and the relationships between sway measures and physical function in healthy older adults. Methods A cross-sectional comparison of standing postural sway in healthy TC-naïve and TC-expert (24.5±12 yrs experience) adults. TC-naïve participants then completed a 6-month, two-arm, wait-list randomized clinical trial of TC training. Postural sway was assessed before and after the training during standing on a force-plate with eyes-open (EO) and eyes-closed (EC). Anterior-posterior (AP) and medio-lateral (ML) sway speed, magnitude, and complexity (quantified by multiscale entropy) were calculated. Single-legged standing time and Timed-Up–and-Go tests characterized physical function. Results At baseline, compared to TC-naïve adults (n = 60, age 64.5±7.5 yrs), TC-experts (n = 27, age 62.8±7.5 yrs) exhibited greater complexity of sway in the AP EC (P = 0.023), ML EO (Padults. Trial Registration ClinicalTrials.gov NCT01340365 PMID:25494333

The Potential Risk Factors Relevant to Lateral Epicondylitis by Wrist Coupling Posture.

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Su-Ya Lee

Full Text Available The use of awkward wrist postures and unskilled techniques might induce lateral epicondylitis. This study thus investigated the effects of wrist deviation combined with extension and movement velocity on the dynamic performances of the wrist muscles during the coupling posture via a custom-made bi-planar isokinetic dynamometer. Thirty subjects were recruited to perform the isokinetic testing. We measured the muscle strengths and activities for the wrist extensors and flexors during concentric and eccentric contractions at three movement velocities, 30°s-1, 90°s-1, and 180°s-1, combined with three wrist postures, neutral position (NP, radial deviation (RD, and ulnar deviation (UD. The root mean square (RMS of the electromyographic signal in the extensor digitorum communis (EDC, normalized peak torque of extensors, and ratio of normalized peak torque between wrist extensors and flexors, were all greater in the NP than RD and UD in both contractions. The ratio of RMS between EDC and flexor digitorum superficialis (FDS had a significantly greater value in RD than UD during the concentric contraction. The EDC showed significantly higher activity at the fast velocity in both contractions. Nevertheless, a significantly higher RMS of the electromyographic signal between EDC and FDS and the ratio of strength between wrist extensors and flexors were found at slow velocity in both contractions. The wrist deviation combined with extension and movement velocity of the wrist joint should thus be considered as influential factors which might alter the dynamic performances, and may result in further injury of the elbow joint.

Postural Stability of Patients with Schizophrenia during Challenging Sensory Conditions: Implication of Sensory Integration for Postural Control.

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Ya-Ling Teng

Full Text Available Postural dysfunctions are prevalent in patients with schizophrenia and affect their daily life and ability to work. In addition, sensory functions and sensory integration that are crucial for postural control are also compromised. This study intended to examine how patients with schizophrenia coordinate multiple sensory systems to maintain postural stability in dynamic sensory conditions. Twenty-nine patients with schizophrenia and 32 control subjects were recruited. Postural stability of the participants was examined in six sensory conditions of different level of congruency of multiple sensory information, which was based on combinations of correct, removed, or conflicting sensory inputs from visual, somatosensory, and vestibular systems. The excursion of the center of pressure was measured by posturography. Equilibrium scores were derived to indicate the range of anterior-posterior (AP postural sway, and sensory ratios were calculated to explore ability to use sensory information to maintain balance. The overall AP postural sway was significantly larger for patients with schizophrenia compared to the controls [patients (69.62±8.99; controls (76.53±7.47; t1,59 = -3.28, p<0.001]. The results of mixed-model ANOVAs showed a significant interaction between the group and sensory conditions [F5,295 = 5.55, p<0.001]. Further analysis indicated that AP postural sway was significantly larger for patients compared to the controls in conditions containing unreliable somatosensory information either with visual deprivation or with conflicting visual information. Sensory ratios were not significantly different between groups, although small and non-significant difference in inefficiency to utilize vestibular information was also noted. No significant correlations were found between postural stability and clinical characteristics. To sum up, patients with schizophrenia showed increased postural sway and a higher rate of falls during challenging sensory

Wavelet Transform Analysis of the Power Spectrum of Centre of Pressure Signals to Detect the Critical Point Interval of Postural Control

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Singh, Neeraj Kumar; Snoussi, Hichem; Hewson, David; Duchêne, Jacques

The aim of this study was to develop a method to detecting the critical point interval (CPI) when sensory feedback is used as part of a closed-loop postural control strategy. Postural balance was evaluated using centre of pressure (COP) displacements from a force plate for 17 control and 10 elderly subjects under eyes open, eyes closed, and vibration conditions. A modified local-maximum-modulus wavelet transform analysis using the power spectrum of COP signals was used to calculate CPI. Lower CPI values indicate increased closed-loop postural control with a quicker response to sensory input. Such a strategy requires greater energy expenditure due to the repeated muscular interventions to remain stable. The CPI for elderly occurred significantly quicker than for controls, indicating tighter control of posture. Similar results were observed for eyes closed and vibration conditions. The CPI parameter can be used to detect differences in postural control due to ageing.

Postural adjustments are modulated by manual task complexity

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Luis Augusto Teixeira

2009-09-01

Full Text Available Daily life activities of humans are characterized by dual tasks, in which a manual task is performed concomitantly with a postural task. Based on the assumption that both manual and postural tasks require attentional resources, no consensus exists as to how the central nervous system modulates postural adjustments in dual tasks. The aim of the present study was to analyze the effect of a manual task requiring attentional resources on shoulder and ankle adjustments as a function of the direction and predictability of postural perturbation. The participants (n=6 were evaluated during the performance of a simple and a complex manual task, while the base of support was moved backward or forward. Latency of activation of the tibialis anterior and gastroc-nemius muscles and angular acceleration of the shoulder were analyzed. The results showed that execution of the complex manual task delayed postural adjustment. Moreover, this delay occurred differently depending on the direction of postural perturbation. The delay in postural adjustment occurred proximally in the case of anterior displacement of the platform, and distally in the case of posterior displacement. Postural adjustments were more affected by the attentional task than by the predictability of platform displacement. These results are consistent with the concept of an integrated control between manual actions and the maintenance of static posture.

The effects of brief swaying on postural control.

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Pagé, Sara; Maheu, Maxime; Landry, Simon P; Champoux, François

2017-12-06

Postural control can be improved with balance training. However, the nature and duration of the training required to enhance posture remains unclear. We studied the effects of 5 min of a self-initiated balance exercise along a single axis on postural control in healthy individuals. Postural control was measured before and after a 5-min period where members of the experimental group were asked to lean their entire body forward and backward and members of the control group were asked to remain seated. A significant improvement for sway velocity, a postural control variable significantly associated with an increased risk of falls, was found in the experimental group following the body sway exercise. These data suggest that a basic exercise can rapidly improve postural control and reduce the risk of falls.

Activation timing of postural muscles of lower legs and prediction of postural disturbance during bilateral arm flexion in older adults.

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Yaguchi, Chie; Fujiwara, Katsuo; Kiyota, Naoe

2017-12-22

Activation timings of postural muscles of lower legs and prediction of postural disturbance were investigated in young and older adults during bilateral arm flexion in a self-timing task and an oddball task with different probabilities of target presentation. Arm flexion was started from a standing posture with hands suspended 10 cm below the horizontal level in front of the body, in which postural control focused on the ankles is important. Fourteen young and 14 older adults raised the arms in response to the target sound signal. Three task conditions were used: 15 and 45% probabilities of the target in the oddball task and self-timing. Analysis items were activation timing of postural muscles (erector spinae, biceps femoris, and gastrocnemius) with respect to the anterior deltoid (AD), and latency and amplitude of the P300 component of event-related brain potential. For young adults, all postural muscles were activated significantly earlier than AD under each condition, and time of preceding gastrocnemius activation was significantly longer in the order of the self-timing, 45 and 15% conditions. P300 latency was significantly shorter, and P300 amplitude was significantly smaller under the 45% condition than under the 15% condition. For older adults, although all postural muscles, including gastrocnemius, were activated significantly earlier than AD in the self-timing condition, only activation timing of gastrocnemius was not significantly earlier than that of AD in oddball tasks, regardless of target probability. No significant differences were found between 15 and 45% conditions in onset times of all postural muscles, and latency and amplitude of P300. These results suggest that during arm movement, young adults can achieve sufficient postural preparation in proportion to the probability of target presentation in the oddball task. Older adults can achieve postural control using ankle joints in the self-timing task. However, in the oddball task, older adults

A research on the postural stability of a person wearing the lower limb exoskeletal robot by the HAT model.

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Chang, Minsu; Kim, Yeongmin; Lee, Yoseph; Jeon, Doyoung

2017-07-01

This paper proposes a method of detecting the postural stability of a person wearing the lower limb exoskeletal robot with the HAT(Head-Arm-Trunk) model. Previous studies have shown that the human posture is stable when the CoM(Center of Mass) of the human body is placed on the BoS(Base of Support). In the case of the lower limb exoskeletal robot, the motion data, which are used for the CoM estimation, are acquired by sensors in the robot. The upper body, however, does not have sensors in each segment so that it may cause the error of the CoM estimation. In this paper, the HAT(Head-Arm-Trunk) model which combines head, arms, and torso into a single segment is considered because the motion of head and arms are unknown due to the lack of sensors. To verify the feasibility of HAT model, the reflecting markers are attached to each segment of the whole human body and the exact motion data are acquired by the VICON to compare the COM of the full body model and HAT model. The difference between the CoM with full body and that with HAT model is within 20mm for the various motions of head and arms. Based on the HAT model, the XCoM(Extrapolated Center of Mass) which includes the velocity of the CoM is used for prediction of the postural stability. The experiment of making unstable posture shows that the XCoM of the whole body based on the HAT model is feasible to detect the instance of postural instability earlier than the CoM by 20-250 msec. This result may be used for the lower limb exoskeletal robot to prepare for any action to prevent the falling down.

Neuromechanical tuning of nonlinear postural control dynamics

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Ting, Lena H.; van Antwerp, Keith W.; Scrivens, Jevin E.; McKay, J. Lucas; Welch, Torrence D. J.; Bingham, Jeffrey T.; DeWeerth, Stephen P.

2009-06-01

Postural control may be an ideal physiological motor task for elucidating general questions about the organization, diversity, flexibility, and variability of biological motor behaviors using nonlinear dynamical analysis techniques. Rather than presenting "problems" to the nervous system, the redundancy of biological systems and variability in their behaviors may actually be exploited to allow for the flexible achievement of multiple and concurrent task-level goals associated with movement. Such variability may reflect the constant "tuning" of neuromechanical elements and their interactions for movement control. The problem faced by researchers is that there is no one-to-one mapping between the task goal and the coordination of the underlying elements. We review recent and ongoing research in postural control with the goal of identifying common mechanisms underlying variability in postural control, coordination of multiple postural strategies, and transitions between them. We present a delayed-feedback model used to characterize the variability observed in muscle coordination patterns during postural responses to perturbation. We emphasize the significance of delays in physiological postural systems, requiring the modulation and coordination of both the instantaneous, "passive" response to perturbations as well as the delayed, "active" responses to perturbations. The challenge for future research lies in understanding the mechanisms and principles underlying neuromechanical tuning of and transitions between the diversity of postural behaviors. Here we describe some of our recent and ongoing studies aimed at understanding variability in postural control using physical robotic systems, human experiments, dimensional analysis, and computational models that could be enhanced from a nonlinear dynamics approach.

Obesity impact on the attentional cost for controlling posture.

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Jean-Baptiste Mignardot

2010-12-01

Full Text Available This study investigated the effects of obesity on attentional resources allocated to postural control in seating and unipedal standing.Ten non obese adults (BMI = 22.4±1.3, age = 42.4±15.1 and 10 obese adult patients (BMI = 35.2±2.8, age = 46.2±19.6 maintained postural stability on a force platform in two postural tasks (seated and unipedal. The two postural tasks were performed (1 alone and (2 in a dual-task paradigm in combination with an auditory reaction time task (RT. Performing the RT task together with the postural one was supposed to require some attentional resources that allowed estimating the attentional cost of postural control. 4 trials were performed in each condition for a total of 16 trials.(1 Whereas seated non obese and obese patients exhibited similar centre of foot pressure oscillations (CoP, in the unipedal stance only obese patients strongly increased their CoP sway in comparison to controls. (2 Whatever the postural task, the additional RT task did not affect postural stability. (3 Seated, RT did not differ between the two groups. (4 RT strongly increased between the two postural conditions in the obese patients only, suggesting that body schema and the use of internal models was altered with obesity.Obese patients needed more attentional resources to control postural stability during unipedal stance than non obese participants. This was not the case in a more simple posture such as seating. To reduce the risk of fall as indicated by the critical values of CoP displacement, obese patients must dedicate a strong large part of their attentional resources to postural control, to the detriment of non-postural events. Obese patients were not able to easily perform multitasking as healthy adults do, reflecting weakened psycho-motor abilities.

Obesity Impact on the Attentional Cost for Controlling Posture

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Mignardot, Jean-Baptiste; Olivier, Isabelle; Promayon, Emmanuel; Nougier, Vincent

2010-01-01

Background This study investigated the effects of obesity on attentional resources allocated to postural control in seating and unipedal standing. Methods Ten non obese adults (BMI = 22.4±1.3, age = 42.4±15.1) and 10 obese adult patients (BMI = 35.2±2.8, age = 46.2±19.6) maintained postural stability on a force platform in two postural tasks (seated and unipedal). The two postural tasks were performed (1) alone and (2) in a dual-task paradigm in combination with an auditory reaction time task (RT). Performing the RT task together with the postural one was supposed to require some attentional resources that allowed estimating the attentional cost of postural control. 4 trials were performed in each condition for a total of 16 trials. Findings (1) Whereas seated non obese and obese patients exhibited similar centre of foot pressure oscillations (CoP), in the unipedal stance only obese patients strongly increased their CoP sway in comparison to controls. (2) Whatever the postural task, the additional RT task did not affect postural stability. (3) Seated, RT did not differ between the two groups. (4) RT strongly increased between the two postural conditions in the obese patients only, suggesting that body schema and the use of internal models was altered with obesity. Interpretation Obese patients needed more attentional resources to control postural stability during unipedal stance than non obese participants. This was not the case in a more simple posture such as seating. To reduce the risk of fall as indicated by the critical values of CoP displacement, obese patients must dedicate a strong large part of their attentional resources to postural control, to the detriment of non-postural events. Obese patients were not able to easily perform multitasking as healthy adults do, reflecting weakened psycho-motor abilities. PMID:21187914

A flexed posture in elderly patients is associated with impairments in postural control during walking.

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de Groot, Maartje H; van der Jagt-Willems, Hanna C; van Campen, Jos P C M; Lems, Willem F; Beijnen, Jos H; Lamoth, Claudine J C

2014-02-01

A flexed posture (FP) is characterized by protrusion of the head and an increased thoracic kyphosis (TK), which may be caused by osteoporotic vertebral fractures (VFs). These impairments may affect motor function, and consequently increase the risk of falling and fractures. The aim of the current study was therefore to examine postural control during walking in elderly patients with FP, and to investigate the relationship with geriatric phenomena that may cause FP, such as increased TK, VFs, frailty, polypharmacy and cognitive impairments. Fifty-six elderly patients (aged 80 ± 5.2 years; 70% female) walked 160 m at self-selected speed while trunk accelerations were recorded. Walking speed, mean stride time and coefficient of variation (CV) of stride time were recorded. In addition, postural control during walking was quantified by time-dependent variability measures derived from the theory of stochastic dynamics, indicating smoothness, degree of predictability, and local stability of trunk acceleration patterns. Twenty-five patients (45%) had FP and demonstrated a more variable and less structured gait pattern, and a more irregular trunk acceleration pattern than patients with normal posture. FP was significantly associated with an increased TK, but not with other geriatric phenomena. An increased TK may bring the body's centre of mass forward, which requires correcting responses, and reduces the ability to respond on perturbation, which was reflected by higher variation in the gait pattern in FP-patients. Impairments in postural control during walking are a major risk factor for falling: the results indicate that patients with FP have impaired postural control during walking and might therefore be at increased risk of falling. Copyright © 2013 Elsevier B.V. All rights reserved.

Effects of vision and cognitive load on static postural control in subjects with and without patellofemoral pain syndrome.

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Zeinalzadeh, Afsaneh; Talebian, Saeed; Naghdi, Soofia; Salavati, Mahyar; Nazary-Moghadam, Salman; Zeynalzadeh Ghoochani, Bahareh

2018-04-01

To compare the effects of vision and cognitive load on static postural control in subjects with and without patellofemoral pain syndrome (PFPS). Twenty-eight PFPS patients and 28 controls participated in the study. Postural control was assessed in isolation as well as with visual manipulation and cognitive loading on symptomatic limb. The outcome measures of postural control were quantified in terms of area, anterior-posterior (AP), medial-lateral (ML), and mean velocity (MV) of the displacements of center of pressure (COP). In addition, cognitive performance (auditory Stroop task) was measured in the forms of average reaction time and error ratio in baseline (sitting) and different postural conditions. PFPS subjects showed greater increases in area (p = 0.01), AP (p = 0.01), and ML (p = 0.05) displacements of COP in the blindfolded tasks as compared to control group. However, cognitive load did not differently affect postural control in the two groups. Although PFPS and control group had similar reaction times in the sitting position (p = 0.29), PFPS subjects had longer reaction times than healthy subjects in dual task conditions (p = 0.04). Visual inputs seem to be essential for discriminating postural control between PFPS and healthy individuals. PFPS patients biased toward decreasing cognitive performance more than healthy subjects when they perform the single leg stance and cognitive task concurrently.

The dentist’s operating posture – ergonomic aspects

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Pîrvu, C; Pătraşcu, I; Pîrvu, D; Ionescu, C

2014-01-01

Abstract The practice of dentistry involves laborious high finesse dental preparations, precision and control in executions that require a particular attention, concentration and patience of the dentist and finally the dentist’s physical and mental resistance. The optimal therapeutic approach and the success of practice involve special working conditions for the dentist and his team in an ergonomic environment. The meaning of the posture in ergonomics is the manner in which different parts of the body are located and thus the reports are established between them in order to allow a special task execution. This article discusses the posture adopted by dentists when they work, beginning with the balanced posture and going to different variants of posture. The ideal posture of a dentist gives him, on the one hand the optimal working conditions (access, visibility and control in the mouth) and on the other hand, physical and psychological comfort throughout the execution of the clinical acts. Although the theme of dentist posture is treated with great care and often presented in the undergraduate courses and the continuing education courses on ergonomics in dentistry, many dentists do not know the subject well enough nor the theoretical issues and therefore nor the practical applicability. The risk and perspective of the musculoskeletal disorders related to unbalanced postures should determine the dentists take postural corrective actions and compensation measures in order to limit the negative effects of working in a bad posture. PMID:25184007

USE OF SOFTWARES FOR POSTURE ASSESSMENT: INTEGRATIVE REVIEW

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Edyla Maria Porto de Freitas Camelo

2015-09-01

Full Text Available To carry out an integrative literature review on the postural analysis softwares available today. It is an integrative-narrative review of qualitative and methodological nature performed during April-July 2014. As inclusion criteria, the articles should be bibliographical or original research and available with full access. At first, we proceeded to the identification of the keywords for the softwares related to postural assessment commonly used in the health field, in such case "posture", "software", and "postural assessment". The search was narrowed by publication date from 2002 to 2014. Through the information acquired from the articles and from the software developers, information on 12 programs that assist the postural evaluation were obtained - Alcimage, All Body Scan 3D, Aplob, APPID, Biotonix, Corporis Pro, Fisimetrix, Fisiometer Posturograma, Physical Fisio, Physio Easy, Posture Print and SAPO. However, only one tool has more information and studies, namely SAPO. There are many postural analysis softwares available on the internet today, however, these are quite disparate in relation to possible answers and are still poorly widespread as research tools.

Effects of rapid maxillary expansion on head posture, postural stability, and fall risk

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Fatih Celebi

2017-01-01

Full Text Available Objective: The aim of this study was to investigate the effects of rapid maxillary expansion (RME on head posture, postural stability, and fall risk. Materials and Methods: A sample of 51 adolescent patients was randomly divided into two groups. In the first group, which consisted of 28 patients (15 females and 13 males, RME was performed as a part of routine orthodontic treatment. The remaining 23 individuals (12 females and 11 males served as the control group. Lateral cephalometric radiographs taken in natural head position, postural stability, and fall risk scores were obtained during the first visit. They were repeated on average 3.8 months and 3.5 months later for the study and control groups, respectively. The changes were analyzed using the Wilcoxon signed-rank test, paired samples t-test, Mann–Whitney U-test, and independent samples t-test. Results: As a result of RME, a statistically significant decrease was detected in the fall risk score (P < 0.05 in the study group, while the head position and postural stability remained unchanged. For the control group, no significant changes were observed in all measurements. Conclusions: The result of the present study suggests that RME has a capacity of improving fall risk.

Combination of BTrackS and Geri-Fit as a targeted approach for assessing and reducing the postural sway of older adults with high fall risk.

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Goble, Daniel J; Hearn, Mason C; Baweja, Harsimran S

2017-01-01

Atypically high postural sway measured by a force plate is a known risk factor for falls in older adults. Further, it has been shown that small, but significant, reductions in postural sway are possible with various balance exercise interventions. In the present study, a new low-cost force-plate technology called the Balance Tracking System (BTrackS) was utilized to assess postural sway of older adults before and after 90 days of a well-established exercise program called Geri-Fit. Results showed an overall reduction in postural sway across all participants from pre- to post-intervention. However, the magnitude of effects was significantly influenced by the amount of postural sway demonstrated by individuals prior to Geri-Fit training. Specifically, more participants with atypically high postural sway pre-intervention experienced an overall postural sway reduction. These reductions experienced were typically greater than the minimum detectable change statistic for the BTrackS Balance Test. Taken together, these findings suggest that BTrackS is an effective means of identifying older adults with elevated postural sway, who are likely to benefit from Geri-Fit training to mitigate fall risk.

[Head posture in orthodontics: physiopathology and clinical aspects 2].

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Caltabiano, M; Verzi, P; Scire Scappuzzo, G

1989-01-01

The Authors review in orthodontic respects present knowledges about head posture involvement in craniofacial morphogenesis and pathology. Relationships between craniofacial morphology, craniocervical posture, craniomandibular posture, cervical spine curvature, hyoid bone position and posture of whole body in space are shown, in attempt to explain conditions such as "forward head posture", mouth breathing and some occlusal disorders. Main methods to evaluate craniocervical relations on lateral skull radiographs are analysed. Pathogenesis of pain syndromes associated with abnormal craniocervical and craniomandibular mechanics are also briefly treated.

Relationship between craniomandibular disorders and poor posture.

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Nicolakis, P; Nicolakis, M; Piehslinger, E; Ebenbichler, G; Vachuda, M; Kirtley, C; Fialka-Moser, V

2000-04-01

The purpose of this research was to show that a relationship between craniomandibular disorders (CMD) and postural abnormalities has been repeatedly postulated, but still remains unproven. This study was intended to test this hypothesis. Twenty-five CMD patients (mean age 28.2 years) were compared with 25 gender and age matched controls (mean age 28.3 years) in a controlled, investigator-blinded trial. Twelve postural and ten muscle function parameters were examined. Measurements were separated into three subgroups, consisting of those variables associated with the cervical region, the trunk in the frontal plane, and the trunk in the sagittal plane. Within these subgroups, there was significantly more dysfunction in the patients, compared to control subjects (Mann-Whitney U test p Postural and muscle function abnormalities appeared to be more common in the CMD group. Since there is evidence of the mutual influence of posture and the craniomandibular system, control of body posture in CMD patients is recommended, especially if they do not respond to splint therapy. Whether poor posture is the reason or the result of CMD cannot be distinguished by the data presented here.

Resistance versus Balance Training to Improve Postural Control in Parkinson's Disease: A Randomized Rater Blinded Controlled Study.

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Schlenstedt, Christian; Paschen, Steffen; Kruse, Annika; Raethjen, Jan; Weisser, Burkhard; Deuschl, Günther

2015-01-01

Reduced muscle strength is an independent risk factor for falls and related to postural instability in individuals with Parkinson's disease. The ability of resistance training to improve postural control still remains unclear. To compare resistance training with balance training to improve postural control in people with Parkinson's disease. 40 patients with idiopathic Parkinson's disease (Hoehn&Yahr: 2.5-3.0) were randomly assigned into resistance or balance training (2x/week for 7 weeks). Assessments were performed at baseline, 8- and 12-weeks follow-up: primary outcome: Fullerton Advanced Balance (FAB) scale; secondary outcomes: center of mass analysis during surface perturbations, Timed-up-and-go-test, Unified Parkinson's Disease Rating Scale, Clinical Global Impression, gait analysis, maximal isometric leg strength, PDQ-39, Beck Depression Inventory. Clinical tests were videotaped and analysed by a second rater, blind to group allocation and assessment time. 32 participants (resistance training: n = 17, balance training: n = 15; 8 drop-outs) were analyzed at 8-weeks follow-up. No significant difference was found in the FAB scale when comparing the effects of the two training types (p = 0.14; effect size (Cohen's d) = -0.59). Participants from the resistance training group, but not from the balance training group significantly improved on the FAB scale (resistance training: +2.4 points, Cohen's d = -0.46; balance training: +0.3 points, Cohen's d = -0.08). Within the resistance training group, improvements of the FAB scale were significantly correlated with improvements of rate of force development and stride time variability. No significant differences were found in the secondary outcome measures when comparing the training effects of both training types. The difference between resistance and balance training to improve postural control in people with Parkinson's disease was small and not significant with this sample size. There was weak evidence that freely

Resistance versus Balance Training to Improve Postural Control in Parkinson's Disease: A Randomized Rater Blinded Controlled Study.

Directory of Open Access Journals (Sweden)

Christian Schlenstedt

Full Text Available Reduced muscle strength is an independent risk factor for falls and related to postural instability in individuals with Parkinson's disease. The ability of resistance training to improve postural control still remains unclear.To compare resistance training with balance training to improve postural control in people with Parkinson's disease.40 patients with idiopathic Parkinson's disease (Hoehn&Yahr: 2.5-3.0 were randomly assigned into resistance or balance training (2x/week for 7 weeks. Assessments were performed at baseline, 8- and 12-weeks follow-up: primary outcome: Fullerton Advanced Balance (FAB scale; secondary outcomes: center of mass analysis during surface perturbations, Timed-up-and-go-test, Unified Parkinson's Disease Rating Scale, Clinical Global Impression, gait analysis, maximal isometric leg strength, PDQ-39, Beck Depression Inventory. Clinical tests were videotaped and analysed by a second rater, blind to group allocation and assessment time.32 participants (resistance training: n = 17, balance training: n = 15; 8 drop-outs were analyzed at 8-weeks follow-up. No significant difference was found in the FAB scale when comparing the effects of the two training types (p = 0.14; effect size (Cohen's d = -0.59. Participants from the resistance training group, but not from the balance training group significantly improved on the FAB scale (resistance training: +2.4 points, Cohen's d = -0.46; balance training: +0.3 points, Cohen's d = -0.08. Within the resistance training group, improvements of the FAB scale were significantly correlated with improvements of rate of force development and stride time variability. No significant differences were found in the secondary outcome measures when comparing the training effects of both training types.The difference between resistance and balance training to improve postural control in people with Parkinson's disease was small and not significant with this sample size. There was weak evidence that

The reliability and validity of the Saliba Postural Classification System.

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Collins, Cristiana Kahl; Johnson, Vicky Saliba; Godwin, Ellen M; Pappas, Evangelos

2016-07-01

To determine the reliability and validity of the Saliba Postural Classification System (SPCS). Two physical therapists classified pictures of 100 volunteer participants standing in their habitual posture for inter and intra-tester reliability. For validity, 54 participants stood on a force plate in a habitual and a corrected posture, while a vertical force was applied through the shoulders until the clinician felt a postural give. Data were extracted at the time the give was felt and at a time in the corrected posture that matched the peak vertical ground reaction force (VGRF) in the habitual posture. Inter-tester reliability demonstrated 75% agreement with a Kappa = 0.64 (95% CI = 0.524-0.756, SE = 0.059). Intra-tester reliability demonstrated 87% agreement with a Kappa = 0.8, (95% CI = 0.702-0.898, SE = 0.05) and 80% agreement with a Kappa = 0.706, (95% CI = 0.594-0818, SE = 0.057). The examiner applied a significantly higher (p < 0.001) peak vertical force in the corrected posture prior to a postural give when compared to the habitual posture. Within the corrected posture, the %VGRF was higher when the test was ongoing vs. when a postural give was felt (p < 0.001). The %VGRF was not different between the two postures when comparing the peaks (p = 0.214). The SPCS has substantial agreement for inter- and intra-tester reliability and is largely a valid postural classification system as determined by the larger vertical forces in the corrected postures. Further studies on the correlation between the SPCS and diagnostic classifications are indicated.

Instability following total knee arthroplasty.

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Rodriguez-Merchan, E Carlos

2011-10-01

Background Knee prosthesis instability (KPI) is a frequent cause of failure of total knee arthroplasty. Moreover, the degree of constraint required to achieve immediate and long-term stability in total knee arthroplasty (TKA) is frequently debated. Questions This review aims to define the problem, analyze risk factors, and review strategies for prevention and treatment of KPI. Methods A PubMed (MEDLINE) search of the years 2000 to 2010 was performed using two key words: TKA and instability. One hundred and sixty-five initial articles were identified. The most important (17) articles as judged by the author were selected for this review. The main criteria for selection were that the articles addressed and provided solutions to the diagnosis and treatment of KPI. Results Patient-related risk factors predisposing to post-operative instability include deformity requiring a large surgical correction and aggressive ligament release, general or regional neuromuscular pathology, and hip or foot deformities. KPI can be prevented in most cases with appropriate selection of implants and good surgical technique. When ligament instability is anticipated post-operatively, the need for implants with a greater degree of constraint should be anticipated. In patients without significant varus or valgus malalignment and without significant flexion contracture, the posterior cruciate ligament (PCL) can be retained. However, the PCL should be sacrificed when deformity exists particularly in patients with rheumatoid arthritis, previous patellectomy, previous high tibial osteotomy or distal femoral osteotomy, and posttraumatic osteoarthritis with disruption of the PCL. In most cases, KPI requires revision surgery. Successful outcomes can only be obtained if the cause of KPI is identified and addressed. Conclusions Instability following TKA is a common cause of the need for revision. Typically, knees with deformity, rheumatoid arthritis, previous patellectomy or high tibial osteotomy, and

Ergonomic strategies to improve radiographers' posture during mammography activities.

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Cernean, Nicolai; Serranheira, Florentino; Gonçalves, Pedro; Sá Dos Reis, Cláudia

2017-08-01

To identify alternatives for radiographers' postures while performing mammography that can contribute to reduce the risk of work-related musculoskeletal disorders (WRMSDs). Radiographers' postures to positioning craniocaudal (CC) and mediolateral oblique (MLO) views were simulated without any intervention for three scenarios: radiographer/patient with similar statures, radiographer smaller than patient and radiographer taller than patient. Actions were taken to modify the postures: seated radiographer; patient on a step; seated patient; radiographer on a step. All the postures were analysed using kinovea 0.8.15 software and the angles were measured twice and classified according to European standard EN1005-4: 2005. The non-acceptable angles were measured mainly during MLO positioning when radiographer was taller than the patient: 139° and 120° for arm-flexion and abduction, 72° for trunk and -24° for head/neck-flexion. The introduction of alternative postures (radiographer seated), allowed improvements in posture (60° and 99° for arm flexion and abduction, 14° for trunk and 0° for head/neck flexion), being classified as acceptable. The alternative postures simulated have the potential to reduce the risk of developing WRMSDs when radiographers and patients have different statures. • Radiographers' postures in mammography can contribute to work-related musculoskeletal disorders • Non-acceptable posture was identified for MLO breast positioning (radiographer taller than patient) • Adapting posture to patient biotype reduces the WRMSD risk for radiographers.

Physiological Mechanisms Mediating the Coupling between Heart Period and Arterial Pressure in Response to Postural Changes in Humans

NARCIS (Netherlands)

Silvani, A.; Calandra-Buonaura, G.; Johnson, B.D.; Helmond, N. van; Barletta, G.; Cecere, A.G.; Joyner, M.J.; Cortelli, P.

2017-01-01

The upright posture strengthens the coupling between heart period (HP) and systolic arterial pressure (SAP) consistently with a greater contribution of the arterial baroreflex to cardiac control, while paradoxically decreasing cardiac baroreflex sensitivity (cBRS). To investigate the physiological

Posture-specific phantoms representing female and male adults in Monte Carlo-based simulations for radiological protection

Science.gov (United States)

Cassola, V. F.; Kramer, R.; Brayner, C.; Khoury, H. J.

2010-08-01

Does the posture of a patient have an effect on the organ and tissue absorbed doses caused by x-ray examinations? This study aims to find the answer to this question, based on Monte Carlo (MC) simulations of commonly performed x-ray examinations using adult phantoms modelled to represent humans in standing as well as in the supine posture. The recently published FASH (female adult mesh) and MASH (male adult mesh) phantoms have the standing posture. In a first step, both phantoms were updated with respect to their anatomy: glandular tissue was separated from adipose tissue in the breasts, visceral fat was separated from subcutaneous fat, cartilage was segmented in ears, nose and around the thyroid, and the mass of the right lung is now 15% greater than the left lung. The updated versions are called FASH2_sta and MASH2_sta (sta = standing). Taking into account the gravitational effects on organ position and fat distribution, supine versions of the FASH2 and the MASH2 phantoms have been developed in this study and called FASH2_sup and MASH2_sup. MC simulations of external whole-body exposure to monoenergetic photons and partial-body exposure to x-rays have been made with the standing and supine FASH2 and MASH2 phantoms. For external whole-body exposure for AP and PA projection with photon energies above 30 keV, the effective dose did not change by more than 5% when the posture changed from standing to supine or vice versa. Apart from that, the supine posture is quite rare in occupational radiation protection from whole-body exposure. However, in the x-ray diagnosis supine posture is frequently used for patients submitted to examinations. Changes of organ absorbed doses up to 60% were found for simulations of chest and abdomen radiographs if the posture changed from standing to supine or vice versa. A further increase of differences between posture-specific organ and tissue absorbed doses with increasing whole-body mass is to be expected.

Assessing Somatosensory Utilization during Unipedal Postural Control

OpenAIRE

Goel, Rahul; De Dios, Yiri E.; Gadd, Nichole E.; Caldwell, Erin E.; Peters, Brian T.; Reschke, Millard F.; Bloomberg, Jacob J.; Oddsson, Lars I. E.; Mulavara, Ajitkumar P.

2017-01-01

Multisensory—visual, vestibular and somatosensory information is integrated for appropriate postural control. The primary goal of this study was to assess somatosensory utilization during a functional motor task of unipedal postural control, in normal healthy adults. Assessing individual bias in the utilization of individual sensory contributions during postural control may help customization of rehabilitation protocols. In this study, a test paradigm of unipedal stance control in supine orie...

Postural Control in Children: Implications for Pediatric Practice

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Westcott, Sarah L.; Burtner, Patricia

2004-01-01

Based on a systems theory of motor control, reactive postural control (RPA) and anticipatory postural control (APA) in children are reviewed from several perspectives in order to develop an evidence-based intervention strategy for improving postural control in children with limitations in motor function. Research on development of postural…

Decrease in back strength in asymmetric trunk postures

NARCIS (Netherlands)

Vink, P.; Daanen, H. A M; Meijst, W. J.; Ligteringen, J.

1992-01-01

The extension force against resistance was recorded in 23 postures for 12 subjects to find explanations for the decrease in back strength in asymmetric postures. A reduction in muscle force in asymmetric postures was found up to 40%, but was strongly dependent on the plane in which asymmetry

Investigating the Effects of Different Working Postures on Cognitive Performance

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Sharareh Mohammadi

2018-01-01

Conclusion This study demonstrates that cognitive performance is affected by working postures. This study demonstrates that standard sitting posture is the best posture. Therefore, it is recommended that sitting posture can help in increasing cognitive performance in the workplace.

Age-related differences in norepinephrine kinetics: Effect of posture and sodium-restricted diet

International Nuclear Information System (INIS)

Supiano, M.A.; Linares, O.A.; Smith, M.J.; Halter, J.B.

1990-01-01

We used compartmental analysis to study the influence of age on the kinetics of norepinephrine (NE) distribution and metabolism. Plasma NE and [3H]NE levels were measured in 10 young (age 19-33 yr) and 13 elderly (age 62-73 yr) subjects in the basal supine position, during upright posture, and after 1 wk of a sodium-restricted diet. We found that the basal supine release rate of NE into the extravascular compartment, which is the site of endogenous NE release (NE2), was significantly increased in the elderly group (young, 9.6 +/- 0.5; elderly, 12.3 +/- 0.8 nmol.min-1.m-2; means +/- SE; P = 0.016), providing direct evidence for an age-related increase in sympathetic nervous system (SNS) tone. Although upright posture led to a greater increase in plasma NE in the young (0.90 +/- 0.07 to 2.36 +/- 0.16 nM) than in the elderly (1.31 +/- 0.11 to 2.56 +/- 0.31 nM; age group-posture interaction, P = 0.02), the increase in NE2 was similar between the young (9.6 +/- 0.6 to 16.2 +/- 1.5 nmol.min-1.m-2) and the elderly (11.6 +/- 1.4 to 16.1 +/- 2.4 nmol.min-1.m-2; posture effect, P = 0.001; age group-posture interaction, P = 0.15). Thus the increase in SNS tone resulting from upright posture was similar in young and elderly subjects. Plasma NE levels increased similarly in both groups after a sodium-restricted diet (diet effect, P = 0.001; age group-diet interaction, P = 0.23). However, NE2 did not increase significantly in either group (diet effect, P = 0.26), suggesting that SNS tone did not increase after a sodium-restricted diet. Compartmental analysis provides a description of age-related differences in NE kinetics, including an age-related increase in the extravascular NE release rate

Affective instability as a clinical feature of avoidant personality disorder.

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Snir, Avigal; Bar-Kalifa, Eran; Berenson, Kathy R; Downey, Geraldine; Rafaeli, Eshkol

2017-10-01

The current study's main goal was to examine whether affective instability is elevated among individuals suffering from avoidant personality disorder (APD) by comparing it to the affective instability found among individuals suffering from borderline personality disorder (BPD) as well that found among healthy controls. Adults (N = 152, aged 18-65 years) with BPD, APD, or no psychopathology participated in a 3-week computerized diary study. We examined temporal instability in negative affect using experience-sampling methods. Both within and between days, individuals with APD showed greater affective instability compared to the healthy control individuals, although less affective instability compared to individuals with BPD. The findings are in line with affective instability (or emotional lability) as a key dimension relevant across personality disorders. Additionally, they emphasize the need for research and clinical attention to affective characteristics (alongside the more readily recognized interpersonal characteristics) of APD. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Testing postural control among various osteoporotic patient groups: a literature review.

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de Groot, Maartje H; van der Jagt-Willems, Hanna C; van Campen, Jos P C M; Lems, Willem F; Lamoth, Claudine J C

2012-10-01

Osteoporosis can cause vertebral fractures, which might lead to a flexed posture, impaired postural control and consequently increased fall risk. Therefore, the aim of the present review was to examine whether postural control of patients with osteoporosis, vertebral fractures, thoracic kyphosis and flexed posture is affected. Furthermore, instruments measuring postural control were evaluated and examined for sensitivity and easy clinical use. Until February 2011, electronic databases were systematically searched for cross-sectional studies. Methodological quality was assessed with a modified Downs & Black scale. Of the 518 found studies, 18 studies were included. Postural control was generally affected for patients with vertebral fractures, thoracic kyphosis and flexed posture. Patients with osteoporosis had impaired postural control when assessed with computerized instruments. Easy performance-based tests did not show any impairments. There is evidence for an impaired postural control in all patient groups included. Impaired postural control is an important risk factor for falls. Functional performance tests are not sensitive and specific enough to detect affected postural control in patients with osteoporosis. To detect impaired postural control among osteoporotic patients and to obtain more insight into the underlying mechanisms of postural control, computerized instruments are recommended, such as easy-to-use ambulant motion-sensing (accelerometry) technology. © 2012 Japan Geriatrics Society.

Feedback control of resistive instabilities

International Nuclear Information System (INIS)

White, R.B.; Rutherford, P.H.; Furth, H.P.; Park, W.; Chen, L.

1985-12-01

Resistive instabilities are responsible for much of the global behavior and the determination of the possible domains of operation of tokamaks. Their successful control could have definite advantages, even making available new regimes of operation. Elimination of sawtoothing might allow operation with higher currents and more peaked current profiles, with q on axis well below unity. In this work different feedback schemes are explored. Simple analytical derivations of the effects of local heating and current drive feedback are presented. Although control of modes with m greater than or equal to 2 is fairly straightforward, the control of the m = 1 mode is more difficult because of its proximity to ideal instability. The most promising scheme utilizes high energy trapped particles. 20 refs., 3 figs

Effectiveness of neuromuscular taping on pronated foot posture and walking plantar pressures in amateur runners.

Science.gov (United States)

Aguilar, María Bravo; Abián-Vicén, Javier; Halstead, Jill; Gijon-Nogueron, Gabriel

2016-04-01

To determine the effect kinesiotaping (KT) versus sham kinesiotaping (sham KT) in the repositioning of pronated feet after a short running. Prospective, randomised, double-blinded, using a repeated-measures design with no cross-over. 116 amateur runners were screened by assessing the post-run (45min duration) foot posture to identify pronated foot types (defined by Foot Posture Index [FPI] score of ≥6). Seventy-three runners met the inclusion criteria and were allocated into two treatment groups, KT (n=49) and sham KT (n=24). After applying either the KT or sham KT and completing 45min of running (mean speed of 12km/h), outcome measures were collected (FPI and walking Pedobarography). FPI was reduced in both groups, more so in the KT group (mean FPI between group difference=0.9, CI 0.1-1.9), with a score closer to neutral. There were statistically significant differences between KT and sham KT (p<.05 and p<.01) in pressure time integral, suggesting that sham KT had a greater effect. KT may be of some assistant to clinicians in correction of pronated foot posture in a short-term. There was no effect of KT, however on pressure variables at heel strike or toe-off following a short duration of running, the sham KT technique had a greater effect. Therapy, level 1b. Copyright © 2015 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Voluntarily controlled but not merely observed visual feedback affects postural sway

Science.gov (United States)

Asai, Tomohisa; Hiromitsu, Kentaro; Imamizu, Hiroshi

2018-01-01

Online stabilization of human standing posture utilizes multisensory afferences (e.g., vision). Whereas visual feedback of spontaneous postural sway can stabilize postural control especially when observers concentrate on their body and intend to minimize postural sway, the effect of intentional control of visual feedback on postural sway itself remains unclear. This study assessed quiet standing posture in healthy adults voluntarily controlling or merely observing visual feedback. The visual feedback (moving square) had either low or high gain and was either horizontally flipped or not. Participants in the voluntary-control group were instructed to minimize their postural sway while voluntarily controlling visual feedback, whereas those in the observation group were instructed to minimize their postural sway while merely observing visual feedback. As a result, magnified and flipped visual feedback increased postural sway only in the voluntary-control group. Furthermore, regardless of the instructions and feedback manipulations, the experienced sense of control over visual feedback positively correlated with the magnitude of postural sway. We suggest that voluntarily controlled, but not merely observed, visual feedback is incorporated into the feedback control system for posture and begins to affect postural sway. PMID:29682421

Development of low postural tone compensatory patterns in children - theoretical basis.

Science.gov (United States)

Gogola, Anna; Saulicz, Edward; Kuszewski, Michał; Matyja, Małgorzata; Myśliwiec, Andrzej

2014-01-01

Neurological literature indicates the existence of children with low postural tone without association with central nervous system damage. This fact induces to think about mechanisms, which allow these children to maintain upright posture. There is a suspicion that compensatory mechanism included in this process, enables to achieve upright posture, but at expense of body posture quality. Observations of children's developmental stages caused determination of some postural tone area, which comprise both children with normotonia and with low postural tone without characteristics of central nervous system (CNS) damage. Set of specific qualities allows determination of two types of low postural tone: spastoidal and atetoidal type. Spastoidal type is characterized by deep trunk muscles (local) low postural tone compensated by excessive tension of superficial muscles (global). Atetoidal type includes children with low postural tone in both deep and superficial muscles. At inefficient active subsystem, verticalization proceeds at excessive use of passive subsystem qualities, that is meniscus, ligament, bone shape, and muscles passive features. From neurodevelopmental point of view compensatory mechanisms can be used in children with low postural tone in order to achieve upright posture, but at expense of body posture quality.

Static postural balance in healthy individuals: Comparisons between three age groups

Directory of Open Access Journals (Sweden)

Yanne Salviano Pereira

2014-03-01

Full Text Available The aim of the study was to compare static postural balance of healthy individuals of three age groups in different conditions of support and vision. Seventy one individuals, divided into 3 groups, were analyzed: young group (YG: 22.2 ± 2.1 years, middle aged group (MAG: 50.7 ± 5.7 years and older individuals group (EG: 66.8 ± 5.4 years. Their balance was tested on a force platform, under 3 support and 3 visual conditions. Measures included: total (TD, anterior-posterior (APD and mediolateral displacement (MLD of the center of pressure (CoP. ANOVA revealed significant differences for interactions between group X support conditions and group X visual conditions for the 3 variables (p<0.01, with greater displacements for the MAG and EG groups during single-leg stance with partial and occluded vision (p<0.05. Static postural balance decreased over time in healthy individuals, and conditions of support and visual negatively affected balance with the increment of age.

Anatomy and histochemistry of spread-wing posture in birds. I. Wing drying posture in the double-crested cormorant, Phalacrocorax auritus.

Science.gov (United States)

Meyers, Ron A

1997-07-01

Spread-wing postures of birds often have been studied with respect to the function of behavior, but ignored with regard to the mechanism by which the birds accomplish posture. The double-crested cormorant, Phalacrocorax auritus, was used as a model for this study of spread-wing posture. Those muscles capable of positioning and maintaining the wing in extension and protraction were assayed histochemically for the presence of slow (postural) muscle fibers. Within the forelimb of Phalacrocorax, Mm. coracobrachialis cranialis, pectoralis thoracicus (cranial portion), deltoideus minor, triceps scapularis, and extensor metacarpi radialis pars dorsalis and ventralis were found to contain populations of slow-twitch or slow-tonic muscle fibers. These slow fibers in the above muscles are considered to function during spread-wing posture in this species. J Morphol 233:67-76, 1997. © 1997 Wiley-Liss, Inc. Copyright © 1997 Wiley-Liss, Inc.

Sit still and pay attention: Using the Wii Balance-Board to detect lapses in concentration in children during psychophysical testing.

Science.gov (United States)

Jones, Pete R

2018-05-16

During psychophysical testing, a loss of concentration can cause observers to answer incorrectly, even when the stimulus is clearly perceptible. Such lapses limit the accuracy and speed of many psychophysical measurements. This study evaluates an automated technique for detecting lapses based on body movement (postural instability). Thirty-five children (8-11 years of age) and 34 adults performed a typical psychophysical task (orientation discrimination) while seated on a Wii Fit Balance Board: a gaming device that measures center of pressure (CoP). Incorrect responses on suprathreshold catch trials provided the "reference standard" measure of when lapses in concentration occurred. Children exhibited significantly greater variability in CoP on lapse trials, indicating that postural instability provides a feasible, real-time index of concentration. Limitations and potential applications of this method are discussed.

Posture Detection Based on Smart Cushion for Wheelchair Users

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Congcong Ma

2017-03-01

Full Text Available The postures of wheelchair users can reveal their sitting habit, mood, and even predict health risks such as pressure ulcers or lower back pain. Mining the hidden information of the postures can reveal their wellness and general health conditions. In this paper, a cushion-based posture recognition system is used to process pressure sensor signals for the detection of user’s posture in the wheelchair. The proposed posture detection method is composed of three main steps: data level classification for posture detection, backward selection of sensor configuration, and recognition results compared with previous literature. Five supervised classification techniques—Decision Tree (J48, Support Vector Machines (SVM, Multilayer Perceptron (MLP, Naive Bayes, and k-Nearest Neighbor (k-NN—are compared in terms of classification accuracy, precision, recall, and F-measure. Results indicate that the J48 classifier provides the highest accuracy compared to other techniques. The backward selection method was used to determine the best sensor deployment configuration of the wheelchair. Several kinds of pressure sensor deployments are compared and our new method of deployment is shown to better detect postures of the wheelchair users. Performance analysis also took into account the Body Mass Index (BMI, useful for evaluating the robustness of the method across individual physical differences. Results show that our proposed sensor deployment is effective, achieving 99.47% posture recognition accuracy. Our proposed method is very competitive for posture recognition and robust in comparison with other former research. Accurate posture detection represents a fundamental basic block to develop several applications, including fatigue estimation and activity level assessment.

Relationship between Postural Deformities and Frontal Function in Parkinson's Disease

OpenAIRE

Ninomiya, Satoko; Morita, Akihiko; Teramoto, Hiroko; Akimoto, Takayoshi; Shiota, Hiroshi; Kamei, Satoshi

2015-01-01

Postural deformities and executive dysfunction (ED) are common symptoms of Parkinson's disease (PD); however, the relationship between postural deformities and ED in patients with PD remains unclear. This study assessed the relationship between postural deformities and ED in patients with PD. Sixty-five patients with sporadic PD were assessed for the severity of postural deformities and executive function. The severity of postural deformities was scored using the United Parkinson's Disease Ra...

PENINGKATAN STABILITAS POSTURAL PADA LANSIA MELALUI BALANCE EXERCISE

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Kusnanto .

2010-12-01

Full Text Available Stabilitas postural adalah masalah yang umum pada lansia. Balance exercise dapat dijadikan alternative latihan bagi lansia. Latihan ini meliputi 5 gerakan (plantar flexion, hip flexion, hip flexion, knee flexion dan side leg raise. Penelitian ini bertujuan untuk menganalisa efek dari balance exercise terhadap peningkatan stabilitas postural pada lansia. Penelitian ini menggunakan design pre eksperimen. Populasi yang digunakan adalah lansia di Panti Wreda Bangkalan. Total sampel adalah 11 responden, yang diambil berdasarkan kriteria inklusi. Variabel dependen adalah balance exercise dan variabel independen adalah stabilitas postural. Stabilitas postural diukur menggunakan 2 tes, yaitu tes Tinetti dan TUGT (Time Up and Go Test. Data dianalisa menggunakan paired t test dengan level signifikan 0,05. Hasil penelitian menunjukkan bahwa balance exercise secara signifikan dapat meningkatkan stabilitas postural. Pada tes Tinetti (p=0,000 dan di TUGT (p=0,001. Sehingga dapat disimpulkan bahwa terdapat hasil yang signifikan antara balance exercise dengan peningkatan stabilitas postural pada lansia. Hal ini disebabkan Karena balance exercise dapat membuat otot lansia menjadi hipertrofi. Hipertrofi dapat meningkatkan kekuatan otot sehingga stabilitas postural lansia dapat meningkat. Penelitian yang akan datang diharapkan melibatkan lebih banyak responden dengan waktu penelitian yang lebih lama dan pengukuran yang lebih baik untuk memastikan hasil yang lebih akurat.

Clinical evaluation of postural posture of patients with previous stroke subjected to early rehabilitation

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Anna Sagan

2018-02-01

Full Text Available Introduction: Impairment disorders are often found in patients with stroke and impairment of motor and cognitive functions. This is a very serious complication because, by imposing a motor impairment, it aggravates the condition of disability and makes it difficult to conduct physical rehabilitation.The resulting neurological deficits due to stroke determine functional disorders. The possibility of locomotion is usually compromised, therefore the risk of falls increases significantly. The aim of the work is to present Postural Assesment Scale for Strock PASS with the postural stroke assessment scale, the impact of early rehabilitation of patients staying in the neurology ward.Material and methods: Postural examination was carried out among 17 people, of which 8 were women, and 9 were male. The study was divided into two stages. The first stage occurred immediately after the stroke and the second one before the patient was discharged from the ward. Research was carried out at the Biegański Specialist Hospital in Grudziądz in the Department of Neurology and Clinical Neuroimmunology and Impact Department.Conclusions: The results of the postural studies carried out in people with previous stroke subjected to early physiotherapy have a beneficial effect of the conducted therapy. There are positive changes between the first and the final examination of the patients.

Static and dynamic postural control in low-vision and normal-vision adults.

Science.gov (United States)

Tomomitsu, Mônica S V; Alonso, Angelica Castilho; Morimoto, Eurica; Bobbio, Tatiana G; Greve, Julia M D

2013-04-01

This study aimed to evaluate the influence of reduced visual information on postural control by comparing low-vision and normal-vision adults in static and dynamic conditions. Twenty-five low-vision subjects and twenty-five normal sighted adults were evaluated for static and dynamic balance using four protocols: 1) the Modified Clinical Test of Sensory Interaction on Balance on firm and foam surfaces with eyes opened and closed; 2) Unilateral Stance with eyes opened and closed; 3) Tandem Walk; and 4) Step Up/Over. The results showed that the low-vision group presented greater body sway compared with the normal vision during balance on a foam surface (p≤0.001), the Unilateral Stance test for both limbs (p≤0.001), and the Tandem Walk test. The low-vision group showed greater step width (p≤0.001) and slower gait speed (p≤0.004). In the Step Up/Over task, low-vision participants were more cautious in stepping up (right p≤0.005 and left p≤0.009) and in executing the movement (p≤0.001). These findings suggest that visual feedback is crucial for determining balance, especially for dynamic tasks and on foam surfaces. Low-vision individuals had worse postural stability than normal-vision adults in terms of dynamic tests and balance on foam surfaces.

Postural changes in obese and non-obese children and adolescents. 10.5007/1980-0037.2011v13n6p448

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Larissa Rosa da Silva

2011-11-01

Full Text Available Obesity has reached epidemic proportions over recent years and is related to cardiovascular risk factors, as well as to the occurrence of postural changes in adults, children and adolescents. The objective of this study was to identify the prevalence of postural abnormalities and pain in schoolchildren. Fifty-one children and adolescents of both genders aged 9-17 years were divided into an obese (n = 33 and a non-obese group (n = 18. Weight and height were measured to calculate the body mass index. A questionnaire was used to assess the presence or absence of pain. Postural deviations of the shoulder, head and knees were analyzed by photometry using the Corel Draw12 software for the determination of angular measures and size. Obese boys showed greater postural changes in the region of the knees than non-obese ones (p<0.001. No significant differences in any of the regions analyzed were observed for girls. On the other hand, the prevalence of pain was significantly higher among obese girls than among non-obese girls. We conclude that postural changes are not limited to obese children, but excess weight may increase this deviation. Further studies are needed to diagnose these changes during childhood in order to permit early intervention and good posture in adult life.

Postural balance in low back pain patients

DEFF Research Database (Denmark)

Maribo, Thomas; Schiøttz-Christensen, Berit; Jensen, Lone Donbæk

2012-01-01

INTRODUCTION: Altered postural control has been observed in low back pain (LBP) patients. They seem to be more dependent on vision when standing. The objective of the study was to determine concurrent and predictive validity of measures of postural stability in LBP patients. MATERIALS AND METHODS......: Centre of Pressure (CoP) measurements were tested against pain, fear of pain, and physical function. Velocity, anterior-posterior displacement, and the Romberg Ratio obtained on a portable force platform were used as measures of postural stability. RESULTS: Baseline and 12-week follow-up results of 97....... CONCLUSION: This first study of concurrent and predictive validity of postural balance in LBP patients revealed no association between CoP measures and pain, fear of pain, and physical function....

Combination of BTrackS and Geri-Fit as a targeted approach for assessing and reducing the postural sway of older adults with high fall risk

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Goble DJ

2017-02-01

Full Text Available Daniel J Goble, Mason C Hearn, Harsimran S Baweja School of Exercise and Nutritional Sciences, College of Health and Human Services, San Diego State University, San Diego, CA, USA Abstract: Atypically high postural sway measured by a force plate is a known risk factor for falls in older adults. Further, it has been shown that small, but significant, reductions in postural sway are possible with various balance exercise interventions. In the present study, a new low-cost force-plate technology called the Balance Tracking System (BTrackS was utilized to assess postural sway of older adults before and after 90 days of a well-established exercise program called Geri-Fit. Results showed an overall reduction in postural sway across all participants from pre- to post-intervention. However, the magnitude of effects was significantly influenced by the amount of postural sway demonstrated by individuals prior to Geri-Fit training. Specifically, more participants with atypically high postural sway pre-intervention experienced an overall postural sway reduction. These reductions experienced were typically greater than the minimum detectable change statistic for the BTrackS Balance Test. Taken together, these findings suggest that BTrackS is an effective means of identifying older adults with elevated postural sway, who are likely to benefit from Geri-Fit training to mitigate fall risk. Keywords: aging, balance, BTrackS, Geri-Fit, postural sway, fall risk

Relationship between Postural Deformities and Frontal Function in Parkinson’s Disease

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Satoko Ninomiya

2015-01-01

Full Text Available Postural deformities and executive dysfunction (ED are common symptoms of Parkinson’s disease (PD; however, the relationship between postural deformities and ED in patients with PD remains unclear. This study assessed the relationship between postural deformities and ED in patients with PD. Sixty-five patients with sporadic PD were assessed for the severity of postural deformities and executive function. The severity of postural deformities was scored using the United Parkinson’s Disease Rating Scale item 28 score: no postural deformity (0, mild postural deformities (1, or severe postural deformities (2–4. Executive function was assessed using the Behavioral Assessment of the Dysexecutive Syndrome (BADS and an age-controlled standardized BADS score <70 was defined as ED. Age-controlled standardized BADS scores were compared across the three groups using the Kruskal-Wallis test. Relationship between ED and the severity of postural deformities was assessed using the Mann-Whitney U test. Age-controlled standardized BADS score significantly differed among the three groups P=0.005. ED was significantly related to the severity of postural deformities P=0.0005. The severity of postural deformities was associated with a lower age-controlled standardized BADS score and ED, and these findings suggest that postural deformities were associated with frontal dysfunction in patients with PD.

Inactivity periods and postural change speed can explain atypical postural change patterns of Caenorhabditis elegans mutants.

Science.gov (United States)

Fukunaga, Tsukasa; Iwasaki, Wataru

2017-01-19

With rapid advances in genome sequencing and editing technologies, systematic and quantitative analysis of animal behavior is expected to be another key to facilitating data-driven behavioral genetics. The nematode Caenorhabditis elegans is a model organism in this field. Several video-tracking systems are available for automatically recording behavioral data for the nematode, but computational methods for analyzing these data are still under development. In this study, we applied the Gaussian mixture model-based binning method to time-series postural data for 322 C. elegans strains. We revealed that the occurrence patterns of the postural states and the transition patterns among these states have a relationship as expected, and such a relationship must be taken into account to identify strains with atypical behaviors that are different from those of wild type. Based on this observation, we identified several strains that exhibit atypical transition patterns that cannot be fully explained by their occurrence patterns of postural states. Surprisingly, we found that two simple factors-overall acceleration of postural movement and elimination of inactivity periods-explained the behavioral characteristics of strains with very atypical transition patterns; therefore, computational analysis of animal behavior must be accompanied by evaluation of the effects of these simple factors. Finally, we found that the npr-1 and npr-3 mutants have similar behavioral patterns that were not predictable by sequence homology, proving that our data-driven approach can reveal the functions of genes that have not yet been characterized. We propose that elimination of inactivity periods and overall acceleration of postural change speed can explain behavioral phenotypes of strains with very atypical postural transition patterns. Our methods and results constitute guidelines for effectively finding strains that show "truly" interesting behaviors and systematically uncovering novel gene

Compromising Postural Balance in the Elderly

NARCIS (Netherlands)

Swanenburg, Jaap; de Bruin, Eling D.; Uebelhart, Daniel; Mulder, Theo

2009-01-01

Background: Additional tasks that are assumed to disturb standing postural control can be divided in added motor or added cognitive tasks. It is unknown which type of task causes the most disturbances of postural control in elderly. Objective: The aim of this study was to determine whether the dual

Posture and Texting: Effect on Balance in Young Adults.

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Nurul Retno Nurwulan

Full Text Available Using a mobile phone while doing another activity is a common dual-task activity in our daily lives. This study examined the effect of texting on the postural stability of young adults. Twenty college students were asked to perform static and dynamic postural stability tasks. Traditional COP and multivariate multiscale entropy (MMSE were used to assess the static postural stability and the Star Excursion Balance Test (SEBT was used to assess the dynamic postural stability. Results showed that (1 texting impaired postural stability, (2 the complexity index did not change much although the task conditions changed, and (3 performing texting is perceived to be more difficult.

Falls efficacy, postural balance, and risk for falls in older adults with falls-related emergency department visits: prospective cohort study.

Science.gov (United States)

Pua, Yong-Hao; Ong, Peck-Hoon; Clark, Ross Allan; Matcher, David B; Lim, Edwin Choon-Wyn

2017-12-21

Risk for falls in older adults has been associated with falls efficacy (self-perceived confidence in performing daily physical activities) and postural balance, but available evidence is limited and mixed. We examined the interaction between falls efficacy and postural balance and its association with future falls. We also investigated the association between falls efficacy and gait decline. Falls efficacy, measured by the Modified Falls Efficacy Scale (MFES), and standing postural balance, measured using computerized posturography on a balance board, were obtained from 247 older adults with a falls-related emergency department visit. Six-month prospective fall rate and habitual gait speed at 6 months post baseline assessment were also measured. In multivariable proportional odds analyses adjusted for potential confounders, falls efficacy modified the association between postural balance and fall risk (interaction P = 0.014): increasing falls efficacy accentuated the increased fall risk related to poor postural balance. Low baseline falls efficacy was strongly predictive of worse gait speed (0.11 m/s [0.06 to 0.16] slower gait speed per IQR decrease in MFES; P falls efficacy but poor postural balance were at greater risk for falls than those with low falls efficacy; however, low baseline falls efficacy was strongly associated with worse gait function at follow-up. Further research into these subgroups of older adults is warranted. ClinicalTrials.gov identifier: NCT01713543 .

Postural Response Signal Characteristics Identified by Method of Developed Statokinesigram

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Barbolyas Boris

2015-12-01

Full Text Available Human postural system is taken as complex biological system with specific input and output time characteristics, in this study. Evaluation of measured output characteristics is useful in medical diagnostics or in describing postural system disorders. System theory principle provide suitable basis for postural signals analysis. Participating volunteers were instructed to maintain quiet upright stance posture on firm support surface of stabilometric platform for 60s. Postural system actuation was realized by vibration stimuli applied bilaterally on Achilles tendons for 20s. Postural reaction signal, its time profile and static and dynamic characteristics were evaluated by Method of Developed Statokinesigram Trajectory (MDST.

Head movements and postures as pain behavior

Science.gov (United States)

Al-Hamadi, Ayoub; Limbrecht-Ecklundt, Kerstin; Walter, Steffen; Traue, Harald C.

2018-01-01

Pain assessment can benefit from observation of pain behaviors, such as guarding or facial expression, and observational pain scales are widely used in clinical practice with nonverbal patients. However, little is known about head movements and postures in the context of pain. In this regard, we analyze videos of three publically available datasets. The BioVid dataset was recorded with healthy participants subjected to painful heat stimuli. In the BP4D dataset, healthy participants performed a cold-pressor test and several other tasks (meant to elicit emotion). The UNBC dataset videos show shoulder pain patients during range-of-motion tests to their affected and unaffected limbs. In all videos, participants were sitting in an upright position. We studied head movements and postures that occurred during the painful and control trials by measuring head orientation from video over time, followed by analyzing posture and movement summary statistics and occurrence frequencies of typical postures and movements. We found significant differences between pain and control trials with analyses of variance and binomial tests. In BioVid and BP4D, pain was accompanied by head movements and postures that tend to be oriented downwards or towards the pain site. We also found differences in movement range and speed in all three datasets. The results suggest that head movements and postures should be considered for pain assessment and research. As additional pain indicators, they possibly might improve pain management whenever behavior is assessed, especially in nonverbal individuals such as infants or patients with dementia. However, in advance more research is needed to identify specific head movements and postures in pain patients. PMID:29444153

Different patterns of spontaneous brain activity between tremor-dominant and postural instability/gait difficulty subtypes of Parkinson's disease: a resting-state fMRI study.

Science.gov (United States)

Chen, Hui-Min; Wang, Zhi-Jiang; Fang, Jin-Ping; Gao, Li-Yan; Ma, Ling-Yan; Wu, Tao; Hou, Ya-Nan; Zhang, Jia-Rong; Feng, Tao

2015-10-01

Postural instability/gait difficulty (PIGD) and tremor-dominant (TD) subtypes of Parkinson's disease (PD) show different clinical manifestations; however, their underlying neural substrates remain incompletely understood. This study aimed at investigating the subtype-specific patterns of spontaneous brain activity in PD. Thirty-one patients with PD (12 TD/19 PIGD) and 22 healthy gender- and age-matched controls were recruited. Resting-state functional magnetic resonance imaging data were collected, and amplitude of low-frequency fluctuations (ALFF) was measured. Voxelwise one-way analysis of covariance and post hoc analyses of ALFF were performed among the three groups, with age and gender as covariates (levodopa daily dosage and gray matter volume as additional covariates for validation analysis). Correlations of clinical variables (e.g., disease duration and PIGD/tremor subscale score) with ALFF values were examined. Compared with controls, patients with TD exhibited higher ALFF in the right cerebellar posterior lobe and patients with PIGD exhibited lower ALFF in the bilateral putamen and cerebellar posterior lobe, and higher values primarily in several cortical areas including the inferior and superior temporal gyrus, superior frontal, and parietal gyrus. Compared with patients with PIGD, patients with TD had higher ALFF in the bilateral putamen and the cerebellar posterior lobe, as well as lower ALFF in the bilateral temporal gyrus and the left superior parietal lobule. In all patients, ALFF in the bilateral cerebellar posterior lobe positively correlated with tremor score and ALFF in the bilateral putamen negatively correlated with PIGD score. Different patterns of spontaneous neural activity in the cerebellum and putamen may underlie the neural substrate of PD motor subtypes. © 2015 John Wiley & Sons Ltd.

External load application in gait and posture reeducation after diffuse axonal injury of the corpus callosum. A case report

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Magdalena Zawadka

2018-06-01

Full Text Available Traumatic brain injury caused car accidents is the one of the most common causes of diffuse axonal injury typically located at the grey-white matter junction, in the corpus callosum. A 58-year-old female patient Caucasian race was admitted to the Orthopedic and Rehabilitation Unit with head injury, broken right ulnar bone, numerous broken ribs and broken right iliac crest. Neurological examination resulted in right-sided hemiparesis. There were also coordination and balance disorders while sitting and standing. The patient was unable to walk. After physiotherapy treatment included external load application (ankle weights and rucksack with weights in gait and posture reeducation, patient has improved balance, locomotion and body posture. However, application of external loads during walk and posture reeducation needs to be further investigated with greater number of participants and control group.

Effects of disease severity and medication state on postural control asymmetry during challenging postural tasks in individuals with Parkinson's disease.

Science.gov (United States)

Barbieri, Fabio A; Polastri, Paula F; Baptista, André M; Lirani-Silva, Ellen; Simieli, Lucas; Orcioli-Silva, Diego; Beretta, Victor S; Gobbi, Lilian T B

2016-04-01

The aim of this study was to investigate the effects of disease severity and medication state on postural control asymmetry during challenging tasks in individuals with Parkinson's disease (PD). Nineteen people with PD and 11 neurologically healthy individuals performed three standing task conditions: bipedal standing, tandem and unipedal adapted standing; the individuals with PD performed the tasks in ON and OFF medication state. The participants with PD were distributed into 2 groups according to disease severity: unilateral group (n=8) and bilateral group (n=11). The two PD groups performed the evaluations both under and without the medication. Two force plates were used to analyze the posture. The symmetric index was calculated for various of center of pressure. ANOVA one-way (groups) and two-way (PD groups×medication), with repeated measures for medication, were calculated. For main effects of group, the bilateral group was more asymmetric than CG. For main effects of medication, only unipedal adapted standing presented effects of PD medication. There was PD groups×medication interaction. Under the effects of medication, the unilateral group presented lower asymmetry of RMS in anterior-posterior direction and area than the bilateral group in unipedal adapted standing. In addition, the unilateral group presented lower asymmetry of mean velocity, RMS in anterior-posterior direction and area in unipedal standing and area in tandem adapted standing after a medication dose. Postural control asymmetry during challenging postural tasks was dependent on disease severity and medication state in people with PD. The bilateral group presented higher postural control asymmetry than the control and unilateral groups in challenging postural tasks. Finally, the medication dose was able to reduce postural control asymmetry in the unilateral group during challenging postural tasks. Copyright © 2015 Elsevier B.V. All rights reserved.

An investigation into essential aspects of posture in primary school ...

African Journals Online (AJOL)

Postures of the subjects were analysed by means of photographic images using the pro forma of Barlow (1956, 1990). The majority of the executives had malposture with 2.3%, 23.3%, 58.1% and 16.3% and 6.3% of the subjects being categorised with slight postural defects, severe postural defects, very severe postural ...

Instability after total hip arthroplasty

Science.gov (United States)

Werner, Brian C; Brown, Thomas E

2012-01-01

Instability following total hip arthroplasty (THA) is an unfortunately frequent and serious problem that requires thorough evaluation and preoperative planning before surgical intervention. Prevention through optimal index surgery is of great importance, as the management of an unstable THA is challenging even for an experienced joints surgeon. However, even after well-planned surgery, a significant incidence of recurrent instability still exists. Non-operative management is often successful if the components are well-fixed and correctly positioned in the absence of neurocognitive disorders. If conservative management fails, surgical options include revision of malpositioned components; exchange of modular components such as the femoral head and acetabular liner; bipolar arthroplasty; tripolar arthroplasty; use of a larger femoral head; use of a constrained liner; soft tissue reinforcement and advancement of the greater trochanter. PMID:22919568

Review on two-phase flow instabilities in narrow spaces

International Nuclear Information System (INIS)

Tadrist, L.

2007-01-01

Instabilities in two-phase flow have been studied since the 1950s. These phenomena may appear in power generation and heat transfer systems where two-phase flow is involved. Because of thermal management in small size systems, micro-fluidics plays an important role. Typical processes must be considered when the channel hydraulic diameter becomes very small. In this paper, a brief review of two-phase flow instabilities encountered in channels having hydraulic diameters greater than 10 mm are presented. The main instability types are discussed according to the existing experimental results and models. The second part of the paper examines two-phase flow instabilities in narrow spaces. Pool and flow boiling cases are considered. Experiments as well as theoretical models existing in the literature are examined. It was found that several experimental works evidenced these instabilities meanwhile only limited theoretical developments exist in the literature. In the last part of the paper an interpretation of the two-phase flow instabilities linked to narrow spaces are presented. This approach is based on characteristic time scales of the two-phase flow and bubble growth in the capillaries

Altered postural control strategies in quiet standing more than 20 years after rupture of the anterior cruciate ligament.

Science.gov (United States)

Stensdotter, Ann-Katrin; Tengman, Eva; Häger, Charlotte

2016-05-01

To explore long-term consequences of anterior cruciate ligament (ACL) rupture on postural sway and control strategies during bilateral quiet standing, in subjects treated with or without reconstructive surgery compared to uninjured controls. 70 individuals who had unilateral ACL rupture 23±2.4 years ago (33 received ACL reconstructive surgery, ACLR, and 37 had physiotherapy only, ACLPT) and 33 uninjured matched controls (CTRL) (mean age 46±5.3) stood quietly with eyes closed for 3min on a firm and on a compliant surface, respectively. Center of pressure (CoP) was registered with a force plate and postural sway was calculated from center of mass (CoM) derived from 3D kinematics. Sway density (SD) analyses of CoP assessed distance and duration of stable phases. The torque controlling postural sway was estimated from CoP-CoM. Comparisons across conditions to CTRL revealed larger CoP-CoM-area in ACLR (p=0.017, CI: 10.95, 143.10), but not in ACLPT. Mean distance between SD-peaks was greater for ACLR (ppostural control efforts than CTRL but without significant differences in postural sway. Control efforts were thus not directly associated with sway and further research should be focused on variance in postural control strategies. Copyright © 2016. Published by Elsevier B.V.

Postural changes in obese and non-obese children and adolescents.DOI:10.5007/1980-0037.2011v13n6p448

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Larissa Rosa da Silva

2011-11-01

Full Text Available Obesity has reached epidemic proportions over recent years and is related to cardiovascular risk factors, as well as to the occurrence of postural changes in adults, children and adolescents. The objective of this study was to identify the prevalence of postural abnormalities and pain in schoolchildren. Fifty-one children and adolescents of both genders aged 9-17 years were divided into an obese (n = 33 and a non-obese group (n = 18. Weight and height were measured to calculate the body mass index. A questionnaire was used to assess the presence or absence of pain. Postural deviations of the shoulder, head and knees were analyzed by photometry using the Corel Draw12 software for the determination of angular measures and size. Obese boys showed greater postural changes in the region of the knees than non-obese ones (p<0.001. No significant differences in any of the regions analyzed were observed for girls. On the other hand, the prevalence of pain was significantly higher among obese girls than among non-obese girls. We conclude that postural changes are not limited to obese children, but excess weight may increase this deviation. Further studies are needed to diagnose these changes during childhood in order to permit early intervention and good posture in adult life.

Vibration-enhanced posture stabilization achieved by tactile supplementation: may blind individuals get extra benefits?

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Magalhães, Fernando Henrique; Kohn, André Fabio

2011-08-01

Diminished balance ability poses a serious health risk due to the increased likelihood of falling, and impaired postural stability is significantly associated with blindness and poor vision. Noise stimulation (by improving the detection of sub-threshold somatosensory information) and tactile supplementation (i.e., additional haptic information provided by an external contact surface) have been shown to improve the performance of the postural control system. Moreover, vibratory noise added to the source of tactile supplementation (e.g., applied to a surface that the fingertip touches) has been shown to enhance balance stability more effectively than tactile supplementation alone. In view of the above findings, in addition to the well established consensus that blind subjects show superior abilities in the use of tactile information, we hypothesized that blind subjects may take extra benefits from the vibratory noise added to the tactile supplementation and hence show greater improvements in postural stability than those observed for sighted subjects. If confirmed, this hypothesis may lay the foundation for the development of noise-based assistive devices (e.g., canes, walking sticks) for improving somatosensation and hence prevent falls in blind individuals. Copyright © 2011 Elsevier Ltd. All rights reserved.

Association between temporomandibular disorders and abnormal head postures

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Evandro Francisco FAULIN

2015-01-01

Full Text Available This study examines the possible correlation between the prevalence of temporomandibular disorders (TMD and different head postures in the frontal and sagittal planes using photographs of undergraduate students in the School of Dentistry at the Universidade de Brasília - UnB, Brazil. In this nonrandomized, cross-sectional study, the diagnoses of TMD were made with the Research Diagnostic Criteria (RDC/TMD axis I. The craniovertebral angle was used to evaluate forward head posture in the sagittal plane, and the interpupillary line was used to measure head tilt in the frontal plane. The measurements to evaluate head posture were made using the Software for the Assessment of Posture (SAPO. Students were divided into two study groups, based on the presence or absence of TMD. The study group comprised 46 students and the control group comprised 80 students. Data about head posture and TMD were analyzed with the Statistical Package for the Social Sciences, version 13. Most cases of TMD were classified as degenerative processes (group III, followed by disk displacement (group II and muscle disorders (group I. There was no sex predominance for the type of disorder. No association was found between prevalence rates for head postures in the frontal plane and the occurrence of TMD. The same result was found for the association of TMD diagnosis with craniovertebral angle among men and women, and the group that contained both men and women. Abnormal head postures were common among individuals both with and without TMD. No association was found between head posture evaluated in the frontal and sagittal planes and TMD diagnosis with the use of RDC/TMD.

Characterization of postural control impairment in women with fibromyalgia

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Sempere-Rubio, Núria; López-Pascual, Juan; Aguilar-Rodríguez, Marta; Cortés-Amador, Sara; Espí-López, Gemma; Villarrasa-Sapiña, Israel

2018-01-01

The main goal of this cross-sectional study was to detect whether women with fibromyalgia syndrome (FMS) have altered postural control and to study the sensory contribution to postural control. We also explored the possibility that self-induced anxiety and lower limb strength may be related to postural control. For this purpose, 129 women within an age range of 40 to 70 years were enrolled. Eighty of the enrolled women had FMS. Postural control variables, such as Ellipse, Root mean square (RMS) and Sample entropy (SampEn), in both directions (i.e. mediolateral and anteroposterior), were calculated under five different conditions. A force plate was used to register the center of pressure shifts. Furthermore, isometric lower limb strength was recorded with a portable dynamometer and normalized by lean body mass. The results showed that women with FMS have impaired postural control compared with healthy people, as they presented a significant increase in Ellipse and RMS values (pPostural control also worsens with the gradual alteration of sensory inputs in this population (p0.05). There were no significant correlations between postural control and lower limb strength (p>0.05). Therefore, women with FMS have impaired postural control that is worse when sensory inputs are altered but is not correlated with their lower limb strength. PMID:29723223

Effect of magnification loupes on dental hygiene student posture.

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Maillet, J Peggy; Millar, A Michele; Burke, Jillian M; Maillet, Michelle A; Maillet, Wayne A; Neish, Nancy R

2008-01-01

The chair-side work posture of dental hygienists has long been a concern because of health-related problems potentially caused or exacerbated by poor posture. The purpose of this study was to investigate if using magnification loupes improved dental hygiene students' posture during provision of treatment. The treatment chosen was hand-scaling, and the effect of the timing of introduction of the loupes to students was also examined. Thirty-five novice dental hygiene students took part in the study. Each student was assessed providing dental hygiene care with and without loupes, thus controlling for innate differences in natural posture. Students were randomized into two groups. Group one used loupes in the first session and did not use them for the second session. Group two reversed this sequence. At the end of each session, all students were videotaped while performing scaling procedures. Their posture was assessed using an adapted version of Branson et al.'s Posture Assessment Instrument (PAI). Four raters assessed students at three time periods for nine posture components on the PAI. A paired t-test compared scores with and without loupes for each student. Scores showed a significant improvement in posture when using loupes (ppostural benefit is realized by requiring students to master the use of magnification loupes as early as possible within the curriculum.

Nintendo Wii training on postural balance and mobility rehabilitation of adults with Parkinson's disease: a systematic review

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Daniel Dominguez Ferraz

Full Text Available Abstract Introduction: Postural instability affects balance control in Parkinson disease (PD patients and increases the particular risk of falling compared with healthy older adults. Video games with not immersive virtual reality have been used in neurological disorders rehabilitation process. Objective: To evaluate the effectiveness of the video game console Nintendo Wii (NW on postural balance and mobility treatment of adults with PD in Hoehn and Yahr stages I to III. Methods: The following databases were searched electronically on MEDLINE, Cochrane Library, PEDro, CAPES Periodic, BIREME, and LILACS databases. The search period for this review was January 2010 to June 2016. The assessment of methodological quality was performed using the PEDro Scale as reference. Results: 12 original studies were selected, but only 3 were randomized controlled trials (RCTs. Conclusion: Some of the studies analysed suggest that NW can provide improvement in balance and mobility of adults with PD. These benefits should be interpreted with caution because of the low methodological quality of the included trials, and the lack of common assessment of treatment effects. There is little evidence to ensure the effectiveness and support the inclusion of the treatment with NW of patients with PD.

Postural threat differentially affects the feedforward and feedback components of the vestibular-evoked balance response.

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Osler, Callum J; Tersteeg, M C A; Reynolds, Raymond F; Loram, Ian D

2013-10-01

Circumstances may render the consequence of falling quite severe, thus maximising the motivation to control postural sway. This commonly occurs when exposed to height and may result from the interaction of many factors, including fear, arousal, sensory information and perception. Here, we examined human vestibular-evoked balance responses during exposure to a highly threatening postural context. Nine subjects stood with eyes closed on a narrow walkway elevated 3.85 m above ground level. This evoked an altered psycho-physiological state, demonstrated by a twofold increase in skin conductance. Balance responses were then evoked by galvanic vestibular stimulation. The sway response, which comprised a whole-body lean in the direction of the edge of the walkway, was significantly and substantially attenuated after ~800 ms. This demonstrates that a strong reason to modify the balance control strategy was created and subjects were highly motivated to minimise sway. Despite this, the initial response remained unchanged. This suggests little effect on the feedforward settings of the nervous system responsible for coupling pure vestibular input to functional motor output. The much stronger, later effect can be attributed to an integration of balance-relevant sensory feedback once the body was in motion. These results demonstrate that the feedforward and feedback components of a vestibular-evoked balance response are differently affected by postural threat. Although a fear of falling has previously been linked with instability and even falling itself, our findings suggest that this relationship is not attributable to changes in the feedforward vestibular control of balance. © 2013 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

The complexity of standing postural control in older adults: a modified detrended fluctuation analysis based upon the empirical mode decomposition algorithm.

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Junhong Zhou

Full Text Available Human aging into senescence diminishes the capacity of the postural control system to adapt to the stressors of everyday life. Diminished adaptive capacity may be reflected by a loss of the fractal-like, multiscale complexity within the dynamics of standing postural sway (i.e., center-of-pressure, COP. We therefore studied the relationship between COP complexity and adaptive capacity in 22 older and 22 younger healthy adults. COP magnitude dynamics were assessed from raw data during quiet standing with eyes open and closed, and complexity was quantified with a new technique termed empirical mode decomposition embedded detrended fluctuation analysis (EMD-DFA. Adaptive capacity of the postural control system was assessed with the sharpened Romberg test. As compared to traditional DFA, EMD-DFA more accurately identified trends in COP data with intrinsic scales and produced short and long-term scaling exponents (i.e., α(Short, α(Long with greater reliability. The fractal-like properties of COP fluctuations were time-scale dependent and highly complex (i.e., α(Short values were close to one over relatively short time scales. As compared to younger adults, older adults demonstrated lower short-term COP complexity (i.e., greater α(Short values in both visual conditions (p>0.001. Closing the eyes decreased short-term COP complexity, yet this decrease was greater in older compared to younger adults (p<0.001. In older adults, those with higher short-term COP complexity exhibited better adaptive capacity as quantified by Romberg test performance (r(2 = 0.38, p<0.001. These results indicate that an age-related loss of COP complexity of magnitude series may reflect a clinically important reduction in postural control system functionality as a new biomarker.

Postural Variables in Girls Practicing Volleyball

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Grabara, Malgorzata; Hadzik, Andrzej

2009-01-01

Study aim: To assess body posture of young female volleyball players in relation to their untrained mates. Material and methods: A group of 42 volleyball players and another of 43 untrained girls, all aged 13-16 years were studied with respect to their body posture indices by using computer posturography. Spinal angles and curvatures were…

Task-related and person-related variables influence the effect of low back pain on anticipatory postural adjustments.

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Jacobs, Jesse V; Lyman, Courtney A; Hitt, Juvena R; Henry, Sharon M

2017-08-01

People with low back pain exhibit altered postural coordination that has been suggested as a target for treatment, but heterogeneous presentation has rendered it difficult to identify appropriate candidates and protocols for such treatments. This study evaluated the associations of task-related and person-related factors with the effect of low back pain on anticipatory postural adjustments. Thirteen subjects with and 13 without low back pain performed seated, rapid arm flexion in self-initiated and cued conditions. Mixed-model ANOVA were used to evaluate group and condition effects on APA onset latencies of trunk muscles, arm-raise velocity, and pre-movement cortical potentials. These measures were evaluated for correlation with pain ratings, Fear Avoidance Beliefs Questionnaire scores, and Modified Oswestry Questionnaire scores. Delayed postural adjustments of subjects with low back pain were greater in the cued condition than in the self-initiated condition. The group with low back pain exhibited larger-amplitude cortical potentials than the group without pain, but also significantly slower arm-raise velocities. With arm-raise velocity as a covariate, the effect of low back pain remained significant for the latencies of postural adjustments but not for cortical potentials. Latencies of the postural adjustments significantly correlated with Oswestry and Fear Avoidance Beliefs scores. Delayed postural adjustments with low back pain appear to be influenced by cueing of movement, pain-related disability and fear of activity. These results highlight the importance of subject characteristics, task condition, and task performance when comparing across studies or when developing treatment of people with low back pain. Copyright © 2017 Elsevier B.V. All rights reserved.

Physiological Mechanisms Mediating the Coupling between Heart Period and Arterial Pressure in Response to Postural Changes in Humans.

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Silvani, Alessandro; Calandra-Buonaura, Giovanna; Johnson, Blair D; van Helmond, Noud; Barletta, Giorgio; Cecere, Anna G; Joyner, Michael J; Cortelli, Pietro

2017-01-01

The upright posture strengthens the coupling between heart period (HP) and systolic arterial pressure (SAP) consistently with a greater contribution of the arterial baroreflex to cardiac control, while paradoxically decreasing cardiac baroreflex sensitivity (cBRS). To investigate the physiological mechanisms that mediate the coupling between HP and SAP in response to different postures, we analyzed the cross-correlation functions between low-frequency HP and SAP fluctuations and estimated cBRS with the sequence technique in healthy male subjects during passive head-up tilt test (HUTT, n = 58), during supine wakefulness, supine slow-wave sleep (SWS), and in the seated and active standing positions ( n = 8), and during progressive loss of 1 L blood ( n = 8) to decrease central venous pressure in the supine position. HUTT, SWS, the seated, and the standing positions, but not blood loss, entailed significant increases in the positive correlation between HP and the previous SAP values, which is the expected result of arterial baroreflex control, compared with baseline recordings in the supine position during wakefulness. These increases were mirrored by increases in the low-frequency variability of SAP in each condition but SWS. cBRS decreased significantly during HUTT, in the seated and standing positions, and after blood loss compared with baseline during wakefulness. These decreases were mirrored by decreases in the RMSSD index, which reflects cardiac vagal modulation. These results support the view that the cBRS decrease associated with the upright posture is a byproduct of decreased cardiac vagal modulation, triggered by the arterial baroreflex in response to central hypovolemia. Conversely, the greater baroreflex contribution to cardiac control associated with upright posture may be explained, at least in part, by enhanced fluctuations of SAP, which elicit a more effective entrainment of HP fluctuations by the arterial baroreflex. These SAP fluctuations may result

Postural changes in dental hygienists. Four-year longitudinal study.

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Barry, R M; Woodall, W R; Mahan, J M

1992-01-01

Numerous surveys identify the occurrence of musculoskeletal complaints as a concern in dentistry. However, no longitudinal data exist to indicate whether postural changes occur as a result of practicing dental hygiene. The purpose of this preliminary, four-year longitudinal study was to investigate whether any postural changes developed during the hygienists' clinical education and/or during subsequent dental hygiene practice after one and/or two years. It was anticipated that the awkward positions and intense physical demands placed on hygienists might initiate musculoskeletal problems, but that no postural changes would occur over this short period of time. Nine of 10 dental hygienists in the graduating class of 1987 were surveyed for existing musculoskeletal complaints, and the subjects were photographed for a measurement of postural change. Responses from participants indicated an increase in musculoskeletal-related complaints in each of the six areas investigated. The photographic findings indicated that one of the nine hygienists showed an increase in forward head posture, a postural change.

Barnacle geese achieve significant energetic savings by changing posture.

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Tickle, Peter G; Nudds, Robert L; Codd, Jonathan R

2012-01-01

Here we report the resting metabolic rate in barnacle geese (Branta leucopsis) and provide evidence for the significant energetic effect of posture. Under laboratory conditions flow-through respirometry together with synchronous recording of behaviour enabled a calculation of how metabolic rate varies with posture. Our principal finding is that standing bipedally incurs a 25% increase in metabolic rate compared to birds sitting on the ground. In addition to the expected decrease in energy consumption of hindlimb postural muscles when sitting, we hypothesise that a change in breathing mechanics represents one potential mechanism for at least part of the observed difference in energetic cost. Due to the significant effect of posture, future studies of resting metabolic rates need to take into account and/or report differences in posture.

THE PRESENCE OF POSTURAL DEFORMITIES OF THE YOUTH DEPENDING ON THE LEVEL OF PARENTS KNOWLADGE ABOUT DEFICIENT BODY POSTURE

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Zoran Bogdanović

2007-05-01

Full Text Available The subject of this study is deterimining the presence of postural deformities in sagittal view (defi cient kyphotic and lordotic body posture of the youth depanding on the level of parents knowladge about defi cient body posture. The complete content of the program was conducted in the territory of the city of Kragujevac in several elementary schools, comprising 299 students of the 5th grade and their parents. The object of this study was to determine the number of students with defi cient kyphotic and lordotic body posture, to determine the presence of dis arrangements depanding on the gender and to determine the presence of kyphotic and lordotic deformity depanding on the parents level of information about defi ciant body posture among children. Kyphotic deformity of the examiners of male population is mostly present in the group of parents who are poorly informed about body posture defi ciency. Regarding examiners of female population , the presence of deformation is equally divided on the group of parents who expressed themselves as being very well, those who are undecided and those who are poorly informed. The more signifi cant presence of kyphotic deformity is at examiners of male population than at the examiners of female population while the higher presence of lordotic deformity is at the examiners of female population. Regarding female population we can observe the highest presence of deformation in the group of parents who are undecided while the other groups are very equabal by the presence of deformation. Stated measures impose a statement that it is necessary to continuosly work on both - children education and parents education aiming to recognize posture defi ciency and physical deformation of school and preschool population and all of this with the object of reducing the deformation and on time detecting certain disarrangements and taking adaquate measures for its senctuary

Resonant Drag Instabilities in protoplanetary disks: the streaming instability and new, faster-growing instabilities

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Squire, Jonathan; Hopkins, Philip F.

2018-04-01

We identify and study a number of new, rapidly growing instabilities of dust grains in protoplanetary disks, which may be important for planetesimal formation. The study is based on the recognition that dust-gas mixtures are generically unstable to a Resonant Drag Instability (RDI), whenever the gas, absent dust, supports undamped linear modes. We show that the "streaming instability" is an RDI associated with epicyclic oscillations; this provides simple interpretations for its mechanisms and accurate analytic expressions for its growth rates and fastest-growing wavelengths. We extend this analysis to more general dust streaming motions and other waves, including buoyancy and magnetohydrodynamic oscillations, finding various new instabilities. Most importantly, we identify the disk "settling instability," which occurs as dust settles vertically into the midplane of a rotating disk. For small grains, this instability grows many orders of magnitude faster than the standard streaming instability, with a growth rate that is independent of grain size. Growth timescales for realistic dust-to-gas ratios are comparable to the disk orbital period, and the characteristic wavelengths are more than an order of magnitude larger than the streaming instability (allowing the instability to concentrate larger masses). This suggests that in the process of settling, dust will band into rings then filaments or clumps, potentially seeding dust traps, high-metallicity regions that in turn seed the streaming instability, or even overdensities that coagulate or directly collapse to planetesimals.

Effects of posture on postoperative pulmonary function

DEFF Research Database (Denmark)

Nielsen, K G; Holte, Kathrine; Kehlet, H

2003-01-01

BACKGROUND: Pulmonary morbidity is still a relevant complication to major surgery despite improvements in surgical technique and anaesthetic methods. Postoperative posture may be a pathogenic factor, but the effects of changes in postoperative posture on pulmonary function have not been reviewed...

Multisensory training for postural sway control in non-injured elderly ...

African Journals Online (AJOL)

Multisensory training for postural sway control in non-injured elderly females. ... Elderly adults demonstrate increased postural sway, which may ultimately lead to falls. ... Keywords: multisensory training, postural sway control, balance ability, ...

Development of the Coordination between Posture and Manual Control

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Haddad, Jeffrey M.; Claxton, Laura J.; Keen, Rachel; Berthier, Neil E.; Riccio, Gary E.; Hamill, Joseph; Van Emmerik, Richard E. A.

2012-01-01

Studies have suggested that proper postural control is essential for the development of reaching. However, little research has examined the development of the coordination between posture and manual control throughout childhood. We investigated the coordination between posture and manual control in children (7- and 10-year-olds) and adults during…

Cerebellar transcranial direct current stimulation improves adaptive postural control.

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Poortvliet, Peter; Hsieh, Billie; Cresswell, Andrew; Au, Jacky; Meinzer, Marcus

2018-01-01

Rehabilitation interventions contribute to recovery of impaired postural control, but it remains a priority to optimize their effectiveness. A promising strategy may involve transcranial direct current stimulation (tDCS) of brain areas involved in fine-tuning of motor adaptation. This study explored the effects of cerebellar tDCS (ctDCS) on postural recovery from disturbance by Achilles tendon vibration. Twenty-eight healthy volunteers participated in this sham-ctDCS controlled study. Standing blindfolded on a force platform, four trials were completed: 60 s quiet standing followed by 20 min active (anodal-tDCS, 1 mA, 20 min, N = 14) or sham-ctDCS (40 s, N = 14) tDCS; three quiet standing trials with 15 s of Achilles tendon vibration and 25 s of postural recovery. Postural steadiness was quantified as displacement, standard deviation and path derived from the center of pressure (COP). Baseline demographics and quiet standing postural steadiness, and backwards displacement during vibration were comparable between groups. However, active-tDCS significantly improved postural steadiness during vibration and reduced forward displacement and variability in COP derivatives during recovery. We demonstrate that ctDCS results in short-term improvement of postural adaptation in healthy individuals. Future studies need to investigate if multisession ctDCS combined with training or rehabilitation interventions can induce prolonged improvement of postural balance. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

Effects of 30-, 60-, and 90-Day Bed Rest on Postural Control in Men and Women

Science.gov (United States)

Esteves, Julie; Taylor, Laura C.; Vanya, Robert D.; Dean, S. Lance; Wood, Scott J.

2011-01-01

INTRODUCTION Head-down-tilt bed rest (HDT) has been used as a safe gr ound-based analog to mimic and develop countermeasures for the physiological effects of spaceflight, including decrements in postural stability. The purpose of this investigation was to characterize the effects of 30-, 60-, and 90-day bed rest on postural control in men and women. METHODS Twenty-nine subjects (18M,11F) underwent 13 days of ambula tory acclimatization and were placed in 6? HDT for 30 (n=12), 60 (n=8), or 90 (n=9) days, followed by 14 days of ambulatory recovery. Computerized dynamic posturography (CDP) was used to assess changes in sensory and motor components of postural control, and recovery after HDT. Sensory Organization Tests (SOTs) objectively evaluate one?s ability to effectively use or suppress visual, vestibular, and proprioceptive information for postural control. Stability during the SOTs was assessed using peak-to-peak sway and convergence toward stability limits to derive an equilibrium score. Motor Control Tests (MCTs) evaluate one?s ability to recover from unexpected support surface perturbations, with performance determined by center-of-pressure path length. Whole-body kinematic data were collected to determine body-sway strategy used to maintain stability during each condition. Baselines were determined pre-HDT. Recovery was tracked post-HDT on days 0, 1, 2, and 4. RESULTS Immediately after HDT, subjects showed decreased performance on most SOTs, primarily on sway-referenced support conditions, typically returning to baseline levels within 4 days. MCT performance was not significantly affected. There were no significant gender or duration differences in performance. Kinematic data revealed a tendency to use ankle strategy to maintain an upright stance during most SOT conditions. Interestingly, six subjects (2M,4F) experienced orthostatic intolerance and were unable to complete day 0 testing. CONCLUSION HDT mimics some un loading mechanisms of spaceflight and

Earth's core formation due to the Rayleigh-Taylor instability

International Nuclear Information System (INIS)

Ida, S.; Nakagawa, Y.; Nakazawa, K.

1987-01-01

A protoearth accretion stage configuration consisting of an undifferentiated solid core, an intermediate metal-melt layer, and an outer silicate-melt layer, is presently taken as the initial state in an investigation of Rayleigh-Taylor instability-induced core formation. The Ida et al. (to be published) quantitative results on the instability in a self-gravitating fluid sphere are used. The instability is found to occur through the translational mode on a time-scale of about 10 hr, in the case where the metal-melt layer is greater than about 1 km; this implies that the earth's core formed due to the undifferentiated solid core's translation upon the outer layer's melting. Differentiation would then have occurred in the late accretion stage. 17 references

Postural habits of young adults and possibilities of modification.

Science.gov (United States)

Nowotny-Czupryna, Olga; Czupryna, Krzysztof; Bąk, Krzysztof; Wróblewska, Ewa; Rottermund, Jerzy

2013-01-01

The aim of the study was to assess postural habits in young, healthy people, identify correlations between postural errors and pain and attempt to modify bad habits. 144 people, aged 18-23 were enrolled. The intervention consisted of 4 stages: Stage 1 - identification of postural habits, description of responses to stress, back pain frequency and intensity (Jackson & Moskowitz); Stage 2 - correction of habitual position with the help of a physiotherapist, briefing about ergonomic everyday behaviours and consequences of continued non-ergonomic behaviours, Stage 3 - follow-up examination: self-assessment of changes, evaluation of the effects of modifications, determination of causes for discontinuing the behaviour modification programme, where applicable; and Stage 4 - final examination, assessment of results. Correlations were sought between inappropriate postural behaviour in various positions and between non-ergonomic postural behaviour and pain location and response to stress. Statistical analysis was carried out with Excel and Statistica v. 7.1. A non-parametric χ(2) test was used at phabit. 3. An attempt to modify non-ergonomic postural behaviours usually results in pain, which may act as a demotivating factor. 4. Discomfort associated with the modification of habitual postural behaviours is reduced after 3-4 months of regular training.

The influence of computer use on the sitting posture of high school students who develop neck and shoulder pain

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Y. Brink

2009-02-01

Full Text Available The prevalence of neck and shoulder pain (NSP is increas-ing in adolescents and is related to increased time spent on computers.The influence of sitting posture on the development of computer-relatedNSP among adolescents is unclear. This study investigated how the sittingposture of the upper quadrant changes over a ten minute period ofcomputer use in once asymptomatic adolescents who later developed NSP.M ethod: Sitting alignment was measured using the Photographic PostureA nalysis Method. The students performed a typing task while two con -secutive photographs were taken ten minutes apart. The students werefollowed for six months and the photographs of those who developed NSPw ere analy z ed.R esults: The results show that there is no significant change in sitting posture over time. Observationally the most common pattern was to move from a more flexed posture to a more upright posture and there were greater posturalchanges in the case group (students with extreme cervical angles compared to the control group (students with thepreferred cervical ROM (34.75º - 43.95º, although both findings were not statistically significant.Conclusion: There was no change, over a ten minute period, in the sitting posture of computing high school studentswho developed computer-related NSP after six months therefore students should be encouraged to avoid monotonoussitting in front of computers because this could be associated with NSP.

Postural stability in young and old women

DEFF Research Database (Denmark)

Jørgensen, Martin Grønbech

at an early stage, good knowledge and sensitive measurements of postural stability are essential. In addition, in order to develop effective intervention strategies such knowledge is of major importance. However, no single postural stability parameter has effectively been able to identify individuals at risk...... of falling. Hence, there is a strong need for development and identification of sensitive postural sway parameters in various demographic groups. The aim of this study was to explore differences in postural stability between physically active old (O) and young (Y) women using newly developed sway parameters....... METHODS AND MATERIALS: Center of pressure (CoP) excursion was measured (100 Hz) by force plate (AMTI) analysis in old (72.5±6.3 years) and young (25.8±1.6 years) women during static 2-leg (bilateral) and 1-leg (unilateral) standing (15-s) with eyes opened. RESULTS: O demonstrated elevated CoP sway length...

Classifying Transition Behaviour in Postural Activity Monitoring

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James BRUSEY

2009-10-01

Full Text Available A few accelerometers positioned on different parts of the body can be used to accurately classify steady state behaviour, such as walking, running, or sitting. Such systems are usually built using supervised learning approaches. Transitions between postures are, however, difficult to deal with using posture classification systems proposed to date, since there is no label set for intermediary postures and also the exact point at which the transition occurs can sometimes be hard to pinpoint. The usual bypass when using supervised learning to train such systems is to discard a section of the dataset around each transition. This leads to poorer classification performance when the systems are deployed out of the laboratory and used on-line, particularly if the regimes monitored involve fast paced activity changes. Time-based filtering that takes advantage of sequential patterns is a potential mechanism to improve posture classification accuracy in such real-life applications. Also, such filtering should reduce the number of event messages needed to be sent across a wireless network to track posture remotely, hence extending the system’s life. To support time-based filtering, understanding transitions, which are the major event generators in a classification system, is a key. This work examines three approaches to post-process the output of a posture classifier using time-based filtering: a naïve voting scheme, an exponentially weighted voting scheme, and a Bayes filter. Best performance is obtained from the exponentially weighted voting scheme although it is suspected that a more sophisticated treatment of the Bayes filter might yield better results.

Barnacle geese achieve significant energetic savings by changing posture.

Directory of Open Access Journals (Sweden)

Peter G Tickle

Full Text Available Here we report the resting metabolic rate in barnacle geese (Branta leucopsis and provide evidence for the significant energetic effect of posture. Under laboratory conditions flow-through respirometry together with synchronous recording of behaviour enabled a calculation of how metabolic rate varies with posture. Our principal finding is that standing bipedally incurs a 25% increase in metabolic rate compared to birds sitting on the ground. In addition to the expected decrease in energy consumption of hindlimb postural muscles when sitting, we hypothesise that a change in breathing mechanics represents one potential mechanism for at least part of the observed difference in energetic cost. Due to the significant effect of posture, future studies of resting metabolic rates need to take into account and/or report differences in posture.

Electromyographic activity of the trunk extensor muscles: effect of varying hip position and lumbar posture during Roman chair exercise.

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Mayer, John M; Verna, Joe L; Manini, Todd M; Mooney, Vert; Graves, James E

2002-11-01

To evaluate the effect of hip position and lumbar posture on the surface electromyographic activity of the trunk extensors during Roman chair exercise. Descriptive, repeated measures. University-based musculoskeletal research laboratory. Twelve healthy volunteers (7 men, 5 women; age range, 18-35y) without a history of low back pain were recruited from a university setting. Not applicable. Surface electromyographic activity was recorded from the lumbar extensor, gluteal, and hamstring musculature during dynamic Roman chair exercise. For each muscle group, electromyographic activity (mV/rep) was compared among exercises with internal hip rotation and external hip rotation and among exercises by using a typical lumbar posture (nonbiphasic) and a posture that accentuated lumbar lordosis (biphasic). For the lumbar extensors, electromyographic activity during exercise was 18% greater with internal hip rotation than external hip rotation (Phamstrings, there was no difference in electromyographic activity between internal and external hip rotation or between biphasic and nonbiphasic postures (P >.05). The level of recruitment of the lumbar extensors can be modified during Roman chair exercise by altering hip position and lumbar posture. Clinicians can use these data to develop progressive exercise protocols for the lumbar extensors with a variety of resistance levels without the need for complex equipment. Copyright 2002 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation

Chronicle of ion-current instabilities: old and new

International Nuclear Information System (INIS)

Landau, R.W.

1975-07-01

For counter-streaming ion currents along a uniform magnetic field, a purely growing instability exists with a growth rate as high as 16 times the ion gyrofrequency. When the streaming ions are only 1 percent of the stationary ions, the growth rate is still 4 times the gyrofrequency, but the real part is near the lower hybrid frequency. These instabilities are in addition to the Drummond-Rosenbluth ion mode. Finite β effects increase the growth rate and can be important for β greater than 10 -4 . In all this, T/sub parallel,+/ = T/sub parallel,-/ and T/sub perpendicular to/ = 0. (U.S.)

Qualitative postural analysis among boys and girls of seven to ten years of age Análise postural qualitativa entre meninos e meninas de sete a dez anos de idade

Directory of Open Access Journals (Sweden)

PJ Penha

2008-10-01

Full Text Available BACKGROUND: Postural abnormalities are often found in children. At this stage of life, posture undergoes many adjustments and adaptations due to body changes. Objective: To qualitatively identify the postural abnormalities which occur most frequently among children aged OBJECTIVE: Reven and ten years, comparing boys and girls, and to evaluate these subjects' lumbar flexibility. METHODS: One hundred and ninety-one children were photographed in the sagittal and frontal planes. The variables analyzed were: ankle (valgus and varus, tibiotarsal angle (opened and closed, knee (hyperextension and semiflexion, valgus and varus, pelvis (anteversion and retroversion; lateral pelvic inclination, trunk (antepulsion and retropulsion, lumbar spine (hyperlordosis and rectification, thoracic spine (hyperkyphosis and rectification, cervical spine (hyperlordosis and rectification, scoliosis, shoulder (imbalance and protraction, scapula (winged, abducted and adducted and head (tilt and protraction. The lumbar flexibility was assessed using Schöber's index. RESULTS: The boys had greater incidence of winged scapula, shoulder imbalance, protraction of shoulders and head and cervical hyperlordosis than the girls did. Conversely, the girls had greater incidence of head tilt and larger Schöber index values. CONCLUSIONS: There were abnormalities in children's postural development that are probably related to muscle, skeletal and flexibility differences between the genders. These differences may influence each child's postural pattern during growth.CONTEXTUALIZAÇÃO: Alterações posturais são freqüentemente encontradas em crianças. Nessa fase, a postura sofre uma série de ajustes e adaptações às mudanças no próprio corpo. OBJETIVO: Identificar, de maneira qualitativa, quais as alterações posturais mais freqüentes em crianças entre sete e dez anos, comparando meninos e meninas, e avaliar a flexibilidade lombar desses sujeitos. MATERIAIS E MÉTODOS: Cento e

The relationship between the stomatognathic system and body posture

Directory of Open Access Journals (Sweden)

Antonino Cuccia

2009-01-01

Full Text Available In recent years, many researchers have investigated the various factors that can influence body posture: mood states, anxiety, head and neck positions, oral functions (respiration, swallowing, oculomotor and visual systems, and the inner ear. Recent studies indicate a role for trigeminal afferents on body posture, but this has not yet been demonstrated conclusively. The present study aims to review the papers that have shown a relationship between the stomatognathic system and body posture. These studies suggest that tension in the stomatognathic system can contribute to impaired neural control of posture. Numerous anatomical connections between the stomatognathic system's proprioceptive inputs and nervous structures are implicated in posture (cerebellum, vestibular and oculomotor nuclei, superior colliculus. If the proprioceptive information of the stomatognathic system is inaccurate, then head control and body position may be affected. In addition, the present review discusses the role the myofascial system plays in posture. If confirmed by further research, these considerations can improve our understanding and treatment of muscular-skeletal disorders that are associated with temporomandibular joint disorders, occlusal changes, and tooth loss.

The Relationship Between the Stomatognathic System and Body Posture

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Cuccia, Antonino; Caradonna, Carola

2009-01-01

In recent years, many researchers have investigated the various factors that can influence body posture: mood states, anxiety, head and neck positions, oral functions (respiration, swallowing), oculomotor and visual systems, and the inner ear. Recent studies indicate a role for trigeminal afferents on body posture, but this has not yet been demonstrated conclusively. The present study aims to review the papers that have shown a relationship between the stomatognathic system and body posture. These studies suggest that tension in the stomatognathic system can contribute to impaired neural control of posture. Numerous anatomical connections between the stomatognathic system’s proprioceptive inputs and nervous structures are implicated in posture (cerebellum, vestibular and oculomotor nuclei, superior colliculus). If the proprioceptive information of the stomatognathic system is inaccurate, then head control and body position may be affected. In addition, the present review discusses the role the myofascial system plays in posture. If confirmed by further research, these considerations can improve our understanding and treatment of muscular-skeletal disorders that are associated with temporomandibular joint disorders, occlusal changes, and tooth loss. PMID:19142553

Otolith and Vertical Canal Contributions to Dynamic Postural Control

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Black, F. Owen

1999-01-01

The objective of this project is to determine: 1) how do normal subjects adjust postural movements in response to changing or altered otolith input, for example, due to aging? and 2) how do patients adapt postural control after altered unilateral or bilateral vestibular sensory inputs such as ablative inner ear surgery or ototoxicity, respectively? The following hypotheses are under investigation: 1) selective alteration of otolith input or abnormalities of otolith receptor function will result in distinctive spatial, frequency, and temporal patterns of head movements and body postural sway dynamics. 2) subjects with reduced, altered, or absent vertical semicircular canal receptor sensitivity but normal otolith receptor function or vice versa, should show predictable alterations of body and head movement strategies essential for the control of postural sway and movement. The effect of altered postural movement control upon compensation and/or adaptation will be determined. These experiments provide data for the development of computational models of postural control in normals, vestibular deficient subjects and normal humans exposed to unusual force environments, including orbital space flight.

A comparison of three observational techniques for assessing postural loads in industry.

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Kee, Dohyung; Karwowski, Waldemar

2007-01-01

This study aims to compare 3 observational techniques for assessing postural load, namely, OWAS, RULA, and REBA. The comparison was based on the evaluation results generated by the classification techniques using 301 working postures. All postures were sampled from the iron and steel, electronics, automotive, and chemical industries, and a general hospital. While only about 21% of the 301 postures were classified at the action category/level 3 or 4 by both OWAS and REBA, about 56% of the postures were classified into action level 3 or 4 by RULA. The inter-method reliability for postural load category between OWAS and RULA was just 29.2%, and the reliability between RULA and REBA was 48.2%. These results showed that compared to RULA, OWAS, and REBA generally underestimated postural loads for the analyzed postures, irrespective of industry, work type, and whether or not the body postures were in a balanced state.

Holding a handle for balance during continuous postural perturbations – immediate and transitionary effects on whole body posture

Directory of Open Access Journals (Sweden)

Jernej Camernik

2016-09-01

Full Text Available When balance is exposed to perturbations, hand contacts are often used to assist postural control. We investigated the immediate and the transitionary effects of supportive hand contacts during continuous anteroposterior perturbations of stance by automated waist-pulls. Ten young adults were perturbed for five minutes and required to maintain balance by holding to a stationary, shoulder-high handle and following its removal. Centre of pressure (COP displacement, hip, knee, and ankle angles, leg and trunk muscle activity and handle contact forces were acquired. The analysis of results show that COP excursions are significantly smaller when the subjects utilize supportive hand contact and that the displacement of COP is strongly correlated to the perturbation force and significantly larger in the anterior than posterior direction. Regression analysis of hand forces revealed that subjects utilized the hand support significantly more during the posterior than anterior perturbations. Moreover, kinematical analysis showed that utilization of supportive hand contacts alters posture of the whole body and that postural readjustments after the release of the handle occur at different time scales in the hip, knee, and ankle joints. Overall, our findings show that supportive hand contacts are efficiently used for balance control during continuous postural perturbations and that utilization of a handle has significant immediate and transitionary effects on whole body posture.

Variation in posture quality across musical instruments and its impact during performances.

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Blanco-Piñeiro, Patricia; Díaz-Pereira, M Pino; Martínez Vidal, Aurora

2018-06-01

Bad posture increases the risk that a musician may suffer from musculoskeletal disorders. This study compared posture quality required by different instruments or families of instruments. Using an ad-hoc postural observation instrument embracing 11 postural variables, four experts evaluated the postures of 100 students attending a Spanish higher conservatory of music. The agreement of the experts' evaluations was statistically confirmed by a Cohen's κ value between 0.855 and 1.000 and a Kendall value between 0.709 and 1.000 (p instrument families and seated posture with respect to pelvic attitude, dorsal curvature and head alignment in both sagittal and frontal planes. This analysis also showed an association between instrument families and standing posture with respect to the frontal plane of the axis of gravity, pelvic attitude, head alignment in the frontal plane, the sagittal plane of the shoulders and overall posture. While certain postural defects appear to be common to all families of instruments, others are more characteristic of some families than others. The instrument associated with the best posture quality was the bagpipe, followed by percussion and strings.

Vestibular and Somatosensory Covergence in Postural Equilibrium Control: Insights from Spaceflight and Bed Rest Studies

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Mulavara, A. P.; Batson, C. D.; Buxton, R. E.; Feiveson, A. H.; Kofman, I. S.; Lee, S. M. C.; Miller, C. A.; Peters, B. T.; Phillips, T.; Platts, S. H.;

Postural stability in a population of dancers, healthy non-dancers, and vestibular neuritis patients.

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Martin-Sanz, Eduardo; Ortega Crespo, Isabel; Esteban-Sanchez, Jonathan; Sanz, Ricardo

2017-09-01

Several studies have indicated better balance control in dancers than in control participants, but some controversy remains. The aim of our study is to evaluate the postural stability in a cohort of dancers, non-dancers, compensated, and non-compensated unilateral vestibular neuritis (VN). This is a prospective study of control subjects, dancers, and VN patients between June 2009 and December 2015. Dancers from the Dance Conservatory of Madrid and VN patients were referred to our department for analysis. After the clinical history, neuro-otological examination, audiogram, and caloric tests, the diagnosis was done. Results from clinical examination were used for the categorization of compensation situation. A computerized dynamic posturography was performed to every subject. Forty dancers and 38 women formed both 'dancer' and 'normal' cohorts. Forty-two compensated and 39 uncompensated patients formed both 'compensated' and 'uncompensated' cohorts. Dancers had significantly greater antero-posterior (AP) body sway than controls during condition 5 and 6 in the Sensory Organization Test (SOT) (p body sway in every SOT studied condition (p body say in SOT 5 and 6, showed greater values in compensated patients than the control group, the mean analysis did not show any statistical difference between the compensated and dancer groups, in such SOT conditions. Dancers demonstrated greater sways than non-dancers when they relied their postural control on vestibular input alone. Compensated patients had a similar posturographic pattern that the dancers cohort, suggesting a similar shift from visual to somatosensory information.

The relationship between sitting posture and seated-related upper quadrant musculoskeletal pain in computing South African adolescents: A prospective study.

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Brink, Yolandi; Louw, Quinette; Grimmer, Karen; Jordaan, Esmè

2015-12-01

There is evidence that consistent sitting for prolonged periods is associated with upper quadrant musculoskeletal pain (UQMP). It is unclear whether postural alignment is a significant risk factor. The aim of the prospective study (2010-2011) was to ascertain if three-dimensional sitting postural angles, measured in a real-life school computer classroom setting, predict seated-related UQMP. Asymptomatic Grade 10 high-school students, aged 15-17 years, undertaking Computer Application Technology, were eligible to participate. Using the 3D Posture Analysis Tool, sitting posture was measured while students used desk-top computers. Posture was reported as five upper quadrant angles (Head flexion, Neck flexion; Craniocervical angle, Trunk flexion and Head lateral bending). The Computer Usage Questionnaire measured seated-related UQMP and hours of computer use. The Beck Depression Inventory and the Multidimensional Anxiety Scale for Children assessed psychosocial factors. Sitting posture, computer use and psychosocial factors were measured at baseline. UQMP was measured at six months and one-year follow-up. 211, 190 and 153 students participated at baseline, six months and one-year follow-up respectively. 34.2% students complained of seated-related UQMP during the follow-up period. Increased head flexion (HF) predicted seated-related UQMP developing over time for a small group of students with pain scores greater than the 90th pain percentile, adjusted for age, gender, BMI, computer use and psychosocial factors (p = 0.003). The pain score increased 0.22 points per 1° increase in HF. Classroom ergonomics and postural hygiene should therefore focus on reducing large HF angles among computing adolescents. Copyright © 2015 Elsevier Ltd. All rights reserved.

Recognition of dance-like actions: memory for static posture or dynamic movement?

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Vicary, Staci A; Robbins, Rachel A; Calvo-Merino, Beatriz; Stevens, Catherine J

2014-07-01

Dance-like actions are complex visual stimuli involving multiple changes in body posture across time and space. Visual perception research has demonstrated a difference between the processing of dynamic body movement and the processing of static body posture. Yet, it is unclear whether this processing dissociation continues during the retention of body movement and body form in visual working memory (VWM). When observing a dance-like action, it is likely that static snapshot images of body posture will be retained alongside dynamic images of the complete motion. Therefore, we hypothesized that, as in perception, posture and movement would differ in VWM. Additionally, if body posture and body movement are separable in VWM, as form- and motion-based items, respectively, then differential interference from intervening form and motion tasks should occur during recognition. In two experiments, we examined these hypotheses. In Experiment 1, the recognition of postures and movements was tested in conditions in which the formats of the study and test stimuli matched (movement-study to movement-test, posture-study to posture-test) or mismatched (movement-study to posture-test, posture-study to movement-test). In Experiment 2, the recognition of postures and movements was compared after intervening form and motion tasks. These results indicated that (1) the recognition of body movement based only on posture is possible, but it is significantly poorer than recognition based on the entire movement stimulus, and (2) form-based interference does not impair memory for movements, although motion-based interference does. We concluded that, whereas static posture information is encoded during the observation of dance-like actions, body movement and body posture differ in VWM.

Impact of Computer Related Posture on the Occurrence of Musculoskeletal Discomfort among Secondary School Students in Lagos, Nigeria.

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Odebiyi, D O; Olawale, O A; Adeniji, Y M

2013-01-01

Computers have become an essential part of life particularly in industrially advanced countries of the world. Children now have greater accessibility to computers both at school and at home. Recent studies suggest that with this increased exposure, there are associated musculoskeletal disorders (MSDs) in both school-aged children and adults. To assess the posture assumed by secondary school students during computer use and its impact on the occurrence and severity of reported musculoskeletal discomforts. Posture assumed during normal computer class, occurrence of discomforts, body parts involved and the intensity of discomforts were evaluated in 235 school aged children using Rapid Upper Limb Assessment (RULA) scale, Body Discomfort Chart (BDC) and Visual Analogue Scale (VAS) before and after normal computer class. Inferential statistics of t-test and chi-square were used to determine significance difference between variables, with level of significant set at p Computer use produced significant discomforts on the neck, shoulder and low back. There was a significant relationship between participants height and posture assumed. Two hundred and eleven (89.8%) participants reported discomforts/pain during the use of computer. Weight and height were contributory factors to the occurrence of musculoskeletal discomfort/pain (p computer use. Weight and height were implicated as factors that influenced the form of posture and the nature of the reported discomfort. Creating awareness about the knowledge of ergonomics and safety for promotion of good posture was therefore recommended.

Quantifying the effect of intervertebral cartilage on neutral posture in the necks of sauropod dinosaurs

Directory of Open Access Journals (Sweden)

Michael P. Taylor

2014-12-01

Full Text Available Attempts to reconstruct the neutral neck posture of sauropod dinosaurs, or indeed any tetrapod, are doomed to failure when based only on the geometry of the bony cervical vertebrae. The thickness of the articular cartilage between the centra of adjacent vertebrae affects posture. It extends (raises the neck by an amount roughly proportional to the thickness of the cartilage. It is possible to quantify the angle of extension at an intervertebral joint: it is roughly equal, in radians, to the cartilage thickness divided by the height of the zygapophyseal facets over the centre of rotation. Applying this formula to published measurements of well-known sauropod specimens suggests that if the thickness of cartilage were equal to 4.5%, 10% or 18% of centrum length, the neutral pose of the Apatosaurus louisae holotype CM 3018 would be extended by an average of 5.5, 11.8 or 21.2 degrees, respectively, at each intervertebral joint. For the Diplodocus carnegii holotype CM 84, the corresponding angles of additional extension are even greater: 8.4, 18.6 or 33.3 degrees. The cartilaginous neutral postures (CNPs calculated for 10% cartilage—the most reasonable estimate—appear outlandish. But it must be remembered that these would not have been the habitual life postures, because tetrapods habitually extend the base of their neck and flex the anterior part, yielding the distinctive S-curve most easily seen in birds.

Quantifying the effect of intervertebral cartilage on neutral posture in the necks of sauropod dinosaurs.

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Taylor, Michael P

2014-01-01

Attempts to reconstruct the neutral neck posture of sauropod dinosaurs, or indeed any tetrapod, are doomed to failure when based only on the geometry of the bony cervical vertebrae. The thickness of the articular cartilage between the centra of adjacent vertebrae affects posture. It extends (raises) the neck by an amount roughly proportional to the thickness of the cartilage. It is possible to quantify the angle of extension at an intervertebral joint: it is roughly equal, in radians, to the cartilage thickness divided by the height of the zygapophyseal facets over the centre of rotation. Applying this formula to published measurements of well-known sauropod specimens suggests that if the thickness of cartilage were equal to 4.5%, 10% or 18% of centrum length, the neutral pose of the Apatosaurus louisae holotype CM 3018 would be extended by an average of 5.5, 11.8 or 21.2 degrees, respectively, at each intervertebral joint. For the Diplodocus carnegii holotype CM 84, the corresponding angles of additional extension are even greater: 8.4, 18.6 or 33.3 degrees. The cartilaginous neutral postures (CNPs) calculated for 10% cartilage-the most reasonable estimate-appear outlandish. But it must be remembered that these would not have been the habitual life postures, because tetrapods habitually extend the base of their neck and flex the anterior part, yielding the distinctive S-curve most easily seen in birds.

[Occlusion and posture: is there evidence of correlation?].

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Michelotti, A; Manzo, P; Farella, M; Martina, R

1999-11-01

The observation that the masticatory system and the postural body regulating system are anatomically and functionally related, has led to postulate several hypotheses of correlation between occlusal and postural disturbances. In the last decade, these arguments have gained a great social impact, also because they have been broadly spread by the mass-media. As a consequence, there has been a growing number of patients seeking concomitant occlusal and postural treatments. The aim of this study was to review critically the current evidence of correlation between the two systems; this in order to address clinical issues for the management of patients. Methodology of the studies reviewed has been evaluated according to the criteria suggested by Storey and Rugh 20 rif. Although there are some evidences of correlation between occlusion and posture, this appears limited to the cranio-cervical tract of the column and tends to disappear when descending in cranio-caudal direction. On the basis of this review of the literature, it's not advisable to treat postural imbalance by means of occlusal treatment or vice versa, particularly if the therapeutic modalities are irreversible.

Screening initial entry training trainees for postural faults and low back or hip pain.

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Lane, John R

2014-01-01

The frequency of postural faults and postural awareness in military trainees has not been assessed. Five hundred Soldiers entering Advanced Individual Training were screened for standing posture and completed an anonymous questionnaire during inprocessing. Postural faults were identified in 202 subjects. Chi square analysis demonstrated a relationship between posture observed and posture reported: 87% of subjects with postural faults were unaware of postural faults; 12% with proper posture reported having poor posture. Subjects reported comparable frequencies of back pain and hip pain with postural faults (33.2%, 21.2%) and without faults (28.5%, 14.7%). Anonymous reporting was higher than formal reporting and requests for care during the same period (37% vs 3.4%).

Accessing hospital packaged foods and beverages: the importance of a seated posture when eating.

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Bell, A; Tapsell, L; Walton, K; Yoxall, A

2017-06-01

Hospitalised and community dwelling older people (aged 65 years and over) have difficulties opening certain food and beverage items (e.g. cheese portions and tetra packs) served in public hospitals. Previously, the role of hand strength on successful pack opening has been explored in a seated position. However, because many people in hospital eat in bed, the present laboratory study examined the differences between participants opening a selection of products in a hospital bed and a chair. The present study used a qualitative method (satisfaction) and quantitative methods (grip and pinch strength, dexterity, time and attempts) in two conditions (bed; chair) in a sample of well older community dwelling adults (n = 34). Packs tested included foil sealed thickened pudding, foil sealed thickened water, tetra pack, dessert, custard, jam, cereal, honey sachet and cheese portions. Honey sachets, cheese portions, foil sealed thickened pudding and tetra packs were the most difficult packs to open, with 15% of cheese portions unable to be opened in either the bed or chair posture. Although grip strength was consistent for each posture, pinch grips and dexterity were adversely affected by the bed posture. Lying in a hospital bed required greater pinch strength and dexterity to open packs. Eating in a seated position when in hospital has been shown to improve intake. The present study demonstrates that eating in a seated posture is also advantageous for opening the food and beverage packs used in the NSW hospital food service and supports the notion that patients should sit to eat in hospital. © 2016 The British Dietetic Association Ltd.

Exercise and Posture

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... About Spondylitis › Treatment Information › Exercise & Posture Print Page Exercise Exercise is an integral part of any spondylitis ... For First Responders For Chiropractors Research Article Archive Exercise Guidelines Having an exercise program that accomplishes your ...

[The impact of different sports on posture regulation].

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Schwesig, R; Kluttig, A; Leuchte, S; Becker, S; Schmidt, H; Esperer, H D

2009-09-01

Previous work has suggested that both the level of activity and the type of sport may have a major impact on postural control. However, no systematic investigation has been performed regarding the various types of professional sports. Particularly, the impact of competitional sports on the postural subsystems has not been elucidated so far. The aim of this study was to investigate the influence of the major professional sport types, such as handball, gymnastics, swimming, and shooting, on the subsystems of postural control. We also tested the hypothesis that specific types of sport have specific effects on postural regulation. 155 competitive male and female athletes (handball: n = 30; gymnastics: n = 44; swimming: n = 50; shooting: n = 31), and 34 age- and gender-matched controls were investigated using the Interactive Balance System (IBS; Tetrax Inc., Ramat Gan, Israel). The following spectral and time-domain indices were determined: power in the following frequency bands: P(F1) (0.03 - 0.1 Hz), P(F)(2 - 4) (0.1 - 0.5 Hz), P(F)(5 - 6) (0.5 - 1.0 Hz), P(F)(7 - 8) (> 1.0 Hz), stability index (STABI), and synchronisation index (SYN). Shooting athletes exhibited significantly smaller values of P(F1) (p = 0.003), P(F)(2 - 4) (p sports exert different effects on the various subsystems of posture control, where especially shooting competitors demonstrate a significantly better posture regulation. Those effects can be parameterised and quantified with the IBS which thus enables an efficient and purposeful training. Furthermore, the IBS is highly suitable for aptitude screening in sports with high posture regulatory demands (shooting competitions, gymnastics, diving etc.). Copyright Georg Thieme Verlag KG Stuttgart . New York .

Postural hygiene program to prevent low back pain.

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Méndez, F J; Gómez-Conesa, A

2001-06-01

A quasi-experimental study with 3 x 4 design was performed. To improve the level of knowledge and motor skills and thereby avert the development of painful symptoms. Despite the fact that low back pain affects a high percentage of the population, little research has been carried out to prevent low back pain through health education. The participants in this study were 106 third-grade (9-year-old) students. The program included 11 sessions. The teacher attended the placebo group sessions. No intervention was used with the control group. The level of knowledge and motor skills in the experimental group showed a significant increase immediately after the intervention finished, and at 6- and 12-month intervals after completion of the postural hygiene program (P = 0.00). Some positive changes were generalized to natural situations (P = 0.00). In an independent health check carried out by the local school health services 4 years after application of the postural hygiene program, the results tended slightly to favor the experimental condition over the control conditions (placebo + no intervention). A greater number of the control subjects required medical treatment for low back pain, although this difference was only marginally significant (P = 0.07). The findings from this study support the hypothesis that programs involving practice and motivating strategies impart health knowledge and habits more efficiently than those restricted to the mere transmission of information.

The effects of a high-intensity free-weight back-squat exercise protocol on postural stability in resistance-trained males.

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Thiele, R M; Conchola, E C; Palmer, T B; DeFreitas, J M; Thompson, B J

2015-01-01

The purpose of this study was to investigate the effects of a high-intensity free-weight back-squat exercise on postural stability characteristics in resistance-trained males. Eighteen college-aged (mean ± SD: age = 22.9 ± 2.9 years; height = 175.8 ± 6.4 cm; mass = 86.3 ± 9.3 kg), resistance-trained males performed postural stability testing before and after completing five sets of eight repetitions of back-squat exercises at 80% of one-repetition maximum. A commercial balance testing device was used to assess sway index at pre- and at 0, 5, 10, 15 and 20 min post-exercise. Each balance assessment consisted of four, 20-s static stance conditions: eyes-open firm surface, eyes-closed firm surface, eyes-open soft surface and eyes-closed soft surface. Sway index was greater (P = 0.001-0.020) at Post 0 than at all other time points. No differences (P > 0.05) were observed between any other time phases. Sway index was greater (P squat; however, sway index recovered within 5 min of exercise. Higher sway index values as a result of neuromuscular fatigue induced by a back-squat exercise may have performance and injury risk consequences to subsequent activities that rely on postural stability. However, these findings suggest balance impairments may recover in ~5 min following high-intensity lower body resistance exercise.

Yoga Training Has Positive Effects on Postural Balance and Its Influence on Activities of Daily Living in People with Multiple Sclerosis: A Pilot Study.

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de Oliveira, Gerson; Tavares, Maria da Consolação Cunha Gomes Fernandes; de Faria Oliveira, Jane Domingues; Rodrigues, Marcos Rojo; Santaella, Danilo Forghieri

2016-01-01

There is a little evidence about the influence of yoga as a complementary therapy for postural balance and its influence on activities of daily living in multiple sclerosis (MS) patients. To evaluate the influence of a six-month yoga program on postural balance and subjective impact of postural balance impairment on activities of daily living in people with MS. Randomized controlled pilot study. Protocol developed at the Adaptive Physical Activity Study Department, College of Physical Education, State University of Campinas, Brazil. A total of 12 (11 women) yoga naive people with MS randomly divided into two groups as follows: Control (C-waiting list, n = 6) and Yoga (Y-Yoga training, n = 6). Yoga group practiced postures, breathing exercises, meditation, and relaxation on weekly 60-min classes for a six-month period. The following evaluations were performed at study entry (baseline), and after six months (six months): Berg Balance Scale (BBS), Expanded Disability Status Scale (EDSS), and self-reported postural balance quality and influence of postural balance on activities of daily living. There was a significant improvement in BBS score from baseline to six months only in the Yoga group, especially in subjects with higher EDSS score, with increased quality of self-reported postural balance, and decreased influence of postural balance impairment on activities of daily living. In conclusion, a six-month yoga training is beneficial for people with MS, since it improves postural balance and decreases the influence of postural balance impairment on activities of daily living. A greater sample size is necessary to increase generalization, but it seems that yoga could be included as a feasible complementary therapy for people with MS. Copyright © 2016 Elsevier Inc. All rights reserved.

Eye Movements Affect Postural Control in Young and Older Females.

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Thomas, Neil M; Bampouras, Theodoros M; Donovan, Tim; Dewhurst, Susan

2016-01-01

Visual information is used for postural stabilization in humans. However, little is known about how eye movements prevalent in everyday life interact with the postural control system in older individuals. Therefore, the present study assessed the effects of stationary gaze fixations, smooth pursuits, and saccadic eye movements, with combinations of absent, fixed and oscillating large-field visual backgrounds to generate different forms of retinal flow, on postural control in healthy young and older females. Participants were presented with computer generated visual stimuli, whilst postural sway and gaze fixations were simultaneously assessed with a force platform and eye tracking equipment, respectively. The results showed that fixed backgrounds and stationary gaze fixations attenuated postural sway. In contrast, oscillating backgrounds and smooth pursuits increased postural sway. There were no differences regarding saccades. There were also no differences in postural sway or gaze errors between age groups in any visual condition. The stabilizing effect of the fixed visual stimuli show how retinal flow and extraocular factors guide postural adjustments. The destabilizing effect of oscillating visual backgrounds and smooth pursuits may be related to more challenging conditions for determining body shifts from retinal flow, and more complex extraocular signals, respectively. Because the older participants matched the young group's performance in all conditions, decreases of posture and gaze control during stance may not be a direct consequence of healthy aging. Further research examining extraocular and retinal mechanisms of balance control and the effects of eye movements, during locomotion, is needed to better inform fall prevention interventions.

A comparison of the posture between young female handball players and non-training peers.

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Grabara, Małgorzata

2014-01-01

To evaluate and compare the posture in young female handball players and a group of non-training peers. 125 handball players and 135 non-training individuals as a control group. All the subjects were aged 12-15. Measurements of basic somatic parameters (body height and mass, BMI, fat mass and total body water) were taken with an electronic balance 'Tanita'. The posture was evaluated using the moiré method. We analysed the shape of the spine in the sagittal plane and the position of the spine, pelvis and shoulder girdle in terms of symmetry. In 13-year-old handball players there was a smaller inclination of the thoracolumbar segment and a greater forward tilt of the torso. Among the training 15-year-olds, the inclination of the lower back, the sum of angles of anteroposterior curvatures and the angle of lumbar lordosis were smaller than in their non-training peers. Moreover, a correct pelvic alignment in the frontal plane, and pelvis and scapulas asymmetries in the transverse plane were more common in handball players. The formation of anteroposterior curvatures of the spine diversified some of the age groups of training and non-training young females. Handball training can affect the quality of posture.

[Self-evaluation of posture by elderly people with or without thoracic kyphosis].

Science.gov (United States)

Gasparotto, Lívia Pimenta Renó; Reis, Camila Costa Ibiapina; Ramos, Luiz Roberto; Santos, José Francisco Quirino Dos

2012-03-01

This article lists the differences between self-perception of body posture among the elderly suffering from postural alterations or not, in order to ascertain whether self-evaluation of posture can lead to preventive measures. Eighteen cases from the elderly population participated in the EPIDOSO project at UNIFESP and were subjected to postural evaluation. Postures were photographed and copies given to the participants and their subsequent comments were analyzed by the qualitative method. The narratives were taped and cataloguedusingthe technique of theoretical axial and selective coding from the perspective of symbolic interactionism. A passive attitude was identified among the elderly in relation to postural alterations. There is a distortion of body image by those with postural deviation. Participants with adequate spinal alignment were more conscious about body posture and the importance of this being assimilated in the phases prior to aging. The adoption of postural self-care seems to occur in the earlier stages of aging and preventive measures should be implemented at this stage. Lack of concern about posture is linked to the concept of the elderly regarding the notion that aging is, in itself, the accumulation of inevitably simultaneous or successive dysfunctions.

Posture-Motor and Posture-Ideomotor Dual-Tasking: A Putative Marker of Psychomotor Retardation and Depressive Rumination in Patients With Major Depressive Disorder.

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Aftanas, Lyubomir I; Bazanova, Olga M; Novozhilova, Nataliya V

2018-01-01

Background: Recent studies have demonstrated that the assessment of postural performance may be a potentially reliable and objective marker of the psychomotor retardation (PMR) in the major depressive disorder (MDD). One of the important facets of MDD-related PMR is reflected in disrupted central mechanisms of psychomotor control, heavily influenced by compelling maladaptive depressive rumination. In view of this we designed a research paradigm that included sequential execution of simple single-posture task followed by more challenging divided attention posture tasks, involving concurring motor and ideomotor workloads. Another difficulty dimension assumed executing of all the tasks with eyes open (EO) (easy) and closed (EC) (difficult) conditions. We aimed at investigating the interplay between the severity of MDD, depressive rumination, and efficiency of postural performance. Methods: Compared with 24 age- and body mass index-matched healthy controls (HCs), 26 patients with MDD sequentially executed three experimental tasks: (1) single-posture task of maintaining a quiet stance (ST), (2) actual posture-motor dual task (AMT); and (3) mental/imaginary posture-motor dual task (MMT). All the tasks were performed in the EO and the EC conditions. The primary dependent variable was the amount of kinetic energy ( E ) expended for the center of pressure deviations (CoPDs), whereas the absolute divided attention cost index showed energy cost to the dual-tasking vs. the single-posture task according to the formula: Δ E = ( E Dual-task - E Single-task ). Results: The signs of PMR in the MDD group were objectively indexed by deficient posture control in the EC condition along with overall slowness of fine motor and ideomotor activity. Another important and probably more challenging feature of the findings was that the posture deficit manifested in the ST condition was substantially and significantly attenuated in the MMT and AMT performance dual-tasking activity. A multiple

Impaired perception of surface tilt in progressive supranuclear palsy.

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Marian L Dale

Full Text Available Progressive supranuclear palsy (PSP is characterized by early postural instability and backward falls. The mechanisms underlying backward postural instability in PSP are not understood. The aim of this study was to test the hypothesis that postural instability in PSP is a result of dysfunction in the perception of postural verticality.We gathered posturography data on 12 subjects with PSP to compare with 12 subjects with idiopathic Parkinson's Disease (PD and 12 healthy subjects. Objective tests of postural impairment included: dynamic sensory perception tests of gravity and of surface oscillations, postural responses to surface perturbations, the sensory organization test of postural sway under altered sensory conditions and limits of stability in stance.Perception of toes up (but not toes down surface tilt was reduced in subjects with PSP compared to both control subjects (p≤0.001 standing, p≤0.007 seated and subjects with PD (p≤0.03 standing, p≤0.04 seated. Subjects with PSP, PD and normal controls accurately perceived the direction of gravity when standing on a tilting surface. Unlike PD and control subjects, subjects with PSP exerted less postural corrective torque in response to toes up surface tilts.Difficulty perceiving backward tilt of the surface or body may account for backward falls and postural impairments in patients with PSP. These observations suggest that abnormal central integration of sensory inputs for perception of body and surface orientation contributes to the pathophysiology of postural instability in PSP.

Análise comparativa entre avaliação postural visual e por fotogrametria computadorizada Comparative analysis between visual and computerized photogrammetry postural assessment

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DH Iunes

2009-08-01

Full Text Available OBJETIVOS: Comparar a concordância interobservador da avaliação postural visual e por fotogrametria e verificar se os resultados quantitativos da fotogrametria correspondem à detecção de simetrias e assimetrias pela avaliação postural visual qualitativa. MÉTODOS: Vinte e um voluntários (24±1,9 anos foram inicialmente avaliados visualmente por três fisioterapeutas experientes que preencheram um protocolo de avaliação postural. Em seguida tiveram fotografados a face e o corpo todo nos planos frontal anterior, posterior e sagital. As fotos foram utilizadas para traçar ângulos a partir de marcadores fixados à pele, em vários pontos anatômicos, que são referências frequentes na avaliação postural tradicional. Essas fotografias foram analisadas por três examinadores diferentes da avaliação postural visual. A concordância de cada método de avaliação postural foi avaliada pelos Coeficientes de Cramer V ou de PHI, considerando-se um nível de significância de 5%. RESULTADOS: Foi encontrada uma concordância entre os examinadores que utilizaram a fotogrametria para todos os segmentos avaliados. Não apresentaram concordância os segmentos comissura labial (p=0,00, acrômio clavicular (p=0,01, esternoclavicular (p=0,00, espinhas ilíacas anterior e posterior (p=0,00 e p=0,01 e ângulo inferior da escápula (p=0,00, que foram analizados por meio da avaliação postural visual. A comparação entre a fotogrametria e a avaliação postural visual demonstrou que o grau de concordância entre os dois métodos de avaliação foi pouco significativo para alguns segmentos do membro inferior e pelve. CONCLUSÕES: Nessas condições experimentais, os dados da fotogrametria não podem ser correlacionados com os dados da avaliação postural visual. A avaliação postural visual apresentou dados menos concordantes do que a fotogrametria, devendo ser questionada sua utilização como gold-standart.OBJECTIVES: To compare the interobserver

Development of anticipatory postural adjustments during locomotion in children.

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Hirschfeld, H; Forssberg, H

1992-08-01

1. Anticipatory postural adjustments were studied in children (6-14 yr of age) walking on a treadmill while pulling a handle. Electromyographs (EMGs) and movements were recorded from the left arm and leg. 2. Postural activity in the leg muscles preceded voluntary arm muscle activity in all age groups, including the youngest children (6 yr of age). The latency to both leg and arm muscle activity, from a triggering audio signal, decreased with age. 3. In older children the latency to both voluntary and postural activity was influenced by the phase of the step cycle. The shortest latency to the first activated postural muscle occurred during single support phase in combination with a long latency to arm muscle activity. 4. In the youngest children, there was no phase-dependent modulation of the latency to the activation of the postural muscles. The voluntary activity was delayed during the beginning of the support phase resulting in a long delay between leg and arm muscle activity. 5. The postural muscle activation pattern was modified in a phase-dependent manner in all children. Lateral gastrocnemius (LG) and hamstring muscles (HAM) were activated during the early support phase, whereas tibialis anterior (TA) and quadriceps (Q) muscles were activated during the late support phase and during the swing phase. However, in the 6-yr-old children, LG was also activated in the swing phase. LG was activated before the HAM activity in the youngest children but after HAM in 14-yr-old children and adults. 6. The occurrence of LG activity in postural responses before heel strike suggests an immature (nonplantigrade) gating of postural activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Foot posture in basketball players with history of the shin splint

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Saeed Forghany

2013-07-01

Full Text Available Introduction: Shin splint is one of the common injuries in most athletes. Although the relationship between abnormal foot posture and shin splint has been reported previously but, the relation between foot posture and shin splint has not been well documented. The aim of this study was to explore the relationship between foot postures in basketball players and the history of shin splint. Materials and Methods: Thirty Iranian male basketball players who had experience of shin splint during last three months were participated in this study. Foot Posture Index (FPI-6 was used as the measure of foot posture. Talar head palpation, curvature at the lateral malleoli, inversion/eversion of the calcaneus, prominence in the region of the talonavicular joint, congruence of the medial longitudinal arch, abduction /adduction of the forefoot on the rear foot were 6 items which were assessed with FPI in the standing position. Foot posture was defined as ‘normal’, ‘supinated’ or ‘pronated. Data were collected and analyzed by SPSS, version16. Results: Most participants showed abnormal foot posture (%80. Fifty-three percent of subjects had pronated foot (%53 and 10% did hyper-pronation. The foot postures of 17% of participants were in supination. The results of this study did not show a significant difference in foot posture between right and left foot (P > 0.05. Conclusion: abnormal foot posture were common (%80 in basketball players with the history of shin splints. These findings could support this idea that the footwear and orthotic prescription both can prevent and treat basketball players with history of shin splints. Keywords: Foot posture, Shin splints, Basketball

Use of Video Analysis System for Working Posture Evaluations

Science.gov (United States)

McKay, Timothy D.; Whitmore, Mihriban

1994-01-01

In a work environment, it is important to identify and quantify the relationship among work activities, working posture, and workplace design. Working posture may impact the physical comfort and well-being of individuals, as well as performance. The Posture Video Analysis Tool (PVAT) is an interactive menu and button driven software prototype written in Supercard (trademark). Human Factors analysts are provided with a predefined set of options typically associated with postural assessments and human performance issues. Once options have been selected, the program is used to evaluate working posture and dynamic tasks from video footage. PVAT has been used to evaluate postures from Orbiter missions, as well as from experimental testing of prototype glove box designs. PVAT can be used for video analysis in a number of industries, with little or no modification. It can contribute to various aspects of workplace design such as training, task allocations, procedural analyses, and hardware usability evaluations. The major advantage of the video analysis approach is the ability to gather data, non-intrusively, in restricted-access environments, such as emergency and operation rooms, contaminated areas, and control rooms. Video analysis also provides the opportunity to conduct preliminary evaluations of existing work areas.

Effect of absence of vision on posture.

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Alotaibi, Abdullah Z; Alghadir, Ahmad; Iqbal, Zaheen A; Anwer, Shahnawaz

2016-04-01

[Purpose] The visual system is one of the sensory systems that enables the body to assess and process information about the external environment. In the absence of vision, a blind person loses contact with the outside world and develops faulty motor patterns, which results in postural deficiencies. However, literature regarding the development of such deficiencies is limited. The aim of this study was to discuss the effect of absence of vision on posture, the possible biomechanics behind the resulting postural deficiencies, and strategies to correct and prevent them. [Subjects and Methods] Various electronic databases including PubMed, Medline, and Google scholar were examined using the words "body", "posture", "blind" and "absence of vision". References in the retrieved articles were also examined for cross-references. The search was limited to articles in the English language. [Results] A total of 74 papers were shortlisted for this review, most of which dated back to the 1950s and 60s. [Conclusion] Blind people exhibit consistent musculoskeletal deformities. Absence of vision leads to numerous abnormal sensory and motor interactions that often limit blind people in isolation. Rehabilitation of the blind is a multidisciplinary task. Specialists from different fields need to diagnose and treat the deficiencies of the blind together as a team. Before restoring the normal mechanics of posture and gait, the missing link with the external world should be reestablished.

Nonplantigrade Foot Posture: A Constraint on Dinosaur Body Size

OpenAIRE

Kubo, Tai; Kubo, Mugino O.

2016-01-01

Dinosaurs had functionally digitigrade or sub-unguligrade foot postures. With their immediate ancestors, dinosaurs were the only terrestrial nonplantigrades during the Mesozoic. Extant terrestrial mammals have different optimal body sizes according to their foot posture (plantigrade, digitigrade, and unguligrade), yet the relationship of nonplantigrade foot posture with dinosaur body size has never been investigated, even though the body size of dinosaurs has been studied intensively. Accordi...

Visual tasks and postural sway in children with and without autism spectrum disorders.

Science.gov (United States)

Chang, Chih-Hui; Wade, Michael G; Stoffregen, Thomas A; Hsu, Chin-Yu; Pan, Chien-Yu

2010-01-01

We investigated the influences of two different suprapostural visual tasks, visual searching and visual inspection, on the postural sway of children with and without autism spectrum disorder (ASD). Sixteen ASD children (age=8.75±1.34 years; height=130.34±11.03 cm) were recruited from a local support group. Individuals with an intellectual disability as a co-occurring condition and those with severe behavior problems that required formal intervention were excluded. Twenty-two sex- and age-matched typically developing (TD) children (age=8.93±1.39 years; height=133.47±8.21 cm) were recruited from a local public elementary school. Postural sway was recorded using a magnetic tracking system (Flock of Birds, Ascension Technologies, Inc., Burlington, VT). Results indicated that the ASD children exhibited greater sway than the TD children. Despite this difference, both TD and ASD children showed reduced sway during the search task, relative to sway during the inspection task. These findings replicate those of Stoffregen et al. (2000), Stoffregen, Giveans, et al. (2009), Stoffregen, Villard, et al. (2009) and Prado et al. (2007) and extend them to TD children as well as ASD children. Both TD and ASD children were able to functionally modulate postural sway to facilitate the performance of a task that required higher perceptual effort. Copyright © 2010 Elsevier Ltd. All rights reserved.

Correcting Poor Posture without Awareness or Willpower

Science.gov (United States)

Wernik, Uri

2012-01-01

In this article, a new technique for correcting poor posture is presented. Rather than intentionally increasing awareness or mobilizing willpower to correct posture, this approach offers a game using randomly drawn cards with easy daily assignments. A case using the technique is presented to emphasize the subjective experience of living with poor…

Saccadic Eye Movement Improves Plantar Sensation and Postural Balance in Elderly Women.

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Bae, Youngsook

2016-06-01

Vision, proprioception and plantar sensation contribute to the control of postural balance (PB). Reduced plantar sensation alters postural response and is at an increased risk of fall, and eye movements reduce the postural sway. Therefore, the aim of this study was to study the improvement of plantar sensation and PB after saccadic eye movement (SEM) and pursuit eye movement (PEM) in community-dwelling elderly women. Participants (104 females; 75.11 ± 6.25 years) were randomly allocated into the SEM group (n = 52) and PEM groups (n = 52). The SEM group performed eye fixation and SEM for 5 minutes, and the PEM group performed eye fixation and PEM for 5 minutes. The plantar sensation was measured according to the plantar surface area of the feet in contact with the floor surface before and after the intervention. Before and after SEM and PEM with the eyes open and closed, PB was measured as the area (mm(2)), length (cm), and velocity (cm/s) of the fluctuation of the center of pressure (COP). The plantar sensation of both feet improved in both groups (p eye open and close in both groups (p < 0.01). The length and velocity of the COP significantly decreased in the SEM group compared to the PEM group (p < 0.05). In conclusion, SEM and PEM are effective interventions for improving plantar sensation and PB in elderly women, with greater PB improvement after SEM.

Anisotropic gravitational instability

International Nuclear Information System (INIS)

Polyachenko, V.L.; Fridman, A.M.

1988-01-01

Exact solutions of stability problems are obtained for two anisotropic gravitational systems of different geometries - a layer of finite thickness at rest and a rotating cylinder of finite radius. It is shown that the anisotropic gravitational instability which develops in both cases is of Jeans type. However, in contrast to the classical aperiodic Jeans instability, this instability is oscillatory. The physics of the anisotropic gravitational instability is investigated. It is shown that in a gravitating layer this instability is due, in particular, to excitation of previously unknown interchange-Jeans modes. In the cylinder, the oscillatory Jeans instability is associated with excitation of a rotational branch, this also being responsible for the beam gravitational instability. This is the reason why this instability and the anisotropic gravitational instability have so much in common

LONGITUDINAL AND TRANSVERSAL PLASMA WAVE INSTABILITIES IN TWO COUNTERSTREAMING PLASMAS WITHOUT EXTERNAL FIELDS

Energy Technology Data Exchange (ETDEWEB)

Buenemann, D

1963-03-15

Some aspects of the theory of longitudinal and transversal waves in a collisionless nonrelativistic plasma are treated. A dispersion relation for multicomponent plasmas is derived from the linearized Boltzmann-Vlasov equation using the full set of Maxwell's equations without an external field. The velocity distributions of the plasma streams are assumed to be Maxwellian. For the particular case of two counterstreaming plasmas it is shown that there exists transversal instabilities for all counterstreaming velocities whereas the well known two stream instabilities only exist for velocities greater than a critical velocity. Exact solutions for the onset of the instabilities can be given. This kind of instability may occur for any nonisotropic velocity distribution in a collisionless plasma. (auth)

Effects of circumferential ankle pressure on ankle proprioception, stiffness, and postural stability: a preliminary investigation.

Science.gov (United States)

You, Sung H; Granata, Kevin P; Bunker, Linda K

2004-08-01

Cross-sectional repeated-measures design. Determine the effects of circumferential ankle pressure (CAP) intervention on proprioceptive acuity, ankle stiffness, and postural stability. The application of CAP using braces, taping, and adaptive shoes or military boots is widely used to address chronic ankle instability (CAI). An underlying assumption is that the CAP intervention might improve ankle stability through increased proprioceptive acuity and stiffness in the ankle. METHOD AND MEASURES: A convenience sample of 10 subjects was recruited from the local university community and categorized according to proprioceptive acuity (high, low) and ankle stability (normal, CAI). Proprioceptive acuity was measured when blindfolded subjects were asked to accurately reproduce a self-selected target ankle position before and after the application of CAP. Proprioceptive acuity was determined in 5 different ankle joint position sense tests: neutral, inversion, eversion, plantar flexion, and dorsiflexion. Joint position angles were recorded electromechanically using a potentiometer. Passive ankle stiffness was computed from the ratio of applied static moment versus angular displacement. Active ankle stiffness was determined from biomechanical analyses of ankle motion following a mediolateral perturbation. Postural stability was quantified from the center of pressure displacement in the mediolateral and the anteroposterior directions in unipedal stance. All measurements were recorded with and without CAP applied by a pediatric blood pressure cuff. Data were analyzed using a separate mixed-model analysis of variance (ANOVA) for each dependent variable. Post hoc comparison using Tukey's honestly significant difference (HSD) test was performed if significant interactions were obtained. Significance level was set at P<.05 for all analyses. Significant group (high versus low proprioceptive acuity) x CAP interactions were identified for postural stability. Passive ankle stiffness was

Lung function and postural changes during pregnancy.

Science.gov (United States)

Nørregaard, O; Schultz, P; Ostergaard, A; Dahl, R

1989-11-01

The aim of this study was to determine the effects of postural changes on lung function in pregnant women during the first, second, third trimester and post partum. A significant decrease in FRC, PEF and FEV1 was observed as a result of the postural changes. Arterial oxygenation, MVV and DLCO remained largely the same.

Relationship between posterior crossbite and postural alterations in children

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Juliana Jaqueline de Matos Lopes

2009-12-01

Full Text Available Objective: To evaluate the posture of individuals with functional posterior crossbite, malocclusion is one of the most in need of orthodontic treatment. Methods: This work presents an analysis of postural among children 6 to 12 years who present functional posterior cross bite of both genders who are in mixed dentition or no intervention prior orthodontic and orthopedic. Was obtained images in the plans: front and back where it was analyzed the asymmetry or symmetry of the individual in the image and in the lateral, anterior, a posterior or normality. Results: 100% had some kind of postural change, and the asymmetry between the scapulae (shoulder found the greatest change, as one of extreme importance in this age group represents a growing skeletal muscle. Conclusion: analyzes all of the children showed postural abnormalities and malocclusion are also of great importance not only to be treating the problem orally, but the postural problem with the help of a multidisciplinary team.

Effect of postural changes on ICP in healthy and ill subjects

DEFF Research Database (Denmark)

Petersen, Lonnie G; Juhler, Marianne

2015-01-01

to distinguish normal human physiology from disease entities such as idiopathic intracranial hypertension and normal pressure hydrocephalus, we investigated ICP in different body postures in both normal and ill subjects. METHODS: Thirty-one patients were included: four normal patients following complete removal......: upright standing, sitting in a chair, supine and right lateral lumbar puncture position. RESULTS: Linear regression of median ICP based on patient posture, group, and purpose of monitoring presented a significant model (p ... of differences in median ICP between body postures and supine ICP as the baseline, presented a highly significant model (p posture (p postures enabled...

Causes, Prevention and Correction of Impaired Posture in Children of Primary School Age

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В. А. Щирба

2016-09-01

Full Text Available Research Objective. The objective of our research was to provide theoretical substantiation and implement corrective gymnastics in practice for the purposes of prevention and correction of faults in schoolchildren’s posture. The main means for shaping the correct posture, preventing and correcting faults in posture are callisthenic routine and special corrective exercises. Research methods: anamnesis, somatoscopy, clinical and mathematical methods. Research results. The medical examination revealed that only six of 60 pupils had normal correctly shaped posture, which accounts for 10%. The posture of the other 90% of the pupils was impaired. The most common faults were: asymmetrical pectoral girdle and shoulder blades, stooping posture. The examination revealed 19 pupils with scoliotic posture, which accounts for 44 %. The posture of 24 pupils, or 40%, was hyperkyphotic and stooping. In other words, the posture of 84% of the pupils was scoliotic or hyperkyphotic. The rest of the pupils had flat and kypholordic posture. It is worth mentioning that some of the pupils examined had more serious disorders of their musculoskeletal system, namely: organic disorders, such as spinal disorders in the sagittal plane — the scoliosis types excluded from the study. Significantly, the first main reason of posture disorders is weakness of the pectoral muscle sling. Conclusions. The principal means of prevention and correction of impaired posture are using special physical exercises designed to create a muscular corpus and correct particular faults in posture. We therefore developed sets of exercises intended to correct posture defects and proposed them to the physical education teacher and class teachers.

The SOL width and the MHD interchange instability in tokamaks

Energy Technology Data Exchange (ETDEWEB)

Kerner, W [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking; Pogutse, O [Kurchatov institute, Moscow (Russian Federation)

1994-07-01

Instabilities in the SOL plasma can strongly influence the SOL plasma behaviour and in particular the SOL width. The SOL stability analysis shows that there exists a critical ratio of the thermal energy and the magnetic energy. If the SOL beta is greater than this critical value, the magnetic field cannot prevent the plasma displacement and a strong MHD instability in the SOL occurs. In the opposite case only slower resistive instabilities can develop. A theoretical investigation of the SOL plasma stability is presented for JET single-null and double-null divertor configurations. The dependence of the stability threshold on the SOL beta and on the sheath resistance is established. Applying a simple mixing length argument gives the scaling of the SOL width. 5 refs., 2 figs.

Time-of-day influences postural balance in older adults

DEFF Research Database (Denmark)

Jorgensen, M G; Rathleff, Michael Skovdal; Laessoe, U

2012-01-01

Postural balance assessments are performed in both clinical and basic research settings on a daily basis. During a 24-h time span our physiology and physical performance undergo radical changes as we are influenced by the circadian rhythm. The time-of-day interaction on postural balance is unknow...... in older adults. The aim of this study was to investigate the time-of-day effect on postural balance in older adults....

Can smartwatches replace smartphones for posture tracking?

Science.gov (United States)

Mortazavi, Bobak; Nemati, Ebrahim; VanderWall, Kristina; Flores-Rodriguez, Hector G; Cai, Jun Yu Jacinta; Lucier, Jessica; Naeim, Arash; Sarrafzadeh, Majid

2015-10-22

This paper introduces a human posture tracking platform to identify the human postures of sitting, standing or lying down, based on a smartwatch. This work develops such a system as a proof-of-concept study to investigate a smartwatch's ability to be used in future remote health monitoring systems and applications. This work validates the smartwatches' ability to track the posture of users accurately in a laboratory setting while reducing the sampling rate to potentially improve battery life, the first steps in verifying that such a system would work in future clinical settings. The algorithm developed classifies the transitions between three posture states of sitting, standing and lying down, by identifying these transition movements, as well as other movements that might be mistaken for these transitions. The system is trained and developed on a Samsung Galaxy Gear smartwatch, and the algorithm was validated through a leave-one-subject-out cross-validation of 20 subjects. The system can identify the appropriate transitions at only 10 Hz with an F-score of 0.930, indicating its ability to effectively replace smart phones, if needed.

Static body postural misalignment in individuals with temporomandibular disorders: a systematic review

Science.gov (United States)

Chaves, Thaís C.; Turci, Aline M.; Pinheiro, Carina F.; Sousa, Letícia M.; Grossi, Débora B.

2014-01-01

BACKGROUND: The association between body postural changes and temporomandibular disorders (TMD) has been widely discussed in the literature, however, there is little evidence to support this association. OBJECTIVES: The aim of the present study was to conduct a systematic review to assess the evidence concerning the association between static body postural misalignment and TMD. METHOD: A search was conducted in the PubMed/Medline, Embase, Lilacs, Scielo, Cochrane, and Scopus databases including studies published in English between 1950 and March 2012. Cross-sectional, cohort, case control, and survey studies that assessed body posture in TMD patients were selected. Two reviewers performed each step independently. A methodological checklist was used to evaluate the quality of the selected articles. RESULTS: Twenty studies were analyzed for their methodological quality. Only one study was classified as a moderate quality study and two were classified as strong quality studies. Among all studies considered, only 12 included craniocervical postural assessment, 2 included assessment of craniocervical and shoulder postures,, and 6 included global assessment of body posture. CONCLUSION: There is strong evidence of craniocervical postural changes in myogenous TMD, moderate evidence of cervical postural misalignment in arthrogenous TMD, and no evidence of absence of craniocervical postural misalignment in mixed TMD patients or of global body postural misalignment in patients with TMD. It is important to note the poor methodological quality of the studies, particularly those regarding global body postural misalignment in TMD patients. PMID:25590441

Static and Dynamic Postural Changes after a Mountain Ultra-Marathon of 80 km and 5500 D.

Directory of Open Access Journals (Sweden)

Giuseppe Marcolin

Full Text Available The study aimed to investigate the effect of fatigue on static and dynamic postural stability after completing a mountain ultra-marathon. Twelve male athletes participated in the study. Postural stability was assessed before and immediately after the race. Static postural stability was evaluated on a dynamometric platform with eyes opened (OE and closed (CE. Dynamic postural stability was assessed with OE on an instrumented plate which allowed medio-lateral oscillations. Stabilometric data were affected by fatigue in the OE condition, concerning sway path velocity (p = 0.0006, sway area velocity (p = 0.0006, area of the confidence ellipse (p = 0.0016, maximal anterior-posterior (AP (p = 0.0017 and medio-lateral (ML (p = 0.0039 oscillations. In the CE condition the sway path velocity (p = 0.0334, the maximal ML oscillations (p = 0.0161 and the area of the confident ellipse (p = 0.0180 were also negatively influenced. Stabilogram diffusion analysis showed in the OE condition an increase of short-term diffusion coefficients considering the anterior-posterior direction (Dfys; p = 0.0023 and the combination of the two (Dfr2s; p = 0.0032. Equally, long term diffusion coefficients increased considering the anterior-posterior direction (Dfyl; p = 0.0093 and the combination of the two (Dfr2l; p = 0.0086. In CE condition greater values were detected for medio-lateral direction (Dfxl; p = 0.033, anterior-posterior direction (Dfyl; p = 0.0459 and the combination of the two (Dfr2l; p = 0.0048. The dynamic postural stability test showed an increase of the time spent with the edges of the plate on the floor (p = 0.0152. Our results showed that mountain ultra-marathon altered static stability more than dynamic stability. An involvement of cognitive resources to monitor postural stability after fatiguing could be the explanation of the worsening in the automatic task (quiet standing and of the positive compensation in the less automatic task (dynamic standing on

Posture recognition based on fuzzy logic for home monitoring of the elderly.

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Brulin, Damien; Benezeth, Yannick; Courtial, Estelle

2012-09-01

We propose in this paper a computer vision-based posture recognition method for home monitoring of the elderly. The proposed system performs human detection prior to the posture analysis; posture recognition is performed only on a human silhouette. The human detection approach has been designed to be robust to different environmental stimuli. Thus, posture is analyzed with simple and efficient features that are not designed to manage constraints related to the environment but only designed to describe human silhouettes. The posture recognition method, based on fuzzy logic, identifies four static postures and is robust to variation in the distance between the camera and the person, and to the person's morphology. With an accuracy of 74.29% of satisfactory posture recognition, this approach can detect emergency situations such as a fall within a health smart home.

Spatial and temporal analysis of postural control in dyslexic children.

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Gouleme, Nathalie; Gerard, Christophe Loic; Bui-Quoc, Emmanuel; Bucci, Maria Pia

2015-07-01

The aim of this study is to examine postural control of dyslexic children using both spatial and temporal analysis. Thirty dyslexic (mean age 9.7±0.3years) and thirty non-dyslexic age-matched children participated in the study. Postural stability was evaluated using Multitest Equilibre from Framiral®. Posture was recorded in the following conditions: eyes open fixating a target (EO) and eyes closed (EC) on stable (-S-) and unstable (-U-) platforms. The findings of this study showed poor postural stability in dyslexic children with respect to the non-dyslexic children group, as demonstrated by both spatial and temporal analysis. In both groups of children postural control depends on the condition, and improves when the eyes are open on a stable platform. Dyslexic children have spectral power indices that are higher than in non-dyslexic children and they showed a shorter cancelling time. Poor postural control in dyslexic children could be due to a deficit in using sensory information most likely caused by impairment in cerebellar activity. The reliability of brain activation patterns, namely in using sensory input and cerebellar activity may explain the deficit in postural control in dyslexic children. Copyright © 2014 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Regional differences in lumbar spinal posture and the influence of low back pain

Directory of Open Access Journals (Sweden)

Burnett Angus F

2008-11-01

Full Text Available Abstract Background Spinal posture is commonly a focus in the assessment and clinical management of low back pain (LBP patients. However, the link between spinal posture and LBP is not fully understood. Recent evidence suggests that considering regional, rather than total lumbar spine posture is important. The purpose of this study was to determine; if there are regional differences in habitual lumbar spine posture and movement, and if these findings are influenced by LBP. Methods One hundred and seventy female undergraduate nursing students, with and without LBP, participated in this cross-sectional study. Lower lumbar (LLx, Upper lumbar (ULx and total lumbar (TLx spine angles were measured using an electromagnetic tracking system in static postures and across a range of functional tasks. Results Regional differences in lumbar posture and movement were found. Mean LLx posture did not correlate with ULx posture in sitting (r = 0.036, p = 0.638, but showed a moderate inverse correlation with ULx posture in usual standing (r = -0.505, p Conclusion This study supports the concept of regional differences within the lumbar spine during common postures and movements. Global lumbar spine kinematics do not reflect regional lumbar spine kinematics, which has implications for interpretation of measures of spinal posture, motion and loading. BMI influenced regional lumbar posture and movement, possibly representing adaptation due to load.

Real-Time Hand Posture Recognition Using a Range Camera

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Lahamy, Herve

The basic goal of human computer interaction is to improve the interaction between users and computers by making computers more usable and receptive to the user's needs. Within this context, the use of hand postures in replacement of traditional devices such as keyboards, mice and joysticks is being explored by many researchers. The goal is to interpret human postures via mathematical algorithms. Hand posture recognition has gained popularity in recent years, and could become the future tool for humans to interact with computers or virtual environments. An exhaustive description of the frequently used methods available in literature for hand posture recognition is provided. It focuses on the different types of sensors and data used, the segmentation and tracking methods, the features used to represent the hand postures as well as the classifiers considered in the recognition process. Those methods are usually presented as highly robust with a recognition rate close to 100%. However, a couple of critical points necessary for a successful real-time hand posture recognition system require major improvement. Those points include the features used to represent the hand segment, the number of postures simultaneously recognizable, the invariance of the features with respect to rotation, translation and scale and also the behavior of the classifiers against non-perfect hand segments for example segments including part of the arm or missing part of the palm. A 3D time-of-flight camera named SR4000 has been chosen to develop a new methodology because of its capability to provide in real-time and at high frame rate 3D information on the scene imaged. This sensor has been described and evaluated for its capability for capturing in real-time a moving hand. A new recognition method that uses the 3D information provided by the range camera to recognize hand postures has been proposed. The different steps of this methodology including the segmentation, the tracking, the hand

POSTURAL SHOCK IN PREGNANCY

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Wilkening, Ralph L.; Knauer, John; Larson, Roger K.

1955-01-01

Signs and symptoms of shock may be produced in some patients in late pregnancy by putting them in the dorsal recumbent posture. Change from this position will relieve the condition. The features of the supine hypotensive syndrome can be duplicated by applying pressure to the abdomen with the patient in a lateral position. The postural variations of venous pressure, blood pressure, and pulse appear to be due to obstruction of venous return from the lower portion of the body caused by the large uterus of late pregnancy compressing the vena cava. When shock is observed in a woman in late pregnancy, she should be turned to a lateral position before more active measures of treatment are begun. ImagesFigure 1. PMID:14351983

Meta-analysis: association between wrist posture and carpal tunnel syndrome among workers.

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You, Doohee; Smith, Allan H; Rempel, David

2014-03-01

Carpal tunnel syndrome (CTS) is a common work-related peripheral neuropathy. In addition to grip force and repetitive hand exertions, wrist posture (hyperextension and hyperflexion) may be a risk factor for CTS among workers. However, findings of studies evaluating the relationship between wrist posture and CTS are inconsistent. The purpose of this paper was to conduct a meta-analysis of existing studies to evaluate the evidence of the relationship between wrist posture at work and risk of CTS. PubMed and Google Scholar were searched to identify relevant studies published between 1980 and 2012. The following search terms were used: "work related", "carpal tunnel syndrome", "wrist posture", and "epidemiology". The studies defined wrist posture as the deviation of the wrist in extension or flexion from a neutral wrist posture. Relative risk (RR) of individual studies for postural risk was pooled to evaluate the overall risk of wrist posture on CTS. Nine studies met the inclusion criteria. All were cross-sectional or case-control designs and relied on self-report or observer's estimates for wrist posture assessment. The pooled RR of work-related CTS increased with increasing hours of exposure to wrist deviation or extension/flexion [RR = 2.01; 95% confidence interval (CI): 1.646-2.43; p Workplace interventions to prevent CTS should incorporate training and engineering interventions that reduce sustained non-neutral wrist postures.

Measuring postural sway in sitting

DEFF Research Database (Denmark)

Curtis, Derek John; Hansen, Lisbeth; Luun, Malene

2015-01-01

group appeared to result from an equally stable trunk supported on a less stable pelvis. Mediolateral marker sway and intersegmental angular sway showed a clearer age dependency. Trunk postural control does not appear to differ between children older and younger than 10 years old, but sagittal plane...... and younger than 10 years old, participated in this study. The children sat unsupported for 30 s while their posture and sway were quantified using stereophotogrammetry. The tendency in both age groups was to sit with a backward tilted pelvis and a kyphotic trunk. The sitting position was most varied...

Parametric instabilities in an electron beam-plasma system: magnetic field effects

International Nuclear Information System (INIS)

Gell, Y.; Levush, B.; Nakach, R.

1981-09-01

The effects of a magnetic field on the excitation of low-frequency parametric instabilities in a beam-plasma system are considered. The dispersion relation of the three-dimensional beamless configuration, is analytically evaluated for an electrostatic pump wave having a finite wave-vector parallel to the magnetic field. The results of this analysis serve as a guide to the numerical study of the stability of the involved system including the beam. As for the one-dimensional case, one finds that two low-frequency electrostatic instability branches having different growth rates may exist simultaneously. The effects of the magnetic field on these instabilities could be summarized as follows: the small growth rate instability is negligibly small when the electron gyrofrequency is about equal to the pump wave frequency. This instability is magnetic field independent for high enough values of the field. When the plasma electron Debye length is greater than the beam electron Debye length, a large growth rate instability is excited and appears to be weakly dependent on the magnetic field, while the two instability branches are quite sensitive to change of the magnetic field, when the two Debye lengths are equal. Other characteristics of this system are also discussed

A new methodology based on functional principal component analysis to study postural stability post-stroke.

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Sánchez-Sánchez, M Luz; Belda-Lois, Juan-Manuel; Mena-Del Horno, Silvia; Viosca-Herrero, Enrique; Igual-Camacho, Celedonia; Gisbert-Morant, Beatriz

2018-05-05

A major goal in stroke rehabilitation is the establishment of more effective physical therapy techniques to recover postural stability. Functional Principal Component Analysis provides greater insight into recovery trends. However, when missing values exist, obtaining functional data presents some difficulties. The purpose of this study was to reveal an alternative technique for obtaining the Functional Principal Components without requiring the conversion to functional data beforehand and to investigate this methodology to determine the effect of specific physical therapy techniques in balance recovery trends in elderly subjects with hemiplegia post-stroke. A randomized controlled pilot trial was developed. Thirty inpatients post-stroke were included. Control and target groups were treated with the same conventional physical therapy protocol based on functional criteria, but specific techniques were added to the target group depending on the subjects' functional level. Postural stability during standing was quantified by posturography. The assessments were performed once a month from the moment the participants were able to stand up to six months post-stroke. The target group showed a significant improvement in postural control recovery trend six months after stroke that was not present in the control group. Some of the assessed parameters revealed significant differences between treatment groups (P Functional Principal Component Analysis to be performed when data is scarce. Moreover, it allowed the dynamics of recovery of two different treatment groups to be determined, showing that the techniques added in the target group increased postural stability compared to the base protocol. Copyright © 2018 Elsevier Ltd. All rights reserved.

Multi-joint postural behavior in patients with knee osteoarthritis.

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Turcot, Katia; Sagawa, Yoshimasa; Hoffmeyer, Pierre; Suvà, Domizio; Armand, Stéphane

2015-12-01

Previous studies have demonstrated balance impairment in patients with knee osteoarthritis (OA). Although it is currently accepted that postural control depends on multi-joint coordination, no study has previously considered this postural strategy in patients suffering from knee OA. The objectives of this study were to investigate the multi-joint postural behavior in patients with knee OA and to evaluate the association with clinical outcomes. Eighty-seven patients with knee OA and twenty-five healthy elderly were recruited to the study. A motion analysis system and two force plates were used to investigate the joint kinematics (trunk and lower body segments), the lower body joint moments, the vertical ground reaction force ratio and the center of pressure (COP) during a quiet standing task. Pain, functional capacity and quality of life status were also recorded. Patients with symptomatic and severe knee OA adopt a more flexed posture at all joint levels in comparison with the control group. A significant difference in the mean ratio was found between groups, showing an asymmetric weight distribution in patients with knee OA. A significant decrease in the COP range in the anterior-posterior direction was also observed in the group of patients. Only small associations were observed between postural impairments and clinical outcomes. This study brings new insights regarding the postural behavior of patients with severe knee OA during a quiet standing task. The results confirm the multi-joint asymmetric posture adopted by this population. Copyright © 2014 Elsevier B.V. All rights reserved.

Footwear for the neuropathic patient: offloading and stability.

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van Deursen, Robert

2008-01-01

Diabetic neuropathy is related to plantar ulceration through a variety of factors of which increased plantar pressures and loss of protective sensation are the most important. Loss of sensation in the lower limbs is also related to postural instability and an increased risk of falling. Ankle and foot proprioception play an important role in postural control and this sensory function is also affected by neuropathy. It is conceivable that footwear, orthotics, casts and braces used for treatment or prevention of plantar ulceration through offloading of the injured or at-risk foot area can exacerbate the postural instability and risk of falling. This has, however, received very limited attention in the literature. There are studies that have demonstrated that footwear adjustments can influence balance and stability in healthy, elderly subjects. The adjustments made to footwear for the diabetic foot are generally more dramatic and, therefore, are expected to have a greater influence on postural stability. Furthermore, casts and braces tend to deviate even more from normal footwear. This may seriously interfere with normal gait and posture and, therefore, stability. So far the evidence suggests that patients wearing such devices demonstrate markedly reduced activity levels. This reduced activity could add to the effect of offloading. This could also be interpreted to indicate problems with stability. This presentation will review the different types of offloading interventions frequently used for ulcer treatment and prevention and will consider the mechanical effect of these interventions on stability.

Advantages and disadvantages of stiffness instructions when studying postural control.

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Bonnet, Cédrick T

2016-05-01

To understand the maintenance of upright stance, researchers try to discover the fundamental mechanisms and attentional resources devoted to postural control and eventually to the performance of other tasks (e.g., counting in the head). During their studies, some researchers require participants to stand as steady as possible and other simply ask participants to stand naturally. Surprisingly, a clear and direct explanation of the usefulness of the steadiness requirement seems to be lacking, both in experimental and methodological discussions. Hence, the objective of the present note was to provide advantages and disadvantages of this steadiness requirement in studies of postural control. The advantages may be to study fundamental postural control, to eliminate useless postural variability, to control spurious body motions and to control the participants' thoughts. As disadvantages, this steadiness requirement only leads to study postural control in unnatural upright stance, it changes the focus of attention (internal vs. external) and the nature of postural control (unconscious vs. conscious), it increases the difficulty of a supposedly easy control task and it eliminates or reduces the opportunity to record exploratory behaviors. When looking carefully at the four advantages of the steadiness requirement, one can believe that they are, in fact, more disadvantageous than advantageous. Overall therefore, this requirement seems illegitimate and it is proposed that researchers should not use it in the study of postural control. They may use this requirement only if they search to know the limit until which participants can consciously reduce their postural sway. Copyright © 2015 Elsevier B.V. All rights reserved.

Testing postural control among various osteoporotic patient groups: A literature review

NARCIS (Netherlands)

de Groot, M.H.; van der Jagt-Willems, H.; van Campen, J.P.C.M.; Lems, W.F.; Lamoth, C.J.

2012-01-01

Aim: Osteoporosis can cause vertebral fractures, which might lead to a flexed posture, impaired postural control and consequently increased fall risk. Therefore, the aim of the present review was to examine whether postural control of patients with osteoporosis, vertebral fractures, thoracic

Testing postural control among various osteoporotic patient groups : A literature review

NARCIS (Netherlands)

de Groot, Maartje H.; van der Jagt-Willems, Hanna C.; van Campen, Jos P. C. M.; Lems, Willem F.; Lamoth, Claudine J. C.

2012-01-01

Aim: Osteoporosis can cause vertebral fractures, which might lead to a flexed posture, impaired postural control and consequently increased fall risk. Therefore, the aim of the present review was to examine whether postural control of patients with osteoporosis, vertebral fractures, thoracic

Stress views in the radiography of scapholunate instability

International Nuclear Information System (INIS)

Ozcelik, Abdurrahman; Guenal, Izge; Koese, Nusret

2005-01-01

Aim: On the suspected carpal instabilities stress views are recommended but not often used. The present study evaluates the reliability of the dorsal and volar stress radiographs on patients with posttraumatic wrist pain. Patients and methods: Stress radiographs of the wrists were examined in 22 patients with chronic wrist pain and the results were compared with scaphoid shift test and standard and positional views. The stress examination consists of applying to the wrist dorsal and volar stresses on the hand. Results: Static scapholunate instability was diagnosed in 4 patients in whom 3 of them had positive scaphoid shift test sign as well. There were, however, 18 patients with dynamic scapholunate instability in whom the standard films were normal but dorsal stress radiography showed gap greater than 3 mm between the scaphoid and lunate. Conclusion: Stress tests may provide considerable information in the evaluation of a patient who has a painful wrist in whom routine and special views do not demonstrate scapholunate dissociation

Population Differences in Postural Response Strategy Associated with Exposure to a Novel Continuous Perturbation Stimuli: Would Dancers Have Better Balance on a Boat?

Directory of Open Access Journals (Sweden)

Carolyn A Duncan

Full Text Available Central or postural set theory suggests that the central nervous system uses short term, trial to trial adaptation associated with repeated exposure to a perturbation in order to improve postural responses and stability. It is not known if longer-term prior experiences requiring challenging balance control carryover as long-term adaptations that influence ability to react in response to novel stimuli. The purpose of this study was to determine if individuals who had long-term exposure to balance instability, such as those who train on specific skills that demand balance control, will have improved ability to adapt to complex continuous multidirectional perturbations. Healthy adults from three groups: 1 experienced maritime workers (n = 14, 2 novice individuals with no experience working in maritime environments (n = 12 and 3 individuals with training in dance (n = 13 participated in the study. All participants performed a stationary standing task while being exposed to five 6 degree of freedom motions designed to mimic the motions of a ship at sea. The balance reactions (change-in-support (CS event occurrences and characteristics were compared between groups. Results indicate dancers demonstrated significantly fewer CS events than novices during the first trial, but did not perform as well as those with offshore experience. Linear trend analyses revealed that short-term adaptation across all five trials was dependent on the nature of participant experience, with dancers achieving postural stability earlier than novices, but later than those with offshore experience. These results suggest that long term previous experiences also have a significant influence on the neural control of posture and balance in the development of compensatory responses.

Locomotor Adaptation Improves Balance Control, Multitasking Ability and Reduces the Metabolic Cost of Postural Instability

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Bloomberg, J. J.; Peters, B. T.; Mulavara, A. P.; Brady, R. A.; Batson, C. D.; Miller, C. A.; Ploutz-Snyder, R. J.; Guined, J. R.; Buxton, R. E.; Cohen, H. S.

2011-01-01

During exploration-class missions, sensorimotor disturbances may lead to disruption in the ability to ambulate and perform functional tasks during the initial introduction to a novel gravitational environment following a landing on a planetary surface. The overall goal of our current project is to develop a sensorimotor adaptability training program to facilitate rapid adaptation to these environments. We have developed a unique training system comprised of a treadmill placed on a motion-base facing a virtual visual scene. It provides an unstable walking surface combined with incongruent visual flow designed to enhance sensorimotor adaptability. Greater metabolic cost incurred during balance instability means more physical work is required during adaptation to new environments possibly affecting crewmembers? ability to perform mission critical tasks during early surface operations on planetary expeditions. The goal of this study was to characterize adaptation to a discordant sensory challenge across a number of performance modalities including locomotor stability, multi-tasking ability and metabolic cost. METHODS: Subjects (n=15) walked (4.0 km/h) on a treadmill for an 8 -minute baseline walking period followed by 20-minutes of walking (4.0 km/h) with support surface motion (0.3 Hz, sinusoidal lateral motion, peak amplitude 25.4 cm) provided by the treadmill/motion-base system. Stride frequency and auditory reaction time were collected as measures of locomotor stability and multi-tasking ability, respectively. Metabolic data (VO2) were collected via a portable metabolic gas analysis system. RESULTS: At the onset of lateral support surface motion, subj ects walking on our treadmill showed an increase in stride frequency and auditory reaction time indicating initial balance and multi-tasking disturbances. During the 20-minute adaptation period, balance control and multi-tasking performance improved. Similarly, throughout the 20-minute adaptation period, VO2 gradually

Body posture recognition and turning recording system for the care of bed bound patients.

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Hsiao, Rong-Shue; Mi, Zhenqiang; Yang, Bo-Ru; Kau, Lih-Jen; Bitew, Mekuanint Agegnehu; Li, Tzu-Yu

2015-01-01

This paper proposes body posture recognition and turning recording system for assisting the care of bed bound patients in nursing homes. The system continuously detects the patient's body posture and records the length of time for each body posture. If the patient remains in the same body posture long enough to develop pressure ulcers, the system notifies caregivers to change the patient's body posture. The objective of recording is to provide the log of body turning for querying of patients' family members. In order to accurately detect patient's body posture, we developed a novel pressure sensing pad which contains force sensing resistor sensors. Based on the proposed pressure sensing pad, we developed a bed posture recognition module which includes a bed posture recognition algorithm. The algorithm is based on fuzzy theory. The body posture recognition algorithm can detect the patient's bed posture whether it is right lateral decubitus, left lateral decubitus, or supine. The detected information of patient's body posture can be then transmitted to the server of healthcare center by the communication module to perform the functions of recording and notification. Experimental results showed that the average posture recognition accuracy for our proposed module is 92%.

Effect of different head-neck-jaw postures on cervicocephalic kinesthetic sense.

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Zafar, H; Alghadir, A H; Iqbal, Z A

2017-12-01

To investigate the effect of different induced head-neck-jaw postures on head-neck relocation error among healthy subjects. 30 healthy adult male subjects participated in this study. Cervicocephalic kinesthetic sense was measured while standing, habitual sitting, habitual sitting with clenched jaw and habitual sitting with forward head posture during right rotation, left rotation, flexion and extension using kinesthetic sensibility test. Head-neck relocation error was least while standing, followed by habitual sitting, habitual sitting with forward head posture and habitual sitting with jaw clenched. However, there was no significant difference in error between different tested postures during all the movements. To the best of our knowledge, this is the first study to see the effect of different induced head-neck-jaw postures on head-neck position sense among healthy subjects. Assuming a posture for a short duration of time doesn't affect head-neck relocation error in normal healthy subjects.

Influence of head posture on the visual acuity of children with nystagmus

Directory of Open Access Journals (Sweden)

Ana Carla Ramos Vieira da Costa

2014-01-01

Full Text Available Purpose: Evaluate the relationship between the postural alignment of the head and possible interference in the view of children. Methods: We evaluated 11 children between 2 and 7 years of age of both sexes, with the visually impaired, who had nystagmus and head lock position. The test Lea Grating Acuity Test® was used to collect measurements of visual acuity. This applied on two occasions: with and without postural alignment of the head. For reliability of the postural alignment of the head, the slopes were measured by Fisiologic® software. Results: The children had a poorer performance after physiological postural alignment. This poor performance is possible due to loss of position lock nystagmus to gain postural alignment, said to be ideal. Postural compensations were observed, and sharply increased eyestrain. Conclusion: The pursuit of traditional postural alignment affect the visual response of children with visual impairments.

Is postural control affected by expertise in alpine skiing?

OpenAIRE

Noe, F; Paillard, T

2005-01-01

Objectives: This study examined the postural performance of two groups of male skiers competing at different levels and the consequences on postural control of the suppression of visual afferences by eye closure.

Thoracic posture, shoulder muscle activation patterns and isokinetic ...