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Sample records for bipedal postural control

  1. Effect of expertise in shooting and Taekwondo on bipedal and unipedal postural control isolated or concurrent with a reaction-time task.

    Science.gov (United States)

    Negahban, Hossein; Aryan, Najmolhoda; Mazaheri, Masood; Norasteh, Ali Asghar; Sanjari, Mohammad Ali

    2013-06-01

    It was hypothesized that training in 'static balance' or 'dynamic balance' sports has differential effects on postural control and its attention demands during quiet standing. In order to test this hypothesis, two groups of female athletes practicing shooting, as a 'static balance' sport, and Taekwondo, as a 'dynamic balance' sport, and a control group of non-physically active females voluntarily participated in this study. Postural control was assessed during bipedal and unipedal stance with and without performing a Go/No-go reaction time task. Visual and/or support surface conditions were manipulated in bipedal and unipedal stances in order to modify postural difficulty. Mixed model analysis of variance was used to determine the effects of dual tasking on postural and cognitive performance. Similar pattern of results were found in bipedal and unipedal stances, with Taekwondo practitioners displaying larger sway, shooters displaying lower sway and non-athletes displaying sway characteristics intermediate to Taekwondo and shooting athletes. Larger effect was found in bipedal stance. Single to dual-task comparison of postural control showed no significant effect of mental task on sway velocity in shooters, indicating less cognitive effort invested in balance control during bipedal stance. We suggest that expertise in shooting has a more pronounced effect on decreased sway in static balance conditions. Furthermore, shooters invest less attention in postures that are more specific to their training, i.e. bipedal stance. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Origins of Bipedalism

    OpenAIRE

    Ko, Kwang Hyun

    2015-01-01

    The following manuscript reviews various theories of bipedalism and provides a holistic answer to human evolution. There are two questions regarding bipedalism: i) why were the earliest hominins partially bipedal? and ii) why did hominins become increasingly bipedal over time and replace their less bipedal ancestors? To answer these questions, the prominent theories in the field, such as the savanna-based theory, the postural feeding hypotheses, and the provisioning model, are collectively ex...

  3. Postural deficiencies in the static bipedal body alignment of students in a private university from Colombia

    Directory of Open Access Journals (Sweden)

    Sandra Yohana Quintero-Moya

    2016-06-01

    Full Text Available Introduction: Identifying the most prevalent postural deficiencies in a population allows the design interventions aimed at promoting adequate postural habits with a risk approach. Objective: To determine the postural deficiencies in the static bipedal body alignment and to explore gender differences in students in a private university from Bucaramanga, Colombia. Methodology: This was a cross-sectional study in a sample of 123 college students aged 18 to 29 years old. An expert on posture conducted the postural examination by analyzing seven printed photographs: one posterior, two right side, two left side and two anterior. We examined 94 deficiencies that were registered in the Body Alignment´s Systematic Observation Form (BASOF. Results: The main postural deficiencies in college women studied were head forward (Right side plane [RSP]: 85.3%; Left side plane [LSP]: 86.8%, shoulders protruded (RSP: 83.8%, LSP: 79.4%, left shoulder high (51.5%, decreased left torso-arm distance (50%, lumbar lordosis (RSP: 67.7%; LSP: 67.7%, anteverted pelvis (RSP: 67.7%, LSP: 67.7%, abdominal protrusion (RSP: 79.4; LSP: 79.5%, knee hyperextended (RSP: 50.0%, LSP: 62.2 % and left and right valgus Achilles with 51.5% and 60.3% respectively. While men had head forward (RSP: 92.7%, LSP: 92.7%, shoulders protruded (RSP: 76.4%, LSP: 81.8%, left shoulder high (54.6%, decreased right torso-arm distance (70.9%, abdominal protrusion (RSP: 60.0%, LSP: 60.0%, dorsal kyphosis (RSP: 60.0%, LSP: 60.0% and right tendon Achilles valgus (52.7%. Conclusion: There were gender specific deficiencies, which should be taken into account in future interventions.

  4. Contribution of each leg to the control of unperturbed bipedal stance in lower limb amputees: new insights using entropy.

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    Petra Hlavackova

    Full Text Available The present study was designed to assess the relative contribution of each leg to unperturbed bipedal posture in lower limb amputees. To achieve this goal, eight unilateral traumatic trans-femoral amputees (TFA were asked to stand as still as possible on a plantar pressure data acquisition system with their eyes closed. Four dependent variables were computed to describe the subject's postural behavior: (1 body weight distribution, (2 amplitude, (3 velocity and (4 regularity of centre of foot pressure (CoP trajectories under the amputated (A leg and the non-amputated (NA leg. Results showed a larger body weight distribution applied to the NA leg than to the A leg and a more regular CoP profiles (lower sample entropy values with greater amplitude and velocity under the NA leg than under the A leg. Taken together, these findings suggest that the NA leg and the A leg do not equally contribute to the control of unperturbed bipedal posture in TFA. The observation that TFA do actively control unperturbed bipedal posture with their NA leg could be viewed as an adaptive process to the loss of the lower leg afferents and efferents because of the unilateral lower-limb amputation. From a methodological point of view, these results demonstrate the suitability of computing bilateral CoP trajectories regularity for the assessment of lateralized postural control under pathological conditions.

  5. Origins of Bipedalism

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    Kwang Hyun Ko

    2015-12-01

    Full Text Available ABSTRACT This article aimed to review various theories of bipedalism and provide a holistic answer to human evolution. There have been two questions regarding bipedalism: i why were the earliest hominins partially bipedal?, and ii why did hominins become increasingly bipedal over the time and replaced their less bipedal ancestors? To answer these questions, the prominent theories in the field, such as the savanna-based theory, the postural feeding hypotheses, and the provisioning model, are collectively examined. Because biological evolution is not a simple causation; there may be multiple answers to the evolution of bipedalism. The postural feeding hypothesis (reaching for food/balancing provides an explanation for the partial bipedalism of the earliest hominins. The savannah-based theory describes how the largely bipedal hominins that started to settle on the ground became increasingly bipedal. The provisioning model (food-gathering/monogamy explains questions arising after the postural feeding hypothesis and before the savannah theory in an evolutionary timeline. Indeed, there are no straight lines between the theories, and multiple forces could have pushed the evolution of bipedalism at different points. Finally, the arboreal hominins that possessed ambiguous traits of bipedalism were eliminated through the choice and selection. Using the biological analogy of the okapi and giraffe, efforts were put to explain how one of the branches (Homo became increasingly bipedal, while the other (Pan adapted to locomotion for forest life by narrowing the anatomical/biological focus in evolution.

  6. Control strategy for energy-efficient bipedal walking with variable leg stiffness

    NARCIS (Netherlands)

    Visser, L.C.; Stramigioli, Stefano; Carloni, Raffaella

    In this work, we propose a hybrid model for a bipedal walker with controlled variable leg stiffness, and a control strategy for stable gait control. The control reference is a passive gait of the limit-case bipedal spring-loaded inverted pendulum model with massless feet, ensuring that the gait is

  7. Sensor Data Fusion for Body State Estimation in a Bipedal Robot and Its Feedback Control Application for Stable Walking

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    Ching-Pei Chen

    2015-02-01

    Full Text Available We report on a sensor data fusion algorithm via an extended Kalman filter for estimating the spatial motion of a bipedal robot. Through fusing the sensory information from joint encoders, a 6-axis inertial measurement unit and a 2-axis inclinometer, the robot’s body state at a specific fixed position can be yielded. This position is also equal to the CoM when the robot is in the standing posture suggested by the detailed CAD model of the robot. In addition, this body state is further utilized to provide sensory information for feedback control on a bipedal robot with walking gait. The overall control strategy includes the proposed body state estimator as well as the damping controller, which regulates the body position state of the robot in real-time based on instant and historical position tracking errors. Moreover, a posture corrector for reducing unwanted torque during motion is addressed. The body state estimator and the feedback control structure are implemented in a child-size bipedal robot and the performance is experimentally evaluated.

  8. A simple bipedal model for studying control of gait termination.

    Science.gov (United States)

    Suzuki, Yasuyuki; Geyer, Hartmut

    2018-03-27

    We study the control of human gait termination with a simple bipedal locomotion model. Several control strategies have been proposed for gait termination. However, the relative importance of these strategies has not been evaluated in models of human gait. Here we extend the bipedal spring mass walking model in a least parameter fashion and study three explicit control strategies for gait termination, including the shortening of the final step, braking at the ankle, and extending the knee. Applying the strategies separately, we find that only braking at the ankle reduces the propulsive force enough to transition into quiet standing. In combination with the other two strategies, we observe that the range of control parameters suitable for gait termination increases, especially when the ankle control is applied intermittently by taking advantage of passive stabilizing dynamics. We further show the resulting model behavior is compatible with several experimental observations about the human center of mass dynamics and leg forces during gait termination, and discuss model improvements to correct mismatches. The proposed model may serve as a starting point for more advanced models that can provide a deeper understanding of human control strategies during gait termination.

  9. Bipedal tool use strengthens chimpanzee hand preferences

    DEFF Research Database (Denmark)

    Braccini, Stephanie; Lambeth, Susan; Schapiro, Steve

    2010-01-01

    The degree to which non-human primate behavior is lateralized, at either individual or population levels, remains controversial. We investigated the relationship between hand preference and posture during tool use in chimpanzees (Pan troglodytes) during bipedal tool use. We experimentally induced...... tool use in a supported bipedal posture, an unsupported bipedal posture, and a seated posture. Neither bipedal tool use nor these supported conditions have been previously evaluated in apes. The hypotheses tested were 1) bipedal posture will increase the strength of hand preference, and 2) a bipedal......, to either the right or left, were emphasized with increasing postural demands. This result has interesting implications for theories of the evolution of tool use and bipedalism, as the combination of bipedalism and tool use may have helped drive extreme lateralization in modern humans, but cannot alone...

  10. Using intelligent controller to enhance the walking stability of bipedal walking robot

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    Hsieh, Tsung-Che; Chang, Chia-Der

    2016-07-01

    This paper is to improve the stability issue of the bipedal walking robot. The study of robot's pivot joint constructs the driver system to control the implementation. First, a Proportion-Integral-Derivative (PID) controller is designed by which is used the concept of tuning parameter to achieve the stability of the system. Second, Fuzzy controller and tradition PID controller is used to maintain output. It improved original PID controller efficacy. Finally, Artificial Neuro-Fuzzy Inference System (ANFIS) is utilized which is made the controller to achieve self-studying and modify the effect which is completed by the intelligent controller. It improved bipedal robot's stability control of realization. The result is verified that the walking stability of the bipedal walking robot in Matlab/Simulink. The intelligent controller has achieved the desired position of motor joint and the target stability performance.

  11. A neural network with central pattern generators entrained by sensory feedback controls walking of a bipedal model.

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    Li, Wei; Szczecinski, Nicholas S; Quinn, Roger D

    2017-10-16

    A neuromechanical simulation of a planar, bipedal walking robot has been developed. It is constructed as a simplified, planar musculoskeletal model of the biomechanics of the human lower body. The controller consists of a dynamic neural network with central pattern generators (CPGs) entrained by force and movement sensory feedback to generate appropriate muscle forces for walking. The CPG model is a two-level architecture, which consists of separate rhythm generator and pattern formation networks. The biped model walks stably in the sagittal plane without inertial sensors or a centralized posture controller or a 'baby walker' to help overcome gravity. Its gait is similar to humans' and it walks at speeds from 0.850 m s -1 up to 1.289 m s -1 with leg length of 0.84 m. The model walks over small unknown steps (6% of leg length) and up and down 5° slopes without any additional higher level control actions.

  12. Controller design for a bipedal walking robot using variable stiffness actuators

    NARCIS (Netherlands)

    Ketelaar, J. G.; Visser, L. C.; Stramigioli, S.; Carloni, R.

    2013-01-01

    The bipedal spring-loaded inverted pendulum (SLIP) model captures characteristic properties of human locomotion, and it is therefore often used to study human-like walking. The extended variable spring-loaded inverted pendulum (V-SLIP) model provides a control input for gait stabilization and shows

  13. Sensorimotor posture control in the blind: superior ankle proprioceptive acuity does not compensate for vision loss.

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    Ozdemir, Recep A; Pourmoghaddam, Amir; Paloski, William H

    2013-09-01

    To better understand sensorimotor posture control differences between blind and sighted individuals, we examined the role of ankle joint proprioception and ankle muscle strength on postural control in healthy blind (n=13, 25-58 years) and age- and sex-matched sighted (n=15, 20-65 years) volunteers. We measured ankle joint proprioceptive acuity and isokinetic muscle strength in plantarflexion and dorsiflexion using an isokinetic dynamometer. We also assessed postural control performance during quiet bipedal stance with and without sudden postural perturbations, and during quiet unipedal stance. We found that while our blind subjects exhibited significantly better proprioceptive acuity than our sighted subjects their postural control performance was significantly poorer than that of the sighted group with eyes open, and no different from that of the sighted group with eyes closed suggesting that their superior proprioceptive acuity does not translate to improved balance control. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Vestibular humanoid postural control.

    Science.gov (United States)

    Mergner, Thomas; Schweigart, Georg; Fennell, Luminous

    2009-01-01

    Many of our motor activities require stabilization against external disturbances. This especially applies to biped stance since it is inherently unstable. Disturbance compensation is mainly reactive, depending on sensory inputs and real-time sensor fusion. In humans, the vestibular system plays a major role. When there is no visual space reference, vestibular-loss clearly impairs stance stability. Most humanoid robots do not use a vestibular system, but stabilize upright body posture by means of center of pressure (COP) control. We here suggest using in addition a vestibular sensor and present a biologically inspired vestibular sensor along with a human-inspired stance control mechanism. We proceed in two steps. First, in an introductory review part, we report on relevant human sensors and their role in stance control, focusing on own models of transmitter fusion in the vestibular sensor and sensor fusion in stance control. In a second, experimental part, the models are used to construct an artificial vestibular system and to embed it into the stance control of a humanoid. The robot's performance is investigated using tilts of the support surface. The results are compared to those of humans. Functional significance of the vestibular sensor is highlighted by comparing vestibular-able with vestibular-loss states in robot and humans. We show that a kinematic body-space sensory feedback (vestibular) is advantageous over a kinetic one (force cues) for dynamic body-space balancing. Our embodiment of human sensorimotor control principles into a robot is more than just bionics. It inspired our biological work (neurorobotics: 'learning by building', proof of principle, and more). We envisage a future clinical use in the form of hardware-in-the-loop simulations of neurological symptoms for improving diagnosis and therapy and designing medical assistive devices.

  15. Early Permian bipedal reptile.

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    Berman, D S; Reisz, R R; Scott, D; Henrici, A C; Sumida, S S; Martens, T

    2000-11-03

    A 290-million-year-old reptilian skeleton from the Lower Permian (Asselian) of Germany provides evidence of abilities for cursorial bipedal locomotion, employing a parasagittal digitigrade posture. The skeleton is of a small bolosaurid, Eudibamus cursoris, gen. et sp. nov. and confirms the widespread distribution of Bolosauridae across Laurasia during this early stage of amniote evolution. E. cursoris is the oldest known representative of Parareptilia, a major clade of reptiles.

  16. Neuromechanical Control for Dynamic Bipedal Walking with Reduced Impact Forces

    DEFF Research Database (Denmark)

    Widenka, Johannes; Xiong, Xiaofeng; Matthias Braun, Jan

    2016-01-01

    Human walking emerges from an intricate interaction of nervous and musculoskeletal systems. Inspired by this principle, we integrate neural control and muscle-like mechanisms to achieve neuromechanical control of the biped robot RunBot. As a result, the neuromechanical controller enables Run...

  17. Planning and Control of Stable Walking for a 3D Bipedal Robot

    Directory of Open Access Journals (Sweden)

    Ching-Long Shih

    2012-08-01

    Full Text Available This paper presents a time-invariant feedback controller that simultaneously regulates the ZMP (zero-moment point position and the joint configuration of a 3D biped in order to achieve an asymptotically, periodic walking gait for a 3D bipedal robot with feet. The cyclic walking gait is composed of a successive single-support phase and an impulsive impact with full plane-contact between the feet and the ground. The biped robot has 10 DOFs (degrees of freedom in the single-support phase and 10 actuators. In order to avoid the unexpected rotation of the supporting foot, the position of the ZMP in the horizontal plane has to be controlled. It is also desired that the feedback controller tracks a parameterized reference trajectory to achieve walking stability. We use the method of virtual constraints previously implemented for controlling point-feet bipedal robots to create a set of parameterized reference walking trajectories. By creating the hybrid zero dynamics, an orbital stability study with Poincaré map is evaluated in a reduced space. We then design a supplemental event-based feedback controller to enhance walking stability. The walking gait has an average walking speed of 0.76m/sec (or 0.72 body lengths per second in the simulation study.

  18. Sensor Data Fusion for Body State Estimation in a Bipedal Robot and Its Feedback Control Application for Stable Walking

    OpenAIRE

    Chen, Ching-Pei; Chen, Jing-Yi; Huang, Chun-Kai; Lu, Jau-Ching; Lin, Pei-Chun

    2015-01-01

    We report on a sensor data fusion algorithm via an extended Kalman filter for estimating the spatial motion of a bipedal robot. Through fusing the sensory information from joint encoders, a 6-axis inertial measurement unit and a 2-axis inclinometer, the robot’s body state at a specific fixed position can be yielded. This position is also equal to the CoM when the robot is in the standing posture suggested by the detailed CAD model of the robot. In addition, this body state is further utilized...

  19. Postural control in blind subjects.

    Science.gov (United States)

    Soares, Antonio Vinicius; Oliveira, Cláudia Silva Remor de; Knabben, Rodrigo José; Domenech, Susana Cristina; Borges Junior, Noe Gomes

    2011-12-01

    To analyze postural control in acquired and congenitally blind adults. A total of 40 visually impaired adults participated in the research, divided into 2 groups, 20 with acquired blindness and 20 with congenital blindness - 21 males and 19 females, mean age 35.8 ± 10.8. The Brazilian version of Berg Balance Scale and the motor domain of functional independence measure were utilized. On Berg Balance Scale the mean for acquired blindness was 54.0 ± 2.4 and 54.4 ± 2.5 for congenitally blind subjects; on functional independence measure the mean for acquired blind group was 87.1 ± 4.8 and 87.3 ± 2.3 for congenitally blind group. Based upon the scale used the results suggest the ability to control posture can be developed by compensatory mechanisms and it is not affected by visual loss in congenitally and acquired blindness.

  20. Postural control in blind subjects

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    Antonio Vinicius Soares

    2011-12-01

    Full Text Available Objective: To analyze postural control in acquired and congenitally blind adults. Methods: A total of 40 visually impaired adults participated in the research, divided into 2 groups, 20 with acquired blindness and 20 with congenital blindness - 21 males and 19 females, mean age 35.8 ± 10.8. The Brazilian version of Berg Balance Scale and the motor domain of functional independence measure were utilized. Results: On Berg Balance Scale the mean for acquired blindness was 54.0 ± 2.4 and 54.4 ± 2.5 for congenitally blind subjects; on functional independence measure the mean for acquired blind group was 87.1 ± 4.8 and 87.3 ± 2.3 for congenitally blind group. Conclusion: Based upon the scale used the results suggest the ability to control posture can be developed by compensatory mechanisms and it is not affected by visual loss in congenitally and acquired blindness.

  1. Sport Skill-Specific Expertise Biases Sensory Integration for Spatial Referencing and Postural Control.

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    Thalassinos, Michalis; Fotiadis, Giorgos; Arabatzi, Fotini; Isableu, Brice; Hatzitaki, Vassilia

    2017-09-15

    The authors asked how sport expertise modulates visual field dependence and sensory reweighting for controlling posture. Experienced soccer athletes, ballet dancers, and nonathletes performed (a) a Rod and Frame test and (b) a 100-s bipedal stance task during which vision and proprioception were successively or concurrently disrupted in 20-s blocks. Postural adaptation was assessed in the mean center of pressure displacement, root mean square of center of pressure velocity and ankle muscles integrated electromyography activity. Soccer athletes were more field dependent than were nonathletes. During standing, dancers were more destabilized by vibration and required more time to reweigh sensory information compared with the other 2 groups. These findings reveal a sport skill-specific bias in the reweighing of sensory inputs for spatial orientation and postural control.

  2. Human-In-The-Loop Control of a Bipedal Robot with Variable Levels of Autonomy

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    National Aeronautics and Space Administration — Bipedal robots have a growing presence in space exploration and industrial applications because they can more easily and safely perform complex tasks in environments...

  3. Effects of slackline training on postural control, jump performance, and myoelectrical activity in female basketball players

    DEFF Research Database (Denmark)

    Santos, Luis; Fernández-Río, Javier; Fernández-García, Benjamín

    2016-01-01

    The main goal of the study was to assess the effects of slackline training on the postural control system and jump performance of athletes. Twenty-five female basketball players were randomized into 2 groups: control (N 12) and experimental (N 13). The latter experienced a 6-week supervised......, slacklining may be a valid cross-training tool for female basketball players....... slackline training (3 sessions per week, 5-9 minutes per session). Participants underwent center of pressure (CoP) testing through three 10-second tasks (bipedal, left leg, and right leg support) over firm and compliant surfaces with eyes open. Several CoP parameters were assessed: length, area, length...

  4. Neural Computation Scheme of Compound Control: Tacit Learning for Bipedal Locomotion

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    Shimoda, Shingo; Kimura, Hidenori

    The growing need for controlling complex behaviors of versatile robots working in unpredictable environment has revealed the fundamental limitation of model-based control strategy that requires precise models of robots and environments before their operations. This difficulty is fundamental and has the same root with the well-known frame problem in artificial intelligence. It has been a central long standing issue in advanced robotics, as well as machine intelligence, to find a prospective clue to attack this fundamental difficulty. The general consensus shared by many leading researchers in the related field is that the body plays an important role in acquiring intelligence that can conquer unknowns. In particular, purposeful behaviors emerge during body-environment interactions with the help of an appropriately organized neural computational scheme that can exploit what the environment can afford. Along this line, we propose a new scheme of neural computation based on compound control which represents a typical feature of biological controls. This scheme is based on classical neuron models with local rules that can create macroscopic purposeful behaviors. This scheme is applied to a bipedal robot and generates the rhythm of walking without any model of robot dynamics and environments.

  5. Discrete-State-Based Vision Navigation Control Algorithm for One Bipedal Robot

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    Dunwen Wei

    2015-01-01

    Full Text Available Navigation with the specific objective can be defined by specifying desired timed trajectory. The concept of desired direction field is proposed to deal with such navigation problem. To lay down a principled discussion of the accuracy and efficiency of navigation algorithms, strictly quantitative definitions of tracking error, actuator effect, and time efficiency are established. In this paper, one vision navigation control method based on desired direction field is proposed. This proposed method uses discrete image sequences to form discrete state space, which is especially suitable for bipedal walking robots with single camera walking on a free-barrier plane surface to track the specific objective without overshoot. The shortest path method (SPM is proposed to design such direction field with the highest time efficiency. However, one improved control method called canonical piecewise-linear function (PLF is proposed. In order to restrain the noise disturbance from the camera sensor, the band width control method is presented to significantly decrease the error influence. The robustness and efficiency of the proposed algorithm are illustrated through a number of computer simulations considering the error from camera sensor. Simulation results show that the robustness and efficiency can be balanced by choosing the proper controlling value of band width.

  6. A mathematical model for incorporating biofeedback into human postural control

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    Ersal Tulga

    2013-02-01

    Full Text Available Abstract Background Biofeedback of body motion can serve as a balance aid and rehabilitation tool. To date, mathematical models considering the integration of biofeedback into postural control have represented this integration as a sensory addition and limited their application to a single degree-of-freedom representation of the body. This study has two objectives: 1 to develop a scalable method for incorporating biofeedback into postural control that is independent of the model’s degrees of freedom, how it handles sensory integration, and the modeling of its postural controller; and 2 to validate this new model using multidirectional perturbation experimental results. Methods Biofeedback was modeled as an additional torque to the postural controller torque. For validation, this biofeedback modeling approach was applied to a vibrotactile biofeedback device and incorporated into a two-link multibody model with full-state-feedback control that represents the dynamics of bipedal stance. Average response trajectories of body sway and center of pressure (COP to multidirectional surface perturbations of subjects with vestibular deficits were used for model parameterization and validation in multiple perturbation directions and for multiple display resolutions. The quality of fit was quantified using average error and cross-correlation values. Results The mean of the average errors across all tactor configurations and perturbations was 0.24° for body sway and 0.39 cm for COP. The mean of the cross-correlation value was 0.97 for both body sway and COP. Conclusions The biofeedback model developed in this study is capable of capturing experimental response trajectory shapes with low average errors and high cross-correlation values in both the anterior-posterior and medial-lateral directions for all perturbation directions and spatial resolution display configurations considered. The results validate that biofeedback can be modeled as an additional

  7. Is there an association between variables of postural control and strength in prepubertal children?

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    Granacher, Urs; Gollhofer, Albert

    2012-01-01

    The risk of sustaining falls and sports-related injuries is particularly high in children. Deficits in balance and muscle strength represent 2 important intrinsic fall and injury-risk factors. Therefore, the purpose of this study was to investigate the relationship between variables of static and dynamic postural control and isometric and dynamic muscle strength and to find out whether there is an association between measures of postural control and muscle strength in prepubertal children. Thirty children participated in this study (age 6.7 ± 0.5 years; body mass index 16.0 ± 1.8 kg·m(-2)). Biomechanic tests included the measurements of maximal isometric torque and rate of force development (RFD) of the plantar flexors on an isokinetic device, jumping power and height (countermovement jump [CMJ]) on a force plate, and the assessment of static and dynamic posture during bipedal stance on a balance platform. The significance level was set at p < 0.05. No significant associations were observed between variables of static and dynamic postural control. Significant positive correlations were detected between the RFD of the plantar flexors and CMJ height (r = 0.425, p < 0.01). No statistically significant associations were found between measures of postural control and muscle strength. The nonsignificant correlations between static and dynamic postural control and muscle strength imply that primarily dynamic measures of postural control should be incorporated in fall and injury-risk assessment and that postural control and muscle strength appear to be independent of each other and may have to be trained in a complementary manner for fall and injury-preventive purposes.

  8. 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.

  9. 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.

  10. The importance of postural control for feeding.

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    Redstone, Fran; West, Joyce F

    2004-01-01

    Children with cerebral palsy and other neurodisabilities often have decreased postural control that exacerbates their feeding/swallowing disorders. Correct postural alignment is important in the normal feeding/swallowing process. In the child with cerebral palsy, the alignment and stability of the oral structures for feeding/swallowing may be compromised by abnormal muscle tone and movement patterns. Effective oral functioning for feeding begins with attaining better head stability to improve jaw control. Head control is influenced by trunk alignment, which depends upon the stability of the pelvic area. Techniques such as therapeutic seating and oral control can enhance postural alignment and improve oral functioning for the safe intake of food.

  11. Foramen magnum position in bipedal mammals.

    Science.gov (United States)

    Russo, Gabrielle A; Kirk, E Christopher

    2013-11-01

    The anterior position of the human foramen magnum is often explained as an adaptation for maintaining balance of the head atop the cervical vertebral column during bipedalism and the assumption of orthograde trunk postures. Accordingly, the relative placement of the foramen magnum on the basicranium has been used to infer bipedal locomotion and hominin status for a number of Mio-Pliocene fossil taxa. Nonetheless, previous studies have struggled to validate the functional link between foramen magnum position and bipedal locomotion. Here, we test the hypothesis that an anteriorly positioned foramen magnum is related to bipedalism through a comparison of basicranial anatomy between bipeds and quadrupeds from three mammalian clades: marsupials, rodents and primates. Additionally, we examine whether strepsirrhine primates that habitually assume orthograde trunk postures exhibit more anteriorly positioned foramina magna compared with non-orthograde strepsirrhines. Our comparative data reveal that bipedal marsupials and rodents have foramina magna that are more anteriorly located than those of quadrupedal close relatives. The foramen magnum is also situated more anteriorly in orthograde strepsirrhines than in pronograde or antipronograde strepsirrhines. Among the primates sampled, humans exhibit the most anteriorly positioned foramina magna. The results of this analysis support the utility of foramen magnum position as an indicator of bipedal locomotion in fossil hominins. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Postural control in sitting children with cerebral palsy

    NARCIS (Netherlands)

    Brogren, E; Hadders-Algra, M; Forssberg, H

    Children with cerebral palsy (CP) display postural problems, largely interfering with daily life activities. Clarification of neural mechanisms controlling posture in these children could serve as a base for more successful intervention. Studies on postural adjustments following horizontal forward

  13. Relationship between body composition and postural control in prepubertal overweight/obese children: A cross-sectional study.

    Science.gov (United States)

    Villarrasa-Sapiña, Israel; Álvarez-Pitti, Julio; Cabeza-Ruiz, Ruth; Redón, Pau; Lurbe, Empar; García-Massó, Xavier

    2018-02-01

    Excess body weight during childhood causes reduced motor functionality and problems in postural control, a negative influence which has been reported in the literature. Nevertheless, no information regarding the effect of body composition on the postural control of overweight and obese children is available. The objective of this study was therefore to establish these relationships. A cross-sectional design was used to establish relationships between body composition and postural control variables obtained in bipedal eyes-open and eyes-closed conditions in twenty-two children. Centre of pressure signals were analysed in the temporal and frequency domains. Pearson correlations were applied to establish relationships between variables. Principal component analysis was applied to the body composition variables to avoid potential multicollinearity in the regression models. These principal components were used to perform a multiple linear regression analysis, from which regression models were obtained to predict postural control. Height and leg mass were the body composition variables that showed the highest correlation with postural control. Multiple regression models were also obtained and several of these models showed a higher correlation coefficient in predicting postural control than simple correlations. These models revealed that leg and trunk mass were good predictors of postural control. More equations were found in the eyes-open than eyes-closed condition. Body weight and height are negatively correlated with postural control. However, leg and trunk mass are better postural control predictors than arm or body mass. Finally, body composition variables are more useful in predicting postural control when the eyes are open. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Skeletal adaptations to bipedalism

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    Vasiljević Perica

    2014-01-01

    Full Text Available Bipedalism is the main characteristic of humans. During evolutin bipedalism emerged probably as an adaptation to a changing environment. Major changes in skeletal system included femur, pelvis, skull and spine. The significance of bipedal locomotion: Bipedalism freed the forelimbs for carrying objects, creation and usage of tools. In the upright position animals have a broader view of the environment and the early detection of predators is crucial for survival. Bipedal locomotion makes larger distances easier to pass, which is very important in the migration of hominids.

  15. Regularity of Center of Pressure Trajectories in Expert Gymnasts during Bipedal Closed-Eyes Quiet Standing

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    Brice Isableu

    2017-06-01

    Full Text Available We compared postural control of expert gymnasts (G to that of non-gymnasts (NG during bipedal closed-eyes quiet standing using conventional and nonlinear dynamical measures of center of foot pressure (COP trajectories. Earlier findings based on COP classical variables showed that gymnasts exhibited a better control of postural balance but only in demanding stances. We examined whether the effect of expertise in Gymnastic can be uncovered in less demanding stances, from the analysis of the dynamic patterns of COP trajectories. Three dependent variables were computed to describe the subject’s postural behavior: the variability of COP displacements (ACoP, the variability of the COP velocities (VCoP and the sample entropy of COP (SEnCoP to quantify COP regularity (i.e., predictability. Conventional analysis of COP trajectories showed that NG and G exhibited similar amount and control of postural sway, as indicated by similar ACoP and VCoP values observed in NG and G, respectively. These results suggest that the specialized balance training received by G may not transfer to less challenging balance conditions such as the bipedal eyes-closed stance condition used in the present experiment. Interestingly, nonlinear dynamical analysis of COP trajectories regarding COP regularity showed that G exhibited more irregular COP fluctuations relative to NG, as indicated by the higher SEnCoP values observed for the G than for the NG. The present results showed that a finer-grained analysis of the dynamic patterns of the COP displacements is required to uncover an effect of gymnastic expertise on postural control in nondemanding postural stance. The present findings shed light on the surplus value in the nonlinear dynamical analysis of COP trajectories to gain further insight into the mechanisms involved in the control of bipedal posture.

  16. PALMILHAS PROPRIOCEPTIVAS PARA O CONTROLE POSTURAL

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    Alessandra Madia Mantovani

    2010-12-01

    Full Text Available The postural control and balance depend of the sensory system and musculoskeletal biomechanics being the feet one of the main sensors of the sensory system. The aim were to evaluate postural control and plantar pressures before, during and after the use of proprioceptive insoles. Participated 15 subjects, age 19,62,1 years old, and body mass índex (BMI of 24,45,4 kg/m2. Postural assessment values have been measured the arrows on the spine curvature, followed by analysis of plantar pressures and measures for pedobarometricstabilometric for measuring of displacement of center of pressure before, during andafter the use of insoles. In the results we saw normal arrows post insole plantar pressureand stabilometry not statistically significant after its use. Conclued that after using these insole, was saw an adequate postural realignment, probably due to adequate muscle and posture tonedemonstrating the importance of assessing the captor podal for understanding postural disordens.

  17. Multi-muscle control during bipedal stance: an EMG–EMG analysis approach. Experimental Brain Research

    NARCIS (Netherlands)

    Danna-Dos-Santos, A.; Boonstra, T.W.; Degani, A.M.; Cardoso, V.S.; Magalhaes, A.T.; Mochizuki, L.

    2014-01-01

    Posture and postural reactions to mechanical perturbations require the harmonic modulation of the activity of multiple muscles. This precision can become suboptimal in the presence of neuromuscular disorders and result in higher fall risk and associated levels of comorbidity. This study was designed

  18. Bipedal locomotion: toward unified concepts in robotics and neuroscience.

    Science.gov (United States)

    Azevedo, Christine; Espiau, Bernard; Amblard, Bernard; Assaiante, Christine

    2007-02-01

    This review is the result of a joint reflection carried out by researchers in the fields of robotics and automatic control on the one hand and neuroscience on the other, both trying to answer the same question: what are the functional bases of bipedal locomotion and how can they be controlled? The originality of this work is to synthesize the two approaches in order to take advantage of the knowledge concerning the adaptability and reactivity performances of humans and of the rich tools and formal concepts available in biped robotics. Indeed, we claim that the theoretical framework of robotics can enhance our understanding of human postural control by formally expressing the experimental concepts used in neuroscience. Conversely, biological knowledge of human posture and gait can inspire biped robot design and control. Therefore, both neuroscientists and roboticists should find useful information in this paper.

  19. Postural trials: expertise in rhythmic gymnastics increases control in lateral directions.

    Science.gov (United States)

    Calavalle, A R; Sisti, D; Rocchi, M B L; Panebianco, R; Del Sal, M; Stocchi, V

    2008-11-01

    The first aim of this paper was to investigate if expertise in rhythmic gymnastics influences postural performance even in an easy non-specific task such as bipedal posture. Rhythmic gymnastics is a unique female sport which encompasses aspects of both artistic gymnastics and ballet and includes the use of a small apparatus (rope, hoop, ball, clubs and ribbon). Most previous studies have shown that expertise achieved by artistic gymnasts and dancers improves postural steadiness only in the situations for which those athletes are trained. Literature has not yet compared rhythmic gymnasts to other athletes in terms of their postural strategies. Hence, the study presented herein tested a group of high level rhythmic gymnasts and a group of female university students, trained in other sports, in the bipedal posture under eyes open and closed conditions. A force platform was used to record body sway. (1) Distance from the centre of sway, (2) lateral and (3) antero-posterior displacements were analyzed in time and frequency domains. Comparing the two groups, it was found that rhythmic gymnasts had better strategies than students in simple postural tasks, especially in lateral directions and in the period from 0.05 to 2 s. The most interesting finding in this study is that rhythmic gymnastics training seems to have a direct effect on the ability to maintain bipedal posture, which may confirm the "transfer" hypothesis of rhythmic gymnastics expertise to bipedal postural sway, especially in medio-lateral displacements. This finding has never been reported in previous studies on artistic gymnasts and ballet dancers. Furthermore, the present study confirmed the visual dependence of all the athletes, irrespective of their disciplines, in their postural trials.

  20. Robust balance shift control with posture optimization

    NARCIS (Netherlands)

    Kavafoglu, Z.; Kavafoglu, Ersan; Egges, J.

    2015-01-01

    In this paper we present a control framework which creates robust and natural balance shifting behaviours during standing. Given high-level features such as the position of the center of mass projection and the foot configurations, a kinematic posture satisfying these features is synthesized using

  1. Development of the Coordination between Posture and Manual Control

    Science.gov (United States)

    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…

  2. Postural control in women with breast hypertrophy

    Directory of Open Access Journals (Sweden)

    Alessandra Ferreira Barbosa

    2012-07-01

    Full Text Available OBJECTIVES: The consequences of breast hypertrophy have been described based on the alteration of body mass distribution, leading to an impact on psychological and physical aspects. The principles of motor control suggest that breast hypertrophy can lead to sensorimotor alterations and the impairment of body balance due to postural misalignment. The aim of this study is to evaluate the postural control of women with breast hypertrophy under different sensory information conditions. METHOD: This cross-sectional study included 14 women with breast hypertrophy and 14 without breast hypertrophy, and the mean ages of the groups were 39 ±15 years and 39±16 years, respectively. A force platform was used to assess the sensory systems that contribute to postural control: somatosensory, visual and vestibular. Four postural conditions were sequentially tested: eyes open and fixed platform, eyes closed and fixed platform, eyes open and mobile platform, and eyes closed and mobile platform. The data were processed, and variables related to the center of pressure were analyzed for each condition. The Kruskal-Wallis test was used to compare the conditions between the groups for the area of center of pressure displacement and the velocity of center of pressure displacement in the anterior-posterior and medial-lateral directions. The alpha level error was set at 0.05. RESULTS: Women with breast hypertrophy presented an area that was significantly higher for three out of four conditions and a higher velocity of center of pressure displacement in the anterior-posterior direction under two conditions: eyes open and mobile platform and eyes closed and mobile platform. CONCLUSIONS: Women with breast hypertrophy have altered postural control, which was demonstrated by the higher area and velocity of center of pressure displacement.

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

    African Journals Online (AJOL)

    Mona Mokhtar El Bardawil

    2013-04-18

    Apr 18, 2013 ... parts of the central nervous system (CNS), which consists of the spinal cord and the brain, take part in controlling posture.6. The automatic postural responses are the earliest functionally effective responses that mediate a person's active postural movements' control in response to external balance perturba-.

  4. Stability boundaries and lateral postural control in parkinson's disease.

    NARCIS (Netherlands)

    van Wegen, E. E.; van Emmerik, R. E.; Wagenaar, R. C.; Ellis, T.

    2001-01-01

    Postural instability is a major problem in patients with Parkinson's disease (PD). We examined balance control in PD by using center of pressure (CP) variability and time-to-contact to investigate boundary relevant postural control behavior under quiet stance leaning conditions. Postural orientation

  5. Balance and postural control in basketball players

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    Murilo Curtolo

    Full Text Available Abstract Introduction: Basketball is one of the most popular sports involving gestures and movements that require single-leg based support. Dorsiflexion range of motion (DROM, balance and postural control may influence the performance of this sport. Objective: To compare and correlate measures of balance, postural control and ankle DROM between amateur basketball athletes and non-athletes. Methods: Cross-sectional study, composed by 122 subjects allocated into one control group (CG = 61 and one basketball group (BG = 61. These groups were subdivided into two other groups by age: 12-14 years and 15-18 years. The participants were all tested for postural balance with the Star Excursion Balance Test (SEBT, postural control with the Step-down test and DROM with the Weight-bearing lunge test (WBLT. Between-groups differences were compared using repeated-measures multivariate analysis of variance. Normalized reaching distances were analyzed and correlated with the WBLT and Step-down test. Results: There was no difference in the scores of WBLT (P = .488 and Step-down test (P =. 916 between the groups. Scores for the anterior reach (P = .001 and total score of SEBT (P = .030 were higher in BG. The values for the posterolateral (P = .001 and posteromedial reach (P = .001 of SEBT were higher in BG at the age of 15-18. The correlation between the anterior reach of the SEBT and WBLT was significant in BG between 12-14 years (r = 0.578, P = .008, and in the CG between 15-18 years (r = 0.608, P=.001. Conclusion: The balance was better in the BG, although adolescents between 15-18 years have better balance control for the posteromedial and posterolateral reaches of the SEBT.

  6. State of the Art: Bipedal Robots for Lower Limb Rehabilitation

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    Xiong Yang

    2017-11-01

    Full Text Available The bipedal robot is one of the most attractive robots types given its similarity to the locomotion of human beings and its ability to assist people to walk during rehabilitation. This review summarizes the chronological historical development of bipedal robots and introduces some current popular bipedal robots age. Then, the basic theory-stability control and key technology-motion planning of bipedal robots are introduced and analyzed. Bipedal robots have a wide range of applications in the service, education, entertainment, and other industries. After that, we specifically discuss the applications of bipedal robots in lower limb rehabilitation, including wearable exoskeleton robots, rehabilitation equipment, soft exoskeleton robots, and unpowered exoskeleton robots, and their control methods. Lastly, the future development and the challenges in this field are discussed.

  7. Cognitively and socially induced stress affects postural control.

    Science.gov (United States)

    Doumas, Michail; Morsanyi, Kinga; Young, William R

    2018-01-01

    Postural control is an adaptive process that can be affected by many aspects of human behavior, including emotional contexts. The main emotional contexts that affect postural control are postural threat and passive viewing of aversive or threatening images, both of which produce a reduction in postural sway. The aim of the present study was to assess whether similar stress-related changes in postural sway can be observed using stress induced by social evaluative threat (SET) while performing arithmetic tasks. Twelve young adults performed an arithmetic and a postural control task separately, concurrently, and concurrently with added time pressure in the arithmetic task. In the final condition, participants were given negative feedback about their performance in the arithmetic task and performed it again while being observed (SET condition). Results showed that stress increased linearly with task demand. Postural sway and reaction times were not affected by the first two conditions; however, when time pressure was introduced, reaction times became faster and sway amplitude increased. Finally, introduction of SET caused the predicted reduction in postural sway and an increase in reaction times relative to the time pressure condition. Our results suggest that stress induced using a combination of arithmetic tasks and social evaluative threat leads to systematic changes in postural control. The paradigm developed in the present study would be very useful in assessing interactions between cognition, stress, and postural control in the context of postural instability and falls in older adults.

  8. A bipedal mammalian model for spinal cord injury research: The tammar wallaby [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Norman R. Saunders

    2017-06-01

    Full Text Available Background: Most animal studies of spinal cord injury are conducted in quadrupeds, usually rodents. It is unclear to what extent functional results from such studies can be translated to bipedal species such as humans because bipedal and quadrupedal locomotion involve very different patterns of spinal control of muscle coordination. Bipedalism requires upright trunk stability and coordinated postural muscle control; it has been suggested that peripheral sensory input is less important in humans than quadrupeds for recovery of locomotion following spinal injury. Methods: We used an Australian macropod marsupial, the tammar wallaby (Macropus eugenii, because tammars exhibit an upright trunk posture, human-like alternating hindlimb movement when swimming and bipedal over-ground locomotion. Regulation of their muscle movements is more similar to humans than quadrupeds. At different postnatal (P days (P7–60 tammars received a complete mid-thoracic spinal cord transection. Morphological repair, as well as functional use of hind limbs, was studied up to the time of their pouch exit. Results: Growth of axons across the lesion restored supraspinal innervation in animals injured up to 3 weeks of age but not in animals injured after 6 weeks of age. At initial pouch exit (P180, the young injured at P7-21 were able to hop on their hind limbs similar to age-matched controls and to swim albeit with a different stroke. Those animals injured at P40-45 appeared to be incapable of normal use of hind limbs even while still in the pouch. Conclusions: Data indicate that the characteristic over-ground locomotion of tammars provides a model in which regrowth of supraspinal connections across the site of injury can be studied in a bipedal animal. Forelimb weight-bearing motion and peripheral sensory input appear not to compensate for lack of hindlimb control, as occurs in quadrupeds. Tammars may be a more appropriate model for studies of therapeutic interventions

  9. Obesity Impact on the Attentional Cost for Controlling Posture

    Science.gov (United States)

    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

  10. Obesity impact on the attentional cost for controlling posture.

    Directory of Open Access Journals (Sweden)

    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.

  11. A Methodology for Investigating Adaptive Postural Control

    Science.gov (United States)

    McDonald, P. V.; Riccio, G. E.

    1999-01-01

    Our research on postural control and human-environment interactions provides an appropriate scientific foundation for understanding the skill of mass handling by astronauts in weightless conditions (e.g., extravehicular activity or EVA). We conducted an investigation of such skills in NASA's principal mass-handling simulator, the Precision Air-Bearing Floor, at the Johnson Space Center. We have studied skilled movement-body within a multidisciplinary context that draws on concepts and methods from biological and behavioral sciences (e.g., psychology, kinesiology and neurophysiology) as well as bioengineering. Our multidisciplinary research has led to the development of measures, for manual interactions between individuals and the substantial environment, that plausibly are observable by human sensory systems. We consider these methods to be the most important general contribution of our EVA investigation. We describe our perspective as control theoretic because it draws more on fundamental concepts about control systems in engineering than it does on working constructs from the subdisciplines of biomechanics and motor control in the bio-behavioral sciences. At the same time, we have attempted to identify the theoretical underpinnings of control-systems engineering that are most relevant to control by human beings. We believe that these underpinnings are implicit in the assumptions that cut across diverse methods in control-systems engineering, especially the various methods associated with "nonlinear control", "fuzzy control," and "adaptive control" in engineering. Our methods are based on these theoretical foundations rather than on the mathematical formalisms that are associated with particular methods in control-systems engineering. The most important aspects of the human-environment interaction in our investigation of mass handling are the functional consequences that body configuration and stability have for the pick up of information or the achievement of

  12. Self versus environment motion in postural control.

    Directory of Open Access Journals (Sweden)

    Kalpana Dokka

    2010-02-01

    Full Text Available To stabilize our position in space we use visual information as well as non-visual physical motion cues. However, visual cues can be ambiguous: visually perceived motion may be caused by self-movement, movement of the environment, or both. The nervous system must combine the ambiguous visual cues with noisy physical motion cues to resolve this ambiguity and control our body posture. Here we have developed a Bayesian model that formalizes how the nervous system could solve this problem. In this model, the nervous system combines the sensory cues to estimate the movement of the body. We analytically demonstrate that, as long as visual stimulation is fast in comparison to the uncertainty in our perception of body movement, the optimal strategy is to weight visually perceived movement velocities proportional to a power law. We find that this model accounts for the nonlinear influence of experimentally induced visual motion on human postural behavior both in our data and in previously published results.

  13. Eye Movements Affect Postural Control in Young and Older Females.

    Science.gov (United States)

    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.

  14. Eye movements affect postural control in young and older females

    Directory of Open Access Journals (Sweden)

    Neil Marshall Thomas

    2016-09-01

    Full Text Available 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 show 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.

  15. Tracking control of a planar five-link bipedal walking system with point contact, considering self-impact joint constraint by adaptive neural network method

    Directory of Open Access Journals (Sweden)

    Yousef Bazargan-Lari

    Full Text Available AbstractIn order to achieve the practical characteristics of natural bipedal walking, a key feature is to realize "the straight knee state of walking" during stance and swing motions. Considering a straight knee necessitates that the shank link of each leg not to undergo the rotation angles which are greater than that of the thigh link. For this purpose, various methods have been proposed; the joint self-impact constraint has been suggested for energy-efficient (natural bipedal walking while realizing the straight knee constraint.The prominent objective of this research is to present a model based control method for trajectory tracking of a normal human-like bipedal walking, by considering the joint self-impact constraint. To achieve this objective, the dynamical equations of motion of an unconstrained biped are taken, developed and then modified to consider the joint self-impact constraint at the knee joint.To control this complicated dynamical system, the available anthropometric normal gait cycle data are taken to generate the desired trajectories of the thigh and knee joints of the self-impact biped. Due to the existence of complex nonlinear terms in the dynamical governing equations of self-impact biped, the authors propose to design a nonlinear intelligent controller by taking advantage of the adaptive neural network control method, which neither requires the evaluation of inverse dynamical model nor the time consuming training process. According to the simulation results, the tracking control of the biped robot is accomplished well and the biped walking seems naturally, despite of involving complex nonlinear terms in the dynamical governing equations of the self-impact biped.

  16. Postural control during visual and kinesthetic motor imagery.

    Science.gov (United States)

    Grangeon, M; Guillot, A; Collet, C

    2011-03-01

    Despite the accumulating evidence supporting an interaction between cognitive functions and postural control, little is known about the selective impact of the mental representation of an action, i.e., motor imagery (MI) on postural control. As postural oscillations are reduced during a cognitive task of backward silent counting, a greater stability is also expected during MI compared to a no-task condition (standing). Twenty participants took part in this experiment, which aimed at providing evidence that MI may improve postural stability. They were requested to mentally imagine a movement while standing on a force-plate. Results showed a decrease in both path length and postural sway variability on the anterior-posterior and lateral axes during all dual-task sessions, as compared to the motionless condition. These postural adjustments might result from both central and peripheral processes, and/or increased muscle stiffness. Conversely, postural oscillation amplitude increased on the vertical axis during MI of three vertical jumps, hence suggesting that postural regulations remain task-related during MI. Finally, our data showed that kinesthetic and visual imagery differentially impacted the postural regulation.

  17. Controller design for a bipedal walking robot using variable stiffness actuators

    NARCIS (Netherlands)

    Ketekaar, J.G.; Visser, L.C.; Stramigioli, Stefano; Carloni, Raffaella

    The (SLIP) model captures characteristic properties of human locomotion, and it is therefore often used to study human- like walking. The extended variable spring-loaded inverted pendulum (V-SLIP) model provides a control input for gait stabilization and shows robust and energy-efficient walking

  18. Port-based control of a compass-gait bipedal robot

    NARCIS (Netherlands)

    Duindam, V.; Stramigioli, Stefano; Zítek, P.

    2005-01-01

    We examine the control problem of curve-tracking for fully-actuated mechanical systems, applied to walking robots. First, we discuss earlier results on curve-tracking using a change of coordinates to split the kinetic energy in a desired and an undesired part. Then, we apply and extend these results

  19. Port-Based Modeling and Control for Efficient Bipedal Walking Robots

    NARCIS (Netherlands)

    Duindam, V.

    2006-01-01

    Research on walking robots has shown that the process of walking, in itself, requires little energy. Indeed, many robots have been built that walk with high efficiency. General analysis and control tools for such efficient walkers, however, are lacking, and many results are based on engineering

  20. 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=knee OA to prevent 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

  1. Chronic Low Quality Sleep Impairs Postural Control in Healthy Adults.

    Directory of Open Access Journals (Sweden)

    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.

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

    OpenAIRE

    Andrade,Larissa Pires de; Rinaldi,Natália Madalena; Coelho,Flávia Gomes de Melo; Tanaka,Kátia; Stella,Florindo; Gobbi,Lilian Teresa Bucken

    2014-01-01

    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 gr...

  3. Postural control in chronic obstructive pulmonary disease: a systematic review

    Directory of Open Access Journals (Sweden)

    Porto EF

    2015-06-01

    Full Text Available EF Porto,1,2 AAM Castro,1,3 VGS Schmidt,4 HM Rabelo,4 C Kümpel,2 OA Nascimento,5 JR Jardim5 1Pulmonary Rehabilitation Center, Federal University of São Paulo, 2Adventist University, São Paulo, 3Federal University of Pampa, Rio Grande do Sul, 4Pulmonary Rehabilitation Center, Adventist University, 5Respiratory Diseases, Pulmonary Rehabilitation Center, Federal University of São Paulo, São Paulo, Brazil Abstract: Patients with chronic obstructive pulmonary disease (COPD fall frequently, although the risk of falls may seem less important than the respiratory consequences of the disease. Nevertheless, falls are associated to increased mortality, decreased independence and physical activity levels, and worsening of quality of life. The aims of this systematic review was to evaluate information in the literature with regard to whether impaired postural control is more prevalent in COPD patients than in healthy age-matched subjects, and to assess the main characteristics these patients present that contribute to impaired postural control.Methods: Five databases were searched with no dates or language limits. The MEDLINE, PubMed, EMBASE, Web of Science, and PEDro databases were searched using “balance”, “postural control”, and “COPD” as keywords. The search strategies were oriented and guided by a health science librarian and were performed on March 27, 2014. The studies included were those that evaluated postural control in COPD patients as their main outcome and scored more than five points on the PEDro scale. Studies supplied by the database search strategy were assessed independently by two blinded researchers.Results: A total of 484 manuscripts were found using the “balance in COPD or postural control in COPD” keywords. Forty-three manuscripts appeared more than once, and 397 did not evaluate postural control in COPD patients as the primary outcome. Thus, only 14 studies had postural control as their primary outcome. Our study

  4. Task, muscle and frequency dependent vestibular control of posture

    NARCIS (Netherlands)

    Forbes, P.A.; Siegmund, G.P.; Schouten, A.C.; Blouin, J.S.

    2015-01-01

    The vestibular system is crucial for postural control; however there are considerable differences in the task dependence and frequency response of vestibular reflexes in appendicular and axial muscles. For example, vestibular reflexes are only evoked in appendicular muscles when vestibular

  5. Analysis of Postural Control Adaptation During Galvanic and Vibratory Stimulation

    National Research Council Canada - National Science Library

    Fransson, P

    2001-01-01

    The objective for this study was to investigate whether the postural control adaptation during galvanic stimulation of the vestibular nerve were similar to that found during vibration stimulation to the calf muscles...

  6. Postural control deficits identify lingering post-concussion neurological deficits

    Directory of Open Access Journals (Sweden)

    Thomas A. Buckley

    2016-03-01

    Full Text Available Concussion, or mild traumatic brain injury, incidence rates have reached epidemic levels and impaired postural control is a cardinal symptom. The purpose of this review is to provide an overview of the linear and non-linear assessments of post-concussion postural control. The current acute evaluation for concussion utilizes the subjective balance error scoring system (BESS to assess postural control. While the sensitivity of the overall test battery is high, the sensitivity of the BESS is unacceptably low and, with repeat administration, is unable to accurately identify recovery. Sophisticated measures of postural control, utilizing traditional linear assessments, have identified impairments in postural control well beyond BESS recovery. Both assessments of quiet stance and gait have identified lingering impairments for at least 1 month post-concussion. Recently, the application of non-linear metrics to concussion recovery have begun to receive limited attention with the most commonly utilized metric being approximate entropy (ApEn. ApEn, most commonly in the medial-lateral plane, has successfully identified impaired postural control in the acute post-concussion timeframe even when linear assessments of instrumented measures are equivalent to healthy pre-injury values; unfortunately these studies have not gone beyond the acute phase of recovery. One study has identified lingering deficits in postural control, utilizing Shannon and Renyi entropy metrics, which persist at least through clinical recovery and return to participation. Finally, limited evidence from two studies suggest that individuals with a previous history of a single concussion, even months or years prior, may display altered ApEn metrics. Overall, non-linear metrics provide a fertile area for future study to further the understanding of postural control impairments acutely post-concussion and address the current challenge of sensitive identification of recovery.

  7. Otolith and Vertical Canal Contributions to Dynamic Postural Control

    Science.gov (United States)

    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.

  8. Attentional demand for regulating postural sway: the effect of expertise in gymnastics.

    Science.gov (United States)

    Vuillerme, Nicolas; Nougier, Vincent

    2004-03-15

    A dual-task paradigm was used to investigate whether the expertise in motor skills requiring a fine postural control can modify the attentional demand necessary for regulating postural sway. Seven expert gymnasts and seven experts in other non-gymnastic sports were asked to respond as rapidly as possible to an unpredictable auditory stimulus while maintaining stable seated and in three upright postures of increasing difficulty: bipedal, unipedal, and unipedal on an unstable support (i.e. a 7 cm thick foam surface). RT values were used as an index of the attentional demand necessary for performing the postural tasks. Results showed that the attentional demand necessary for regulating postural sway increased as the postural task increased in difficulty. Interestingly, this effect was smaller for the gymnasts during unipedal stance. These findings suggest a decreased dependency on attentional processes for regulating postural sway during unipedal stance in gymnasts with respect to non-gymnasts.

  9. Development of adaptive sensorimotor control in infant sitting posture.

    Science.gov (United States)

    Chen, Li-Chiou; Jeka, John; Clark, Jane E

    2016-03-01

    A reliable and adaptive relationship between action and perception is necessary for postural control. Our understanding of how this adaptive sensorimotor control develops during infancy is very limited. This study examines the dynamic visual-postural relationship during early development. Twenty healthy infants were divided into 4 developmental groups (each n=5): sitting onset, standing alone, walking onset, and 1-year post-walking. During the experiment, the infant sat independently in a virtual moving-room in which anterior-posterior oscillations of visual motion were presented using a sum-of-sines technique with five input frequencies (from 0.12 to 1.24 Hz). Infants were tested in five conditions that varied in the amplitude of visual motion (from 0 to 8.64 cm). Gain and phase responses of infants' postural sway were analyzed. Our results showed that infants, from a few months post-sitting to 1 year post-walking, were able to control their sitting posture in response to various frequency and amplitude properties of the visual motion. Infants showed an adult-like inverted-U pattern for the frequency response to visual inputs with the highest gain at 0.52 and 0.76 Hz. As the visual motion amplitude increased, the gain response decreased. For the phase response, an adult-like frequency-dependent pattern was observed in all amplitude conditions for the experienced walkers. Newly sitting infants, however, showed variable postural behavior and did not systemically respond to the visual stimulus. Our results suggest that visual-postural entrainment and sensory re-weighting are fundamental processes that are present after a few months post sitting. Sensorimotor refinement during early postural development may result from the interactions of improved self-motion control and enhanced perceptual abilities. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Decoding bipedal locomotion from the rat sensorimotor cortex

    Science.gov (United States)

    Rigosa, J.; Panarese, A.; Dominici, N.; Friedli, L.; van den Brand, R.; Carpaneto, J.; DiGiovanna, J.; Courtine, G.; Micera, S.

    2015-10-01

    Objective. Decoding forelimb movements from the firing activity of cortical neurons has been interfaced with robotic and prosthetic systems to replace lost upper limb functions in humans. Despite the potential of this approach to improve locomotion and facilitate gait rehabilitation, decoding lower limb movement from the motor cortex has received comparatively little attention. Here, we performed experiments to identify the type and amount of information that can be decoded from neuronal ensemble activity in the hindlimb area of the rat motor cortex during bipedal locomotor tasks. Approach. Rats were trained to stand, step on a treadmill, walk overground and climb staircases in a bipedal posture. To impose this gait, the rats were secured in a robotic interface that provided support against the direction of gravity and in the mediolateral direction, but behaved transparently in the forward direction. After completion of training, rats were chronically implanted with a micro-wire array spanning the left hindlimb motor cortex to record single and multi-unit activity, and bipolar electrodes into 10 muscles of the right hindlimb to monitor electromyographic signals. Whole-body kinematics, muscle activity, and neural signals were simultaneously recorded during execution of the trained tasks over multiple days of testing. Hindlimb kinematics, muscle activity, gait phases, and locomotor tasks were decoded using offline classification algorithms. Main results. We found that the stance and swing phases of gait and the locomotor tasks were detected with accuracies as robust as 90% in all rats. Decoded hindlimb kinematics and muscle activity exhibited a larger variability across rats and tasks. Significance. Our study shows that the rodent motor cortex contains useful information for lower limb neuroprosthetic development. However, brain-machine interfaces estimating gait phases or locomotor behaviors, instead of continuous variables such as limb joint positions or speeds

  11. Skeletal Muscle Pump Drives Control of Cardiovascular and Postural Systems

    Science.gov (United States)

    Verma, Ajay K.; Garg, Amanmeet; Xu, Da; Bruner, Michelle; Fazel-Rezai, Reza; Blaber, Andrew P.; Tavakolian, Kouhyar

    2017-03-01

    The causal interaction between cardio-postural-musculoskeletal systems is critical in maintaining postural stability under orthostatic challenge. The absence or reduction of such interactions could lead to fainting and falls often experienced by elderly individuals. The causal relationship between systolic blood pressure (SBP), calf electromyography (EMG), and resultant center of pressure (COPr) can quantify the behavior of cardio-postural control loop. Convergent cross mapping (CCM) is a non-linear approach to establish causality, thus, expected to decipher nonlinear causal cardio-postural-musculoskeletal interactions. Data were acquired simultaneously from young participants (25 ± 2 years, n = 18) during a 10-minute sit-to-stand test. In the young population, skeletal muscle pump was found to drive blood pressure control (EMG → SBP) as well as control the postural sway (EMG → COPr) through the significantly higher causal drive in the direction towards SBP and COPr. Furthermore, the effect of aging on muscle pump activation associated with blood pressure regulation was explored. Simultaneous EMG and SBP were acquired from elderly group (69 ± 4 years, n = 14). A significant (p = 0.002) decline in EMG → SBP causality was observed in the elderly group, compared to the young group. The results highlight the potential of causality to detect alteration in blood pressure regulation with age, thus, a potential clinical utility towards detection of fall proneness.

  12. Postural control in patients with anterior cruciate ligament injury

    OpenAIRE

    Borin, Gabriela; Masullo, Catia de Lourdes; Bonfim, Thatia Regina; Oliveira, Anamaria Siriani de; Paccola, Cleber Antônio Jansen; Barela, José Ângelo; Bevilaqua-Grossi, Débora

    2010-01-01

    A lesão do ligamento cruzado anterior (LCA) do joelho acarreta alterações somatosensoriais em função da perda de informações provenientes dos mecanorreceptores presentes no LCA. Esses receptores constituem importante fonte de informação sensorial, afetando o desempenho de vários atos motores, dentre os quais o controle postural. O estudo objetivou analisar o controle postural de indivíduos com joelhos normais e com lesão unilateral do LCA. Participaram 15 voluntários com lesão do LCA (grupo l...

  13. Effects of emotional videos on postural control in children.

    Science.gov (United States)

    Brandão, Arthur de Freitas; Palluel, Estelle; Olivier, Isabelle; Nougier, Vincent

    2016-03-01

    The link between emotions and postural control has been rather unexplored in children. The objective of the present study was to establish whether the projection of pleasant and unpleasant videos with similar arousal would lead to specific postural responses such as postural freezing, aversive or appetitive behaviours as a function of age. We hypothesized that postural sway would similarly increase with the viewing of high arousal videos in children and adults, whatever the emotional context. 40 children participated in the study and were divided into two groups of age: group 7-9 years (n=23; mean age=8 years ± 0.7) and group 10-12 years (n=17; mean age=11 years ± 0.7). 19 adults (mean age=25.8 years ± 4.4) also took part in the experiment. They viewed emotional videos while standing still on a force platform. Centre of foot pressure (CoP) displacements were analysed. Antero-posterior, medio-lateral mean speed and sway path length increased similarly with the viewing of high arousal movies in the younger, older children, and adults. Our findings suggest that the development of postural control is not influenced by the maturation of the emotional processing. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Influence of heading perception in the control of posture.

    Science.gov (United States)

    Piras, Alessandro; Raffi, Milena; Perazzolo, Monica; Squatrito, Salvatore

    2018-02-10

    The optic flow visual input directly influences the postural control. The aim of the present study was to examine the relationship between visually induced heading perception and postural stability, using optic flow stimulation. The dots were accelerated to simulate a heading direction to the left or to the right of the vertical midline. The participants were instructed to indicate the perceived optic flow direction by making a saccade to the simulated heading direction. We simultaneously acquired electromyographyc and center of pressure (COP) signals. We analysed the postural sway during three different epochs: (i) the first 500 ms after the stimulus onset, (ii) 500 ms before saccade onset, epoch in which the perception is achieved and, (iii) 500 ms after saccade onset. Participants exhibited a greater postural instability before the saccade, when the perception of heading was achieved, and the sway increased further after the saccade. These results indicate that the conscious representation of the self-motion affects the neural control of posture more than the mere visual motion, producing more instability when visual signals are contrasting with eye movements. It could be that part of these effects are due to the interactions between gaze shift and optic flow. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Effects of vision and lumbar posture on trunk neuromuscular control.

    Science.gov (United States)

    Maaswinkel, Erwin; van Drunen, Paul; Veeger, Dirk-Jan H E J; van Dieën, Jaap H

    2015-01-21

    The goal of this study was to determine the effects of vision and lumbar posture on trunk neuromuscular control. Torso perturbations were applied with a pushing device while the subjects were restrained at the pelvis in a kneeling-seated position. Torso kinematics and the muscle activity of the lumbar part of the M. Longissimus were recorded for 14 healthy subjects. Four conditions were included: a flexion, extension and neutral lumbar posture with eyes closed and the neutral posture with eyes open. Frequency response functions of the admittance and reflexes showed that there was no significant difference between the eyes open and eyes closed conditions, thereby confirming that vision does not play a role in the stabilization of the trunk during small-amplitude trunk perturbations. In contrast, manipulating posture did lead to significant differences. In particular, the flexed condition led to a lower admittance and lower reflex contribution compared to the neutral condition. Furthermore, the muscle pre-activation (prior to the onset of the perturbation) was significantly lower in the flexed posture compared to neutral. This confirms that flexing the lumbar spine increases the passive tissue stiffness and decreases the contribution of reflex activity to trunk control. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Effects of four days hiking on postural control.

    Directory of Open Access Journals (Sweden)

    Marcus Fraga Vieira

    Full Text Available Hiking is a demanding form of exercise that may cause delayed responses of the postural muscles and a loss of somatosensory information, particularly when repeatedly performed for several days. These effects may negatively influence the postural control of hikers. Therefore, the aim of this study was to investigate the effects of a four-day hike on postural control. Twenty-six adults of both sexes travelled 262 kilometers, stopping for lunch and resting in the early evening each day. Force platforms were used to collect center of pressure (COP data at 100 Hz for 70 seconds before hiking started and immediately after arriving at the rest station each day. The COP time course data were analyzed according to global stabilometric descriptors, spectral analysis and structural descriptors using sway density curve (SDC and stabilometric diffusion analysis (SDA. Significant increases were found for global variables in both the anterior-posterior and medial-lateral directions (COP sway area, COP total sway path, COP mean velocity, COP root mean square value and COP range. In the spectral analysis, only the 80% power frequency (F80 in the anterior-posterior direction showed a significant increase, reflecting the increase of the sway frequencies. The SDC revealed a significant increase in the mean distance between peaks (MD and a significant decrease in the mean peak amplitudes (MP, suggesting that a larger torque amplitude is required for stabilization and that the postural stability is reduced. The SDA revealed a decrease in the long-term slope (Hl and increases in the short-term (Ks and the long-term (Kl intercepts. We considered the likelihood that the presence of local and general fatigue, pain and related neuromuscular adaptations and somatosensory deficits may have contributed to these postural responses. Together, these results demonstrated that four days of hiking increased sway frequencies and deteriorated postural control in the standing

  17. Effects of Slackline Training on Postural Control, Jump Performance, and Myoelectrical Activity in Female Basketball Players.

    Science.gov (United States)

    Santos, Luis; Fernández-Río, Javier; Fernández-García, Benjamín; Jakobsen, Markus D; González-Gómez, Lucía; Suman, Oscar E

    2016-03-01

    The main goal of the study was to assess the effects of slackline training on the postural control system and jump performance of athletes. Twenty-five female basketball players were randomized into 2 groups: control (N = 12) and experimental (N = 13). The latter experienced a 6-week supervised slackline training (3 sessions per week, 5-9 minutes per session). Participants underwent center of pressure (CoP) testing through three 10-second tasks (bipedal, left leg, and right leg support) over firm and compliant surfaces with eyes open. Several CoP parameters were assessed: length, area, length/area, speed, Ymean, Xmean, deltaY, deltaX, RMS (root-mean-squared amplitude of the CoP), RMSY, and RMSX. Surface electromyography recordings were obtained too. Participants were also tested on jump performance, provided perceived exertion (6-20 Borg scale) and local muscle perceived exertion. Center of pressure parameters significantly differed before and after training only in the experimental group and only on the compliant surface (left leg: length, area, speed, deltaY, and deltaX; right leg: length, speed, Ymean, deltaY, and RMSY). Surface electromyography recordings were comparable before and after training in both groups. Performance on a countermovement jump test significantly improved only in the experimental group (effect side was 3.21 and 1.36 [flight time and jump height, respectively], which is described as a large effect). Mechanical power of the legs, as measured through the 30-second maximal performance jump test, did not improve in either group. The slackline training was rated as "somewhat hard" with the quadriceps, soleus, and gastrocnemius being rated as the most engaged muscles. Data indicate that slacklining requires activation of the main lower limb muscles. On conclusion, slacklining may be a valid cross-training tool for female basketball players.

  18. A method to model anticipatory postural control in driver braking events

    NARCIS (Netherlands)

    Osth, J.; Eliasson, E.; Happee, R.; Brolin, K.

    2014-01-01

    Human body models (HBMs) for vehicle occupant simulations have recently been extended with active muscles and postural control strategies. Feedback control has been used to model occupant responses to autonomous braking interventions. However, driver postural responses during driver initiated

  19. On the functional aspects of variability in postural control

    NARCIS (Netherlands)

    Van Emmerik, Richard E.A.; Van Wegen, Erwin E.H.

    2002-01-01

    Current research in nonlinear dynamics and chaos theory has challenged traditional perspectives that associate high variability with performance decrement and pathology. It is argued that variability can play a functional role in postural control and that reduction of variability is associated with

  20. Somatosensory shift of postural control in dizzy patients.

    Science.gov (United States)

    Okumura, Tomoko; Horii, Arata; Kitahara, Tadashi; Imai, Takao; Uno, Atsuhiko; Osaki, Yasuhiro; Inohara, Hidenori

    2015-09-01

    Postural control is dependent on the visual system in normal conditions. Shift from visual to somatosensory dependence in dizzy patients suggests that utilizing the stable visual references is recommended for the rehabilitation of dizzy patients. To investigate which of the visual or somatosensory system is mainly used for substitution of the impaired spatial orientation in dizzy patients. We recruited 189 consecutive patients with or without dizziness and vestibular dysfunction. Dizzy patients were divided into three groups: acute, episodic, and chronic dizziness. Vestibular function was assessed by caloric test, traditional head impulse test, and head shaking nystagmus. Visual or somatosensory dependence of spatial orientation was assessed by posturography on a solid surface or on foam in eyes open or closed condition. The foam ratio (posturography with/without foam) when eyes were closed was indicative of somatosensory dependence of postural control, whereas the Romberg ratio on foam showed visual dependence. (Romberg ratio on foam)/(foam ratio with eyes closed) was calculated and used as an index of the visual/somatosensory dependence of postural control. The visual/somatosensory ratio of postural control was significantly lower in dizzy patients as well as patients with vestibular dysfunction, however, no differences were found between acute, episodic, and chronic dizziness.

  1. Postural control during reaching in preterm children with cerebral palsy

    NARCIS (Netherlands)

    van der Heide, JC; Begeer, C; Fock, JM; Otten, Bert; Stremmelaar, E; van Eykern, LA; Hadders-Algra, M

    Postural control during reaching with the dominant arm was assessed in 58 preterm children with cerebral palsy (CP) aged 2 to 11 years, comprising 34 with spastic hemiplegia (17 males, 17 females) and 24 with bilateral spastic CP (bilateral CP; 15 male, 9 females). Assessments were made by multiple

  2. Task, muscle and frequency dependent vestibular control of posture

    Science.gov (United States)

    Forbes, Patrick A.; Siegmund, Gunter P.; Schouten, Alfred C.; Blouin, Jean-Sébastien

    2015-01-01

    The vestibular system is crucial for postural control; however there are considerable differences in the task dependence and frequency response of vestibular reflexes in appendicular and axial muscles. For example, vestibular reflexes are only evoked in appendicular muscles when vestibular information is relevant to postural control, while in neck muscles they are maintained regardless of the requirement to maintain head on trunk balance. Recent investigations have also shown that the bandwidth of vestibular input on neck muscles is much broader than appendicular muscles (up to a factor of 3). This result challenges the notion that vestibular reflexes only contribute to postural control across the behavioral and physiological frequency range of the vestibular organ (i.e., 0–20 Hz). In this review, we explore and integrate these task-, muscle- and frequency-related differences in the vestibular system’s contribution to posture, and propose that the human nervous system has adapted vestibular signals to match the mechanical properties of the system that each group of muscles controls. PMID:25620919

  3. Postural control of elderly: moving to predictable and unpredictable targets.

    NARCIS (Netherlands)

    Jongman, Vera; Lamoth, Claudine J C; van Keeken, Helco; Caljouw, Simone R

    2012-01-01

    Impaired postural control with muscle weakness is an important predictor of falls within the elderly population.Particular daily activities that require weight shifting in order to be able to reach a specific target (a cup on a table) require continuous adjustments to keep the body's center of mass

  4. Postural Sway, Balance Confidence, and Fear of Falling in Women With Knee Osteoarthritis in Comparison to Matched Controls.

    Science.gov (United States)

    Taglietti, Marcelo; Dela Bela, Laís Faganello; Dias, Josilainne Marcelino; Pelegrinelli, Alexandre Roberto Marcondes; Nogueira, Jéssyca Fernandes; Batista Júnior, João Pedro; Carvalho, Rodrigo Gustavo da Silva; McVeigh, Joseph Gerard; Facci, Ligia Maria; Moura, Felipe Arruda; Cardoso, Jefferson Rosa

    2017-08-01

    Osteoarthritis (OA) is a chronic degenerative disease that commonly affects the knee joints. Individuals older than 65 years of age with knee OA have a greater risk of falls. However, there has been limited examination of the parameters of postural sway (increased time, speed, and postural sway area [center of pressure{CoP}]), and OA of the knee. The primary objective of this study was to determine whether the CoP variables discriminate between patients with knee OA and matched healthy volunteers, and to correlate the CoP variables with the Activities-Specific Balance Confidence Scale (ABC) and Falls Self-Efficacy Scale (FES). The secondary objective was to compare the CoP of older women with OA with a control group in bipedal support condition with eyes opened and closed. Cross-sectional study. University Biomechanics Laboratory. A total of 22 participants were divided into the following 2 groups of 11 participants each: an OA group (mean = 68 years, standard deviation = 7.4 years) and a control group (mean = 66 years, standard deviation = 4.4 years). Static postural balance was measured by a portable force platform. Data were collected in both visual conditions (eyes open and closed), in random order. Three attempts of 30 seconds were allowed for each participant on the force platform, with a 1-minute interval between attempts. Variables were the CoP total displacement of sway (TDS, in centimeters), anteroposterior amplitude displacement (APAD, in centimeters), medial-lateral amplitude displacement (MLAD, in centimeters), total mean velocity (TMV, in centimeters per second), and dispersion of the center of pressure (AREA, in centimeters squared). The postural sway analysis found statistically significant differences in the eyes open condition for the TDS (P = .020), APAD (P = .042), TMV (P = .010), and AREA (P = .045). In the discriminant analysis, none of the CoP variables were able to classify the groups (P = .15). The correlation analysis showed that only the

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

    Science.gov (United States)

    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 < 0.01). PD+FOG had impaired ability to voluntary lean forward, difficulties to stand on foam with eyes closed and reduced limits of stability compared to PD-FOG (p < 0.05). During quiet stance the average anterior-posterior COP position was significantly displaced towards posterior in PD+FOG in comparison to PD-FOG and HC (p < 0.05). The COP position correlated with severity of FOG (p < 0.01). PD+FOG and PD-FOG did not differ in average COP sway excursion, sway velocity, sway regularity and 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.

  6. Influence of Sensory Dependence on Postural Control

    Science.gov (United States)

    Santana, Patricia A.; Mulavara, Ajitkumar P.; Fiedler, Matthew J.

    2011-01-01

    The current project is part of an NSBRI funded project, "Development of Countermeasures to Aid Functional Egress from the Crew Exploration Vehicle Following Long-Duration Spaceflight." The development of this countermeasure is based on the use of imperceptible levels of electrical stimulation to the balance organs of the inner ear to assist and enhance the response of a person s sensorimotor function. These countermeasures could be used to increase an astronaut s re-adaptation rate to Earth s gravity following long-duration space flight. The focus of my project is to evaluate and examine the correlation of sensory preferences for vision and vestibular systems. Disruption of the sensorimotor functions following space flight affects posture, locomotion and spatial orientation tasks in astronauts. The Group Embedded Figures Test (GEFT), the Rod and Frame Test (RFT) and the Computerized Dynamic Posturography Test (CDP) are measurements used to examine subjects visual and vestibular sensory preferences. The analysis of data from these tasks will assist in relating the visual dependence measures recognized in the GEFT and RFT with vestibular dependence measures recognized in the stability measures obtained during CDP. Studying the impact of sensory dependence on the performance in varied tasks will help in the development of targeted countermeasures to help astronauts readapt to gravitational changes after long duration space flight.

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

    Directory of Open Access Journals (Sweden)

    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

  8. Assessment of Postural Control in Children with Cerebral Palsy: A Review

    Science.gov (United States)

    Pavao, Silvia Leticia; dos Santos, Adriana Neves; Woollacott, Marjorie Hines; Rocha, Nelci Adriana Cicuto Ferreira

    2013-01-01

    This paper aimed to review studies that assessed postural control (PC) in children with cerebral palsy (CP) and describe the methods used to investigate postural control in this population. It also intended to describe the performance of children with CP in postural control. An extensive database search was performed using the keywords: postural…

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

    Science.gov (United States)

    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.

  10. Practice of contemporary dance promotes stochastic postural control in aging.

    Science.gov (United States)

    Ferrufino, Lena; Bril, Blandine; Dietrich, Gilles; Nonaka, Tetsushi; Coubard, Olivier A

    2011-01-01

    As society ages and the frequency of falls increases, counteracting gait and posture decline is a challenging issue for countries of the developed world. Previous studies have shown that exercise and hazard management help to improve balance and/or decrease the risks for falling in normal aging. Motor activity based on motor-skill learning, particularly dance, can also benefit balance and decreases falls with age. Recent studies have suggested that older dancers have better balance, posture, or gait than non-dancers. Additionally, clinical or laboratory measures have shown improvements in some aspects of balance after dance interventions in elderly trainees. This study examined the impact of contemporary dance (CD) and of fall prevention (FP) programs on postural control of older adults. Posturography of quiet upright stance was performed in 41 participants aged 59-86 years before and after 4.4-month training in either CD or FP once a week. Though classical statistic scores failed to show any effect, dynamic analyses of the center-of-pressure displacements revealed significant changes after training. Specifically, practice of CD enhanced the critical time interval in diffusion analysis, and reduced recurrence and mathematical stability in recurrence quantification analysis, whereas practice of FP induced or tended to induce the reverse patterns. Such effects were obtained only in the eyes open condition. We suggest that CD training based on motor improvisation favored stochastic posture inducing plasticity in motor control, while FP training based on more stereotyped behaviors did not.

  11. Practice of contemporary dance promotes stochastic postural control in aging

    Directory of Open Access Journals (Sweden)

    Lena eFerrufino

    2011-12-01

    Full Text Available As society ages and the frequency of falls increases, counteracting gait and posture decline is a challenging issue for countries of the developed world. Previous studies have shown that exercise and hazard management help to improve balance and/or decrease the risks for falling in normal aging. Motor activity based on motor-skill learning, particularly dance, can also benefit balance and decreases falls with age. Recent studies have suggested that older dancers had better balance, posture, or gait than non-dancers. Additionally, clinical or laboratory measures have shown improvements in some aspects of balance after dance interventions in elderly trainees. This study examined the impact of contemporary dance (CD and of fall prevention (FP programs on postural control of older adults. Posturography of quiet upright stance was performed in forty-one participants aged 59-86 years before and after 4.4-month training in either CD or FP once a week. Though classical statistic scores failed to show any effect, dynamic analyses of the center-of-pressure displacements revealed significant changes after training. Specifically, practice of CD enhanced the critical time interval in diffusion analysis, and reduced recurrence and mathematical stability in recurrence quantification analysis, whereas practice of FP induced or tended to induce the reverse patterns. We suggest that CD training based on motor improvisation favored stochastic posture inducing plasticity in motor control, while FP training based on more stereotyped behaviors did not.

  12. Practice of Contemporary Dance Promotes Stochastic Postural Control in Aging

    Science.gov (United States)

    Ferrufino, Lena; Bril, Blandine; Dietrich, Gilles; Nonaka, Tetsushi; Coubard, Olivier A.

    2011-01-01

    As society ages and the frequency of falls increases, counteracting gait and posture decline is a challenging issue for countries of the developed world. Previous studies have shown that exercise and hazard management help to improve balance and/or decrease the risks for falling in normal aging. Motor activity based on motor-skill learning, particularly dance, can also benefit balance and decreases falls with age. Recent studies have suggested that older dancers have better balance, posture, or gait than non-dancers. Additionally, clinical or laboratory measures have shown improvements in some aspects of balance after dance interventions in elderly trainees. This study examined the impact of contemporary dance (CD) and of fall prevention (FP) programs on postural control of older adults. Posturography of quiet upright stance was performed in 41 participants aged 59–86 years before and after 4.4-month training in either CD or FP once a week. Though classical statistic scores failed to show any effect, dynamic analyses of the center-of-pressure displacements revealed significant changes after training. Specifically, practice of CD enhanced the critical time interval in diffusion analysis, and reduced recurrence and mathematical stability in recurrence quantification analysis, whereas practice of FP induced or tended to induce the reverse patterns. Such effects were obtained only in the eyes open condition. We suggest that CD training based on motor improvisation favored stochastic posture inducing plasticity in motor control, while FP training based on more stereotyped behaviors did not. PMID:22232582

  13. A Model-Based Approach to Attention and Sensory Integration in Postural Control of Older Adults

    OpenAIRE

    Mahboobin, Arash; Loughlin, Patrick J.; Redfern, Mark S.

    2007-01-01

    We conducted a dual-task experiment that involved information processing (IP) tasks concurrent with postural perturbations to explore the interaction between attention and sensory integration in postural control in young and older adults. A postural control model incorporating sensory integration and the influence of attention was fit to the data, from which parameters were then obtained to quantify the interference of attention on postural control. The model hypothesizes that the cognitive p...

  14. 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.

  15. 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

  16. Typical and atypical development of reaching and postural control in infancy

    NARCIS (Netherlands)

    Hadders-Algra, Mijna

    2013-01-01

    Successful reaching requires postural control, either by active regulation or by postural support. The present paper reviews literature on typical and atypical development of reaching and postural control during infancy. Typically, reaching movements end in grasping around 4 months of age.

  17. Walking Posture Control of Transmission Line Single Arm Inspection Robot

    Science.gov (United States)

    Yan, Yu; Liu, Xiaqing; Li, Jinliang; Ou, Yuexiong

    2017-07-01

    To control the walking posture according to transmission line single arm inspection robot, the robot is divided into normal walking and climbing walking two state, and gives the definition, then based on the state space method of state variable feedback and PD control method is used to control the two states, two kinds of control method of simulation by using Matlab, in the end, the two control methods proposed is validated in the actual circuit structures. The results show that, the proposed control method is rapid and effective, and can meet the needs of practical application.

  18. Characterizing the human postural control system using detrended fluctuation analysis

    Science.gov (United States)

    Teresa Blázquez, M.; Anguiano, Marta; de Saavedra, Fernando Arias; Lallena, Antonio M.; Carpena, Pedro

    2010-01-01

    Detrended fluctuation analysis is used to study the behaviour of the time series of the position of the center of pressure, output from the activity of a human postural control system. The results suggest that these trajectories present a crossover in their scaling properties from persistent (for high frequencies, short-range time scale) to anti-persistent (for low frequencies, long-range time scale) behaviours. The values of the scaling exponent found for the persistent parts of the trajectories are very similar for all the cases analysed. The similarity of the results obtained for the measurements done with both eyes open and both eyes closed indicate either that the visual system may be disregarded by the postural control system, while maintaining quiet standing, or that the control mechanisms associated with each type of information (visual, vestibular and somatosensory) cannot be disentangled with this technique.

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

    Science.gov (United States)

    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, psensory conditions [F5,295 = 5.55, pSensory 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 conditions, which was independent of clinical characteristics. Patients further demonstrated similar pattern and level of utilizing sensory information to maintain balance compared to the controls.

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

    Directory of Open Access Journals (Sweden)

    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.

  1. The effects of deuterium on static posture control

    Science.gov (United States)

    Layne, Charles S.

    1990-01-01

    A significant operational problem impacting upon the Space Shuttle program involves the astronaut's ability to safely egress from the Orbiter during an emergency situation. Following space flight, astronauts display significant movement problems. One variable which may contribute to increased movement ataxia is deuterium (D2O). Deuterium is present in low levels within the Orbiter's water supply but may accumulate to significant physiological levels during lengthy missions. Deuterium was linked to a number of negative physiological responses, including motion sickness, decreased metabolism, and slowing of neural conduction velocity. The effects of D2O on static postural control in response to a range of dosage levels were investigated. Nine sugjects were divided into three groups of three subjects each. The groups were divided into a low, medium, and a high D2O dosage group. The subjects static posture was assessed with the use of the EquiTest systems, a commercially available postural control evaluation system featuring movable force plates and a visual surround that can be servoed to the subject's sway. In addition to the force plate information, data about the degree of subject sway about the hips and shoulders was obtained. Additionally, surface electromyographic (EMG) data from the selected lower limb muscles were collected along with saliva samples used to determine the amount of deuterium enrichment following D2O ingestion. Two baseline testing sessions were performed using the EquiTest testing protocol prior to ingestion of the D2O. Thirty minutes after dosing, subjects again performed the tests. Two more post-dosing tests were run with an interest interval of one hour. Preliminary data anlaysis indicates that only subjects in the igh dose group displayed any significant static postural problems. Future analyses of the sway and EMG is expected to reveal significant variations in the subject's postural control strategy following D2O dosing. While

  2. Effect of textured insoles on postural control during static upright posture following lower limb muscle fatigue.

    Science.gov (United States)

    Palazzo, Francesco; Nardi, Alessandra; Tancredi, Virginia; Caronti, Alfio; Scalia Tomba, Gianpaolo; Lebone, Pietro; Padua, Elvira; Annino, Giuseppe

    2017-12-15

    The purpose of this study was to assess the effects of textured insoles on static upright posture before and after lower limb muscle fatigue. Textured insoles used contained small and non-deformable pebbles of various sizes that are able to stimulate a major number of mechanoreceptors. It was inserted inside footwear. Ten healthy young adults participated in the study (mean age 26.1 ± 3.07 years). They were asked to stand on a force platform in four sensory states: vision, no vision, with and without natural plantar stimulation. For each sensory state the subjects underwent a single 30-second trial in pre-fatigue and post-fatigue conditions. Muscle fatigue was induced by 60 seconds of continuous jumping. Centre of Pressure displacement, sway velocity, antero-posterior and medio- lateral sway velocity were measured using force platform. Textured insoles had a stabilizing effect on balance compared to control insoles. Textured insoles significantly reduced CoPDISP and VA/P levels in closed eyes pre-fatigue condition. Post-fatigue all postural parameters improved in both vision and no vision conditions. Textured insoles with rigid stimulation significantly improved CoPDISP, independently of vision, supplying relevant and complete sensory information and improving balance in fatigue conditions.

  3. Postural control in blind individuals: A systematic review.

    Science.gov (United States)

    Parreira, Rodolfo Borges; Grecco, Luanda André Collange; Oliveira, Claudia Santos

    2017-09-01

    Postural control (PC) requires the interaction of the three sensory systems for a good maintenance of the balance, and in blind people, lack of visual input can harm your PC. Thus the objective is to perform a literature review concerning role of sight in the maintenance of PC and the adaptation of brain structures when vision is absent. Studies were searched from Pubmed, and EMBASE that included individuals with congenital blindness. Articles studying person with acquired blindness or low vision was excluded from this review. 26 out of 322 articles were selected for review, and we found that 1) blind individuals exhibit PC deficits and that is compensated by the intensification of the remaining systems; 2) Neuroplastic adaptation occurs throughout the entire cerebral cortex; and 3) Sensorimotor stimulation and transcranial direct current stimulation seem to be a rehabilitation strategy. According to this review, the findings suggest that improved remaining sensations in the presence of adaptations and neuroplasticity, does not translate into better postural control performance. Regarding rehabilitation strategies, more studies are needed to show which therapeutic modality best contributes to postural control. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Postural control of mouth breathing school aged children regarding gender.

    Science.gov (United States)

    Roggia, Bruna; Correa, Bruna; Pranke, Gabriel Ivan; Facco, Rudi; Rossi, Angela Garcia

    2010-01-01

    Postural control of mouth breathing school aged children. To compare the posture and body balance of school aged children groups, with and without oral breathing considering the variable gender. The study was developed at a municipal school in the city of Santa Maria (Brazil) and received prior approval of the ethics committee of the University of Santa Maria. The study group (with oral breathing) and the control group (without oral breathing) were selected based on an anamnesis, age (between 8 and 12 years), assessment of the stomatognathic system and auditory evaluation. The final sample was composed by 51 children in the study group (20 female and 31 male) and 58 in the control group (34 female and 24 male). Both groups were submitted to a dynamic posturography (sensory organization test--SOT) and to a postural assessment in right and left lateral view. Regarding the female gender, a statistically significant difference was observed for the angle that evaluates head horizontal alignment; for the SOT III value and for all SOT mean values. As for the male gender, a significant numerical difference was observed for the knee angle, for the ankle angle, for the SOT III value, for the SOT IV value and for all SOT mean values. School aged children with oral breathing present postural alterations; females present head positing alterations and males present alterations in the position of the inferior limbs. The body balance of school aged children with oral breathing, of both genders, demonstrated to be altered when compared to children without oral breathing, especially in the presence of sensorial conflict.

  5. On the relative contribution of the paretic leg to the control of posture after stroke

    NARCIS (Netherlands)

    Roerdink, Melvyn; Geurts, Alexander C. H.; de Haart, Mirjam; Beek, Peter J.

    2009-01-01

    Reduced postural steadiness and asymmetry of weight bearing are characteristic for posture after stroke. To examine the relative contribution of each leg to postural control in a cohort of 33 stroke patients at 5 stages during 3 months of inpatient rehabilitation, while taking clinical scores of

  6. On the relative contribution of the paretic leg to the control of posture after stroke

    NARCIS (Netherlands)

    Roerdink, M.; Geurts, A.C.; de Haart, M.; Beek, P.J.

    2009-01-01

    Background: Reduced postural steadiness and asymmetry of weight bearing are characteristic for posture after stroke. Objective: To examine the relative contribution of each leg to postural control in a cohort of 33 stroke patients at 5 stages during 3 months of inpatient rehabilitation, while taking

  7. On the relative contribution of the paretic leg to the control of posture after stroke.

    NARCIS (Netherlands)

    Roerdink, M.; Geurts, A.C.H.; Haart, M. de; Beek, P.J.

    2009-01-01

    BACKGROUND: Reduced postural steadiness and asymmetry of weight bearing are characteristic for posture after stroke. OBJECTIVE: To examine the relative contribution of each leg to postural control in a cohort of 33 stroke patients at 5 stages during 3 months of inpatient rehabilitation, while taking

  8. Perinatal Development of the Motor Systems Involved in Postural Control

    Directory of Open Access Journals (Sweden)

    Laurent Vinay

    2005-01-01

    Full Text Available Motor behaviors of some species, such as the rat and the human baby, are quite immature at birth. Here we review recent data on some of the mechanisms underlying the postnatal maturation of posture in the rat, in particular the development of pathways descending from the brain stem and projecting onto the lumbar enlargement of the spinal cord. A short-lasting depletion in serotonin affects both posture and the excitability of motoneurons. Here we try to extrapolate to human development and suggest that the abnormalities in motor control observed in childhood—e.g, deficits in motor coordination—might have their roots in the prenatal period, in particular serotonin depletion due to exposure to several environmental and toxicological factors during pregnancy.

  9. ISway: a sensitive, valid and reliable measure of postural control

    Directory of Open Access Journals (Sweden)

    Mancini Martina

    2012-08-01

    Full Text Available Abstract Background Clinicians need a practical, objective test of postural control that is sensitive to mild neurological disease, shows experimental and clinical validity, and has good test-retest reliability. We developed an instrumented test of postural sway (ISway using a body-worn accelerometer to offer an objective and practical measure of postural control. Methods We conducted two separate studies with two groups of subjects. Study I: sensitivity and experimental concurrent validity. Thirteen subjects with early, untreated Parkinson’s disease (PD and 12 age-matched control subjects (CTR were tested in the laboratory, to compare sway from force-plate COP and inertial sensors. Study II: test-retest reliability and clinical concurrent validity. A different set of 17 early-to-moderate, treated PD (tested ON medication, and 17 age-matched CTR subjects were tested in the clinic to compare clinical balance tests with sway from inertial sensors. For reliability, the sensor was removed, subjects rested for 30 min, and the protocol was repeated. Thirteen sway measures (7 time-domain, 5 frequency-domain measures, and JERK were computed from the 2D time series acceleration (ACC data to determine the best metrics for a clinical balance test. Results Both center of pressure (COP and ACC measures differentiated sway between CTR and untreated PD. JERK and time-domain measures showed the best test-retest reliability (JERK ICC was 0.86 in PD and 0.87 in CTR; time-domain measures ICC ranged from 0.55 to 0.84 in PD and from 0.60 to 0.89 in CTR. JERK, all but one time-domain measure, and one frequency measure were significantly correlated with the clinical postural stability score (r ranged from 0.50 to 0.63, 0.01 Conclusions Based on these results, we recommend a subset of the most sensitive, reliable, and valid ISway measures to characterize posture control in PD: 1 JERK, 2 RMS amplitude and mean velocity from the time-domain measures, and 3 centroidal

  10. Influence of pain on postural control in women with neck pain

    Directory of Open Access Journals (Sweden)

    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.

  11. Virtual Balancing for Studying and Training Postural Control

    Directory of Open Access Journals (Sweden)

    Daniela Buettner

    2017-09-01

    Full Text Available Postural control during free stance has been frequently interpreted in terms of balancing an inverted pendulum. This even holds, if subjects do not balance their own, but an external body weight. We introduce here a virtual balancing apparatus, which produces torque in the ankle joint as a function of ankle angle resembling the gravity and inertial effects of free standing. As a first aim of this study, we systematically modified gravity, damping, and inertia to examine its effect on postural control beyond the physical constraints given in the real world. As a second aim, we compared virtual balancing to free stance to test its suitability for balance training in patients who are not able to balance their full body weight due to certain medical conditions. In a feasibility study, we analyzed postural control during free stance and virtual balancing in 15 healthy subjects. Postural control was characterized by spontaneous sway measures and measures of perturbed stance. During free stance, perturbations were induced by pseudorandom anterior-posterior tilts of the body support surface. In the virtual balancing task, we systematically varied the anterior-posterior position of the foot plate where the balancing forces are zero following a similar pseudorandom stimulus profile. We found that subjects' behavior during virtual balancing resembles free stance on a tilting platform. This specifically holds for the profile of body excursions as a function of stimulus frequencies. Moreover, non-linearity between stimulus and response amplitude is similar in free and virtual balancing. The overall larger stimulus induced body excursions together with an altered phase behavior between stimulus and response could be in part explained by the limited use of vestibular and visual feedback in our experimental setting. Varying gravity or damping significantly affected postural behavior. Inertia as an isolated factor had a mild effect on the response functions. We

  12. Reflex control of the spine and posture: a review of the literature from a chiropractic perspective

    Directory of Open Access Journals (Sweden)

    Schlappi Mark

    2005-08-01

    Full Text Available Abstract Objective This review details the anatomy and interactions of the postural and somatosensory reflexes. We attempt to identify the important role the nervous system plays in maintaining reflex control of the spine and posture. We also review, illustrate, and discuss how the human vertebral column develops, functions, and adapts to Earth's gravity in an upright position. We identify functional characteristics of the postural reflexes by reporting previous observations of subjects during periods of microgravity or weightlessness. Background Historically, chiropractic has centered around the concept that the nervous system controls and regulates all other bodily systems; and that disruption to normal nervous system function can contribute to a wide variety of common ailments. Surprisingly, the chiropractic literature has paid relatively little attention to the importance of neurological regulation of static upright human posture. With so much information available on how posture may affect health and function, we felt it important to review the neuroanatomical structures and pathways responsible for maintaining the spine and posture. Maintenance of static upright posture is regulated by the nervous system through the various postural reflexes. Hence, from a chiropractic standpoint, it is clinically beneficial to understand how the individual postural reflexes work, as it may explain some of the clinical presentations seen in chiropractic practice. Method We performed a manual search for available relevant textbooks, and a computer search of the MEDLINE, MANTIS, and Index to Chiropractic Literature databases from 1970 to present, using the following key words and phrases: "posture," "ocular," "vestibular," "cervical facet joint," "afferent," "vestibulocollic," "cervicocollic," "postural reflexes," "spaceflight," "microgravity," "weightlessness," "gravity," "posture," and "postural." Studies were selected if they specifically tested any or

  13. A New Standing Posture Detector to Enable People with Multiple Disabilities to Control Environmental Stimulation by Changing Their Standing Posture through a Commercial Wii Balance Board

    Science.gov (United States)

    Shih, Ching-Hsiang; Shih, Ching-Tien; Chiang, Ming-Shan

    2010-01-01

    This study assessed whether two persons with multiple disabilities would be able to control environmental stimulation using body swing (changing standing posture) and a Wii Balance Board with a newly developed standing posture detection program (i.e. a new software program turns a Wii Balance Board into a precise standing posture detector). The…

  14. Effect of Short Term Balance Training on Postural Stability in Ice Hockey Players

    Directory of Open Access Journals (Sweden)

    Pavol Čech

    2015-08-01

    Full Text Available Postural stability is one of latent factors affecting game performance of an individual to a certain extent. The presented study deals with monitoring changes of postural stability in ice hockey players after eight week’s balance training. The screened sample consisted of junior category ice hockey players divided into experimental (n = 8 and reference groups (n = 8. Postural stability was measured using a stabilographic method on the AMTI AccuSwayPLUS force platform. The level of postural stability was assessed in three tests, namely bipedal stance with and without sight control and bipedal stance with reduced proprioception using the parameters of 95% confidence ellipse, path of CoP and mean velocity of CoP. The level of monitored stability parameters did not indicate any significant differences between the groups in any of the tests at the level of significance α = 0.05. Comparing postural stability of the experimental group between pre-test and post-test showed significant differences in the test without sight control and the test with reduced proprioception in lCoP and vCoP parameters (Z = 2.1004; α ˂ 0.05. Regarding the reference group, no significant changes of the level of postural stability between the pre-test and post-test were found in any of the parameters (Z = 0.3652 to 1.8257; α ˃ 0.05.

  15. A Comparison of Postural Control Characteristics between Subjects with Kyphosis and Controls

    Directory of Open Access Journals (Sweden)

    A. Yalfani

    2010-01-01

    Full Text Available Introduction & Objective: It is known that postural control performance in upright standing position could be affected by abnormal posture alignment. Despite the fact that kyphosis is one of the most common spine abnormality, the effect of thoracic curve abnormality at sagittal plane on postural stability has received little attention to date. Therefore, the purpose of our study was to investigate the dynamic and static postural control among individuals with kyphosis in comparison with a control matched group.Materials & Methods: Nineteen males with increased normal thoracic kyphosis (> 40 degrees were randomly selected as kyphotic group. Eighteen controls matched for age, weight and height were selected to participate in the study. We measured the amount of kyphosis using flexible ruler as a noninvasive and reliable method. Dynamic and static postural stability were assessed using the biodex stability system and the balance error scoring system respectively. ANOVA with repeated measures followed by Tukey HSD test and independent t-test were employed for statistical analyses (p<0.05. Results: For dynamic postural assessment, the means of all stability indices were significantly higher in the kyphotic individuals than controls in the eyes-closed condition. With the platform in the most unstable position, kyphotic group were detected to have significantly poorer balance performance than controls in both eyes-open and eyes-closed conditions. For static balance evaluation, no difference was noted between both groups in stability performance during double and tandem stances. During the single-limb stance trials, the kyphotic group had poorer performance than controls while standing on the firm surface and foam surface (firm surface: p=0.044; foam surface: p=0.000.Conclusion: The findings suggest that postural control especially dynamic postural stability may be altered in individuals with increased thoracic kyphosis.

  16. 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.

  17. Bipedal locomotion in Tropidurus torquatus (Wied, 1820 and Liolaemus lutzae Mertens, 1938

    Directory of Open Access Journals (Sweden)

    O. Rocha-Barbosa

    Full Text Available Bipedalism has evolved on numerous occasions in phylogenetically diverse lizard families. In this paper we describe, for the first time, bipedal locomotion on South American lizards, the sand-dweller Liolaemus lutzae and the generalist Tropidurus torquatus. The lizards were videotaped running on a racetrack and the sequences were analyzed frame by frame. The body posture, as a whole, diverged a lot during bipedal locomotion between the two species, even though there was no difference regarding their sprint performance. The locomotor behavior of L. lutzae is, in general, more similar to the one observed on other sand-dweller lizards. Certain particularities are common, such as the digitigrade posture at footfall and throughout stance, trunk angles; and tail posture. In contrast, T. torquatus exhibited high trunk angles and dragged its tail, in a posture compared to basilisks. This body posture could be related to certain characteristics and obstacles of a microhabitat such as the one around lakes and streams (basilisks and the one with compact shrubby vegetation (T. torquatus.

  18. Linear and nonlinear analysis of postural control in frailty syndrome.

    Science.gov (United States)

    Vassimon-Barroso, Verena de; Catai, Aparecida Maria; Buto, Marcele Stephanie De Souza; Porta, Alberto; Takahashi, Anielle Cristhine De Medeiros

    Adaptive postural control can be impaired in the presence of frailty syndrome, given that this condition causes homeostatic dysregulation in physiological systems. To compare the center of pressure (CoP) displacements of non-frail, pre-frail, and frail elderly subjects in the standing position before and after postural transition of sitting and rising from a chair, using linear and nonlinear methods. Forty-two elderly subjects were divided into 3 groups: non-frail (n=15), pre-frail (n=15), and frail (n=12). The CoP displacements in the anteroposterior (AP) and mediolateral (ML) direction in the orthostatic position, 30s before and after sitting down and rising from a chair, were evaluated by means of linear measurements (root mean square (RMS), amplitude, and total average speed) and nonlinear measurements (corrected approximate entropy - CApEn), sample entropy (SampEn), and complexity index (CI) and its normalized versions. After sitting and rising, there was an increase in RMS in the ML direction in all groups and in the AP direction in the non-frail and frail groups. The frail group showed no reduction in entropy values in either direction, and the pre-frail group showed no reduction in the ML direction. The results of this study indicate that, in the presence of frailty syndrome, the organization of CoP displacements does not show less regularity after sitting and rising from a chair, reflecting a possible impairment of the integration of the systems involved in postural control. Copyright © 2017 Associação Brasileira de Pesquisa e Pós-Graduação em Fisioterapia. Publicado por Elsevier Editora Ltda. All rights reserved.

  19. Ankylosing Spondylitis and Posture Control: The Role of Visual Input

    Directory of Open Access Journals (Sweden)

    Alessandro Marco De Nunzio

    2015-01-01

    Full Text Available Objectives. To assess the motor control during quiet stance in patients with established ankylosing spondylitis (AS and to evaluate the effect of visual input on the maintenance of a quiet posture. Methods. 12 male AS patients (mean age 50.1 ± 13.2 years and 12 matched healthy subjects performed 2 sessions of 3 trials in quiet stance, with eyes open (EO and with eyes closed (EC on a baropodometric platform. The oscillation of the centre of feet pressure (CoP was acquired. Indices of stability and balance control were assessed by the sway path (SP of the CoP, the frequency bandwidth (FB1 that includes the 80% of the area under the amplitude spectrum, the mean amplitude of the peaks (MP of the sway density curve (SDC, and the mean distance (MD between 2 peaks of the SDC. Results. In severe AS patients, the MD between two peaks of the SDC and the SP of the center of feet pressure were significantly higher than controls during both EO and EC conditions. The MP was significantly reduced just on EC. Conclusions. Ankylosing spondylitis exerts negative effect on postural stability, not compensable by visual inputs. Our findings may be useful in the rehabilitative management of the increased risk of falling in AS.

  20. Does bipedality predict the group-level manual laterality in mammals?

    Science.gov (United States)

    Giljov, Andrey; Karenina, Karina; Malashichev, Yegor

    2012-01-01

    Factors determining patterns of laterality manifestation in mammals remain unclear. In primates, the upright posture favours the expression of manual laterality across species, but may have little influence within a species. Whether the bipedalism acts the same in non-primate mammals is unknown. Our recent findings in bipedal and quadrupedal marsupials suggested that differences in laterality pattern, as well as emergence of manual specialization in evolution might depend on species-specific body posture. Here, we evaluated the hypothesis that the postural characteristics are the key variable shaping the manual laterality expression across mammalian species. We studied forelimb preferences in a most bipedal marsupial, brush-tailed bettong, Bettongia penicillata in four different types of unimanual behavior. The significant left-forelimb preference at the group level was found in all behaviours studied. In unimanual feeding on non-living food, catching live prey and nest-material collecting, all or most subjects were lateralized, and among lateralized bettongs a significant majority displayed left-forelimb bias. Only in unimanual supporting of the body in the tripedal stance the distribution of lateralized and non-lateralized individuals did not differ from chance. Individual preferences were consistent across all types of behaviour. The direction or the strength of forelimb preferences were not affected by the animals' sex. Our findings support the hypothesis that the expression of manual laterality depends on the species-typical postural habit. The interspecies comparison illustrates that in marsupials the increase of bipedality corresponds with the increase of the degree of group-level forelimb preference in a species. Thus, bipedalism can predict pronounced manual laterality at both intra- and interspecific levels in mammals. We also conclude that quadrupedal position in biped species can slightly hinder the expression of manual laterality, but the evoked biped

  1. Does bipedality predict the group-level manual laterality in mammals?

    Directory of Open Access Journals (Sweden)

    Andrey Giljov

    Full Text Available BACKGROUND: Factors determining patterns of laterality manifestation in mammals remain unclear. In primates, the upright posture favours the expression of manual laterality across species, but may have little influence within a species. Whether the bipedalism acts the same in non-primate mammals is unknown. Our recent findings in bipedal and quadrupedal marsupials suggested that differences in laterality pattern, as well as emergence of manual specialization in evolution might depend on species-specific body posture. Here, we evaluated the hypothesis that the postural characteristics are the key variable shaping the manual laterality expression across mammalian species. METHODOLOGY/PRINCIPAL FINDINGS: We studied forelimb preferences in a most bipedal marsupial, brush-tailed bettong, Bettongia penicillata in four different types of unimanual behavior. The significant left-forelimb preference at the group level was found in all behaviours studied. In unimanual feeding on non-living food, catching live prey and nest-material collecting, all or most subjects were lateralized, and among lateralized bettongs a significant majority displayed left-forelimb bias. Only in unimanual supporting of the body in the tripedal stance the distribution of lateralized and non-lateralized individuals did not differ from chance. Individual preferences were consistent across all types of behaviour. The direction or the strength of forelimb preferences were not affected by the animals' sex. CONCLUSIONS/SIGNIFICANCE: Our findings support the hypothesis that the expression of manual laterality depends on the species-typical postural habit. The interspecies comparison illustrates that in marsupials the increase of bipedality corresponds with the increase of the degree of group-level forelimb preference in a species. Thus, bipedalism can predict pronounced manual laterality at both intra- and interspecific levels in mammals. We also conclude that quadrupedal position in

  2. Human bipedalism and body-mass index.

    Science.gov (United States)

    Yi, Su Do; Noh, Jae Dong; Minnhagen, Petter; Song, Mi-Young; Chon, Tae-Soo; Kim, Beom Jun

    2017-06-16

    Body-mass index, abbreviated as BMI and given by M/H 2 with the mass M and the height H, has been widely used as a useful proxy to measure a general health status of a human individual. We generalise BMI in the form of M/H p and pursue to answer the question of the value of p for populations of animal species including human. We compare values of p for several different datasets for human populations with the ones obtained for other animal populations of fish, whales, and land mammals. All animal populations but humans analyzed in our work are shown to have p ≈ 3 unanimously. In contrast, human populations are different: As young infants grow to become toddlers and keep growing, the sudden change of p is observed at about one year after birth. Infants younger than one year old exhibit significantly larger value of p than two, while children between one and five years old show p ≈ 2, sharply different from other animal species. The observation implies the importance of the upright posture of human individuals. We also propose a simple mechanical model for a human body and suggest that standing and walking upright should put a clear division between bipedal human (p ≈ 2) and other animals (p ≈ 3).

  3. Age-Related Interference between the Selection of Input-Output Modality Mappings and Postural Control

    OpenAIRE

    Stelzel, Christine; Schauenburg, Gesche; Rapp, Michael A.; Heinzel, Stephan; Granacher, Urs

    2017-01-01

    Age-related decline in executive functions and postural control due to degenerative processes in the central nervous system have been related to increased fall-risk in old age. Many studies have shown cognitive-postural dual-task interference in old adults, but research on the role of specific executive functions in this context has just begun. In this study, we addressed the question whether postural control is impaired depending on the coordination of concurrent response-selection processes...

  4. Clinical tools that measure sitting posture, seated postural control or functional abilities in children with motor impairments: a systematic review.

    Science.gov (United States)

    Field, Debra; Livingstone, Roslyn

    2013-11-01

    To identify and critically appraise clinical measurement tools used to assess sitting posture, seated postural control or functional abilities for children with motor impairment who are candidates for seating interventions. Searches were run in 15 electronic databases along with hand searching. The search included articles published in English to December 2011. Key terms included: posture, sitting, sitting posture, seated posture, seated postural control, sitting position, seating, wheelchair(s), outcome and assess(ment). The PRISMA statement was followed with inclusion criteria set a priori. Two reviewers independently screened titles, reviewed abstracts and identified full-text articles that met criteria. Data extraction included tool description and clinical utility. Two quality-rating scales were used to evaluate conduct of the studies and psychometric properties of the tools. Of the 497 titles found in the search, 29 full-text articles met the inclusion criteria and 19 tools were identified. Tools represented all components of the International Classification of Functioning, Disability and Health for Children and Youth (ICF-CY), with emphasis on body structure and function and activity components. Evidence supporting reliability and validity varied, with small sample sizes influencing quality ratings. Evidence of the tools' reliability was more prevalent than evidence of the tools' validity. Only four tools reported on responsiveness, an important consideration for evaluating change. Little information on clinical utility was provided. Although a number of tools are available, evidence supporting their use for seating interventions is limited, as is the evidence supporting the strength of their measurement properties. Few tools address participation, environmental factors or the child's and family's perspective.

  5. Center-of-pressure regularity as a marker for attentional investment in postural control: a comparison between sitting and standing postures

    NARCIS (Netherlands)

    Roerdink, M.; Hlavackova, P.; Vuillerme, N.

    2011-01-01

    Postural control is a highly automatized basic activity that requires limited attentional investments. These investments have been shown to increase from balancing experts to controls, and from controls to persons with impaired postural control. Such between-subject comparisons led to a proposed

  6. Design of a bipedal walking robot

    Science.gov (United States)

    Pratt, Jerry; Krupp, Ben

    2008-04-01

    We present the mechanical design of a bipedal walking robot named M2V2, as well as control strategies to be implemented for walking and balance recovery. M2V2 has 12 actuated degrees of freedom in the lower body: three at each hip, one at each knee, and two at each ankle. Each degree of freedom is powered by a force controllable Series Elastic Actuator. These actuators provide high force fidelity and low impedance, allowing for control techniques that exploit the natural dynamics of the robot. The walking and balance recovery controllers will use the concepts of Capture Points and the Capture Region in order to decide where to step. A Capture Point is a point on the ground in which a biped can step to in order to stop, and the Capture Region is the locus of such points.

  7. Motion Planning and Posture Control of the General 3-Trailer System

    OpenAIRE

    K. Raghuwaiya; B. Sharma; J. Vanualailai

    2014-01-01

    This paper presents a set of artificial potential field functions that improves upon, in general, the motion planning and posture control, with theoretically guaranteed point and posture stabilities, convergence and collision avoidance properties of the general3-trailer system in a priori known environment. We basically design and inject two new concepts; ghost walls and the distance optimization technique (DOT) to strengthen point and posture stabilities, in the sense of Lyapunov, of our dyn...

  8. Postural Control Deficits in Autism Spectrum Disorder: The Role of Sensory Integration

    Science.gov (United States)

    Doumas, Michail; McKenna, Roisin; Murphy, Blain

    2016-01-01

    We investigated the nature of sensory integration deficits in postural control of young adults with ASD. Postural control was assessed in a fixed environment, and in three environments in which sensory information about body sway from visual, proprioceptive or both channels was inaccurate. Furthermore, two levels of inaccurate information were…

  9. Precision control of an upright trunk posture in low back pain patients

    NARCIS (Netherlands)

    Willigenburg, N.W.; Kingma, I.; van Dieen, J.H.

    2012-01-01

    Background: Low back pain appears to be associated with impaired trunk postural control, which could be caused by proprioceptive deficits. We assessed control of trunk posture in conditions requiring high and low precision, with and without disturbance of proprioception by lumbar muscle vibration.

  10. Postural control is associated with cognition and fear of falling in patients with multiple sclerosis.

    Science.gov (United States)

    Perrochon, A; Holtzer, R; Laidet, M; Armand, S; Assal, F; Lalive, P H; Allali, G

    2017-04-01

    Multiple sclerosis (MS) is a chronic inflammatory and neurodegenerative disease affecting various neurological domains, such as postural control, cognition, fear of falling, depression-anxiety, and fatigue. This study examined the associations of cognitive functions, fear of falling, depression-anxiety, and fatigue with postural control in patients with MS. Postural control (sway velocity) of 63 patients with MS (age 39.0 ± 8.9 years; %female 57%; Expanded Disability Status Scale score median (interquartile range) 2.0 (1.5)) was recorded on two platforms at stable and unstable conditions. Cognition, fear of falling, depression-anxiety, and fatigue were evaluated by a comprehensive neuropsychological assessment. The associations between these domains and postural control have been measured by multivariable linear regression (adjusted for age, gender, disability, and education). In stable condition, only working memory was associated with postural control (p fear of falling were associated with postural control (p fear of falling were associated with postural control in MS patients, particularly in unstable condition. These findings highlight the association of cognitive functions and fear of falling with postural control in MS.

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

    African Journals Online (AJOL)

    The findings demonstrated that the trained ETG improved in their total Berg Balance Test (BBT) scores indicated that the training program successfully improved postural sway control for non-injured elderly females. Keywords: multisensory training, postural sway control, balance ability, visual input; vestibular input ...

  12. Aging causes a reorganization of cortical and spinal control of posture

    NARCIS (Netherlands)

    Papegaaij, Selma; Taube, Wolfgang; Baudry, Stephane; Otten, Egbert; Hortobagyi, Tibor

    2014-01-01

    Classical studies in animal preparations suggest a strong role for spinal control of posture. In humans 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,

  13. Assessing dynamic postural control during exergaming in older adults : A probabilistic approach

    NARCIS (Netherlands)

    Soancatl Aguilar, V.; Lamoth, C. J. C.; Maurits, N.M.; Roerdink, J. B. T. M.

    Digital games controlled by body movements (exergames) have been proposed as a way to improve postural control among older adults. Exergames are meant to be played at home in an unsupervised way. However, only few studies have investigated the effect of unsupervised home-exergaming on postural

  14. The Effect of Training on Postural Control in Dyslexic Children.

    Directory of Open Access Journals (Sweden)

    Nathalie Goulème

    Full Text Available The aim of this study was to explore whether a short postural training period could affect postural stability in dyslexic children. Postural performances were evaluated using Multitest Equilibre from Framiral. Posture was recorded in three different viewing conditions (eyes open fixating a target, eyes closed and eyes open with perturbed vision and in two different postural conditions (on stable and unstable support. Two groups of dyslexic children participated in the study, i.e. G1: 16 dyslexic participants (mean age 9.9 ± 0.3 years who performed short postural training and G2: 16 dyslexic participants of similar ages (mean age 9.1 ± 0.3 years who did not perform any short postural training. Findings showed that short postural training improved postural stability on unstable support surfaces with perturbed vision: indeed the surface, the mean velocity of CoP and the spectral power indices in both directions decreased significantly, and the cancelling time in the antero-posterior direction improved significantly. Such improvement could be due to brain plasticity, which allows better performance in sensory process and cerebellar integration.

  15. Temporal parameter change of human postural control ability during upright swing using recursive least square method

    Science.gov (United States)

    Goto, Akifumi; Ishida, Mizuri; Sagawa, Koichi

    2010-01-01

    The purpose of this study is to derive quantitative assessment indicators of the human postural control ability. An inverted pendulum is applied to standing human body and is controlled by ankle joint torque according to PD control method in sagittal plane. Torque control parameters (KP: proportional gain, KD: derivative gain) and pole placements of postural control system are estimated with time from inclination angle variation using fixed trace method as recursive least square method. Eight young healthy volunteers are participated in the experiment, in which volunteers are asked to incline forward as far as and as fast as possible 10 times over 10 [s] stationary intervals with their neck joint, hip joint and knee joint fixed, and then return to initial upright posture. The inclination angle is measured by an optical motion capture system. Three conditions are introduced to simulate unstable standing posture; 1) eyes-opened posture for healthy condition, 2) eyes-closed posture for visual impaired and 3) one-legged posture for lower-extremity muscle weakness. The estimated parameters Kp, KD and pole placements are applied to multiple comparison test among all stability conditions. The test results indicate that Kp, KD and real pole reflect effect of lower-extremity muscle weakness and KD also represents effect of visual impairment. It is suggested that the proposed method is valid for quantitative assessment of standing postural control ability.

  16. Multimodal Perception and Multicriterion Control of Nested Systems. 1; Coordination of Postural Control and Vehicular Control

    Science.gov (United States)

    Riccio, Gary E.; McDonald, P. Vernon

    1998-01-01

    The purpose of this report is to identify the essential characteristics of goal-directed whole-body motion. The report is organized into three major sections (Sections 2, 3, and 4). Section 2 reviews general themes from ecological psychology and control-systems engineering that are relevant to the perception and control of whole-body motion. These themes provide an organizational framework for analyzing the complex and interrelated phenomena that are the defining characteristics of whole-body motion. Section 3 of this report applies the organization framework from the first section to the problem of perception and control of aircraft motion. This is a familiar problem in control-systems engineering and ecological psychology. Section 4 examines an essential but generally neglected aspect of vehicular control: coordination of postural control and vehicular control. To facilitate presentation of this new idea, postural control and its coordination with vehicular control are analyzed in terms of conceptual categories that are familiar in the analysis of vehicular control.

  17. A model-based approach to attention and sensory integration in postural control of older adults.

    Science.gov (United States)

    Mahboobin, Arash; Loughlin, Patrick J; Redfern, Mark S

    2007-12-18

    We conducted a dual-task experiment that involved information processing (IP) tasks concurrent with postural perturbations to explore the interaction between attention and sensory integration in postural control in young and older adults. A postural control model incorporating sensory integration and the influence of attention was fit to the data, from which parameters were then obtained to quantify the interference of attention on postural control. The model hypothesizes that the cognitive processing and integration of sensory inputs for balance requires time, and that attention influences this processing time, as well as sensory selection by facilitating specific sensory channels. Performing a concurrent IP task had an overall effect on the time delay. Differences in the time delay of the postural control model were found for the older adults. The results suggest enhanced vulnerability of balance processes in older adults to interference from concurrent cognitive IP tasks.

  18. Effect of a Dynamic Seating Surface on Postural Control and Function in Children with Cerebral Palsy

    DEFF Research Database (Denmark)

    Meyer, Erna Rosenlund; Trew, Lisa

    Purpose: The purpose was to investigate if a seating system involving a dynamic material covering the seat back and base improves postural control, alignment and function in children with cerebral palsy and to investigate consequences of adapting The Seated Postural Control Measure to a target...... group with multifunctional disabilities. Relevance: Developing sitting systems for disabled persons is of great importance to avoid sitting problems, to increase the level of functioning and postural control which will have an impact on their daily living and activities. This project takes its starting...... Ethical Committee. Outcome measures were Seated Postural Control Measure (SPCM), which was modified to meet the children’s needs, was used to measure alignment and function. Force Sensitive Applications (FSA) on the seat surfaces was used to measure postural movements and interface pressure. All tests...

  19. 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; 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.

  20. 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

  1. 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

  2. Case Studies in Neuroscience: A dissociation of balance and posture demonstrated by camptocormia.

    Science.gov (United States)

    St George, R J; Gurfinkel, V S; Kraakevik, J; Nutt, J G; Horak, F B

    2018-01-01

    Upright stance in humans requires an intricate exchange between the neural mechanisms that control balance and those that control posture; however, the distinction between these control systems is hard to discern in healthy subjects. By studying balance and postural control of a participant with camptocormia - an involuntary flexion of the trunk during standing that resolves when supine - a divergence between balance and postural control was revealed. A kinematic and kinetic investigation of standing and walking showed a stereotyped flexion of the upper body by almost 80° over a few minutes, and yet the participant's ability to control center of mass within the base of support and to compensate for external perturbations remained intact. This unique case also revealed the involvement of automatic, tonic control of the paraspinal muscles during standing and the effects of attention. Although strength was reduced and MRI showed a reduction in muscle mass, there was sufficient strength to maintain an upright posture under voluntary control and when using geste antagoniste maneuvers or "sensory tricks" from visual, auditory, and haptic biofeedback. Dual tasks that either increased or decreased the attention given to postural alignment would decrease or increase the postural flexion, respectively. The custom-made "twister" device that measured axial resistance to slow passive rotation revealed abnormalities in axial muscle tone distribution during standing. The results suggest that the disorder in this case was due to a disruption in the automatic, tonic drive to the postural muscles and that myogenic changes were secondary. NEW & NOTEWORTHY By studying an idiopathic camptocormia case with a detailed biomechanical and sensorimotor approach, we have demonstrated unique insights into the neural control of human bipedalism 1) balance and postural control cannot be considered the same neural process, as there is a stereotyped abnormal flexed posture, without balance

  3. Postural Control in Children With Developmental Coordination Disorder

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    Reint H. Geuze

    2005-01-01

    Full Text Available The development of static balance is a basic characteristic of normal motor development. Most developmental motor tests include a measure of static balance. Children with Developmental Coordination Disorder (DCD often fail this item. This study reviews the balance problems of children with DCD. The general conclusion is drawn that under normal conditions static balance control is not a problem for children with DCD. Only in difficult, unattended, or novel situations such children seem to suffer from increased postural sway. These findings raise the question of what happens when balance is lost. The present study addresses the strength of correlation between the electromyography (EMG and force plate signals in one-leg stance over epochs of stable and unstable balance. Four groups of children were involved in the study: two age groups and a group of children with DCD and balance problems and their controls. The results show a clear involvement of tibialis anterior and peroneus muscles in the control of lateral balance in all conditions and groups. The group of children with DCD and balance problems,however, showed a weaker coupling between EMG and corrective force compared with control children, indicating non-optimal balance control. An evaluation of the existing data in terms of evidence of specific structural deficits associated with DCD provided converging evidence that suggests cerebellar involvement.

  4. Lower limb joint alignment and postural control in elderly women

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    Míriam Raquel Meira Mainenti

    2014-03-01

    The aim of this study was to test whether quiet stance body sway is associated with ankle and knee joint angles in elderly women. Joint angles were measured using a manual goniometer and body sway was assessed using a force platform and four postural tasks with a combination of feet positions and eye condition. The sample (N = 58 showed the following angle values: 102 (100-104 for the tibiotarsal joint, 176 (174-180 for the subtalar joint, 184 (181-187 for knee flexion-extension, and 13 (10-15 for the Q-angle. Q-angle was significantly correlated (p < 0.05 with center of foot pressure (CP displacement area (r = 0.36, anteroposterior (SDy, r = 0.34 and lateral (SDx, r = 0.31 CP standard deviation, and anteroposterior CP range (r = 0.38 during the closed base, eyes opened trial (CBEO. The valgus group showed statistically higher values than the normal and varus groups for SDy (0.56 vs. 0.52 and 0.46 mm; p = 0.02, SDx (0.55 vs. 0.49 and 0.36 mm; p = 0.02 and anteroposterior range (3.32 vs. 2.78 and 2.38 mm; p = 0.01, CBEO. The displacement velocity of the CP was significantly higher for the asymmetric than the symmetric Q-angle group (8.0 vs. 5.3 mm/s – closed base, eyes closed trial. Knee alignment was correlated with measures of body sway in elderly women, but ankle alignment showed no correlation. Knee morphology should be considered an associated factor for quiet stance postural control.

  5. Modeling, simulation and optimization of bipedal walking

    CERN Document Server

    Berns, Karsten

    2013-01-01

    The model-based investigation of motions of anthropomorphic systems is an important interdisciplinary research topic involving specialists from many fields such as Robotics, Biomechanics, Physiology, Orthopedics, Psychology, Neurosciences, Sports, Computer Graphics and Applied Mathematics. This book presents a study of basic locomotion forms such as walking and running is of particular interest due to the high demand on dynamic coordination, actuator efficiency and balance control. Mathematical models and numerical simulation and optimization techniques are explained, in combination with experimental data, which can help to better understand the basic underlying mechanisms of these motions and to improve them. Example topics treated in this book are Modeling techniques for anthropomorphic bipedal walking systems Optimized walking motions for different objective functions Identification of objective functions from measurements Simulation and optimization approaches for humanoid robots Biologically inspired con...

  6. Improving Postural Control in the Battement Tendu: One Teacher's Reflections and Somatic Exercises

    Science.gov (United States)

    Batson, Glenna

    2010-01-01

    The battement tendu is introduced early in dance training, remaining integral to a dancer's vocabulary. Although appearing relatively simple to execute, the tendu aesthetic takes years to master. One reason might be that efficient performance requires complex coordination of postural balance. Known as postural control, this coordination appears in…

  7. Aging and Posture Control: Changes in Sensory Organization and Muscular Coordination.

    Science.gov (United States)

    Woollacott, Marjorie H.; And Others

    1986-01-01

    Examined two aspects of balance control in the older adult: coordination of timing and amplitude of muscle responses to postural perturbations, and ability of the participant to reorganize sensory inputs and subsequently modify postural responses as a consequence of changing environmental conditions. (Author/ABB)

  8. Body segments decoupling in sitting: control of body posture from automatic chair adjustments

    NARCIS (Netherlands)

    van Geffen, P.; Molier, B.I.; Reenalda, Jasper; Veltink, Petrus H.; Koopman, Hubertus F.J.M.

    2008-01-01

    Background Individuals who cannot functionally reposition themselves adopt a passive body posture and suffer from physical discomfort in long-term sitting. To regulate body load and to prevent sitting related mobility problems, proper posture control is important. The inability to reposition

  9. The functional origin of dinosaur bipedalism: Cumulative evidence from bipedally inclined reptiles and disinclined mammals.

    Science.gov (United States)

    Persons, W Scott; Currie, Philip J

    2017-05-07

    Bipedalism is a trait basal to, and widespread among, dinosaurs. It has been previously argued that bipedalism arose in the ancestors of dinosaurs for the function of freeing the forelimbs to serve as predatory weapons. However, this argument does not explain why bipedalism was retained among numerous herbivorous groups of dinosaurs. We argue that bipedalism arose in the dinosaur line for the purpose of enhanced cursoriality. Modern facultatively bipedal lizards offer an analog for the first stages in the evolution of dinosaurian bipedalism. Many extant lizards assume a bipedal stance while attempting to flee predators at maximum speed. Bipedalism, when combined with a caudofemoralis musculature, has cursorial advantages because the caudofemoralis provides a greater source of propulsion to the hindlimbs than is generally available to the forelimbs. That cursorial advantage explains the relative abundance of cursorial facultative bipeds and obligate bipeds among fossil diapsids and the relative scarcity of either among mammals. Having lost their caudofemoralis in the Permian, perhaps in the context of adapting to a fossorial lifestyle, the mammalian line has been disinclined towards bipedalism, but, having never lost the caudofemoralis of their ancestors, cursorial avemetatarsalians (bird-line archosaurs) were naturally inclined towards bipedalism. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. 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.

  11. Oreopithecus was a bipedal ape after all: Evidence from the iliac cancellous architecture

    Science.gov (United States)

    Rook, Lorenzo; Bondioli, Luca; Köhler, Meike; Moyà-Solà, Salvador; Macchiarelli, Roberto

    1999-01-01

    Textural properties and functional morphology of the hip bone cancellous network of Oreopithecus bambolii, a 9- to 7-million-year-old Late Miocene hominoid from Italy, provide insights into the postural and locomotor behavior of this fossil ape. Digital image processing of calibrated hip bone radiographs reveals the occurrence of trabecular features, which, in humans and fossil hominids, are related to vertical support of the body weight, i.e., to bipedality. PMID:10411955

  12. The effect of trunk coordination exercise on dynamic postural control using a Core Noodle.

    Science.gov (United States)

    Miyake, Yuki; Nakamura, Shinichiro; Nakajima, Masaaki

    2014-10-01

    To investigate the influence of trunk coordination exercise on dynamic postural control relative to postural sway. The effects of trunk coordination exercises were examined using a Core Noodle for the postural sway in healthy students who were assigned to an exercise or control group. The independent variable was the extent of exposure to Core Noodle exercise, and the dependent variable was dynamic postural control. A stabilometer, which measures dynamic postural control, was used to evaluate the effectiveness of the exercises. In addition, center of gravity movements were assessed using a Gravicorder G-620 stabilometer in which the subject was asked to shift their center of gravity between 2 circles on a computer monitor. Pre- and post-intervention dynamic postural control was statistically evaluated between the exercise group and control group using the Mann-Whitney test. Finally, we investigated the application of these exercises for a stroke patient. For post-intervention, the envelop area, mean length of the pathways between 2 circles, and the number of circles were significantly higher in the exercise group. Trunk coordination exercise performed Core Noodle may be used to enhance the dynamic postural balance of healthy young adults, and it can also be adapted for stroke patients. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Importance of proprioceptive information for postural control in children with strabismus before and after strabismus surgery

    Directory of Open Access Journals (Sweden)

    Maria Pia Bucci

    2016-09-01

    Full Text Available The objective of this study is to examine the role of proprioception in postural balance in children with strabismus before and after realignment of their visual axes by eye surgery. Postural recordings were made with the TechnoConcept® force platform in twenty three children. Several conditions were studied, whether the subjects had both eyes open, or either the dominant or the non-dominant eye open, without and with foam pads of 4 mm underfoot. Recordings were performed before and after strabismus surgery. The surface area, the length and the mean speed of the center of pressure (CoP were analyzed. Before strabismus surgery, all children showed better stability with both eyes open with respect to the condition with the non dominant eye open; furthermore postural stability improved in the presence of foam pads. After surgery, all postural parameters (surface area, length and mean speed of CoP decreased significantly, especially in the non-dominant eye viewing condition. We suggest that strabismic children use mainly proprioceptive information in order to control their posture, but also visual inputs, which are important for obtaining a good postural stability. The alignment of the visual axes after surgery provides enhanced postural stability, suggesting, again the major role of visual inputs in the control of posture. Proprioceptive plasticity after strabismus surgery may allow better visual rehabilitation.

  14. POSTURAL CONTROL IN HEALTHY YOUNG ADULTS WITH AND WITHOUT CHRONIC MOTION SENSITIVITY

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    Alyahya D

    2016-02-01

    Full Text Available Background: Postural control requires complex processing of peripheral sensory inputs from the visual, somatosensory and vestibular systems. Motion sensitivity and decreased postural control are influenced by visual-vestibular conflicts.The purpose of this study was to measure the difference between the postural control of healthy adults with and without history of sub-clinical chronic motion sensitivity using a computerized dynamic posturography in a virtual reality environment. Sub-clinical chronic motion sensitivity was operationally defined as a history of avoiding activities causing dizziness, nausea, imbalance, and/or blurred vision without having a related medical diagnosis. Methods: Twenty healthy adults between 22 and 33 years of age participated in the study. Eleven subjects had sub-clinical chronic motion sensitivity and 9 subjects did not. Postural control was measured in both groups using the Bertec Balance Advantage-Dynamic Computerized Dynamic Posturography with Immersion Virtual Reality (CDP-IVR. The CDP-IVR reports an over-all equilibrium score based on subjects’ center of gravity displacement and postural sway while immersed in a virtual reality environment. Subjects were tested on stable (condition 1 and unstable (condition2 platform conditions. Results: There was no significant difference between the two groups in terms of mean age, height, weight, body mass index in kg/m2, postural control scores for conditions 2, and average (p>0.05. However, significant differences were observed in mean postural control for condition 1 between groups (p=0.03. Conclusions: Results of this study suggest that healthy young adults without chronic sub-clinical motion sensitivity have better postural control than those with chronic sub-clinical motion sensitivity. Further investigation is warranted to explore wider age ranges with larger samples sizes as well as intervention strategies to improve postural control.

  15. Changes in Postural Sway After a Single Global Postural Reeducation Session in University Students: A Randomized Controlled Trial.

    Science.gov (United States)

    Lozano-Quijada, Carlos; Poveda-Pagán, Emilio J; Segura-Heras, José V; Hernández-Sánchez, Sergio; Prieto-Castelló, María J

    2017-09-01

    The purpose of this study was to assess the effectiveness of a single session of global postural reeducation (GPR) in postural sway in young adult university students who use data visualization screens. A randomized controlled trial with 2 parallel groups was performed. Sixty-four subjects were randomized in the experimental group (12 men and 20 women) who underwent the GPR session, and a control group (13 men and 19 women) that did not receive any intervention was included. Center of pressure (COP) was assessed using a stabilometric platform, with eyes open and eyes closed before, immediately after, 48 hours after, and 7 days after intervention in both groups. In the interaction of time and gender, statistically significant differences were found for the area covered by COP (P = .020) and for the standard deviation (SD) in the mediolateral axis (P = .035). Considering the complete interaction time, gender, and group, statistically significant differences were found (P = .015) for the anteroposterior rate covered by COP and the SD in the anteroposterior axis (P = .033). In eyes closed condition, the intersubject analysis showed statistically significant differences for the interaction between group and gender for the variable mediolateral SD (P = .043). Considering the interaction of time with group, statistically significant differences were found for full length covered by COP (P = .017). Changes in postural sway were observed after a single GPR session, mainly at 48 hours, with different behaviors between men and women. Copyright © 2017. Published by Elsevier Inc.

  16. The role of conscious control in maintaining stable posture.

    Science.gov (United States)

    Uiga, Liis; Capio, Catherine M; Ryu, Donghyun; Wilson, Mark R; Masters, Rich S W

    2018-02-01

    This study aimed to examine the relationship between conscious control of movements, as defined by the Theory of Reinvestment (Masters & Maxwell, 2008; Masters, Polman, & Hammond, 1993), and both traditional and complexity-based COP measures. Fifty-three young adults (mean age=20.93±2.53years), 39 older adults with a history of falling (mean age=69.23±3.84years) and 39 older adults without a history of falling (mean age=69.00±3.72years) were asked to perform quiet standing balance in single- and dual-task conditions. The results showed that higher scores on the Movement Specific Reinvestment Scale (MSRS; Masters, Eves, & Maxwell, 2005; Masters & Maxwell, 2008), a psychometric measure of the propensity for conscious involvement in movement, were associated with larger sway amplitude and a more constrained (less complex) mode of balancing in the medial-lateral direction for young adults only. Scores on MSRS explained approximately 10% of total variation in the medial-lateral sway measures. This association was not apparent under dual-task conditions, during which a secondary task was used to limit the amount of cognitive resources available for conscious processing. No relationship between postural control and score on the MSRS was found for either older adult fallers or non-fallers. Possible explanations for these results are discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

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

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    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.

  18. Postural Control in Bilateral Vestibular Failure: Its Relation to Visual, Proprioceptive, Vestibular, and Cognitive Input

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    Andreas Sprenger

    2017-09-01

    Full Text Available Patients with bilateral vestibular failure (BVF suffer from postural and gait unsteadiness with an increased risk of falls. The aim of this study was to elucidate the differential role of otolith, semicircular canal (SSC, visual, proprioceptive, and cognitive influences on the postural stability of BVF patients. Center-of-pressure displacements were recorded by posturography under six conditions: target visibility; tonic head positions in the pitch plane; horizontal head shaking; sensory deprivation; dual task; and tandem stance. Between-group analysis revealed larger postural sway in BVF patients on eye closure; but with the eyes open, BVF did not differ from healthy controls (HCs. Head tilts and horizontal head shaking increased sway but did not differ between groups. In the dual task condition, BVF patients maintained posture indistinguishable from controls. On foam and tandem stance, postural sway was larger in BVF, even with the eyes open. The best predictor for the severity of bilateral vestibulopathy was standing on foam with eyes closed. Postural control of our BVF was indistinguishable from HCs once visual and proprioceptive feedback is provided. This distinguishes them from patients with vestibulo-cerebellar disorders or functional dizziness. It confirms previous reports and explains that postural unsteadiness of BVF patients can be missed easily if not examined by conditions of visual and/or proprioceptive deprivation. In fact, the best predictor for vestibular hypofunction (VOR gain was examining patients standing on foam with the eyes closed. Postural sway in that condition increased with the severity of vestibular impairment but not with disease duration. In the absence of visual control, impaired otolith input destabilizes BVF with head retroflexion. Stimulating deficient SSC does not distinguish patients from controls possibly reflecting a shift of intersensory weighing toward proprioceptive-guided postural control. Accordingly

  19. GOLFING SKILL LEVEL POSTURAL CONTROL DIFFERENCES: A BRIEF REPORT

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    James S. Wrobel

    2012-09-01

    Full Text Available Golfers have better balance than their age-matched counterparts; however, it is uncertain if this persists during the swing as a function of skill level. The purpose of the study was to investigate dynamic postural control (center of mass (COM motion measured during different phases of the swing in golfers of varying proficiency. Eighteen healthy golfers were grouped by handicap: novice (no handicap, n = 7, intermediate (handicap 15-19, n = 7, and advanced (handicap 9-14, n = 4. Indoor testing was performed hitting 3 tee shots using a common driver. A five-camera (60 Hz motion analysis system (9 markers was used to extract kinematics data. There were no significant group differences in gender, age, or BMI. Advanced players had lower COM displacement with respect to address at the time of maximum arm speed (p = 0. 001 compared to intermediate (57%, p = 0.014 and novice (73%, p = 0.023. These changes persisted after COM distance and time normalization. Advanced golfers had improved COM linearity during the downswing (p < 0.001 compared to intermediate (30%, p = 0.029 and novice (51%, p < 0.001. Advanced players had decreased COM displacement at the time of maximum arm speed and a more linear COM path during the early downswing. Further study should focus on these changes during ball launch conditions

  20. Postural control and balance self-efficacy in women with fibromyalgia: are there differences?

    Science.gov (United States)

    Muto, L H A; Sauer, J F; Yuan, S L K; Sousa, A; Mango, P C; Marques, A P

    2015-04-01

    Fibromyalgia (FM) is a rheumatic disease characterized by chronic widespread pain and symptoms such as fatigue, sleep disturbances, cognitive difficulties, and depression. Postural instability is a debilitating disorder increasingly recognized as part of FM. To assess and compare postural control and balance self-efficacy in women with and without FM and verify the association of these variables with pain, symptom severity, and strength. Case-control study Physiotherapeutic Clinical Research and Electromyography Laboratory Department of Physical Therapy, Speech Therapy, and Occupational Therapy, School of Medicine, University of Sao Paulo, Sao Paulo, Brazil. Case-control study of 117 women ranging from age 35 to 60 years. Of these, 67 had FM. Posture control was assessed with the modified clinical test of sensory interaction on balance with patients in forceplates, balance self-efficacy with the Activities-specific Balance Confidence Scale, pain severity with the Visual Analog Scale, tender point pain threshold with digital algometry, symptom severity with the fibromyalgia impact questionnaire, and lower limb strength with a dynamometer. Individuals with FM had impaired postural control showing increased speed of oscillation of the center of gravity (P=0.004) and decreased balance self-efficacy (Pcorrelations of balance self-efficacy with pain (r=0.7, PCorrelation of postural control with the same variables was weak. Patients with FM have impaired postural control and low balance self-efficacy that are associated with pain, muscle strength, and symptom severity. Postural control and balance self-efficacy needs to be assessed in patients with FM and the treatment goals should be the improvement of postural control and balance self-efficacy.

  1. The influence of visual information on multi-muscle control during quiet stance: a spectral analysis approach

    NARCIS (Netherlands)

    Danna-Dos-Santos, A.; Degani, A.M.; Boonstra, T.W.; Mochizuki, L.; Harney, A.M.; Schmeckpeper, M.M; Tabor, L.C.; Leonard, C.T.

    2015-01-01

    Standing upright requires the coordination of neural drives to a large set of muscles involved in controlling human bipedal stance (i.e., postural muscles). The coordination may deteriorate in situations where standing is performed under more challenging circumstances, such as standing on a smaller

  2. Postural control of small for gestational age infants born at term Controle postural de lactentes nascidos a termo pequenos para a idade gestacional

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    D Campos

    2007-02-01

    Full Text Available OBJECTIVE: This study compared the postural control of small (SGA and appropriate (AGA for gestational age infants born at term, at the ages of 3, 6, 9 and 12 months. METHOD: This was a cohort study of infants born at term, with birth weight less than the 10th percentile for the SGA group and between the 10th and 90th percentiles for the AGA group. Infants with genetic syndromes, malformations, congenital infections and internment in neonatal intensive care unit were excluded. The evaluation instrument was the Alberta Infant Motor Scale. RESULTS: Comparison of the SGA and AGA groups did not show any significant differences (p>0.05 at the assessment times. However, the postural control of the SGA group was influenced by the gestational age (r=-0.83; p= 0.006 and 5th minute Apgar (r= 0.79; p= 0.01 in the 3rd month, and by maternal occupation (r= 0.67; p= 0.01 in the 6th month. CONCLUSION: It was concluded that the postural control was similar in the groups. However, the postural control of the SGA group was influenced by biological and environmental factors.OBJETIVO: Este estudo teve por objetivo comparar o controle postural de lactentes nascidos a termo, pequenos (PIG e adequados para a idade gestacional (AIG nos 3º, 6º, 9º e 12º meses. MÉTODO: Estudo longitudinal de lactentes nascidos a termo, com peso de nascimento menor que o percentil 10 para o grupo PIG e entre o percentil 10 e 90 para o grupo AIG. Síndromes genéticas, más-formações, infecções congênitas e internados em unidade de terapia intensiva neonatal foram excluídos. O instrumento de avaliação foi Alberta Infant Motor Scale. RESULTADOS: A comparação do grupo PIG e AIG não mostrou diferença significativa (p> 0,05 nos meses avaliados. Entretanto, o controle postural do grupo PIG foi influenciado pela idade gestacional (r= -0,83/p= 0,006 e Apgar de 5' (r= 0,79/p= 0,01 no 3º mês; e pela ocupação materna (r= 0,67/p= 0,01 no 6º mês. CONCLUSÃO: Concluiu-se que o

  3. Adolescent standing postural response to backpack loads: a randomised controlled experimental study

    Directory of Open Access Journals (Sweden)

    Pirunsan Ubon

    2002-04-01

    Full Text Available Abstract Background Backpack loads produce changes in standing posture when compared with unloaded posture. Although 'poor' unloaded standing posture has been related to spinal pain, there is little evidence of whether, and how much, exposure to posterior load produces injurious effects on spinal tissue. The objective of this study was to describe the effect on adolescent sagittal plane standing posture of different loads and positions of a common design of school backpack. The underlying study aim was to test the appropriateness of two adult 'rules-of-thumb'-that for postural efficiency, backpacks should be worn high on the spine, and loads should be limited to 10% of body weight. Method A randomised controlled experimental study was conducted on 250 adolescents (12–18 years, randomly selected from five South Australian metropolitan high schools. Sagittal view anatomical points were marked on head, neck, shoulder, hip, thigh, knee and ankle. There were nine experimental conditions: combinations of backpack loads (3, 5 or 10% of body weight and positions (backpack centred at T7, T12 or L3. Sagittal plane photographs were taken of unloaded standing posture (baseline, and standing posture under the experimental conditions. Posture was quantified from the x (horizontal coordinate of each anatomical point under each experimental condition. Differences in postural response were described, and differences between conditions were determined using Analysis of Variance models. Results Neither age nor gender was a significant factor when comparing postural response to backpack loads or conditions. Backpacks positioned at T7 produced the largest forward (horizontal displacement at all the anatomical points. The horizontal position of all anatomical points increased linearly with load. Conclusion There is evidence refuting the 'rule-of-thumb' to carry the backpack high on the back. Typical school backpacks should be positioned with the centre at waist or

  4. Pain relief is associated with decreasing postural sway in patients with non-specific low back pain

    DEFF Research Database (Denmark)

    Ruhe, A.; Fejer, René; Walker, B.

    2012-01-01

    Background: Increased postural sway is well documented in patients suffering from non-specific low back pain, whereby a linear relationship between higher pain intensities and increasing postural sway has been described. No investigation has been conducted to evaluate whether this relationship...... is maintained if pain levels change in adults with non-specific low back pain. Methods: Thirty-eight patients with non-specific low back pain and a matching number of healthy controls were enrolled. Postural sway was measured by three identical 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). The patients received three manual interventions (e. g. manipulation, mobilization or soft tissue techniques) at 3-4 day intervals, postural sway measures were obtained at each occasion. Results...

  5. Comparative Effectiveness of Plantar-Massage Techniques on Postural Control in Those With Chronic Ankle Instability.

    Science.gov (United States)

    Wikstrom, Erik A; Song, Kyeongtak; Lea, Ashley; Brown, Nastassia

    2017-07-01

      One of the major concerns after an acute lateral ankle sprain is the potential for development of chronic ankle instability (CAI). The existing research has determined that clinician-delivered plantar massage improves postural control in those with CAI. However, the effectiveness of self-administered treatments and the underlying cause of any improvements remain unclear.   To determine (1) the effectiveness of a self-administered plantar-massage treatment in those with CAI and (2) whether the postural-control improvements were due to the stimulation of the plantar cutaneous receptors.   Crossover study.   University setting.   A total of 20 physically active individuals (6 men and 14 women) with self-reported CAI.   All participants completed 3 test sessions involving 3 treatments: a clinician-delivered manual plantar massage, a patient-delivered self-massage with a ball, and a clinician-delivered sensory brush massage.   Postural control was assessed using single-legged balance with eyes open and the Star Excursion Balance Test.   Static postural control improved (P ≤ .014) after each of the interventions. However, no changes in dynamic postural control after any of the interventions were observed (P > .05). No differences were observed between a clinician-delivered manual plantar massage and either a patient-delivered self-massage with a ball or a clinician-delivered sensory brush massage in any postural-control outcome.   In those with CAI, single 5-minute sessions of traditional plantar massage, self-administered massage, and sensory brush massage each resulted in comparable static postural-control improvements. The results also provide empirical evidence suggesting that the mechanism for the postural-control improvements is the stimulation of the plantar cutaneous receptors.

  6. A method to model anticipatory postural control in driver braking events.

    Science.gov (United States)

    Östh, Jonas; Eliasson, Erik; Happee, Riender; Brolin, Karin

    2014-09-01

    Human body models (HBMs) for vehicle occupant simulations have recently been extended with active muscles and postural control strategies. Feedback control has been used to model occupant responses to autonomous braking interventions. However, driver postural responses during driver initiated braking differ greatly from autonomous braking. In the present study, an anticipatory postural response was hypothesized, modelled in a whole-body HBM with feedback controlled muscles, and validated using existing volunteer data. The anticipatory response was modelled as a time dependent change in the reference value for the feedback controllers, which generates correcting moments to counteract the braking deceleration. The results showed that, in 11 m/s(2) driver braking simulations, including the anticipatory postural response reduced the peak forward displacement of the head by 100mm, of the shoulder by 30 mm, while the peak head flexion rotation was reduced by 18°. The HBM kinematic response was within a one standard deviation corridor of corresponding test data from volunteers performing maximum braking. It was concluded that the hypothesized anticipatory responses can be modelled by changing the reference positions of the individual joint feedback controllers that regulate muscle activation levels. The addition of anticipatory postural control muscle activations appears to explain the difference in occupant kinematics between driver and autonomous braking. This method of modelling postural reactions can be applied to the simulation of other driver voluntary actions, such as emergency avoidance by steering. Copyright © 2014. Published by Elsevier B.V.

  7. Haptic cues for orientation and postural control in sighted and blind individuals

    Science.gov (United States)

    Jeka, J. J.; Easton, R. D.; Bentzen, B. L.; Lackner, J. R.

    1996-01-01

    Haptic cues from fingertip contact with a stable surface attenuate body sway in subjects even when the contact forces are too small to provide physical support of the body. We investigated how haptic cues derived from contact of a cane with a stationary surface at low force levels aids postural control in sighted and congenitally blind individuals. Five sighted (eyes closed) and five congenitally blind subjects maintained a tandem Romberg stance in five conditions: (1) no cane; (2,3) touch contact (postural sway in all subjects, compared to the no-cane condition. A slanted cane was far more effective in reducing postural sway than was a perpendicular cane. Cane use also decreased head displacement of sighted subjects far more than that of blind subjects. These results suggest that head movement control is linked to postural control through gaze stabilization reflexes in sighted subjects; such reflexes are absent in congenitally blind individuals and may account for their higher levels of head displacement.

  8. Aging causes a reorganization of cortical and spinal control of posture

    Directory of Open Access Journals (Sweden)

    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.

  9. Balance ability and postural stability among patients with painful shoulder disorders and healthy controls.

    Science.gov (United States)

    Baierle, Tobias; Kromer, Thilo; Petermann, Carmen; Magosch, Petra; Luomajoki, Hannu

    2013-10-02

    In therapeutic settings, patients with shoulder pain often exhibit deficient coordinative abilities in their trunk and lower extremities. The aim of the study was to investigate 1) if there is a connection between shoulder pain and deficits in balance ability and postural stability, 2) if pain intensity is related to balance ability and postural stability, and 3) if there is a connection between body mass index (BMI) and balance ability and postural stability. In this case-control study, patients (n = 40) with pathological shoulder pain (> 4 months) were matched with a healthy controls (n = 40) and were compared with regard to their balance ability and postural stability. Outcome parameters were postural stability, balance ability and symmetry index which were measured using the S3-Check system. In addition, the influence of shoulder pain intensity and BMI on the outcome parameters was analysed. Patients with shoulder pain showed significantly worse results in measurements of postural stability right/left (p shoulder pain group. There was no correlation between pain intensity and measurements of balance ability or postural stability. Likewise, no correlation between BMI and deficiencies in balance ability and postural stability was established. Patients with pathological shoulder pain (> 4 months) have deficiencies in balance ability and postural stability; however the underlying mechanisms for this remain unclear. Neither pain intensity nor BMI influenced the outcome parameters. Patients with shoulder pain shift their weight to the affected side. Further research is needed to determine if balance training can improve rehabilitation results in patients with shoulder pathologies.

  10. Vertical heterophoria and postural control in nonspecific chronic low back pain.

    Directory of Open Access Journals (Sweden)

    Eric Matheron

    Full Text Available The purpose of this study was to test postural control during quiet standing in nonspecific chronic low back pain (LBP subjects with vertical heterophoria (VH before and after cancellation of VH; also to compare with healthy subjects with, and without VH. Fourteen subjects with LBP took part in this study. The postural performance was measured through the center of pressure displacements with a force platform while the subjects fixated on a target placed at either 40 or 200 cm, before and after VH cancellation with an appropriate prism. Their postural performance was compared to that of 14 healthy subjects with VH and 12 without VH (i.e. vertical orthophoria studied previously in similar conditions. For LBP subjects, cancellation of VH with a prism improved postural performance. With respect to control subjects (with or without VH, the variance of speed of the center of pressure was higher, suggesting more energy was needed to stabilize their posture in quiet upright stance. Similarly to controls, LBP subjects showed higher postural sway when they were looking at a target at a far distance than at a close distance. The most important finding is that LBP subjects with VH can improve their performance after prism-cancellation of their VH. We suggest that VH reflects mild conflict between sensory and motor inputs involved in postural control i.e. a non optimal integration of the various signals. This could affect the performance of postural control and perhaps lead to pain. Nonspecific chronic back pain may results from such prolonged conflict.

  11. Postural stability in patients with knee osteoarthritis: comparison with controls and evaluation of relationships between postural stability scores and International Classification of Functioning, Disability and Health components.

    Science.gov (United States)

    Hsieh, Ru-Lan; Lee, Wen-Chung; Lo, Min-Tzu; Liao, Wei-Cheng

    2013-02-01

    To assess the differences in postural stability between patients with knee osteoarthritis and controls without knee osteoarthritis, and to evaluate possible relations between postural stability scores and International Classification of Functioning, Disability and Health (ICF) components. An age-matched, case-controlled trial with a cross-sectional design. A teaching hospital. Patients with knee osteoarthritis (n=73) and age-matched controls (n=60). Data on patients' postural stability and additional health-related variables were collected using various instruments. These included the Hospital Anxiety and Depression Scale, the Multidimensional Fatigue Inventory, the World Health Organization Quality of Life Brief Version, the physical function test (chair-rising time), the Chinese version of the Western Ontario and McMaster Universities Osteoarthritis Index, the Chinese version of the Knee Injury and Osteoarthritis Outcome Score, and the Biodex Stability System. A comparison of postural stability in patients with knee osteoarthritis versus that of controls was performed. The relation between postural stability scores for patients with knee osteoarthritis and ICF components was evaluated. Pearson correlation tests were used to determine the variables that correlated with postural stability among these patients. Patients with knee osteoarthritis displayed lower overall postural stability than controls (scores of 0.7 vs. 0.5, P=.006) and scored lower on the environmental domain of the World Health Organization Quality of Life Brief Version (62.2 vs 66.8, P=.014). For patients with knee osteoarthritis, postural stability was weakly associated with the ICF components of body functions and structures, including pain (r=.33-.34, P=.004), physical fatigue (r=.28, P=.016), and reduced motivation (r=.30, P=.011). Weak to moderate associations between postural stability and the ICF components of activities and participation were found; the relevant ICF variables included

  12. A randomized, controlled trial of physician postures when breaking bad news to cancer patients.

    Science.gov (United States)

    Bruera, Eduardo; Palmer, J Lynn; Pace, Ellen; Zhang, Karen; Willey, Jie; Strasser, Florian; Bennett, Michael I

    2007-09-01

    Medical training teaches physicians to sit when breaking bad news, though there have been no controlled studies to support this advice. We aimed to establish cancer patients' preference for physician posture when physicians break bad news using a randomized controlled crossover trial in a department of palliative care at a large US cancer center. Referred patients were blind to the hypothesis and watched video sequences of a sitting or standing physician breaking bad news to a cancer patient and 168 of 173 participants (88 female) completed the study. Sitting physicians were preferred and viewed as significantly more compassionate than standing physicians (P importance than posture. In summary, cancer patients, especially females, prefer physicians to sit when breaking bad news and rate physicians who adopt this posture as more compassionate. However, sitting posture alone is unlikely to compensate for poor communication skills and lack of other respectful gestures during a consultation.

  13. Personality traits and individual differences predict threat-induced changes in postural control.

    Science.gov (United States)

    Zaback, Martin; Cleworth, Taylor W; Carpenter, Mark G; Adkin, Allan L

    2015-04-01

    This study explored whether specific personality traits and individual differences could predict changes in postural control when presented with a height-induced postural threat. Eighty-two healthy young adults completed questionnaires to assess trait anxiety, trait movement reinvestment (conscious motor processing, movement self-consciousness), physical risk-taking, and previous experience with height-related activities. Tests of static (quiet standing) and anticipatory (rise to toes) postural control were completed under low and high postural threat conditions. Personality traits and individual differences significantly predicted height-induced changes in static, but not anticipatory postural control. Individuals less prone to taking physical risks were more likely to lean further away from the platform edge and sway at higher frequencies and smaller amplitudes. Individuals more prone to conscious motor processing were more likely to lean further away from the platform edge and sway at larger amplitudes. Individuals more self-conscious about their movement appearance were more likely to sway at smaller amplitudes. Evidence is also provided that relationships between physical risk-taking and changes in static postural control are mediated through changes in fear of falling and physiological arousal. Results from this study may have indirect implications for balance assessment and treatment; however, further work exploring these factors in patient populations is necessary. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. 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 ...

  15. Functional synergies underlying control of upright posture during changes in head orientation.

    Directory of Open Access Journals (Sweden)

    Eunse Park

    Full Text Available BACKGROUND: Studies of human upright posture typically have stressed the need to control ankle and hip joints to achieve postural stability. Recent studies, however, suggest that postural stability involves multi degree-of-freedom (DOF coordination, especially when performing supra-postural tasks. This study investigated kinematic synergies related to control of the body's position in space (two, four and six DOF models and changes in the head's orientation (six DOF model. METHODOLOGY/PRINCIPAL FINDINGS: Subjects either tracked a vertically moving target with a head-mounted laser pointer or fixated a stationary point during 4-min trials. Uncontrolled manifold (UCM analysis was performed across tracking cycles at each point in time to determine the structure of joint configuration variance related to postural stability or tracking consistency. The effect of simulated removal of covariance among joints on that structure was investigated to further determine the role of multijoint coordination. Results indicated that cervical joint motion was poorly coordinated with other joints to stabilize the position of the body center of mass (CM. However, cervical joints were coordinated in a flexible manner with more caudal joints to achieve consistent changes in head orientation. CONCLUSIONS/SIGNIFICANCE: An understanding of multijoint coordination requires reference to the stability/control of important performance variables. The nature of that coordination differs depending on the reference variable. Stability of upright posture primarily involved multijoint coordination of lower extremity and lower trunk joints. Consistent changes in the orientation of the head, however, required flexible coordination of those joints with motion of the cervical spine. A two-segment model of postural control was unable to account for the observed stability of the CM position during the tracking task, further supporting the need to consider multijoint coordination to

  16. Postural stability and ankle sprain history in athletes compared to uninjured controls.

    Science.gov (United States)

    Huurnink, Arnold; Fransz, Duncan P; Kingma, Idsart; Verhagen, Evert A L M; van Dieën, Jaap H

    2014-02-01

    Diminished postural stability is a risk factor for ankle sprain occurrence and ankle sprains result in impaired postural stability. To date, ankle sprain history has not been taken into account as a determinant of postural stability, while it could possibly specify subgroups of interest. Postural stability was compared between 18 field hockey athletes who had recovered from an ankle sprain (mean (SD); 3.6 (1.5) months post-injury), and 16 uninjured controls. Force plate and kinematics parameters were calculated during single-leg standing: mean center of pressure speed, mean absolute horizontal ground reaction force, mean absolute ankle angular velocity, and mean absolute hip angular velocity. Additionally, cluster analysis was applied to the 'injured' participants, and the cluster with diminished postural stability was compared to the other participants with respect to ankle sprain history. MANCOVA showed no significant difference between groups in postural stability (P = 0.68). A self-reported history of an (partial) ankle ligament rupture was typically present in the cluster with diminished postural stability. Subsequently, a 'preceding rupture' was added as a factor in the MANCOVA, which showed a significant association between diminished postural stability and a 'preceding rupture' (P = 0.01), for all four individual parameters (P: 0.001-0.029; Cohen's d: 0.96-2.23). Diminished postural stability is not apparent in all previously injured athletes. However, our analysis suggests that an (mild) ankle sprain with a preceding severe ankle sprain is associated with impaired balance ability. Therefore, sensorimotor training may be emphasized in this particular group and caution is warranted in return to play decisions. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Application of Machine Learning in Postural Control Kinematics for the Diagnosis of Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    Luís Costa

    2016-01-01

    Full Text Available The use of wearable devices to study gait and postural control is a growing field on neurodegenerative disorders such as Alzheimer’s disease (AD. In this paper, we investigate if machine-learning classifiers offer the discriminative power for the diagnosis of AD based on postural control kinematics. We compared Support Vector Machines (SVMs, Multiple Layer Perceptrons (MLPs, Radial Basis Function Neural Networks (RBNs, and Deep Belief Networks (DBNs on 72 participants (36 AD patients and 36 healthy subjects exposed to seven increasingly difficult postural tasks. The decisional space was composed of 18 kinematic variables (adjusted for age, education, height, and weight, with or without neuropsychological evaluation (Montreal cognitive assessment (MoCA score, top ranked in an error incremental analysis. Classification results were based on threefold cross validation of 50 independent and randomized runs sets: training (50%, test (40%, and validation (10%. Having a decisional space relying solely on postural kinematics, accuracy of AD diagnosis ranged from 71.7 to 86.1%. Adding the MoCA variable, the accuracy ranged between 91 and 96.6%. MLP classifier achieved top performance in both decisional spaces. Having comprehended the interdynamic interaction between postural stability and cognitive performance, our results endorse machine-learning models as a useful tool for computer-aided diagnosis of AD based on postural control kinematics.

  18. The influence of fear of falling on orthostatic postural control: a systematic review

    Directory of Open Access Journals (Sweden)

    Nélio Silva de Souza

    2015-12-01

    Full Text Available Posture is a complex sensory-motor behavior that can be influenced by the fear of falling (FoF during environmental changes. The aim of this paper is to investigate the influence of FoF on orthostatic postural control in healthy individuals by a systematic review. Thirteen articles were selected. Some other articles (31 references were used to contextualize and discuss the topic. Studies in the environment made changes on the environment, in which participants were positioned in high hydraulic platforms at different heights, showed a decrease in the center of pressure in the anteroposterior oscillation where the platform was higher. This change in postural control strategy and the FoF are correlated. It can modulate the activity of the muscle spindle (H-reflex and probably induce postural freezing phenomenon (anticipated postural anxiety. We can conclude that further studies are needed to understand the physiological mechanisms involved in FoF and its relation to changes in postural control strategy.

  19. Application of Machine Learning in Postural Control Kinematics for the Diagnosis of Alzheimer's Disease.

    Science.gov (United States)

    Costa, Luís; Gago, Miguel F; Yelshyna, Darya; Ferreira, Jaime; David Silva, Hélder; Rocha, Luís; Sousa, Nuno; Bicho, Estela

    2016-01-01

    The use of wearable devices to study gait and postural control is a growing field on neurodegenerative disorders such as Alzheimer's disease (AD). In this paper, we investigate if machine-learning classifiers offer the discriminative power for the diagnosis of AD based on postural control kinematics. We compared Support Vector Machines (SVMs), Multiple Layer Perceptrons (MLPs), Radial Basis Function Neural Networks (RBNs), and Deep Belief Networks (DBNs) on 72 participants (36 AD patients and 36 healthy subjects) exposed to seven increasingly difficult postural tasks. The decisional space was composed of 18 kinematic variables (adjusted for age, education, height, and weight), with or without neuropsychological evaluation (Montreal cognitive assessment (MoCA) score), top ranked in an error incremental analysis. Classification results were based on threefold cross validation of 50 independent and randomized runs sets: training (50%), test (40%), and validation (10%). Having a decisional space relying solely on postural kinematics, accuracy of AD diagnosis ranged from 71.7 to 86.1%. Adding the MoCA variable, the accuracy ranged between 91 and 96.6%. MLP classifier achieved top performance in both decisional spaces. Having comprehended the interdynamic interaction between postural stability and cognitive performance, our results endorse machine-learning models as a useful tool for computer-aided diagnosis of AD based on postural control kinematics.

  20. Relação entre sensibilidade plantar e controle postural em jovens e idosos

    Directory of Open Access Journals (Sweden)

    Letícia Suemi Ueda

    2013-03-01

    Full Text Available DOI: http://dx.doi.org/10.5007/1980-0037.2013v15n2p215 A diminuição da sensibilidade plantar em idosos acarreta alterações na locomoção e no controle postural que podem aumentar o risco de quedas. Compreender o uso de aferências podais em idosos pode auxiliar na prevenção da perda de mobilidade e quedas. Contudo, a relação entre a sensibilidade de diferentes regiões do pé e alterações no controle postural representa uma lacuna na literatura. Com o propósito de investigar esta lacuna na literatura, o objetivo deste estudo foi avaliar a relação entre a sensibilidade plantar e o controle postural em jovens e idosos. Foram avaliados 42 participantes, organizados em dois grupos de acordo com a faixa etária (jovens ou idosos. Os participantes foram avaliados quanto às características antropométricas, sensibilidade dos pés (usando monofilamentos e controle postural (usando plataforma de força. Os índices de sensibilidade plantar e de controle postural foram correlacionados e comparados entre os grupos. Os resultados mostraram que idosos tiveram menor sensibilidade dos pés e pior controle postural do que jovens. A amplitude ântero-posterior e a área do centro de pressão de idosos tiveram correlação com a sensibilidade plantar geral, mas não com regiões específicas do pé. Para jovens, a sensibilidade na região do antepé esteve relacionada com o melhor controle postural.

  1. Diurnal changes in postural control in normal children: Computerized static and dynamic assessments

    Directory of Open Access Journals (Sweden)

    Sophie Bourelle

    2014-07-01

    Full Text Available Mild traumatic brain injury (mTBI causes postural control deficits and accordingly comparison of aberrant postural control against normal postural control may help diagnose mTBI. However, in the current literature, little is known regarding the normal pattern of postural control in young children. This study was therefore conducted as an effort to fill this knowledge gap. Eight normal school-aged children participated. Posture assessment was conducted before (7-8 a.m. in the morning and after (4-7 p.m. in the afternoon school on regular school days using the Balance Master ® evaluation system composed of 3 static tests and 2 dynamic balance tests. A significant difference in the weight-bearing squats was detected between morning hours and afternoon hours (P < 0.05. By end of afternoon, the body weight was borne mainly on the left side with the knee fully extended and at various degrees of knee flexion. A significantly better directional control of the lateral rhythmic weight shifts was observed at the end of the afternoon than at morning hours (P < 0.05. In summary, most of our findings are inconsistent with results from previous studies in adults, suggesting age-related differences in posture control in humans. On a regular school day, the capacity of postural control and laterality or medio-lateral balance in children varies between morning and afternoon hours. We suggest that posturographic assessment in children, either in normal (e.g., physical education and sports training or in abnormal conditions (e.g., mTBI-associated balance disorders, be better performed late in the afternoon.

  2. The Effects of Multisensory Balance Training on Postural Control in Older Adults

    Directory of Open Access Journals (Sweden)

    Farnoosh Shams

    2011-10-01

    Full Text Available Objectives: It has been found that older adults fall or sway significantly more than younger ones under sensory conflict conditions. Considering the prospects of future increases in the elderly population size of Iran and the lack of proper postural control and the high costs of its probable consequences, this study investigated the effects of multi balance training on postural control. Methods & Materials: In this semi-experimental study, 34 elderly women participated in two training and control groups with the mean ages of 72.4 and 72.9 respectively. Before and after training, to investigate the functional balance and postural control, the Berg Balance Scale and a force plate were used. The training group participated in multisensory balance training sessions of 1 hour classes held three days per week for five weeks. Data was analyzed using an independent sample and a paired t-test. Results: The analysis showed significant differences between the training group and the control after balance training in the measured parameters of postural control consisting of path length and mean velocity in the eyes open (P=0.001 and eyes closed (P=0.0001 conditions and the Berg Balance Scale (P=0.002. Conclusion: Results indicate that multisensory balance training can improve the parameters of postural control even in short term.

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

    Science.gov (United States)

    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.

  4. Effects of Pilates exercises on sensory interaction, postural control and fatigue in patients with multiple sclerosis.

    Science.gov (United States)

    Soysal Tomruk, Melda; Uz, Muhammed Zahid; Kara, Bilge; İdiman, Egemen

    2016-05-01

    Decreased postural control, sensory integration deficits and fatigue are important problems that cause functional impairments in patients with multiple sclerosis (pwMS). To examine the effect of modified clinical Pilates exercises on sensory interaction and balance, postural control and fatigue in pwMS. Eleven patients with multiple sclerosis and 12 healthy matched controls were recruited in this study. Limits of stability and postural stability tests were used to evaluate postural control by Biodex Balance System and sensory interaction assessed. Fatigue was assessed by Modified Fatigue Impact Scale. Pilates exercises were applied two times a week for 10 weeks and measurements were repeated to pwMS after exercise training. Postural control and fatigue (except psychosocial parameter) of pwMS were significantly worser than healthy controls (pPilates training (ppilates exercises (p>0.05). Ten-week Pilates training is effective to improve sensory interaction and to decrease fatigue. Pilates exercises can be applied safely in ambulatory pwMS for enhance sensory interaction and balance and combat fatigue. More investigations are needed. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Contribution of the multifidus muscle for control of upright posture in subjects with spina bifida occulta.

    Science.gov (United States)

    Chang, Shin-Tsu; Ku, Chih-Hung; Hsieh, Ming-Fu; Chen, Liang-Cheng; Chu, Heng-Yi; Chang, Cheng-Chiang; Tsai, Kao-Chung

    2008-08-01

    The multifidus muscle plays a role in controlling lumbosacral position and postural sway. One of its attachment sites is the exact site of spina bifida occulta (SBO). To investigate the role of the muscle for postural control in SBO. Cross-sectional cohort. Eighty subjects with SBO (38 in minor; 42 in major) and controls. N/A. Subjects stood upright on a platform at 0 degrees and on an inclined surface (10 degrees and 20 degrees) with feet in plantarflexion/dorsiflexion, together with eyes open and closed. The platform system measured posture to obtain sway area and sway mean for statistics. Upon sway area/mean, the group differences of major/minor SBO vs. control were all significant. Sway means of minor SBO were lower than those of major SBO at corresponding inclined degrees. Subjects with SBO demonstrated increased sway as compared to controls.

  6. Learning effects of dynamic postural control by auditory biofeedback versus visual biofeedback training.

    Science.gov (United States)

    Hasegawa, Naoya; Takeda, Kenta; Sakuma, Moe; Mani, Hiroki; Maejima, Hiroshi; Asaka, Tadayoshi

    2017-10-01

    Augmented sensory biofeedback (BF) for postural control is widely used to improve postural stability. However, the effective sensory information in BF systems of motor learning for postural control is still unknown. The purpose of this study was to investigate the learning effects of visual versus auditory BF training in dynamic postural control. Eighteen healthy young adults were randomly divided into two groups (visual BF and auditory BF). In test sessions, participants were asked to bring the real-time center of pressure (COP) in line with a hidden target by body sway in the sagittal plane. The target moved in seven cycles of sine curves at 0.23Hz in the vertical direction on a monitor. In training sessions, the visual and auditory BF groups were required to change the magnitude of a visual circle and a sound, respectively, according to the distance between the COP and target in order to reach the target. The perceptual magnitudes of visual and auditory BF were equalized according to Stevens' power law. At the retention test, the auditory but not visual BF group demonstrated decreased postural performance errors in both the spatial and temporal parameters under the no-feedback condition. These findings suggest that visual BF increases the dependence on visual information to control postural performance, while auditory BF may enhance the integration of the proprioceptive sensory system, which contributes to motor learning without BF. These results suggest that auditory BF training improves motor learning of dynamic postural control. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Design, implementation and stabilization of a Bipedal robot

    Science.gov (United States)

    Nath, Alok; Das, Goutam; Mallick, Anik; Chowdhury, Shovan

    2017-12-01

    In this paper, we have presented the mechanical design and fabrication of a Bipedal walking robot as well as control strategies to be implemented for walking and balance recovery. For this robot, we considered Six Degree of Freedom (D.O.P) in the lower body one at each hip, one at each knee and one at each ankle. Each degree of freedom is powered by a RC servo motor and this robot is controlled by Arduino Mega 2560 micro controller. By balancing center of mass (C.O.M) it walks in rhythmic way as like as human one.

  8. Leisure sports and postural control: can a black belt protect your balance from aging?

    Science.gov (United States)

    Krampe, Ralf T; Smolders, Caroline; Doumas, Michail

    2014-03-01

    To determine potential benefits of intensive leisure sports for age-related changes in postural control, we tested 3 activity groups comprising 70 young (M = 21.67 years, SD = 2.80) and 73 older (M = 62.60 years, SD = 5.19) men. Activity groups were martial artists, who held at least 1st Dan (black belt), sportive individuals exercising sports without explicit balance components, and nonsportive controls. Martial artists had an advantage over sportive individuals in dynamic posture tasks (upright stance on a sway-referenced platform), and these 2 active groups showed better postural control than nonsportive participants. Age-related differences in postural control were larger in nonsportive men compared with the 2 active groups, who were similar in this respect. In contrast, negative age differences in other sensorimotor and cognitive functions did not differ between activity groups. We concluded that individuals engaging in intensive recreational sports have long-term advantages in postural control. However, even in older martial artists with years of practice in their sports, we observed considerable differences favoring the young. (c) 2014 APA, all rights reserved.

  9. Analysis of postural control and muscular performance in young and elderly women in different age groups.

    Science.gov (United States)

    Gomes, Matheus M; Reis, Júlia G; Carvalho, Regiane L; Tanaka, Erika H; Hyppolito, Miguel A; Abreu, Daniela C C

    2015-01-01

    muscle strength and power are two factors affecting balance. The impact of muscle strength and power on postural control has not been fully explored among different age strata over sixty. the aim of the present study was to assess the muscle strength and power of elderly women in different age groups and determine their correlation with postural control. eighty women were divided into four groups: the young 18-30 age group (n=20); the 60-64 age group (n=20); the 65-69 age group (n=20); and the 70-74 age group (n=20). The participants underwent maximum strength (one repetition maximum or 1-RM) and muscle power tests to assess the knee extensor and flexor muscles at 40%, 70%, and 90% 1-RM intensity. The time required by participants to recover their balance after disturbing their base of support was also assessed. the elderly women in the 60-64, 65-69, and 70-74 age groups exhibited similar muscle strength, power, and postural control (p>0.05); however, these values were lower than those of the young group (pstrength and power and the postural control performance (pelderly women aged 60 to 74 years exhibited similar abilities to generate strength and power with their lower limbs, and this ability could be one factor that explains the similar postural control shown by these women.

  10. Athletes who train on unstable compared to stable surfaces exhibit unique postural control strategies in response to balance perturbations

    Directory of Open Access Journals (Sweden)

    D.S. Blaise Williams, III

    2016-03-01

    Conclusion: USA exhibit unique postural strategies compared to SSA. These unique strategies seemingly exhibit a direction-specific attribute and may be associated with divergent motor control strategies.

  11. An experimental controlled study on postural sway and therapeutic exercise in subjects with low back pain.

    Science.gov (United States)

    Kuukkanen, T M; Mälkiä, E A

    2000-04-01

    To describe postural sway and its associations to background factors, low back pain and functional capacity. To evaluate the changes in postural sway after three months of therapeutic exercise in the gym or at home. A one-year randomized experimental trial evaluated postural sway in three study groups: intensive training, home exercise and control group. Subjects were recruited from seven local occupational health care centres in Central Finland and were examined at Central Finland Hospital by medical doctors. Measurements and therapeutic exercise programmes were carried out in the Research Laboratory of Sport and Health Sciences at Jyväskylä University. Initially, 49 male and 41 female subjects (aged 20-55 years) with nonspecific and subacute low back pain were examined. Postural sway using a force platform, the Oswestry Index, as well as a measure of low back pain intensity were measured at the initial stage of the study, directly after interventions, as well as at three and nine months after the interventions. The background variables were not strongly correlated with postural sway. No changes occurred in the amplitude of sway during the study, but the sway velocity of the home exercise group increased. Postural sway measurements with a force platform may be suitable for detecting impairments of balance performance among subjects with pronounced functional or activity limitations and severe low back pain problems. In order to enhance balance performance, specific and customized exercise programmes are required.

  12. Creative Dance Practice Improves Postural Control in a Child With Cerebral Palsy.

    Science.gov (United States)

    Stribling, Kate; Christy, Jennifer

    2017-10-01

    To investigate the effect of creative dance instruction on postural control and balance in an 11-year-old with spastic triplegic cerebral palsy, Gross Motor Function Classification Scale level II. We conducted 1-hour dance interventions twice weekly for 8 weeks, with a focus on somatosensory awareness and movement in all planes of motion. Computerized dynamic posturography using the SMART Balance Master/EquiTest (NeuroCom) was used to assess postural control and balance reactions before the first class and following the final class. Gains in standing stability, balance recovery, directional control, and endpoint excursion of movement were found. Participation in creative dance lessons appears to improve somatosensory effectiveness and postural control in a child with cerebral palsy. Dance is a fun way to improve balance and coordination. These interventions could be easily implemented into programs for children with cerebral palsy.

  13. Human upright posture control models based on multisensory inputs; in fast and slow dynamics.

    Science.gov (United States)

    Chiba, Ryosuke; Takakusaki, Kaoru; Ota, Jun; Yozu, Arito; Haga, Nobuhiko

    2016-03-01

    Posture control to maintain an upright stance is one of the most important and basic requirements in the daily life of humans. The sensory inputs involved in posture control include visual and vestibular inputs, as well as proprioceptive and tactile somatosensory inputs. These multisensory inputs are integrated to represent the body state (body schema); this is then utilized in the brain to generate the motion. Changes in the multisensory inputs result in postural alterations (fast dynamics), as well as long-term alterations in multisensory integration and posture control itself (slow dynamics). In this review, we discuss the fast and slow dynamics, with a focus on multisensory integration including an introduction of our study to investigate "internal force control" with multisensory integration-evoked posture alteration. We found that the study of the slow dynamics is lagging compared to that of fast dynamics, such that our understanding of long-term alterations is insufficient to reveal the underlying mechanisms and to propose suitable models. Additional studies investigating slow dynamics are required to expand our knowledge of this area, which would support the physical training and rehabilitation of elderly and impaired persons. Copyright © 2015 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  14. Controle postural em pacientes com lesão do ligamento cruzado anterior Postural control in patients with anterior cruciate ligament injury

    Directory of Open Access Journals (Sweden)

    Gabriela Borin

    2010-12-01

    Full Text Available A lesão do ligamento cruzado anterior (LCA do joelho acarreta alterações somatosensoriais em função da perda de informações provenientes dos mecanorreceptores presentes no LCA. Esses receptores constituem importante fonte de informação sensorial, afetando o desempenho de vários atos motores, dentre os quais o controle postural. O estudo objetivou analisar o controle postural de indivíduos com joelhos normais e com lesão unilateral do LCA. Participaram 15 voluntários com lesão do LCA (grupo lesado e 15 voluntários com joelhos normais (grupo controle. O controle postural foi analisado por plataforma de força, sendo o voluntário instruído a assumir a situação experimental em apoio unipodal direito e esquerdo, posicionado no centro da plataforma de modo estático e com os olhos fechados. A plataforma de força forneceu informações de forças e momentos no eixo vertical e horizontal, a partir das quais foi obtida a área de deslocamento do centro de pressão nas direções ântero-posterior e médio-lateral. Os resultados mostram que indivíduos com lesão do LCA apresentaram maior amplitude média de oscilação comparados aos do grupo controle, sugerindo que o deficit no controle postural seja devido à perda de informações proprioceptivas nos indivíduos com LCA. Esses resultados têm implicações para a abordagem clínica de indivíduos com lesão do LCA.Anterior cruciate ligament (ACL injury leads to sensorimotor changes due to lack of information from mechanoreceptors at the ACL. These receptors are an important source of sensory information, affecting the performance of various motor responses, among which postural control. The purpose of this study was to assess postural control in individuals with normal knees and with unilateral ACL injury. Fifteen subjects with ACL injury and 15 healthy young subjects (control group were submitted to postural control assessment by standing in single-leg stance (both right and left

  15. Assessing dynamic postural control during exergaming in older adults: A probabilistic approach.

    Science.gov (United States)

    Soancatl Aguilar, V; Lamoth, C J C; Maurits, N M; Roerdink, J B T M

    2018-02-01

    Digital games controlled by body movements (exergames) have been proposed as a way to improve postural control among older adults. Exergames are meant to be played at home in an unsupervised way. However, only few studies have investigated the effect of unsupervised home-exergaming on postural control. Moreover, suitable methods to dynamically assess postural control during exergaming are still scarce. Dynamic postural control (DPC) assessment could be used to provide both meaningful feedback and automatic adjustment of exergame difficulty. These features could potentially foster unsupervised exergaming at home and improve the effectiveness of exergames as tools to improve balance control. The main aim of this study is to investigate the effect of six weeks of unsupervised home-exergaming on DPC as assessed by a recently developed probabilistic model. High probability values suggest 'deteriorated' postural control, whereas low probability values suggest 'good' postural control. In a pilot study, ten healthy older adults (average 77.9, SD 7.2 years) played an ice-skating exergame at home half an hour per day, three times a week during six weeks. The intervention effect on DPC was assessed using exergaming trials recorded by Kinect at baseline and every other week. Visualization of the results suggests that the probabilistic model is suitable for real-time DPC assessment. Moreover, linear mixed model analysis and parametric bootstrapping suggest a significant intervention effect on DPC. In conclusion, these results suggest that unsupervised exergaming for improving DPC among older adults is indeed feasible and that probabilistic models could be a new approach to assess DPC. Copyright © 2017 Elsevier B.V. All rights reserved.

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

    DEFF Research Database (Denmark)

    Ruhe, A.; Fejer, R.; Walker, B.

    2011-01-01

    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......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...

  17. Precision control of an upright trunk posture in low back pain patients.

    Science.gov (United States)

    Willigenburg, Nienke W; Kingma, Idsart; van Dieën, Jaap H

    2012-11-01

    Low back pain appears to be associated with impaired trunk postural control, which could be caused by proprioceptive deficits. We assessed control of trunk posture in conditions requiring high and low precision, with and without disturbance of proprioception by lumbar muscle vibration. Twenty a-specific low back pain patients and 13 healthy controls maintained a self-chosen upright trunk posture. Initial frontal and sagittal plane angles of an opto-electronic marker on the 12th thoracic spinous process defined the center of a target area on a monitor. Subjects were instructed to stay within that target and visual feedback was provided when they left the target. The precision demand was manipulated by changing target size. The standard deviation of trunk angle quantified precision and mean Euclidian distance to target center quantified accuracy. Ratios of antagonistic co-activation were calculated from trunk muscle electromyography recordings. With the small target, visual feedback was present intermittently and patients controlled their trunk as accurately and precisely as healthy controls. For the large target, subjects mostly stayed within the target, and patients were on average 0.18° (31%) less accurate than healthy controls (P=0.025), due to a larger postural drift. Lumbar muscle vibration deteriorated control over trunk posture in both groups and ratios of antagonistic co-activation did not differ between groups or conditions. These results indicate that the weighting of proprioceptive feedback from lumbar muscle spindles did not differ between groups and that low back pain patients were less able to detect low frequency drift in posture. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Dynamic plantar pressure distribution, strength capacity and postural control after Lisfranc fracture-dislocation

    DEFF Research Database (Denmark)

    Mehlhorn, Alexander T; Walther, Markus; Yilmaz, Tayfun

    2017-01-01

    of life. 17 consecutive patients suffering from a Lisfranc fracture dislocation were registered, underwent open reduction and internal fixation and were followed-up for 50.5±25.7months (Mean±SDM). Biomechanical analysis of muscle strength capacities, postural control and plantar pressure distribution......Substantial progress has been made in the operative treatment of Lisfranc fractures, however, the prognosis remains poor. We hypothesized that Lisfranc injuries change the postural control and muscle strength of the lower limb. Both are suggested to correlate with the clinical outcome and quality...... correlated well with clinical outcome. Altered postural control was evident by a significant reduction in unilateral stance time, from which we calculated a strong correlation between stance time and the isokinetic strength measurement. Plantar pressure measurements revealed a significant reduction in peak...

  19. Evaluation of the lambda model for human postural control during ankle strategy.

    Science.gov (United States)

    Micheau, Philippe; Kron, Aymeric; Bourassa, Paul

    2003-09-01

    An accurate modeling of human stance might be helpful in assessing postural deficit. The objective of this article is to validate a mathematical postural control model for quiet standing posture. The postural dynamics is modeled in the sagittal plane as an inverted pendulum with torque applied at the ankle joint. The torque control system is represented by the physiological lambda model. Two neurophysiological command variables of the central nervous system, designated lambda and micro, establish the dynamic threshold muscle at which motoneuron recruitment begins. Kinematic data and electromyographic signals were collected on four young males in order to measure small voluntary sway and quiet standing posture. Validation of the mathematical model was achieved through comparison of the experimental and simulated results. The mathematical model allows computation of the unmeasurable neurophysiological commands lambda and micro that control the equilibrium position and stability. Furthermore, with the model it is possible to conclude that low-amplitude body sway during quiet stance is commanded by the central nervous system.

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

    Science.gov (United States)

    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.

  1. Comparison of the postural control between football players following ACL reconstruction and healthy subjects.

    Science.gov (United States)

    Pahnabi, Gholamreza; Akbari, Mohammad; Ansari, Noureddin Nakhostin; Mardani, Mahmoud; Ahmadi, Mehdi; Rostami, Mohamad

    2014-01-01

    Rupture of the Anterior Cruciate Ligment (ACL) is a common knee injury. The purpose of this study was to determine the balance control in football players with and without ACL reconstruction in posture of injury. Sway of the center of gravity of 15 patients with ACL reconstruction was compared with 15 healthy, age and sex-matched subjects as the control group. All tests were done unilaterally in the posture of injury, using a kistler force plate with the open and -closed eye conditions. The knee of the operated side of the case group showed more displacement of the center of gravity when compared to the non-operated side in the same subject for all variables of the force plate. The operated side of the case group showed more displacement of the center of gravity for all variables of the force plate in comparison with the dominant side of knees in control group. There were significant differences between the non-operated side in the case group and the dominant side of the control group. All together, postural control in the operated side of the case group was weaker than the nonoperated side of the same group and the dominant limb of the control group, which might have resulted from poor proprioception. The postural control was even weaker in the non-operated side of the case group as compared with the dominant limb of the control group, which can justify the hypo mobility of limb for several months after the surgery.

  2. Improving gross motor function and postural control with hippotherapy in children with Down syndrome: case reports.

    Science.gov (United States)

    Champagne, Danielle; Dugas, Claude

    2010-11-01

    The purpose of this case report is to describe the impact of an 11-week hippotherapy program on the gross motor functions of two children (respectively 28 and 37 months old) diagnosed with Down syndrome. Hippotherapy is a strategy that uses the horse's motion to stimulate and enhance muscle contraction and postural control. The children were assessed by the Gross Motor Function Measure (GMFM) and accelerometry. The results indicate that both children improved on many dimensions of the GMFM. Power spectral analysis of the acceleration signals showed improvement in postural control of either the head or trunk, because the children adopted two different adaptative strategies to perturbation induced by the moving horse.

  3. THE ROLE OF LEG AND TRUNK MUSCLES PROPRIOCEPTION ON STATIC AND DYNAMIC POSTURAL CONTROL

    Directory of Open Access Journals (Sweden)

    SEYED Hossein Hosseinimehr

    2010-04-01

    Full Text Available The proprioception information is a prerequisite for balance, body’s navigation system, and the movement coordinator. Due to changes between the angles of ankle, knee, and hip joints the aforementioned information are important in the coordination of the limbs and postural balance. The aim of this study was to investigate therole of leg and trunk muscles proprioception on static and dynamic postural control. Thirty males students of physical education and sport sciences (age =21.23 ± 2.95 years, height = 170.4 ± 5.1 cm, and weight = 70.7 ± 5.6 kg participated in this study volunteered. Vibration (100HZ was used to disturb of proprioception. Vibrationoperated on leg muscle (gasterocnemius and trunk muscles (erector spine muscle, at L1 level. Leg stance time and Star Excursion Balance Test were used for evaluation of static and dynamic postural control respectively.Subjects performed pre and post (with operated vibration leg stance time and star excursion balance test. Paired sample test used for investigation the effect of vibration on leg and trunk muscles in static and dynamic postural control. Result of this study showed in static postural control, there is no significant difference between pre and post test (operated vibration in leg and trunk muscles (p≤0.05. In contrast there is significant difference indynamic postural control between pre and post test in leg muscles in 8 directions of star excursion balance test (p≤0.05 while there is only significant difference in trunk muscle in antrolateral and lateral of star excursion balance test (p≤0.05. During physical training such conditions like fatigue and injury can disturbproprioceptions’ information. Thus, due to the importance of this information we recommend that coaches'additionally specific trainings any sport used specific exercises to enhance the proprioception information

  4. Components of Standing Postural Control Evaluated in Pediatric Balance Measures: A Scoping Review.

    Science.gov (United States)

    Sibley, Kathryn M; Beauchamp, Marla K; Van Ooteghem, Karen; Paterson, Marie; Wittmeier, Kristy D

    2017-10-01

    To identify measures of standing balance validated in pediatric populations, and to determine the components of postural control captured in each tool. Electronic searches of MEDLINE, Embase, and CINAHL databases using key word combinations of postural balance/equilibrium, psychometrics/reproducibility of results/predictive value of tests, and child/pediatrics; gray literature; and hand searches. Inclusion criteria were measures with a stated objective to assess balance, with pediatric (≤18y) populations, with at least 1 psychometric evaluation, with at least 1 standing task, with a standardized protocol and evaluation criteria, and published in English. Two reviewers independently identified studies for inclusion. There were 21 measures included. Two reviewers extracted descriptive characteristics, and 2 investigators independently coded components of balance in each measure using a systems perspective for postural control, an established framework for balance in pediatric populations. Components of balance evaluated in measures were underlying motor systems (100% of measures), anticipatory postural control (72%), static stability (62%), sensory integration (52%), dynamic stability (48%), functional stability limits (24%), cognitive influences (24%), verticality (9%), and reactive postural control (0%). Assessing children's balance with valid and comprehensive measures is important for ensuring development of safe mobility and independence with functional tasks. Balance measures validated in pediatric populations to date do not comprehensively assess standing postural control and omit some key components for safe mobility and independence. Existing balance measures, that have been validated in adult populations and address some of the existing gaps in pediatric measures, warrant consideration for validation in children. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

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

    Science.gov (United States)

    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.

  6. Foot placement in robotic bipedal locomotion

    NARCIS (Netherlands)

    De Boer, T.

    2012-01-01

    Human walking is remarkably robust, versatile and energy-efficient: humans have the ability to handle large unexpected disturbances, perform a wide variety of gaits and consume little energy. A bipedal walking robot that performs well on all of these aspects has not yet been developed. Some robots

  7. Effects of the cognitive tasks in the postural control of elderly: A systematic revision

    Directory of Open Access Journals (Sweden)

    Larissa Pires de Andrade

    2011-09-01

    Full Text Available Demanding attention in order to keep postural balance increases with aging and with the presence of concurrent tasks that require information processing. Several studies have demonstrated that motor performance can be related to the complexity of the task and aging process, presenting a possible interaction between these factors. The aim of this review was to identify and analyze published papers about the effects of cognitive tasks on the postural control of elderly individuals. A systematic search in the Web of Science, SportDiscus, CINAHL, Science Direct on line, Biological Abstracts, PsycINFO, and Medline databases was made and 444 articles were found. Eight were selected that studied the variables of interest. These studies showed that postural control seems to be influenced by the individual's attention processes and that deficits in such ability may be associated to an increased risk of falls.

  8. Controle postural em indivíduos portadores da síndrome de Down: revisão de literatura Postural control in individuals with Down syndrome: a review

    Directory of Open Access Journals (Sweden)

    Regiane Luz Carvalho

    2008-09-01

    Full Text Available Este trabalho consistiu numa revisão da literatura sobre controle postural em indivíduos portadores da síndrome de Down, por meio de consulta às bases de dados Medline, Lilacs e Web of Science. Dentre os artigos publicados nos últimos 16 anos, selecionaram-se 30, dos quais 7 focalizam a natureza dos défices no sistema de controle postural, como alterações neurobiológicas e biomecânicas, e 23 enfocam o controle postural no período de desenvolvimento (11 artigos e em adolescentes e adultos (12 artigos portadores da síndrome. Discutem-se os marcos teóricos que conformam a compreensão do desenvolvimento postural e seus défices, bem como as implicações dessa compreensão para a prática da fisioterapia.This is a review of literature on postural control in individuals with the Down syndrome, by searching in Medline, Lilacs and Web of Science data bases. Among articles published in the last 16 years, 30 were selected, of which 7 focus on postural control system deficits, such as neurobiological and biomechanical alterations, and 23 focus postural control development (11 articles and in adolescents and adults (12 articles with the Down syndrome. The theoretic bases for understanding posture control development and deficits are discussed, in view of their implications for physical therapy practice.

  9. The upright posture improves plantar stepping and alters responses to serotonergic drugs in spinal rats

    Science.gov (United States)

    Sławińska, Urszula; Majczyński, Henryk; Dai, Yue; Jordan, Larry M

    2012-01-01

    Recent studies on the restoration of locomotion after spinal cord injury have employed robotic means of positioning rats above a treadmill such that the animals are held in an upright posture and engage in bipedal locomotor activity. However, the impact of the upright posture alone, which alters hindlimb loading, an important variable in locomotor control, has not been examined. Here we compared the locomotor capabilities of chronic spinal rats when placed in the horizontal and upright postures. Hindlimb locomotor movements induced by exteroceptive stimulation (tail pinching) were monitored with video and EMG recordings. We found that the upright posture alone significantly improved plantar stepping. Locomotor trials using anaesthesia of the paws and air stepping demonstrated that the cutaneous receptors of the paws are responsible for the improved plantar stepping observed when the animals are placed in the upright posture. We also tested the effectiveness of serotonergic drugs that facilitate locomotor activity in spinal rats in both the horizontal and upright postures. Quipazine and (±)-8-hydroxy-2-(dipropylamino)tetralin hydrobromide (8-OH-DPAT) improved locomotion in the horizontal posture but in the upright posture either interfered with or had no effect on plantar walking. Combined treatment with quipazine and 8-OH-DPAT at lower doses dramatically improved locomotor activity in both postures and mitigated the need to activate the locomotor CPG with exteroceptive stimulation. Our results suggest that afferent input from the paw facilitates the spinal CPG for locomotion. These potent effects of afferent input from the paw should be taken into account when interpreting the results obtained with rats in an upright posture and when designing interventions for restoration of locomotion after spinal cord injury. PMID:22351637

  10. Exercise interventions improve postural control in children with cerebral palsy: a systematic review.

    Science.gov (United States)

    Dewar, Rosalee; Love, Sarah; Johnston, Leanne Marie

    2015-06-01

    The aim of this study was to evaluate the efficacy and effectiveness of exercise interventions that may improve postural control in children with cerebral palsy (CP). A systematic review was performed using American Academy of Cerebral Palsy and Developmental Medicine (AACPDM) and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology. Six databases were searched using the following keywords: ('cerebral palsy' OR 'brain injury'); AND ('postur*' OR 'balance' OR 'postural balance' [MeSH]); AND ('intervention' OR 'therapy' OR 'exercise' OR 'treatment'). Articles were evaluated based on their level of evidence and conduct. Searches yielded 45 studies reporting 13 exercise interventions with postural control outcomes for children with CP. Five interventions were supported by a moderate level of evidence: gross motor task training, hippotherapy, treadmill training with no body weight support (no-BWS), trunk-targeted training, and reactive balance training. Six of the interventions had weak or conflicting evidence: functional electrical stimulation (FES), hippotherapy simulators, neurodevelopmental therapy (NDT), treadmill training with body weight support, virtual reality, and visual biofeedback. Progressive resistance exercise was an ineffective intervention, and upper limb interventions lacked high-level evidence. The use of exercise-based treatments to improve postural control in children with CP has increased significantly in the last decade. Improved study design provides more clarity regarding broad treatment efficacy. Research is required to establish links between postural control impairments, treatment options, and outcome measures. Low-burden, low-cost, child-engaging, and mainstream interventions also need to be explored. © 2014 Mac Keith Press.

  11. Impaired postural control in children with developmental coordination disorder is related to less efficient central as well as peripheral control

    DEFF Research Database (Denmark)

    Speedtsberg, Merete Brink; Christensen, Sofie Bouschinger; Andersen, Ken Kjøller

    2017-01-01

    BACKGROUND: Developmental coordination disorder (DCD) is a neurodevelopmental impairment that affects approximately 6% of children in primary school age. Children with DCD are characterized by impaired postural control. It has yet to be determined what effect peripheral and central neuromuscular...... control has on their balance control. OBJECTIVE: The aim of this study was to investigate the underlying mechanisms to impaired postural control in children with DCD using the rambling-trembling decomposition of the center of pressure (CoP). METHOD: Nine children with DCD (9.0±0.5years, 7 boys, 2 girls...... with fixed support surface. In ML direction children with DCD had a lower relative contribution of rambling to total sway (p=0.013). CONCLUSION: This study showed that impaired postural control in children with DCD is associated with less efficient supraspinal control represented by increased rambling...

  12. Postural control analysis of diabetic individuals through baropodometry

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    Andréa Jeanne Lourenço Nozabieli

    2012-10-01

    Full Text Available Objective of this study was to analyze the postural balance of neuropathic diabetic individuals through baropodometry, related to losses in the sensorimotor system. Twenty-eight healthy and 25 diagnosed with diabetic neuropathy were subjected to static evaluation (measurement of displacement of body center of pressure and dynamic (temporal analysis of the stance phase of gait cycle. The tactile sensitivity of the feet was assessed by Semmes Weinstein monofilaments and isometric muscle strength of ankle dynamometry. Analyses of multivariânvia (MANOVAs and variance (ANOVAs indicated lower performance in tactile sensitivity, muscle strength and dynamic balance, but showed no difference for static equilibrium of diabetic neuropathy. With this study by regression analysis, one can infer that the equilibrium differences in gait of neuropathic insensitivity may result from tactile and muscle strength.

  13. Steroid-associated hip joint collapse in bipedal emus.

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    Li-Zhen Zheng

    Full Text Available In this study we established a bipedal animal model of steroid-associated hip joint collapse in emus for testing potential treatment protocols to be developed for prevention of steroid-associated joint collapse in preclinical settings. Five adult male emus were treated with a steroid-associated osteonecrosis (SAON induction protocol using combination of pulsed lipopolysaccharide (LPS and methylprednisolone (MPS. Additional three emus were used as normal control. Post-induction, emu gait was observed, magnetic resonance imaging (MRI was performed, and blood was collected for routine examination, including testing blood coagulation and lipid metabolism. Emus were sacrificed at week 24 post-induction, bilateral femora were collected for micro-computed tomography (micro-CT and histological analysis. Asymmetric limping gait and abnormal MRI signals were found in steroid-treated emus. SAON was found in all emus with a joint collapse incidence of 70%. The percentage of neutrophils (Neut % and parameters on lipid metabolism significantly increased after induction. Micro-CT revealed structure deterioration of subchondral trabecular bone. Histomorphometry showed larger fat cell fraction and size, thinning of subchondral plate and cartilage layer, smaller osteoblast perimeter percentage and less blood vessels distributed at collapsed region in SAON group as compared with the normal controls. Scanning electron microscope (SEM showed poor mineral matrix and more osteo-lacunae outline in the collapsed region in SAON group. The combination of pulsed LPS and MPS developed in the current study was safe and effective to induce SAON and deterioration of subchondral bone in bipedal emus with subsequent femoral head collapse, a typical clinical feature observed in patients under pulsed steroid treatment. In conclusion, bipedal emus could be used as an effective preclinical experimental model to evaluate potential treatment protocols to be developed for prevention of

  14. Steroid-Associated Hip Joint Collapse in Bipedal Emus

    Science.gov (United States)

    Zheng, Li-Zhen; Liu, Zhong; Lei, Ming; Peng, Jiang; He, Yi-Xin; Xie, Xin-Hui; Man, Chi-Wai; Huang, Le; Wang, Xin-Luan; Fong, Daniel Tik-Pui; Xiao, De-Ming; Wang, Da-Ping; Chen, Yang; Feng, Jian Q.; Liu, Ying; Zhang, Ge; Qin, Ling

    2013-01-01

    In this study we established a bipedal animal model of steroid-associated hip joint collapse in emus for testing potential treatment protocols to be developed for prevention of steroid-associated joint collapse in preclinical settings. Five adult male emus were treated with a steroid-associated osteonecrosis (SAON) induction protocol using combination of pulsed lipopolysaccharide (LPS) and methylprednisolone (MPS). Additional three emus were used as normal control. Post-induction, emu gait was observed, magnetic resonance imaging (MRI) was performed, and blood was collected for routine examination, including testing blood coagulation and lipid metabolism. Emus were sacrificed at week 24 post-induction, bilateral femora were collected for micro-computed tomography (micro-CT) and histological analysis. Asymmetric limping gait and abnormal MRI signals were found in steroid-treated emus. SAON was found in all emus with a joint collapse incidence of 70%. The percentage of neutrophils (Neut %) and parameters on lipid metabolism significantly increased after induction. Micro-CT revealed structure deterioration of subchondral trabecular bone. Histomorphometry showed larger fat cell fraction and size, thinning of subchondral plate and cartilage layer, smaller osteoblast perimeter percentage and less blood vessels distributed at collapsed region in SAON group as compared with the normal controls. Scanning electron microscope (SEM) showed poor mineral matrix and more osteo-lacunae outline in the collapsed region in SAON group. The combination of pulsed LPS and MPS developed in the current study was safe and effective to induce SAON and deterioration of subchondral bone in bipedal emus with subsequent femoral head collapse, a typical clinical feature observed in patients under pulsed steroid treatment. In conclusion, bipedal emus could be used as an effective preclinical experimental model to evaluate potential treatment protocols to be developed for prevention of ON

  15. Age-related effects of a memorizing spatial task in the adults and elderly postural control.

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    Berger, Laetitia; Bernard-Demanze, Laurence

    2011-02-01

    The aim of this study was to evaluate the age-related changes in postural control during a simple quiet standing task and a dual-task paradigm (applying a memory-spatial task and quiet standing). Thirty-five subjects were divided in two age-related groups: both younger (Y: 20-26 years) and older (O: 60-77 years) groups performed a simple postural task (quiet standing) and a dual-task (a visual memory task combined with quiet standing). Measures of the center of pressure (CoP) were recorded and its two components, the center of gravity (CG) and the differential CoP-CG, were evaluated. An age-related effect was observed in static postural performance during dual-tasking. Postural stability led to improved performance in younger subjects during the dual-task and but not in the elderly. Of the results suggest there is a "cognition first" principle for the younger adults, that is, the mirror image of the "posture first" principle observed in older adults under dual-tasking situations. Copyright © 2010 Elsevier B.V. All rights reserved.

  16. Feasibility of closed-loop controller for righting seated posture after spinal cord injury.

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    Murphy, Julie O; Audu, Musa L; Lombardo, Lisa M; Foglyano, Kevin M; Triolo, Ronald J

    2014-01-01

    Spinal cord injury (SCI) can compromise the ability to maintain an erect seated posture. This study examined the feasibility of a sensor-based threshold controller to automatically modulate stimulation to paralyzed hip and trunk extensor muscles to restore upright sitting from forward leaning postures. Forward trunk tilt was estimated from the anterior-posterior component of gravitational acceleration sensed by a sternum-mounted wireless accelerometer. Stimulation increased if trunk tilt exceeded a specified flexion threshold and ceased once upright sitting was resumed. The controller was verified experimentally in five volunteers with SCI and successfully returned all subjects to upright postures from forward leaning positions. Upper-limb effort exerted while returning to erect posture was significantly reduced (to 7.4% +/- 3.7% of body mass) pooled across all volunteers while using the controller compared with using continuous and no stimulation (p Controller response times were consistent among subjects when applied while sitting with (0.30 +/- 0.05 s) or without a backrest (0.34 +/- 0.11 s). The controller enabled volunteers to lean farther forward (59.7° +/- 16.4°) in wheelchairs without upper-limb effort than with no stimulation. Clinical utility of the system for facilitating reach or preventing falls remains to be determined in future studies.

  17. Posture and body image in individuals with major depressive disorder: a controlled study.

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    Canales, Janette Zamudio; Cordás, Táki Athanássios; Fiquer, Juliana Teixeira; Cavalcante, André Furtado; Moreno, Ricardo Alberto

    2010-12-01

    In this study, we aimed to quantify posture and body image in patients with major depressive disorder during episodes and after drug treatment, comparing the results with those obtained for healthy volunteers. Over a 10-week period, we evaluated 34 individuals with depression and 37 healthy volunteers. Posture was assessed based on digital photos of the subjects; CorelDRAW software guidelines and body landmarks were employed. Body image was evaluated using the Body Shape Questionnaire. During depressive episodes (in comparison with the post-treatment period), patients showed increased head flexion (pBody Shape Questionnaire was 90.03 during the depressive episode, compared with 75.82 during remission (p=0.012) and 62.57 for the controls. During episodes of depression, individuals with major depressive disorder experience changes in posture and mild dissatisfaction with body image. The findings demonstrate that the negative impact of depression includes emotional and physical factors.

  18. The Comparison of Postural Control Ability in Children with/without Dyslexia

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    Morteza Arghiani

    2013-04-01

    Full Text Available Objective: In some reviewed studies on children with dyslexia it is observed that there is a significant relationship between the ability of postural control and dyslexia. In this study, by controlling the interfering factors, we have reviewed this relation by comparing postural control and balance ability in normal and dyslexic children. Materials & Methods: This case-control study is done on 19 boys with dyslexia (112.90±13.78 and 19 Normal boys (118.42±15.62. Normal children and children with dyslexia were matched in age, height and weight. Positioning duties included standing with adjacent feet on firm surface with open and closed eyes, and with close eyes on the foam and with internal perturbation on firm surface. Duration of each assignment was 35 seconds and the force plate device was used to evaluate the condition performance. Balances component of Bruininks Oseretsky test were take from all of the samples and correlation between functional and laboratory test were examined. Results: The results showed that the area on firm surface with open eyes, internal perturbation dependency rate in the standard deviations of the lateral body sways (SDX and of the antero-posterior body sways (SDY and the surface area, there were significant differences between normal and dyslexic children, but there was not any significant difference between the two groups in path length and mean velocity in different postural control modes (foam, firm surface, open and close eyes and visual dependence in all parameters (path length, velocity and surface area. We did not find significant correlation between Center of Pressure (COP and the balance part of Bruininks Oseretsky test in children with dyslexia. Conclusion: In spite of differences in some postural control parameters between normal group and children with dyslexia, it was not found significant relationship between postural control and dyslexia.

  19. Reproducibility of postural control measurement during unstable sitting in low back pain patients

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    Duquet William

    2007-05-01

    Full Text Available Abstract Background Postural control tests like standing and sitting stabilometry are widely used to evaluate neuromuscular control related to trunk balance in low back pain patients. Chronic low back pain patients have lesser postural control compared to healthy subjects. Few studies have assessed the reproducibility of the centre of pressure deviations and to our knowledge no studies have investigated the reproducibility of three-dimensional kinematics of postural control tests in a low back pain population. Therefore the aim of this study was to assess the test-retest reproducibility of a seated postural control test in low back pain patients. Methods Postural control in low back pain patients was registered by a three dimensional motion analysis system combined with a force plate. Sixteen chronic low back pain patients having complaints for at least six months, were included based on specific clinical criteria. Every subject performed 4 postural control tests. Every test was repeated 4 times and lasted 40 seconds. The force plate registered the deviations of the centre of pressure. A Vicon-612-datastation, equipped with 7 infra-red M1 camera's, was used to track 13 markers attached to the torso and pelvis in order to estimate their angular displacement in the 3 cardinal planes. Results All Intraclass Correlation Coefficients (ICC calculated for the force plate variables did not exceed 0.73 (ranging between 0.11 and 0.73. As for the torso, ICC's of the mean flexion-extension and rotation angles ranged from 0.65 to 0.93 and of the mean lateral flexion angle from 0.50 to 0.67. For the pelvis the ICC of the mean flexion-extension angle varied between 0.66 and 0.83, the mean lateral flexion angle between 0.16 and 0.81 and the mean rotation angle between 0.40 and 0.62. Consecutive data suggest that the low test-retest reproducibility is probably due to a learning effect. Conclusion The test-retest reproducibility of these postural control tests in

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

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    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.

  1. Effect of seat surface inclination on postural control during reaching in preterm children with cerebral palsy

    NARCIS (Netherlands)

    Hadders-Algra, Mijna; van der Heide, Jolanda C.; Fock, Johanna M.; Stremmelaar, Elisabeth; van Eykern, Leo A.; Otten, Bert

    Background and Purpose Because it is debatable whether seat surface inclination improves motor function in children with cerebral palsy (CP), the effect of seat surface tilting on postural control and quality of reaching was studied. Subjects The subjects were 58 children with CP aged 2 to 11 years

  2. Postural Control in Young People with Visual Impairments and Various Risks of Falls

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    Sadowska, Dorota; Stemplewski, Rafal; Szeklicki, Robert

    2017-01-01

    Introduction: Early diagnosis of postural control deficiencies facilitates implementation of an individual rehabilitation plan to prevent falls. The aim of the study was to assess the risk of falling in individuals with visual impairments, and to compare performance-based and theoretical limits of stability in subjects with various risks of…

  3. Real-time visual feedback of COM and COP motion properties differentially modifies postural control structures.

    Science.gov (United States)

    Kilby, Melissa C; Molenaar, Peter C M; Slobounov, Semyon M; Newell, Karl M

    2017-01-01

    The experiment was setup to investigate the control of human quiet standing through the manipulation of augmented visual information feedback of selective properties of the motion of two primary variables in postural control: center of pressure (COP) and center of mass (COM). Five properties of feedback information were contrasted to a no feedback dual-task (watching a movie) control condition to determine the impact of visual real-time feedback on the coordination of the joint motions in postural control in both static and dynamic one-leg standing postures. The feedback information included 2D COP or COM position and macro variables derived from the COP and COM motions, namely virtual time-to-contact (VTC) and the COP-COM coupling. The findings in the static condition showed that the VTC and COP-COM coupling feedback conditions decreased postural motion more than the 2D COP or COM positional information. These variables also induced larger sway amplitudes in the dynamic condition showing a more progressive search strategy in exploring the stability limits. Canonical correlation analysis (CCA) found that COP-COM coupling contributed less than the other feedback variables to the redundancy of the system reflected in the common variance between joint motions and properties of sway motion. The COP-COM coupling had the lowest weighting of the motion properties to redundancy under the feedback conditions but overall the qualitative pattern of the joint motion structures was preserved within the respective static and dynamic balance conditions.

  4. Postural control in children with spastic diplegia : Muscle activity during perturbations in sitting

    NARCIS (Netherlands)

    Brogren, E; HaddersAlgra, M; Forssberg, H

    To clarify the neural mechanisms controlling equilibrium during sitting, and the implications for the optimal sitting position for children with CP, automatic postural adjustments after perturbations of the support surface during sitting were investigated in seven children with spastic diplegia and

  5. Effects of plantar foot sensitivity manipulation on postural control of young adult and elderly

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    Álvaro S. Machado

    Full Text Available ABSTRACT Introduction: Subjects with sensorial losses present balance deficits. Although such condition is often observed among elderly, there is discussion concerning the dependence on sensorial information for body sway control in the elderly without sensorial losses. Purpose: We investigated the effects of foot sensitivity manipulation on postural control during upright standing in young adults and independent elderly (n = 19/group. Methods: Plantar sensitivity was evaluated by esthesiometry, and speed of center of pressure shift data during upright posture were evaluated for each foot using a baropodometer while the subjects were standing with eyes open or closed. The young adult group was evaluated for center of pressure in normal conditions and after plantar sensitivity disturbance, by immersing their feet in water and ice. Results: Young adults did not show alterations in their center of pressure after sensorial perturbation and presented, even under sensorial perturbation, better postural control than elderly subjects. The elderly showed lower foot sensitivity and greater center of pressure oscillation than young adults. Conclusion: Elderly subjects seem to rely more on foot sensitivity for control of body sway than young adults. In the elderly, a clinical intervention to improve foot sensitivity may help in upright posture maintenance.

  6. Process Control/SCADA system vendor security awareness and security posture.

    NARCIS (Netherlands)

    Luiijf, H.A.M.; Lüders, S.

    2009-01-01

    A starting point for the adequate security of process control/SCADA systems is the security awareness and security posture by the manufacturers, vendors, system integrators, and service organisations. The results of a short set of questions indicate that major security improvements are required in

  7. The Effect of Fatigue in Proxmal and Distal Muscles of Lower Extremity on Postural Control

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    Mozhgan Moghadam

    2003-07-01

    Full Text Available Objective: Several studies have shown the effects of muscular fatigue on proprioception and neuromuscular control. However all available researches have studied just the effect of local fatigue in ankle joint muscles on postural control, and no study have found about the effect of fatigue in proximal muscles of the lower extremity on postural control. To compare changes in postural control parameters after isokinetic fatigue of proximal and distal muscles of lower extremity. Materials & Methods: Subjects were twenty healthy men (age: 22.6±2.4 years, height: 173.7± 3.6 cm, weight: 63.3±7.9kg. There were 4 test sessions, with a randomized order according to site and plane of fatigue. During each session one of these muscle groups was fatigued using a Biodex isokinetic dynamometer: ankle plantar / dorsi flexors, ankle evertor / inventors, hip flexor / extensors and hip abductor/adductors. The biodex stability system was used to perform dynamic balance test before and after muscle fatigue in each session. Overall, anterior / posterior, and medial/lateral stability indices were recorded. The higher the stability indices, the lower the balancing skill. Results: Analysis of pre-and post fatigue balance results of all sessions, demonstrated significant increase (P<0.05 in all stability indices. Repeated measures ANOVA performed on the rate of changes in stability indices during each session revealed that hip muscle fatigue caused much more increase in stability indices than ankle muscle fatigue (P<0.05. Conclusion: Isokinetic fatigue of both ankle and hip muscles significantly decreases postural control ability in healthy young men. In addition, our findings suggest that the hip joint musculature plays a more prominent role in postural control.

  8. Delayed postural control during self-generated perturbations in the frail older adults

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    Kubicki, Alexandre; Bonnetblanc, François; Petrement, Geoffroy; Ballay, Yves; Mourey, France

    2012-01-01

    Purpose The aim of this study was to investigate the coordination between posture and movement in pathological aging (frailty) in comparison with normal aging, with the hypothesis that in pathological aging, postural control evolves towards a more reactive mode for which the perturbation induced by the movement is not anticipated and leads to delayed and late postural adjustments. Methods Elderly subjects performed rapid focal arm-raising movements towards a target, from an upright standing position in two stimuli conditions: simple reaction time and choice reaction time (CRT). Hand and center of pressure (CoP) kinematics were compared between a control group and a frail group of the same age. Results In frail individuals, the entire movement was impaired and slowed down. In addition, postural adjustments that classically precede and accompany the focal arm movement were delayed and reduced, especially in the CRT condition in which the motor prediction is more limited. Finally, a correlation between the time to CoP maximal velocity and the timed up- and-go score was observed. Conclusion In these patients, it was concluded that the control of the CoP displacement evolved from a proactive mode in which the perturbation associated with the arm movement is anticipated toward a more reactive mode in which the perturbation is compensated by late and delayed adjustments. PMID:22423179

  9. Influence of prolonged wearing of unstable shoes on upright standing postural control.

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    Sousa, Andreia S P; Macedo, Rui; Santos, Rubim; Sousa, Filipa; Silva, Andreia; Tavares, João Manuel R S

    2016-02-01

    To study the influence of prolonged wearing of unstable shoes on standing postural control in prolonged standing workers. The participants were divided into two groups: one wore unstable shoes while the other wore conventional shoes for 8weeks. Stabilometry parameters related to centre of pressure (CoP), rambling (RM) and trembling (TR) as well as the total agonist/antagonist muscle activity, antagonist co-activation and reciprocal activation were evaluated during upright standing, before and after the 8weeks period. In both moments, the subjects were evaluated wearing the unstable shoes and in barefoot. The unstable shoe condition presented increased CoP displacement related variables and decreased co-activation command compared to barefoot before and after the intervention. The prolonged wearing of unstable shoes led to: (1) reduction of medial-lateral CoP root mean square and area; (2) decreased anteroposterior RM displacement; (3) increased anteroposterior RM mean velocity and mediolateral RM displacement; (4) decreased anteroposterior TR RMS; and (5) increased thigh antagonist co-activation in the unstable shoe condition. The unstable shoe condition is associated to a higher destabilising effect that leads to a selection of more efficient and accurate postural commands compared to barefoot. Prolonged wearing of unstable shoes provides increased effectiveness and performance of the postural control system, while wearing of unstable shoes in upright standing, that are reflected by changes in CoP related variables and by a reorganisation of postural control commands. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Tool Posture Determination for 5-Axis Control Machining by Area Division Method

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    Umehara, Takeshi; Teramoto, Koji; Ishida, Tohru; Takeuchi, Yoshimi

    The study deals with a new method to generate interference-free tool posture for 5-axis control machining using a ball end-mill. The 5-axis control machining can produce complicated shapes and parts consisting of overhanging and or sculptured surfaces such as impellers. However, high degree of freedom of 5-axis control machining center causes a fatal problem that other parts except cutting edges of the tool may interfere with other surfaces of the machining object. Therefore, it is necessary to obtain the adequate tool postures to avoid the interference during machining. The interference avoidance is generally performed by the method that cutting points are generated so as to be arranged on the surface to be machined, and then the interference-free tool posture is determined on each cutting point by the geometrical calculations. However, the method has a problem that it takes long time for calculation. To solve the problem, the study proposes a new interference avoidance method of reversing the order of the above procedure, i.e., that of determining a set of interference-free tool postures before generating cutting points. From the machining results, it is confirmed that the proposed method is available to fabricate complicated shapes since the impeller can be machined by using the method.

  11. Effect of Dominant Versus Non-dominant Vision in Postural Control.

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    Park, Rae-Young; Kee, Hoi-Sung; Kang, Jung-Ho; Lee, Su-Jin; Yoon, Soe-Ra; Jung, Kwang-Ik

    2011-06-01

    To assess the effect of dominant and non-dominant vision in controlling posture in quiet stance. Twenty-five healthy elderly subjects aged over 60 years old and twenty-five young subjects aged under 30 years old were assessed by computerized dynamic posturography. Postural stability was measured in two conditions; dominant eye open and non-dominant eye open. We used the sensory organization test (SOT) for evaluating sensory impairment. A SOT assessed the subject's ability to use and integrate somatosensory input, vision, and vestibular cues effectively to maintain balance. The SOT was conducted 3 times, and the average value of the 3 trials was used for data analysis. Equilibrium scores reflected the subject's anteroposterior sway. The highest possible score was 100, which indicated that the subject did not sway at all, and a score of 0 indicated a fall from the footplate. Determination of ocular dominance was performed by a hole-in-the card test. For the twenty-five young subjects in this study, equilibrium score in two conditions did not differ. However, for elderly subjects over 60 years, the equilibrium score in dominant vision was higher than in nondominant vision (p<0.05). In young subjects, there were no significant differences in postural control between dominant vision and non-dominant vision. However, in elderly subjects, postural control in non-dominant vision was significantly impaired. Therefore, the evaluation of a dominant eye should be considered in rehabilitation programs for elderly people.

  12. Analysis of postural control and muscular performance in young and elderly women in different age groups

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    Matheus M. Gomes

    2015-02-01

    Full Text Available BACKGROUND: muscle strength and power are two factors affecting balance. The impact of muscle strength and power on postural control has not been fully explored among different age strata over sixty. OBJECTIVES: the aim of the present study was to assess the muscle strength and power of elderly women in different age groups and determine their correlation with postural control. METHOD: eighty women were divided into four groups: the young 18-30 age group (n=20; the 60-64 age group (n=20; the 65-69 age group (n=20; and the 70-74 age group (n=20. The participants underwent maximum strength (one repetition maximum or 1-RM and muscle power tests to assess the knee extensor and flexor muscles at 40%, 70%, and 90% 1-RM intensity. The time required by participants to recover their balance after disturbing their base of support was also assessed. RESULTS: the elderly women in the 60-64, 65-69, and 70-74 age groups exhibited similar muscle strength, power, and postural control (p>0.05; however, these values were lower than those of the young group (p<0.05 as expected. There was a correlation between muscle strength and power and the postural control performance (p<0.05. CONCLUSION: despite the age difference, elderly women aged 60 to 74 years exhibited similar abilities to generate strength and power with their lower limbs, and this ability could be one factor that explains the similar postural control shown by these women.

  13. The Effects of Sex, Limb Dominance, and Soccer Participation on Knee Proprioception and Dynamic Postural Control.

    Science.gov (United States)

    Cug, Mutlu; Wikstrom, Erik A; Golshaei, Bahman; Kirazci, Sadettin

    2016-02-01

    Both female athletes' participation in soccer and associated injuries have greatly increased in recent years. One issue is the 2-9 times greater incidence of noncontact anterior cruciate ligament (ACL) injuries in female athletes relative to male athletes in comparable sports. Several factors such as limb dominance and sporting history have been proposed to play a role in ACL incidence rates between male and female athletes. However, evidence about the effects of these factors and how they interact with sex is mixed, and thus no consensus exists. To quantify the effects of sports participation, limb dominance, and sex on dynamic postural control and knee-joint proprioception. Cross-sectional study. University research laboratory. 19 male soccer players, 17 female soccer players, 19 sedentary men, and 18 sedentary women. Joint-position sense was tested using reproduction of passive positioning on a Biodex isokinetic dynamometer (30°, 45°, and 60° from 90° of knee flexion). Three Star Excursion Balance Test directions were used to assess dynamic postural control. Normalized reach distance (% of leg length) in the anterior, posteromedial, and posterolateral directions on each leg quantified dynamic postural control. Average absolute error and constant error for both limbs quantified joint-position sense. Posteromedial reach distance was significantly better in soccer players than sedentary individuals (P = .006). Anterior reach distance was significantly better (P = .04) in sedentary individuals than soccer players. No limb-dominance or sex differences were identified for dynamic postural control, and no differences in absolute- or constant-error scores were identified. Sporting history has a direction-specific impact on dynamic postural control. Sporting history, sex, and limb dominance do not influence knee-joint proprioception when tested in an open kinetic chain using passive repositioning.

  14. Relationship between static postural control and the level of functional abilities in children with cerebral palsy

    Science.gov (United States)

    Pavão, Sílvia L.; Nunes, Gabriela S.; Santos, Adriana N.; Rocha, Nelci A. C. F.

    2014-01-01

    Background: Postural control deficits can impair functional performance in children with cerebral palsy (CP) in daily living activities. Objective: To verify the relationship between standing static postural control and the functional ability level in children with CP. Method: The postural control of 10 children with CP (gross motor function levels I and II) was evaluated during static standing on a force platform for 30 seconds. The analyzed variables were the anteroposterior (AP) and mediolateral (ML) displacement of the center of pressure (CoP) and the area and velocity of the CoP oscillation. The functional abilities were evaluated using the mean Pediatric Evaluation of Disability Inventory (PEDI) scores, which evaluated self-care, mobility and social function in the domains of functional abilities and caregiver assistance. Results: Spearman's correlation test found a relationship between postural control and functional abilities. The results showed a strong negative correlation between the variables of ML displacement of CoP, the area and velocity of the CoP oscillation and the PEDI scores in the self-care and caregiver assistance domains. Additionally, a moderate negative correlation was found between the area of the CoP oscillation and the mobility scores in the caregiver assistance domain. We used a significance level of 5% (p <0.05). Conclusions: We observed that children with cerebral palsy with high CoP oscillation values had lower caregiver assistance scores for activities of daily living (ADL) and consequently higher levels of caregiver dependence. These results demonstrate the repercussions of impairments to the body structure and function in terms of the activity levels of children with CP such that postural control impairments in these children lead to higher requirements for caregiver assistance. PMID:25054383

  15. Comparative Anatomy of the Hind Limb Vessels of the Bearded Capuchins (Sapajus libidinosus with Apes, Baboons, and Cebus capucinus: With Comments on the Vessels' Role in Bipedalism

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    Roqueline A. G. M. F. Aversi-Ferreira

    2013-01-01

    Full Text Available Capuchin monkeys are known to exhibit sporadic bipedalism while performing specific tasks, such as cracking nuts. The bipedal posture and locomotion cause an increase in the metabolic cost and therefore increased blood supply to lower limbs is necessary. Here, we present a detailed anatomical description of the capuchin arteries and veins of the pelvic limb of Sapajus libidinosus in comparison with other primates. The arterial pattern of the bearded capuchin hind limb is more similar to other quadrupedal Cebus species. Similarities were also found to the pattern observed in the quadruped Papio, which is probably due to a comparable pelvis and the presence of the tail. Sapajus' traits show fewer similarities when compared to great apes and modern humans. Moreover, the bearded capuchin showed unique patterns for the femoral and the short saphenous veins. Although this species switches easily from quadrupedal to bipedal postures, our results indicate that the bearded capuchin has no specific or differential features that support extended bipedal posture and locomotion. Thus, the explanation for the behavioral differences found among capuchin genera probably includes other aspects of their physiology.

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

    Directory of Open Access Journals (Sweden)

    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

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

    Science.gov (United States)

    Dupuy, Emma G.; Leconte, Pascale; Vlamynck, Elodie; Sultan, Audrey; Chesneau, Christophe; Denise, Pierre; Besnard, Stéphane; Bienvenu, Boris; Decker, Leslie M.

    2017-01-01

    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

  18. Assisting People with Multiple Disabilities Actively Correct Abnormal Standing Posture with a Nintendo Wii Balance Board through Controlling Environmental Stimulation

    Science.gov (United States)

    Shih, Ching-Hsiang; Shih, Ching-Tien; Chu, Chiung-Ling

    2010-01-01

    The latest researches adopted software technology turning the Nintendo Wii Balance Board into a high performance change of standing posture (CSP) detector, and assessed whether two persons with multiple disabilities would be able to control environmental stimulation using body swing (changing standing posture). This study extends Wii Balance Board…

  19. Postural changes in women with chronic pelvic pain: a case control study

    Directory of Open Access Journals (Sweden)

    Nogueira Antonio A

    2009-07-01

    Full Text Available Abstract Background Chronic pelvic pain (CPP is a lower abdominal pain lasting at least 6 months, occurring continuously or intermittently and not associated exclusively with menstruation or intercourse. Although the musculoskeletal system has been found to be involved in CPP, few studies have assessed the contribution of posture in women with CPP. We aimed to determine if the frequency of postural changes was higher in women with CPP than healthy subjects. Methods A case-control study included 108 women with CPP of more than 6 months' duration (CPP group who consecutively attended at the Hospital of the University of São Paulo and 48 healthy female volunteers (control group. Postural assessment was noninvasive and performed in the standing position, with the reference points of Kendall used as normal parameters. Factors associated with CPP were assessed by logistic regression analysis. Results Logistic regression showed that the independent factors associated with CPP were postural changes in the cervical spine (OR 4.1; 95% CI 1.6–10.7; p Conclusion Musculoskeletal changes were associated with CPP in 34% of women. These findings suggest that a more detailed assessment of women with CPP is necessary for better diagnosis and for more effective treatment.

  20. Dominant foot could affect the postural control in vestibular neuritis perceived by dynamic body balance.

    Science.gov (United States)

    Yoshida, Tomoe; Tanaka, Toshitake; Tamura, Yuya; Yamamoto, Masahiko; Suzuki, Mitsuya

    2018-01-01

    During attacks of vestibular neuritis (VN), patients typically lose postural balance, with resultant postural inclination, gait deviation toward the lesion side, and tendency to fall. In this study, we examined and analyzed static and dynamic postural control during attacks of VN to characterize differences in postural control between right and left VN. Subjects were patients diagnosed with VN at the Department of Otolaryngology, Toho University Sakura Medical Center, and underwent in-patient treatment. Twenty-five patients who had spontaneous nystagmus were assessed within 3days after the onset; all were right-foot dominant. Right VN was detected in nine patients (men: 4, women: 5; mean age: 57.6±17.08years [range: 23-82]) and left VN in 16 patients (men: 10, women: 6; mean age: 58.4±14.08years [range: 23-85 years]); the percentages of canal paresis of right and left VN were 86.88±18.1% and 86.02±15.0%, respectively. Statistical comparisons were conducted using the independent t-test. In stabilometry, with eyes opened, no significant differences were found between patients with right and left VN. However, with eyes closed, the center of horizontal movement significantly shifted ipsilateral (p<0.01). The differences in the lateral and anteroposterior body tracking test (BTT) were statistically significant (p=0.0039 and p=0.0376, respectively), with greater changes in cases with right VN. Thus, the dominant foot might contribute to the postural control mechanism. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Delayed postural control during self-generated perturbations in the frail older adults

    Directory of Open Access Journals (Sweden)

    Kubicki A

    2012-02-01

    Full Text Available Alexandre Kubicki1–3, François Bonnetblanc1,2, Geoffroy Petrement3, Yves Ballay1,2, France Mourey2,4¹UFR STAPS, Université de Bourgogne, Dijon, France; ²Motricité et Plasticité, Institut National de la Santé et de la Recherche Médicale (INSERM, Dijon, France; ³SARL Fovea Interactive, Campus Industriel – Espace Entreprises, Chalon sur Saône, France; 4UFR Médecine, Université de Bourgogne, Dijon, FrancePurpose: The aim of this study was to investigate the coordination between posture and movement in pathological aging (frailty in comparison with normal aging, with the hypothesis that in pathological aging, postural control evolves towards a more reactive mode for which the perturbation induced by the movement is not anticipated and leads to delayed and late postural adjustments.Methods: Elderly subjects performed rapid focal arm-raising movements towards a target, from an upright standing position in two stimuli conditions: simple reaction time and choice reaction time (CRT. Hand and center of pressure (CoP kinematics were compared between a control group and a frail group of the same age.Results: In frail individuals, the entire movement was impaired and slowed down. In addition, postural adjustments that classically precede and accompany the focal arm movement were delayed and reduced, especially in the CRT condition in which the motor prediction is more limited. Finally, a correlation between the time to CoP maximal velocity and the timed up-and-go score was observed.Conclusion: In these patients, it was concluded that the control of the CoP displacement evolved from a proactive mode in which the perturbation associated with the arm movement is anticipated toward a more reactive mode in which the perturbation is compensated by late and delayed adjustments.Keywords: frailty, anticipatory postural adjustments, backward disequilibrium

  2. The effects of trunk extensor and abdominal muscle fatigue on postural control and trunk proprioception in young, healthy individuals.

    Science.gov (United States)

    Larson, Dennis J; Brown, Stephen H M

    2018-02-01

    The purpose of this study was to induce both trunk extensor and abdominal muscle fatigue, on separate occasions, and compare their effects on standing postural control and trunk proprioception, as well as look at the effects of a recovery period on these outcome measures. A total of 20 individuals participated, with 10 (5 males and 5 females) completing either a standing postural control or lumbar axial repositioning protocol. Participants completed their randomly assigned protocol on two occasions, separated by at least 4  days, with either their trunk extensor or abdominal muscles being fatigued on either day. Postural control centre of pressure variables and trunk proprioception errors were compared pre- and post-fatigue. Results showed that both trunk extensor and abdominal muscle fatigue significantly degraded standing postural control immediately post-fatigue, with recovery occurring within 2 min post-fatigue. In general, these degradative effects on postural control appeared to be greater when the trunk extensor muscles were fatigued compared to the abdominal muscles. No statistically significant changes in trunk proprioception were found after either fatigue protocol. The present findings demonstrate our body's ability to quickly adapt and reweight somatosensory information to maintain postural control and trunk proprioception, as well as illustrate the importance of considering the abdominal muscles, along with the trunk extensor muscles, when considering the impact of fatigue on trunk movement and postural control. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Effect of IQoro® training on impaired postural control and oropharyngeal motor function in patients with dysphagia after stroke.

    Science.gov (United States)

    Hägg, Mary; Tibbling, Lita

    2016-07-01

    Conclusion All patients with dysphagia after stroke have impaired postural control. IQoro® screen (IQS) training gives a significant and lasting improvement of postural control running parallel with significant improvement of oropharyngeal motor dysfunction (OPMD). Objectives The present investigation aimed at studying the frequency of impaired postural control in patients with stroke-related dysphagia and if IQS training has any effect on impaired postural control in parallel with effect on OPMD. Method A prospective clinical study was carried out with 26 adult patients with stroke-related dysphagia. The training effect was compared between patients consecutively investigated at two different time periods, the first period with 15 patients included in the study more than half a year after stroke, the second period with 11 patients included within 1 month after stroke. Postural control tests and different oropharyngeal motor tests were performed before and after 3 months of oropharyngeal sensorimotor training with an IQS, and at a late follow-up (median 59 weeks after end of training). Result All patients had impaired postural control at baseline. Significant improvement in postural control and OPMD was observed after the completion of IQS training in both intervention groups. The improvements were still present at the late follow-up.

  4. Persons with multiple disabilities engage in stimulus choice and postural control with the support of a technology-aided program.

    Science.gov (United States)

    Lancioni, Giulio E; Singh, Nirbhay N; O'Reilly, Mark F; Sigafoos, Jeff; Perilli, Viviana; Campodonico, Francesca; Marchiani, Paola; Lang, Russell

    2015-05-01

    Technology-aided programs have been reported to help persons with disabilities develop adaptive responding and control problem behavior/posture. This study assessed one such program in which choice of stimulus events was used as adaptive responding for three adults with multiple disabilities. A computer system presented the participants stimulus samples. For each sample, they could perform a choice response (gaining access to the related stimulus whose length they could extend) or abstain from responding (making the system proceed to the next sample). Once choice responding had strengthened, the program also targeted the participants' problem posture (i.e., head and trunk forward bending). The stimulus exposure gained with a choice response was interrupted if the problem posture occurred. All three participants successfully (a) managed choice responses and access to preferred stimuli and (b) gained postural control (i.e., reducing the problem posture to very low levels). The practical implications of those results are discussed. © The Author(s) 2015.

  5. Three-dimensional kinematics of capuchin monkey bipedalism.

    Science.gov (United States)

    Demes, Brigitte

    2011-05-01

    Capuchin monkeys are known to use bipedalism when transporting food items and tools. The bipedal gait of two capuchin monkeys in the laboratory was studied with three-dimensional kinematics. Capuchins progress bipedally with a bent-hip, bent-knee gait. The knee collapses into flexion during stance and the hip drops in height. The knee is also highly flexed during swing to allow the foot which is plantarflexed to clear the ground. The forefoot makes first contact at touchdown. Stride frequency is high, and stride length and limb excursion low. Hind limb retraction is limited, presumably to reduce the pitch moment of the forward-leaning trunk. Unlike human bipedalism, the bipedal gait of capuchins is not a vaulting gait, and energy recovery from pendulum-like exchanges is unlikely. It extends into speeds at which humans and other animals run, but without a human-like gait transition. In this respect it resembles avian bipedal gaits. It remains to be tested whether energy is recovered through cyclic elastic storage and release as in bipedal birds at higher speeds. Capuchin bipedalism has many features in common with the facultative bipedalism of other primates which is further evidence for restrictions on a fully upright striding gait in primates that transition to bipedalism. It differs from the facultative bipedalism of other primates in the lack of an extended double-support phase and short aerial phases at higher speeds that make it a run by kinematic definition. This demonstrates that facultative bipedalism of quadrupedal primates need not necessarily be a walking gait. Copyright © 2011 Wiley-Liss, Inc.

  6. Global Postural Reeducation for patients with musculoskeletal conditions: a systematic review of randomized controlled trials

    OpenAIRE

    Ferreira, Giovanni E.; Barreto, Rodrigo G. P.; Robinson, Caroline C.; Plentz, Rodrigo D. M.; Silva, Marcelo F.

    2016-01-01

    ABSTRACT Objectives To systematically review randomized controlled trials that assessed the effects of Global Postural Reeducation (GPR) on patient-reported outcomes in conditions of the musculoskeletal system. Method An electronic search of MEDLINE (via PubMed), EMBASE, Cochrane CENTRAL, and SciELO was performed from their inception to June 2015. Randomized controlled trials that analyzed pain and patient-reported outcomes were included in this review. The Cochrane Collaboration’s Ri...

  7. [Effects of Surgically Treated Pelvic Ring and Acetabular Fractures on Postural Control].

    Science.gov (United States)

    Lang, P; Schnegelberger, A; Riesner, H-J; Stuby, F; Friemert, B; Palm, H-G

    2016-04-01

    The aim of surgical treatment of pelvic ring and acetabular fractures is to allow rapid mobilisation of patients in order to restore stance and gait stability (postural control), as this significantly correlates with a positive outcome. The regulation of postural stability is mainly controlled by transmission of proprioceptive stimuli. In addition, the pelvis serves as a connection between the legs and the spine and thus is also of great importance for mechanical stabilisation. It remains unclear whether surgical treatment of pelvic ring and acetabular fractures affects the regulation of postural control. Therefore, the aim of this study was to examine the impact of surgically treated pelvic ring and acetabular fractures on postural stability by means of computerised dynamic posturography (CDP) after a mean of 35 months and to compare the results with a healthy control group. A retrospective case control study of 38 patients with surgically treated pelvic ring and acetabular fractures and 38 healthy volunteers was carried out using CDP. The average time of follow-up was 35 (12-78) months. The most important outcome parameter in this investigation was the overall stability index (OSI). Hip joint mobility, the health-related quality of life (SF-12) and pain were supplementary outcome parameters. It was found that surgically treated pelvic ring and acetabular fractures had no influence on postural stability. The OSI was 2.1 ° in the patient group and 1.9 ° in the control group. There was no significant difference between the groups in hip joint mobility. A total of 52 % of patients showed no or only mild pain. Mean health-related quality of life was the same as in the total population. Surgically treated pelvic ring and acetabular fractures do not lead to deterioration in postural control in the mid term. This is of high prognostic importance for rapid mobilisation of the patients. Therefore no increase in the risk of falling is expected after successfully

  8. Biomechanics of running indicates endothermy in bipedal dinosaurs.

    Science.gov (United States)

    Pontzer, Herman; Allen, Vivian; Hutchinson, John R

    2009-11-11

    One of the great unresolved controversies in paleobiology is whether extinct dinosaurs were endothermic, ectothermic, or some combination thereof, and when endothermy first evolved in the lineage leading to birds. Although it is well established that high, sustained growth rates and, presumably, high activity levels are ancestral for dinosaurs and pterosaurs (clade Ornithodira), other independent lines of evidence for high metabolic rates, locomotor costs, or endothermy are needed. For example, some studies have suggested that, because large dinosaurs may have been homeothermic due to their size alone and could have had heat loss problems, ectothermy would be a more plausible metabolic strategy for such animals. Here we describe two new biomechanical approaches for reconstructing the metabolic rate of 14 extinct bipedal dinosauriforms during walking and running. These methods, well validated for extant animals, indicate that during walking and slow running the metabolic rate of at least the larger extinct dinosaurs exceeded the maximum aerobic capabilities of modern ectotherms, falling instead within the range of modern birds and mammals. Estimated metabolic rates for smaller dinosaurs are more ambiguous, but generally approach or exceed the ectotherm boundary. Our results support the hypothesis that endothermy was widespread in at least larger non-avian dinosaurs. It was plausibly ancestral for all dinosauriforms (perhaps Ornithodira), but this is perhaps more strongly indicated by high growth rates than by locomotor costs. The polarity of the evolution of endothermy indicates that rapid growth, insulation, erect postures, and perhaps aerobic power predated advanced "avian" lung structure and high locomotor costs.

  9. Early motor outpatient service intervention for postural control in preterm neonates Intervenção motora precoce ambulatorial para neonatos prematuros no controle postural

    Directory of Open Access Journals (Sweden)

    Clarissa Balbão Almeida

    2008-12-01

    Full Text Available Objective: To insure the motor acquisitions related to the Axial Spontaneous Not Communicative Development, which means postural control and displacement. This was done through an early motor intervention physiotherapy program in preterm neonates born at HSL-PUCRS. Materials and Methods: the interventional program included tasks of visual harassment, toys manipulation and postural control, based on Bobath concept. All five preterms who have participated in the program were evaluated by the physiotherapy service, using The Brazilian Scale of Child behavior Development in the First Year of Life, in the beginning of the study and repeated every two months. Results: The study shows no statistical significant results in relation to postural tasks, dynamic balance and displacement. However, a progression in the preterm’s classification evaluations was demonstrated. In the first month of evaluation the median was 3 (regular classification and in the third and fifth month of evaluation the median maintained in 4 (good classification. Conclusion: The early motor intervention provided a progression in the evaluation`s classification of motor acquisitions of the preterms development, however, no statistical significant results related to postural tasks, dinamic balance and displacemen was shown.Objetivo: Verificar as aquisições motoras relacionadas ao desenvolvimento axial espontâneo não comunicativo, ou seja, controle postural e deslocamento. Isto foi feito através de um programa de intervenção motora fisioterapêutica precoce em neonatos prematuros nascidos no Hospital São Lucas - PUCRS. Materiais e Métodos: Tarefas de perseguição visual, manipulação de brinquedos e de controle postural, baseados no conceito Bobath, foram implementadas no programa interventivo. Todos os 5 prematuros que participaram deste estudo foram avaliados pelo serviço de fisioterapia por meio da Escala de Desenvolvimento do Comportamento da Criança no Primeiro Ano

  10. [Voluntary postural control learning with a use of visual bio-feedback in patients with spinocerebellar degenerations].

    Science.gov (United States)

    Ustinova, K I; Ioffe, M E; Chernikova, L A; Kulikov, M A; Illarioshkin, S N; Markova, E D

    2004-01-01

    The study aimed at evaluation of possibility and features of voluntary postural control learning using biofeedback from a force platform in patients with spinocerebellar ataxias. Thirty-seven patients with different forms of spinocerebellar degenerations and 13 age-matched healthy subjects were trained to shift the center of pressure (CP) during several stabilographic computer games which tested an ability to learn 2 different types of voluntary postural control: general strategy and precise coordination of CP shifting. Despite the disturbances of static posture and ability for voluntary control of CP position, patients with spinocerebellar degenerations can learn to control a vertical posture using biofeedback on stabilogram. In contrast to healthy subjects, improvement of coordination in the training process does not exert a significant influence on the static posture characteristics, in particular on lateral CP oscillations. The results obtained suggest involvement of the cerebellum in both types of postural control that distinguishes them from pathology caused by motor cortex and nigro-striatal system involved only in one type of postural control.

  11. Motion Planning for Bipedal Robot to Perform Jump Maneuver

    Directory of Open Access Journals (Sweden)

    Xinyang Jiang

    2018-01-01

    Full Text Available The remarkable ability of humans to perform jump maneuvers greatly contributes to the improvements of the obstacle negotiation ability of humans. The paper proposes a jumping control scheme for a bipedal robot to perform a high jump. The half-body of the robot is modeled as three planar links and the motion during the launching phase is taken into account. A geometrically simple motion was first conducted through which the gear reduction ratio that matches the maximum motor output for high jumping was selected. Then, the following strategies to further exploit the motor output performance was examined: (1 to set the maximum torque of each joint as the baseline that is explicitly modeled as a piecewise linear function dependent on the joint angular velocity; (2 to exert it with a correction of the joint angular accelerations in order to satisfy some balancing criteria during the motion. The criteria include the location of ZMP (zero moment point and the torque limit. Using the technique described above, the jumping pattern is pre-calculated to maximize the jump height. Finally, the effectiveness of the proposed method is evaluated through simulations. In the simulation, the bipedal robot model achieved a 0.477-m high jump.

  12. A preliminary study of static and dynamic balance in sedentary obese young adults: the relationship between BMI, posture and postural balance.

    Science.gov (United States)

    do Nascimento, J A; Silva, C C; Dos Santos, H H; de Almeida Ferreira, J J; de Andrade, P R

    2017-12-01

    The aim of this study was to evaluate the postural control of obese young adults with normal body mass index during different static (bipedic and unipedic support) and dynamic postural conditions (gait velocity and limits of stability) in order to compare the static and dynamic balance of these individuals. A cross-sectional quantitative study was carried out to evaluate static and dynamic balance in 25 sedentary individuals. The sample was divided into two groups, 10 in the normal-weight group (24.70 ± 3.89 years and 21.5 ± 1.66 kg m -2 ) and 15 in the obese group (26.80 ± 5.16 years and 35.66 ± 4.29 kg m -2 ). Postural evaluation was performed through visual inspection, and balance analyses were performed using the Timed Up & Go test (TUGT) and Balance System (Biodex). Descriptive analyses, Fisher's exact test and Mann Whitney U-tests were performed using the Statistical Package for Social Sciences (SPSS - 20.0, Armonk, NY) software. Most of the obese volunteers presented postural alterations, such as head protrusion (47.6%), hyperkyphosis (46.7%) and hyperlordosis (26.7%). Medial-lateral dynamic displacement, risk of falls and mean time to perform the limits of stability test and TUGT were higher for obese subjects (P  0.05) for static balance tests for either bipedal or unipedal tasks. The disadvantage presented by the young obese subjects occurs in dynamic activities, representing worse balance and an increase in time needed to accomplish these activities. © 2017 World Obesity Federation.

  13. ATLETAS DE TAEKWONDO TÊM MELHOR CONTROLE POSTURAL DO QUE ATLETAS DE HANDEBOL E FUTEBOL AMERICANO

    OpenAIRE

    Shirabe, Nelson Akio; Silva, Rubens Alexandre da; Oliveira, Márcio Rogério; Nowotny, Alexandre Henrique; Sturion, Leandro Amaral; Gil, André Wilson de Oliveira; Andraus, Rodrigo Antonio Carvalho; Carvalho, Adriana Paula Fontana

    2017-01-01

    RESUMO Introdução: O controle postural é um pré-requisito importante para o desempenho do atleta no esporte. Além disso, o sistema de controle postural contribui para a prevenção de lesões. Déficits nesse sistema podem levar a instabilidade corporal e sobrecarga das estruturas musculoesqueléticas, gerando disfunção e dor. Objetivos: A proposta deste estudo foi avaliar o controle postural em três diferentes modalidades esportivas: taekwondo, handebol e futebol americano. Métodos: Todos os atle...

  14. Study of the human postural control system during quiet standing using detrended fluctuation analysis

    Science.gov (United States)

    Teresa Blázquez, M.; Anguiano, Marta; de Saavedra, Fernando Arias; Lallena, Antonio M.; Carpena, Pedro

    2009-05-01

    The detrended fluctuation analysis is used to study the behavior of different time series obtained from the trajectory of the center of pressure, the output of the activity of the human postural control system. The results suggest that these trajectories present two different regimes in their scaling properties: persistent (for high frequencies, short-range time scale) to antipersistent (for low frequencies, long-range time scale) behaviors. The similitude between the results obtained for the measurements, done with both eyes open and eyes closed, indicate either that the visual system may be disregarded by the postural control system while maintaining the quiet standing, or that the control mechanisms associated with each type of information (visual, vestibular and somatosensory) cannot be disentangled with the type of analysis performed here.

  15. The Effects of Slackline Balance Training on Postural Control in Older Adults.

    Science.gov (United States)

    Thomas, Monika; Kalicinski, Michael

    2016-07-01

    The present study investigated whether slackline training enhances postural control in older adults. Twenty-four participants were randomized into an intervention and a control group. The intervention group received 6 weeks of slackline training, two times per week. Pre-post measurement included the time of different standing positions on a balance platform with and without an external disturbance and the acceleration of the balance platform. Results showed significantly improved standing times during one-leg stance without external disturbance and a significantly reduced acceleration of the balance platform for the intervention group after the training period during tandem stance with and without an external disturbance. We conclude that slackline training in older adults has a positive impact on postural control and thus on the reduction of fall risk.

  16. Modeling Cerebral Blood Flow Control During Posture Change from Sitting to Standing

    DEFF Research Database (Denmark)

    Olufsen, Mette; Tran, Hien; Ottesen, Johnny T.

    2004-01-01

    , the heart, and venous valves. We use physiologically based control mechanisms to describe the regulation of cerebral blood velocity and arterial pressure in response to orthostatic hypotension resulting from postural change. Beyond active control mechanisms we also have to include certain passive non-linearities......Hypertension, decreased cerebral blood flow, and diminished cerebral blood flow regulation, are among the first signs indicating the presence of cerebral vascular disease. In this paper, we will present a mathematical model that can predict blood flow and pressure during posture change from sitting...... in some of the compliance-pressure and resistance-pressure relationships. Futhermore, an acurate and physiologically based submodel, describing the dynamics of how gravity effects the blood distribution during suspine changes, is included. To justify the fidelity of our mathematical model and control...

  17. A Trunk Support System to Identify Posture Control Mechanisms in Populations Lacking Independent Sitting.

    Science.gov (United States)

    Goodworth, Adam D; Wu, Yen-Hsun; Felmlee, Duffy; Dunklebarger, Ellis; Saavedra, Sandra

    2017-01-01

    Populations with moderate-to-severe motor control impairments often exhibit degraded trunk control and/or lack the ability to sit unassisted. These populations need more research, yet their underdeveloped trunk control complicates identification of neural mechanisms behind their movements. The purpose of this study was to overcome this barrier by developing the first multi-articulated trunk support system to identify visual, vestibular, and proprioception contributions to posture in populations lacking independent sitting. The system provided external stability at a user-specific level on the trunk, so that body segments above the level of support required active posture control. The system included a tilting surface (controlled via servomotor) as a stimulus to investigate sensory contributions to postural responses. Frequency response and coherence functions between the surface tilt and trunk support were used to characterize system dynamics and indicated that surface tilts were accurately transmitted up to 5 Hz. Feasibility of collecting kinematic data in participants lacking independent sitting was demonstrated in two populations: two typically developing infants, [Formula: see text] months, in a longitudinal study (eight sessions each) and four children with moderate-to-severe cerebral palsy (GMFCS III-V). Adaptability in the system was assessed by testing 16 adults (ages 18-63). Kinematic responses to continuous pseudorandom surface tilts were evaluated across 0.046-2 Hz and qualitative feedback indicated that the trunk support and stimulus were comfortable for all subjects. Concepts underlying the system enable both research for, and rehabilitation in, populations lacking independent sitting.

  18. Delayed Compensatory Postural Adjustments After Lateral Perturbations Contribute to the Reduced Ability of Older Adults to Control Body Balance.

    Science.gov (United States)

    Claudino, Renato; Dos Santos, Marcio José; Mazo, Giovana Zarpellon

    2017-10-01

    The goal of this study was to investigate the timing of compensatory postural adjustments in older adults during body perturbations in the mediolateral direction, circumstances that increase their risk of falls. The latencies of leg and trunk muscle activation to body perturbations at the shoulder level and variables of center of pressure excursion, which characterize postural stability, were analyzed in 40 older adults (nonfallers and fallers evenly split) and in 20 young participants. The older adults exhibited longer latencies of muscular activation in eight out of 15 postural muscles as compared with young participants; for three muscles, the latencies were longer for the older fallers than nonfallers. Simultaneously, the time for the center of pressure displacement reached its peak after the perturbation was significant longer in both groups of older adults. The observed delays in compensatory postural adjustments may affect the older adults' ability to prompt control body balance after postural disturbances and predispose them to falls.

  19. Overshoot intrusion forces promote robophysical bipedal walking on homogenous granular media

    Science.gov (United States)

    Xiong, Xiaobin; Aguilar, Jeffrey; Rieser, Jennifer; Kim, Allison; Ames, Aaron; Goldman, Daniel

    Bipedal walking on natural terrain such as sand and loose rubble is challenging because deformable terrains complicate foot-terrain interaction (modelled as rigid contact on hard ground). To discover how deformable ground interaction influences bipedal walking, we study constant center-of-mass height dynamic walking of a flat-footed bipedal robophysical device (40cm tall, 3 motors per leg) on homogeneous granular terrain of loosely packed poppy seeds. The planarized robot is controlled such that its zero-moment point (ZMP) stays within a stability region (termed support polygon for hard ground walking). Granular resistive force theory [Li et al, Science 2013] fails to predict this stability region despite success in predicting performance of multi-legged robots on granular media. We posit that the stability region formulation requires understanding of static reaction forces; we estimate these effects by measuring forces on a flat plate (3cmx3cm) vertically plunged (at 1 cm/second) into loosely packed poppy seeds with controlled pauses during the intrusion. Following a pause ( 3 second), the force overshoots 13%-38% to that of continuous intrusion at depths from 45mm-5mm. The overshoot forces rationalize the stability regions and enable robust bipedal walking.

  20. Effectiveness of Neuro-Developmental Treatment (Bobath Concept) on postural control and balance in Cerebral Palsied children.

    Science.gov (United States)

    Tekin, Fatih; Kavlak, Erdogan; Cavlak, Ugur; Altug, Filiz

    2018-01-01

    The aim of this study was to show the effects of an 8-week Neurodevelopmental Treatment based posture and balance training on postural control and balance in diparetic and hemiparetic Cerebral Palsied children (CPC). Fifteen CPC (aged 5-15 yrs) were recruited from Denizli Yağmur Çocukları Rehabilitation Centre. Gross Motor Function Classification System, Gross Motor Function Measure, 1-Min Walking Test, Modified Timed Up and Go Test, Paediatric Balance Scale, Functional Independence Measure for Children and Seated Postural Control Measure were used for assessment before and after treatment. An 8-week NDT based posture and balance training was applied to the CPC in one session (60-min) 2 days in a week. After the treatment program, all participants showed statistically significant improvements in terms of gross motor function (p< 0.05). They also showed statistically significant improvements about balance abilities and independence in terms of daily living activities (p< 0.05). Seated Postural Control Measure scores increased after the treatment program (p< 0.05). The results of this study indicate that an 8-week Neurodevelopmental Treatment based posture and balance training is an effective approach in order to improve functional motor level and functional independency by improving postural control and balance in diparetic and hemiparetic CPC.

  1. How plantar exteroceptive efficiency modulates postural and oculomotor control: inter-individual variability

    Directory of Open Access Journals (Sweden)

    Arnaud eFoisy

    2016-05-01

    Full Text Available In a previous experiment, we showed that among young and healthy subjects, thin plantar inserts improve postural control and modify vergence amplitudes. In this experiment, however, significant inter-individual variability was observed. We hypothesize that its origin could be attributed to a different reliance upon feet cutaneous afferents. In order to test this hypothesis, we re-analyzed the data relative to 31 young (age 25,7±3,8 and healthy subjects who participated in the first experiment after having classified them into two groups depending on their Plantar Quotient (PQ = Surface area of CoP foam / Surface area of CoP firm ground x100. Foam decreases the information arising from the feet, normally resulting in a PQ>100. Hence, the PQ provides information on the weight of plantar cutaneous afferents used in postural control. Twelve people were Plantar-Independent Subjects, as indicated by a PQ<100. These individuals did not behave like the Normal Plantar Quotient Subjects: they were almost insensitive to the plantar stimulations in terms of postural control and totally insensitive in terms of oculomotor control. We conclude that the inter-individual variability observed in our first experiment is explained by the subjects’ degree of plantar reliance. We propose that plantar independence is a dysfunctional situation revealing an inefficiency in plantar cutaneous afferents. The latter could be due to a latent somatosensory dysfunction generating a noise which prevents the CNS from correctly processing and using feet somatosensory afferents both for balance and vergence control: Plantar Irritating Stimulus. Considering the non-noxious nature and prevalence of this phenomenon, these results can be of great interest to researchers and clinicians who attempt to trigger postural or oculomotor responses through mechanical stimulation of the foot sole.

  2. A Telerehabilitation Program Improves Postural Control in Multiple Sclerosis Patients: A Spanish Preliminary Study

    Directory of Open Access Journals (Sweden)

    Rosa Ortiz-Gutiérrez

    2013-10-01

    Full Text Available Postural control disorders are among the most frequent motor disorder symptoms associated with multiple sclerosis. This study aims to demonstrate the potential improvements in postural control among patients with multiple sclerosis who complete a telerehabilitation program that represents a feasible alternative to physical therapy for situations in which conventional treatment is not available. Fifty patients were recruited. Control group (n = 25 received physiotherapy treatment twice a week (40 min per session. Experimental group (n = 25 received monitored telerehabilitation treatment via videoconference using the Xbox 360® and Kinect console. Experimental group attended 40 sessions, four sessions per week (20 min per session.The treatment schedule lasted 10 weeks for both groups. A computerized dynamic posturography (Sensory Organization Test was used to evaluate all patients at baseline and at the end of the treatment protocol. Results showed an improvement over general balance in both groups. Visual preference and the contribution of vestibular information yielded significant differences in the experimental group. Our results demonstrated that a telerehabilitation program based on a virtual reality system allows one to optimize the sensory information processing and integration systems necessary to maintain the balance and postural control of people with multiple sclerosis. We suggest that our virtual reality program enables anticipatory PC and response mechanisms and might serve as a successful therapeutic alternative in situations in which conventional therapy is not readily available.

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

    Directory of Open Access Journals (Sweden)

    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.

  4. Adiposity and postural balance control: Correlations between bioelectrical impedance and stabilometric signals in elderly Brazilian women

    Science.gov (United States)

    Mainenti, Míriam Raquel Meira; de Carvalho Rodrigues, Érika; de Oliveira, Juliana Flávia; de Sá Ferreira, Arthur; Dias, Cristina Márcia; dos Santos Silva, André Luís

    2011-01-01

    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. PMID:22179151

  5. Effects of kettlebell training on postural coordination and jump performance: a randomized controlled trial.

    Science.gov (United States)

    Jay, Kenneth; Jakobsen, Markus D; Sundstrup, Emil; Skotte, Jørgen H; Jørgensen, Marie B; Andersen, Christoffer H; Pedersen, Mogens T; Andersen, Lars L

    2013-05-01

    The aim of this study was to investigate the effectiveness of a worksite intervention using kettlebell training to improve postural reactions to perturbation and jump performance. This single-blind randomized controlled trial involved 40 adults (n = 40) from occupations with a high prevalence of musculoskeletal pain and discomfort (mean age 44 years, body mass index 23 kg·m, 85% women). A blinded examiner took measures at baseline and follow-up. Participants were randomly assigned to a training group-doing kettlebell swings 3 times a week for 8 weeks-or to a control group. The outcome measures were postural reactions to sudden perturbation and maximal countermovement jump height. Compared with the control group, the training group had a significant decreased stopping time after perturbation (-109 ms, 95% confidence interval [-196 to -21]). Jump height increased significantly in the training group (1.5 cm, 95% confidence interval [0.5 to 2.5]), but this was nonsignificantly different from control. Kettlebell training improves postural reactions to sudden perturbation. Future studies should investigate whether kettlebell training can reduce the risk of low back injury in occupations with manual material handling or patient handling where sudden perturbations often occur.

  6. Modeling Cerebral Blood Flow Control During Posture Change from Sitting to Standing

    DEFF Research Database (Denmark)

    Olufsen, Mette; Tran, Hien; Ottesen, Johnny T.

    2004-01-01

    Hypertension, decreased cerebral blood flow, and diminished cerebral blood flow regulation, are among the first signs indicating the presence of cerebral vascular disease. In this paper, we will present a mathematical model that can predict blood flow and pressure during posture change from sitting...... to standing. The mathematical model uses a compartmental approach to describe pulsatile blood flow and pressure in a number of compartments representing the systemic circulation. Our model includes compartments representing the trunk and upper extremities, the lower extremities, the brain, the atria......, the heart, and venous valves. We use physiologically based control mechanisms to describe the regulation of cerebral blood velocity and arterial pressure in response to orthostatic hypotension resulting from postural change. Beyond active control mechanisms we also have to include certain passive non...

  7. The effects of vestibular stimulation and fatigue on postural control in classical ballet dancers.

    Science.gov (United States)

    Hopper, Diana M; Grisbrook, Tiffany L; Newnham, Prudence J; Edwards, Dylan J

    2014-01-01

    This study aimed to investigate the effects of ballet-specific vestibular stimulation and fatigue on static postural control in ballet dancers and to establish whether these effects differ across varying levels of ballet training. Dancers were divided into three groups: professional, pre-professional, and recreational. Static postural control of 23 dancers was measured on a force platform at baseline and then immediately, 30 seconds, and 60 seconds after vestibular stimulation (pirouettes) and induction of fatigue (repetitive jumps). The professional dancers' balance was unaffected by both the vestibular stimulation and the fatigue task. The pre-professional and recreational dancers' static sway increased following both perturbations. It is concluded that professional dancers are able to compensate for vestibular and fatiguing perturbations due to a higher level of skill-specific motor training.

  8. Optimal arm posture control and tendon traction forces of a coupled tendon-driven manipulator

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Shugen [Ibaraki Univ., Hitachi (Japan). Faculty of Engineering

    1997-05-01

    In this study, the optimum arm posture of a coupled tendon-driven multijoint manipulator arm (or CT Arm) at maximum payload output was derived and the corresponding tendon traction forces were also analyzed, during management of a heavy payload by the manipulator in a gravity environment. The CT Arm is special tendon traction transmission mechanism in which a pair of tendons used to drive a joint is pulled from base actuators via pulleys mounted on the base-side joints. This mechanism enables optimal utilization of the coupled drive function of tendon traction forces and thus enables the lightweight manipulator to exhibit large payload capability. The properties of the CT Arm mechanism are elucidated by the proposed optimal posture control scheme. Computer simulation was also executed to verify the validity of the proposed control scheme. (author)

  9. Effect of Feldenkrais exercises on dual task postural control in older adults

    Directory of Open Access Journals (Sweden)

    Ullmann G

    2014-07-01

    Full Text Available Gerhild Ullmann,1 Harriet G Williams2 1Social and Behavioral Sciences, University of Memphis, School of Public Health, Memphis, TN, USA; 2Exercise Science, University of South Carolina, Columbia, SC, USAAgmon et al1 recently published an interesting systematic review of interventions to improve dual-task postural control in older adults. Given that many everyday activities (eg, walking and carrying groceries require dual-task postural control, this is an important topic. This type of research is integral to expanding scientific knowledge in the field of interventions. The authors describe the methods of the review process clearly. However, in our opinion, adherence to the stated methods is not always evident. Read the original paper

  10. Influência da dor no controle postural de mulheres com dor cervical

    Directory of Open Access Journals (Sweden)

    Juliana Soares

    2013-03-01

    Full Text Available DOI: http://dx.doi.org/10.5007/1980-0037.2013v15n3p371 O objetivo foi verificar a influência da dor no controle postural de mulheres com dor cervicale a relação com as possíveis alterações nos sistemas sensoriais e postura corporal.O grupo dor cervical foi composto por mulheres, entre 20 e 50 anos, com dor cervicalpor mais de três meses e o grupo controle por 20 mulheres sem dor cervical. Para caracterização, utilizaram-se anamnese, índice de incapacidade cervical e Escala Visual Analógica. O equilíbrio postural foi avaliado por uma plataformade força. O equilíbrio com manipulação dos sistemas sensoriais foi avaliado pela posturografia dinâmica Foam-laser, expondo o indivíduo a seis testes de organização sensorial. A postura foi avaliada pelo Software de Avaliação Postural. Normalidade das variáveis verificada pelo teste de Shapiro Wilk etestes t de Student e Mann Whitney para comparação entre grupos, nível de significânciade 5%. Os grupos apresentaram homogeneidade nas variáveis demográficas. No equilíbrio postural, observou-se maior amplitude e velocidade de deslocamento do centro de pressão no grupo dor cervical, demonstrando maior oscilação postural. Houve diferença significativa no ângulo crâniovertebral, mostrando anteriorização da cabeça nas mulheres sintomáticas. Na posturografia dinâmica,observou-se diferença entre os grupos sendo que o escore obtido nas seiscondições sensoriais demonstrou que o grupo dor cervical apresentou maior comprometimento do equilíbrio. Dor cervical e postura anteriorizada da cabeçatêm efeito deletério no controle postural de mulheres sintomáticas, tanto na postura estática quanto na postura dinâmica.

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

    Directory of Open Access Journals (Sweden)

    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.

  12. Elderly Use Proprioception Rather than Visual and Vestibular Cues for Postural Motor Control.

    Science.gov (United States)

    Wiesmeier, Isabella Katharina; Dalin, Daniela; Maurer, Christoph

    2015-01-01

    Multiple factors have been proposed to contribute to the deficits of postural control in the elderly. They were summarized as sensory, motor, and higher-level adaptation deficits. Using a model-based approach, we aimed to identify which of these deficits mainly determine age-related changes in postural control. We analyzed postural control of 20 healthy elderly people with a mean age of 74 years. The findings were compared to data from 19 healthy young volunteers (mean age 28 years) and 16 healthy middle-aged volunteers (mean age 48 years). Postural control was characterized by spontaneous sway measures and measures of perturbed stance. Perturbations were induced by pseudorandom anterior-posterior tilts of the body support surface. We found that spontaneous sway amplitude and velocity were significantly larger, and sway frequencies were higher in elderly compared to young people. Body excursions as a function of tilt stimuli were clearly different in elderly compared to young people. Based on simple feedback model simulations, we found that elderly favor proprioceptive over visual and vestibular cues, other than younger subjects do. Moreover, we identified an increase in overall time delay challenging the feedback systems stability, and a decline in the amplitude of the motor feedback, probably representing weakness of the motor system. In general, these parameter differences between young and old may result from both deficits and compensation strategies in the elderly. Our model-based findings correlate well with deficits measured with clinical balance scores, which are widely used in clinical practice.

  13. Perceptual Inhibition is Associated with Sensory Integration in Standing Postural Control Among Older Adults

    OpenAIRE

    Redfern, Mark S.; Jennings, J. Richard; Mendelson, David; Nebes, Robert D.

    2009-01-01

    In older adults, maintaining balance and processing information typically interfere with each other, suggesting that executive functions may be engaged for both. We investigated associations between measures of inhibitory processes and standing postural control in healthy young and older adults. Perceptual and motor inhibition was measured using a protocol adapted from Nassauer and Halperin (2003, Dissociation of perceptual and motor inhibition processes through the use of novel computerized ...

  14. Falls and Postural Control in Older Adults With Eye Refractive Errors

    Directory of Open Access Journals (Sweden)

    Afsun Nodehi-Moghadam

    2016-04-01

    Conclusion: Vision impairment of older adults due to refractive error is not associated with an increase in falls. Furthermore, TUG test results did not show balance disorders in these groups. Further research, such as assessment of postural control with advanced devices and considering other falling risk factors is also needed to identify the predictors of falls in older adults with eye refractive errors.

  15. Relationship between postural control and fine motor skills in preterm infants at 6 and 12 months adjusted age.

    Science.gov (United States)

    Wang, Tien-Ni; Howe, Tsu-Hsin; Hinojosa, Jim; Weinberg, Sharon L

    2011-01-01

    We examined the relationship between postural control and fine motor skills of preterm infants at 6 and 12 mo adjusted age. The Alberta Infant Motor Scale was used to measure postural control, and the Peabody Developmental Motor Scales II was used to measure fine motor skills. The data analyzed were taken from 105 medical records from a preterm infant follow-up clinic at an urban academic medical center in south Taiwan. Using multiple regression analyses, we found that the development of postural control is related to the development of fine motor skills, especially in the group of preterm infants with delayed postural control. This finding supports the theoretical assumption of proximal-distal development used by many occupational therapists to guide intervention. Further research is suggested to corroborate findings.

  16. Effect of ankle-foot orthosis on postural control after stroke: a systematic review.

    Science.gov (United States)

    Guerra Padilla, M; Molina Rueda, F; Alguacil Diego, I M

    2014-09-01

    Stroke is currently the main cause of permanent disability in adults. The impairments are a combination of sensory, motor, cognitive and emotional changes that result in restrictions on the ability to perform basic activities of daily living (BADL). Postural control is affected and causes problems with static and dynamic balance, thus increasing the risk of falls and secondary injuries. The purpose of this review was to compile the literature to date, and assess the impact of ankle-foot orthosis (AFO) on postural control and gait in individuals who have suffered a stroke. The review included randomised and controlled trials that examined the effects of AFO in stroke patients between 18 and 80 years old, with acute or chronic evolution. No search limits on the date of the studies were included, and the search lasted until April 2011. The following databases were used: Pubmed, Trip Database, Cochrane library, Embase, ISI Web Knowledge, CINHAL and PEDro. Intervention succeeded in improving some gait parameters, such as speed and cadence. However it is not clear if there was improvement in the symmetry, postural sway or balance. Because of the limitations of this systematic review, due to the clinical diversity of the studies and the methodological limitations, 0these results should be considered with caution. Copyright © 2011 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.

  17. Study on an advanced early rehabilitation training system for postural control using a tilting bed

    Science.gov (United States)

    Yu, Chang-Ho; Kim, Kyong; Kwon, Tae-Kyu; Hong, Chul-Un; Kim, Nam-Gyun

    2005-12-01

    It proposed a new early rehabilitation training system for postural control using a tilting bed, a visual display and a force plate. The conventional rehabilitation systems for postural control can't be applied to the patients lying in bed because the rehabilitation training using those systems is only possible when the patient can stand up by himself or herself. Moreover, there did not exist any device that could provide the sense of balance or the sensation of walking to the patients in bed. The software for the system consists of the training program and the analysis program. The training program was designed to improve the ability of postural control of the subjects by repeated training of moving the center of pressure (COP) applied to the forceplate. The training program consists of the COP maintaining training and the COP movement training in horizontal, vertical, 45° and -45° directions. The analysis program consists of the COP moving time analysis modules, the COP maintaining time analysis module. Through the experiments with real people, it verified the effectiveness of the new early rehabilitation training system. The results showe that this system is an effective system for early rehabilitation training and that our system might be useful as clinical equipment.

  18. How does practise of internal Chinese martial arts influence postural reaction control?

    Science.gov (United States)

    Gorgy, Olivier; Vercher, Jean-Louis; Coyle, Thelma

    2008-04-01

    The aim of this study was to determine the effects of Chinese martial arts practice on postural reaction control after perturbation. Participants standing in Romberg tandem posture were subjected to an unexpected lateral platform translation with the eyes open or closed at two translation amplitudes. The peak displacement of the centre of pressure and of the centre of mass, and the onset latency of muscular activity (tibialis anterior, gastrocnemius, lumbodorsal muscular group, and rectus abdominis), were evaluated for martial arts practitioners and for sport and non-sport participants. Compared with the sport and non-sport participants, the martial arts group showed lower maximal centre of pressure and centre of mass peak displacements in both the lateral and anterior - posterior directions, but no difference was found in the onset of muscular responses. We conclude that martial arts practice influences postural reaction control during a fixed-support strategy in a tandem task. The martial arts group used the ankle joint more frequently than the sport and non-sport participants, especially in the eyes-closed conditions. Our results suggest that the better balance recovery in the martial arts group is a consequence of better control of biomechanical properties of the lower limbs (e.g. through muscular response by co-contraction), not a change in the neuromuscular temporal pattern.

  19. Efficacy and Effectiveness of Physical Therapy in Enhancing Postural Control in Children With Cerebral Palsy

    Directory of Open Access Journals (Sweden)

    Susan R. Harris

    2005-01-01

    Full Text Available The purpose of this article was to conduct a systematic review of studies that examined the efficacy and effectiveness of postural control intervention strategies for children with CP. Only physical therapy interventions were included, e.g. adaptive seating devices, ankle foot orthoses, neurodevelopmental treatment. A multifaceted search strategy was employed to identify all potential studies published between 1990 and 2004. The search strategy included electronic databases, reference list scanning, author and citation tracking of relevant studies, and hand searching of pediatric physical therapy journals and conference proceedings. Twelve studies (1991–2004, comprising ten group design studies and two single subject studies, met our inclusion criteria. A variety of age ranges and severity of children with cerebral palsy (n = 132 participated in the studies. The study quality scores ranged from 2 to 7 (total possible range of 0 to 7 with a median score of 5.5 and a mode of 6. As was true in an earlier systematic review on adaptive seating, most of the 12 ‘experimental’ studies published since 1990 that were aimed at evaluating the effectiveness of postural control strategies provided lower levels of evidence, i.e. Sackett Levels III to V. Additional studies with stronger designs are needed to establish that postural control interventions for children with CP are effective.

  20. Effects of Genu Recurvatum on Postural Control: A Preliminary Study

    National Research Council Canada - National Science Library

    Swinson, Thomas

    1998-01-01

    .... Eleven subjects with bilateral genu recurvatum were matched with 11 controls. Force plate data were acquired while subjects were tested for steadiness during one leg standing balance and the balance leg reach test...

  1. Kinematická analýza posturálních změn v bipedálním stoji při aplikaci podnětu ze zevního prostředí a modifikaci vizuální scény u pacientů po plastice předního zkříženého vazu Kinematic analysis of postural changes in bipedal stance at application of stimulus from external environment and modifi cation of visual scene in patients with anterior cruciate ligament reconstruction

    Directory of Open Access Journals (Sweden)

    Miroslav Janura

    2007-01-01

    Full Text Available Tato studie se zabývá změnami postury při modifikované zrakové scéně a při aplikaci podnětu ze zevního prostředí u zdravých jedinců a u pacientů po plastice předního zkříženého vazu (LCA za nezměněné a modifi kované vizuální scény. Do vyšetřovaného souboru bylo zahrnuto 11 pacientů po plastice LCA a 14 zdravých jedinců. Modifi kace vizuální scény bylo dosaženo prostřednictvím speciálního optického systému Olympus – Eye trek FMD-700. Zevní podnět byl realizován pomocí nárazu letícího míče. K hodnocení posturálních změn jsme využili kinematickou analýzu. U pacientů po rekonstrukci LCA i u zdravých jedinců jsme nejvíce diferencí v jednotlivých způsobech provedení nalezli pro kinematické parametry na dolních končetinách a trupu. U obou skupin probandů jsme zaznamenali podobné tendence k posturálním změnám. Při porovnávání kinematických parametrů mezi skupinou pacientů a zdravých jedinců jsme nalezli rozdíly v poloze horních končetin. Pro dolní končetiny a trup (s výjimkou minimální velikosti úhlu bérec – stehno při modifi kované scéně s reálným podnětem nejsou rozdíly mezi oběma skupinami statisticky významné. Tears and rupture of the anterior cruciate ligament (ACL, which has an important function in knee joint stability, are very common and more so in sports. ACL injury can be managed in two ways. One alternative pertains to conservative therapy whereas the second variant is surgical intervention (reconstruction. The number of ACL reconstructions has risen recently. The purpose of this study was to analyze the postural changes in bipedal stance at application of a stimulus from external environment and the resultant modifi cation in the visual scene in patients with ACL reconstruction. The examined group consisted of 25 subjects – 11 patients with ACL reconstruction and 14 healthy adults. The external stimulus was realized by striking

  2. Stochastic resonance whole-body vibration improves postural control in health care professionals: a worksite randomized controlled trial.

    Science.gov (United States)

    Elfering, Achim; Schade, Volker; Stoecklin, Lukas; Baur, Simone; Burger, Christian; Radlinger, Lorenz

    2014-05-01

    Slip, trip, and fall injuries are frequent among health care workers. Stochastic resonance whole-body vibration training was tested to improve postural control. Participants included 124 employees of a Swiss university hospital. The randomized controlled trial included an experimental group given 8 weeks of training and a control group with no intervention. In both groups, postural control was assessed as mediolateral sway on a force plate before and after the 8-week trial. Mediolateral sway was significantly decreased by stochastic resonance whole-body vibration training in the experimental group but not in the control group that received no training (p resonance whole-body vibration training is an option in the primary prevention of balance-related injury at work. Copyright 2014, SLACK Incorporated.

  3. Comparison of posture and muscle control pattern between male and female computer users with musculoskeletal symptoms.

    Science.gov (United States)

    Yang, Jeng-Feng; Cho, Chiung-Yu

    2012-07-01

    The primary purpose of this study was to compare the posture and muscle control patterns between male and female computer users with musculoskeletal symptoms. Forty computer users were recruited. Each subject performed a preferred speed typing, a fast speed typing, and a repetitive mouse task. The independent variables were gender, typing speed, and time. There were significant differences between genders for head and neck flexion angles when they were performing the preferred speed typing task. Significant differences between genders were also found for upper extremity angles when they were performing the repetitive mouse task. Male computer users had a smaller root mean square of the right extensor digitorium than females. In general, postural differences were significant between genders, even when the subjects' table and chair were adjusted to meet their anthropometry. Our results suggest that modifications of the computer working environment may be different between genders. Copyright © 2011 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  4. Perceptual inhibition is associated with sensory integration in standing postural control among older adults.

    Science.gov (United States)

    Redfern, Mark S; Jennings, J Richard; Mendelson, David; Nebes, Robert D

    2009-09-01

    In older adults, maintaining balance and processing information typically interfere with each other, suggesting that executive functions may be engaged for both. We investigated associations between measures of inhibitory processes and standing postural control in healthy young and older adults. Perceptual and motor inhibition was measured using a protocol adapted from Nassauer and Halperin (2003, Dissociation of perceptual and motor inhibition processes through the use of novel computerized conflict tasks. Journal of the International Neuropsychological Society, 9, 25-30). These measures were then correlated to postural sway during standing conditions that required resolving various levels of sensory conflict, for example, world-fixed versus sway-referenced floor and visual scene. In the older adults, perceptual inhibition was positively correlated with sway amplitude on a sway-referenced floor and with a fixed visual scene (r = .68, p sensory integration process important for maintaining balance in older adults.

  5. The postural control can be optimized by the first movement initiation condition encountered when submitted to muscle fatigue.

    Science.gov (United States)

    Monjo, Florian; Forestier, Nicolas

    2017-08-01

    We investigated whether and how the movement initiation condition (IC) encountered during the early movements performed following focal muscle fatigue affects the postural control of discrete ballistic movements. For this purpose, subjects performed shoulder flexions in a standing posture at maximal velocity under two movement IC, i.e., in self-paced conditions and submitted to a Stroop-like task in which participants had to trigger fast shoulder flexions at the presentation of incongruent colors. Shoulder flexion kinematics, surface muscle activity of focal and postural muscles as well as center-of-pressure kinematics were recorded. The initial IC and the order in which subjects were submitted to these two conditions were varied within two separate experimental sessions. IC schedule was repeated before and after fatigue protocols involving shoulder flexors. The aim of this fatigue procedure was to affect acceleration-generating capacities of focal muscles. In such conditions, the postural muscle activity preceding and accompanying movement execution is expected to decrease. Following fatigue, when subjects initially moved in self-paced conditions, postural muscle activity decreased and scaled to the lower focal peak acceleration. This postural strategy then transferred to the Stroop-like task. In contrast, when subjects initially moved submitted to the Stroop-like task, postural muscle activity did not decrease and this transferred to self-paced movements. Regarding the center-of-pressure peak velocity, which is indicative of the efficiency of the postural actions generated in stabilizing posture, no difference appeared between the two sessions post-fatigue. This highlights an optimization of the postural actions when subjects first moved in self-paced conditions, smaller postural muscle activation levels resulting in similar postural consequences. In conclusion, the level of neuromuscular activity associated with the postural control is affected and can be

  6. Age-related changes in dynamic postural control and attentional demands are minimally affected by local muscle fatigue.

    Directory of Open Access Journals (Sweden)

    Anthony eRemaud

    2016-01-01

    Full Text Available Normal aging results in alterations in the visual, vestibular and somtaosensory systems, which in turn modify the control of balance. Muscle fatigue may exacerbate these age-related changes in sensory and motor functions, and also increase the attentional demands associated with dynamic postural control. The purpose of this study was to investigate the effect of aging on dynamic postural control and posture-related attentional demands before and after a plantar flexor fatigue protocol. Participants (young adults: n=15; healthy seniors: n=13 performed a dynamic postural task along the antero-posterior and the medio-lateral axes, with and without the addition of a simple reaction time task. The dynamic postural task consisted in following a moving circle on a computer screen with the representation of the center of pressure (COP. This protocol was repeated before and after a fatigue task where ankle plantarflexor muscles were targeted. The mean COP-target distance and the mean COP velocity were calculated for each trial. Cross-correlation analyses between the COP and target displacements were also performed. Reaction times were recorded during dual-task trials. Results showed that while young adults adopted an anticipatory control mode to move their COP as close as possible to the target center, seniors adopted a reactive control mode, lagging behind the target center. This resulted in longer COP-target distance and higher COP velocity in the latter group. Concurrently, reaction time increased more in seniors when switching from static stance to dynamic postural conditions, suggesting potential alterations in the central nervous system functions. Finally, plantar flexor muscle fatigue and dual-tasking had only minor effects on dynamic postural control of both young adults and seniors. Future studies should investigate why the fatigue-induced changes in quiet standing postural control do not seem to transfer to dynamic balance tasks.

  7. Age-Related Changes in Dynamic Postural Control and Attentional Demands are Minimally Affected by Local Muscle Fatigue

    Science.gov (United States)

    Remaud, Anthony; Thuong-Cong, Cécile; Bilodeau, Martin

    2016-01-01

    Normal aging results in alterations in the visual, vestibular and somtaosensory systems, which in turn modify the control of balance. Muscle fatigue may exacerbate these age-related changes in sensory and motor functions, and also increase the attentional demands associated with dynamic postural control. The purpose of this study was to investigate the effect of aging on dynamic postural control and posture-related attentional demands before and after a plantar flexor fatigue protocol. Participants (young adults: n = 15; healthy seniors: n = 13) performed a dynamic postural task along the antero-posterior (AP) and the medio-lateral (ML) axes, with and without the addition of a simple reaction time (RT) task. The dynamic postural task consisted in following a moving circle on a computer screen with the representation of the center of pressure (COP). This protocol was repeated before and after a fatigue task where ankle plantar flexor muscles were targeted. The mean COP-target distance and the mean COP velocity were calculated for each trial. Cross-correlation analyses between the COP and target displacements were also performed. RTs were recorded during dual-task trials. Results showed that while young adults adopted an anticipatory control mode to move their COP as close as possible to the target center, seniors adopted a reactive control mode, lagging behind the target center. This resulted in longer COP-target distance and higher COP velocity in the latter group. Concurrently, RT increased more in seniors when switching from static stance to dynamic postural conditions, suggesting potential alterations in the central nervous system (CNS) functions. Finally, plantar flexor muscle fatigue and dual-tasking had only minor effects on dynamic postural control of both young adults and seniors. Future studies should investigate why the fatigue-induced changes in quiet standing postural control do not seem to transfer to dynamic balance tasks. PMID:26834626

  8. Postural Control in Children with Dyslexia: Effects of Emotional Stimuli in a Dual-Task Environment.

    Science.gov (United States)

    Goulème, Nathalie; Gerard, Christophe-Loïc; Bucci, Maria Pia

    2017-08-01

    The aim of this study was to compare the visual exploration strategies used during a postural control task across participants with and without dyslexia. We simultaneously recorded eye movements and postural control while children were viewing different types of emotional faces. Twenty-two children with dyslexia and twenty-two aged-matched children without dyslexia participated in the study. We analysed the surface area, the length and the mean velocity of the centre of pressure for balance in parallel with visual saccadic latency, the number of saccades and the time spent in regions of interest. Our results showed that postural stability in children with dyslexia was weaker and the surface area of their centre of pressure increased significantly when they viewed an unpleasant face. Moreover, children with dyslexia had different strategies to those used by children without dyslexia during visual exploration, and in particular when they viewed unpleasant emotional faces. We suggest that lower performance in emotional face processing in children with dyslexia could be due to a difference in their visual strategies, linked to their identification of unpleasant emotional faces. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  9. Effect of vestibular neuritis on postural control using wavelets and fractal analysis.

    Science.gov (United States)

    Lorin, P; Manceau, C; Foubert, F

    2010-01-01

    What is the status of postural control a few months after an attack of vestibular neuritis (VN)? Using dynamic posturography and stabilometric signal treatment with wavelets and fractal analysis, we tried to answer this question by isolating the pathological postural parameters of VN. The study involved a group of 15 patients (GP) who suffered from VN and were compared to a group of control subjects (GC). Both groups underwent videonystagmography (VNG), dynamic posturography (PDY), and assessment using symptomatic scales (ES). GP and GC were comparable in terms of age mean, sex-ratio, average height and weight. The differences between GP and GC were the following videonystagmography criteria: Spontaneous nystagmus (NS) (P= 0.005), head shaking test (HST) (p= 0.001), vibratory test (TVO) (p= 0.009). There were also differences in the symptomatic scales scores for the vertigo symptom scale (VSS) (p= 0.011), the dizziness handicap inventory (DHI) (p= 0.001), and the short form 36 (SF36) (p= 0.01). All the 84 new parameters of both GP and GC differ. This difference was significant (p conditions were found to be non-discriminating. Vestibular neuritis affects new stabilometric parameters. These parameters are more adapted to the present setup compared to previous parameters which are used to analyse non-periodic oscillations of posture. They are important in follow-up and rehabilitation of patients.

  10. Proprioceptive control of posture : a review of new concepts

    NARCIS (Netherlands)

    Allum, JHJ; Carpenter, MG; Hulliger, M; Hadders-Algra, M; Bloem, Bastiaan R.

    1998-01-01

    The assumption that proprioceptive inputs from the lower legs are used to trigger balance and gait movements is questioned in this review (an outgrowth of discussions initiated during the Neural Control of Movement Satellite meeting held in Cozumel, Mexico, April 1997). Recent findings presented

  11. Postural control and shoulder steadiness in F-16 pilots

    DEFF Research Database (Denmark)

    Lange, Britt; Murray, Mike; Chreiteh, Shadi S

    2014-01-01

    BACKGROUND: During maneuvering, fighter pilots experience loads of up to 50-70 kg on their necks. Neck disorders are common and have been linked to impairment in muscle control. We conducted an intervention study introducing targeted training for 24 wk that reduced neck pain. The current study re...

  12. Postural control and shoulder steadiness in F-16 pilots

    DEFF Research Database (Denmark)

    Lange, Britt; Murray, Mike; Chreiteh, Shadi S

    2014-01-01

    BACKGROUND: During maneuvering, fighter pilots experience loads of up to 50-70 kg on their necks. Neck disorders are common and have been linked to impairment in muscle control. We conducted an intervention study introducing targeted training for 24 wk that reduced neck pain. The current study...

  13. Muscle networks: Connectivity analysis of EMG activity during postural control

    NARCIS (Netherlands)

    Boonstra, T.W.; Danna-Dos-Santos, A.; Xie, H-B; Roerdink, M.; Stins, J.F.; Breakspear, M.

    2015-01-01

    Understanding the mechanisms that reduce the many degrees of freedom in the musculoskeletal system remains an outstanding challenge. Muscle synergies reduce the dimensionality and hence simplify the control problem. How this is achieved is not yet known. Here we use network theory to assess the

  14. Coordinated alpha and gamma control of muscles and spindles in movement and posture

    Science.gov (United States)

    Li, Si; Zhuang, Cheng; Hao, Manzhao; He, Xin; Marquez, Juan C.; Niu, Chuanxin M.; Lan, Ning

    2015-01-01

    Mounting evidence suggests that both α and γ motoneurons are active during movement and posture, but how does the central motor system coordinate the α-γ controls in these tasks remains sketchy due to lack of in vivo data. Here a computational model of α-γ control of muscles and spindles was used to investigate α-γ integration and coordination for movement and posture. The model comprised physiologically realistic spinal circuitry, muscles, proprioceptors, and skeletal biomechanics. In the model, we divided the cortical descending commands into static and dynamic sets, where static commands (αs and γs) were for posture maintenance and dynamic commands (αd and γd) were responsible for movement. We matched our model to human reaching movement data by straightforward adjustments of descending commands derived from either minimal-jerk trajectories or human EMGs. The matched movement showed smooth reach-to-hold trajectories qualitatively close to human behaviors, and the reproduced EMGs showed the classic tri-phasic patterns. In particular, the function of γd was to gate the αd command at the propriospinal neurons (PN) such that antagonistic muscles can accelerate or decelerate the limb with proper timing. Independent control of joint position and stiffness could be achieved by adjusting static commands. Deefferentation in the model indicated that accurate static commands of αs and γs are essential to achieve stable terminal posture precisely, and that the γd command is as important as the αd command in controlling antagonistic muscles for desired movements. Deafferentation in the model showed that losing proprioceptive afferents mainly affected the terminal position of movement, similar to the abnormal behaviors observed in human and animals. Our results illustrated that tuning the simple forms of α-γ commands can reproduce a range of human reach-to-hold movements, and it is necessary to coordinate the set of α-γ descending commands for accurate

  15. A systematic review of the relationship between physical activities in sports or daily life and postural sway in upright stance.

    Science.gov (United States)

    Kiers, Henri; van Dieën, Jaap; Dekkers, Henk; Wittink, Harriët; Vanhees, Luc

    2013-11-01

    In many sports, maintaining balance is necessary to compete at a high level. Also, in many health problems, balance is impaired. Postural sway (PS) is often used as an indicator of upright balance control, and physical activity (PA) might enhance balance control. However, the relationship between PS and PA has never been systematically reviewed. Our objective was to summarize the evidence regarding the relationship between PS in upright bipedal and unipedal standing and PA. We conducted a literature search in MEDLINE, EmBase, CINAHL, the Cochrane Database, and PEDro, up to March 2012, with no limit on the starting date. Characteristics and methodological aspects of each article were extracted by two reviewers. We used centre of pressure (CoP) velocity, and variables related to the CoP area, to compare studies. A total of 39 articles were reviewed from an initial yield of 2,058. Of these 39 studies, 37 used a comparative design, one was a cohort study, and one was a randomized controlled trial. The main conclusion was that in general, sport practitioners sway less than controls, and high-level athletes sway less than low-level athletes. Additionally, we identified specific effects dependent on the use of vision, sport-specific postures, and frequency and duration of the (sports) activity. PS in unperturbed bipedal stance appears to have limited sensitivity to detect subtle differences between groups of healthy people.

  16. Simulation of aperiodic bipedal sprinting.

    Science.gov (United States)

    Celik, Huseyin; Piazza, Stephen J

    2013-08-01

    Synthesis of legged locomotion through dynamic simulation is useful for exploration of the mechanical and control variables that contribute to efficient gait. Most previous simulations have made use of periodicity constraints, a sensible choice for investigations of steady-state walking or running. Sprinting from rest, however, is aperiodic by nature and this aperiodicity is central to the goal of the movement, as performance is determined in large part by a rapid acceleration phase early in the race. The purpose of this study was to create a novel simulation of aperiodic sprinting using a modified spring-loaded inverted pendulum (SLIP) biped model. The optimal control problem was to find the set of controls that minimized the time for the model to run 20 m, and this problem was solved using a direct multiple shooting algorithm that converts the original continuous time problem into piecewise discrete subproblems. The resulting nonlinear programming problem was solved iteratively using a sequential quadratic programming method. The starting point for the optimizer was an initial guess simulation that was a slow alternating-gait "jogging" simulation developed using proportional-derivative feedback to control trunk attitude, swing leg angle, and leg retraction and extension. The optimized aperiodic sprint simulation solution yielded a substantial improvement in locomotion time over the initial guess (2.79 s versus 6.64 s). Following optimization, the model produced forward impulses at the start of the sprint that were four times greater than those of the initial guess simulation, producing more rapid acceleration. Several gait features demonstrated in the optimized sprint simulation correspond to behaviors of human sprinters: forward trunk lean at the start; straightening of the trunk during acceleration; and a dive at the finish. Optimization resulted in reduced foot contact times (0.065 s versus 0.210 s), but contact times early in the optimized

  17. 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.

  18. Postural adjustments in young ballet dancers compared to age matched controls.

    Science.gov (United States)

    Iunes, Denise H; Elias, Iara F; Carvalho, Leonardo C; Dionísio, Valdeci C

    2016-01-01

    The purpose of the study was to use photogrammetry to evaluate the posture of ballet practitioners compared to an age-matched control group. One hundred and eleven 7- to 24-year-old female volunteers were evaluated and were divided into two groups: the ballet practising group (n = 52) and the control group (n = 59), divided into three subgroups according to age and years of ballet experience. Dancers with 1-3 years experience compared to controls of the same age shows alterations in External Rotation Angle (P ballet experience, the Navicular Angle Left is smaller. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. The role of prefrontal cortex during postural control in Parkinsonian syndromes a functional near-infrared spectroscopy study.

    Science.gov (United States)

    Mahoney, Jeannette R; Holtzer, Roee; Izzetoglu, Meltem; Zemon, Vance; Verghese, Joe; Allali, Gilles

    2016-02-15

    Postural instability represents a main source of disability in Parkinsonian syndromes and its pathophysiology is poorly understood. Indirect probes (i.e., mental imagery) of brain involvement support the role of prefrontal cortex as a key cortical region for postural control in older adults with and without Parkinsonian syndromes. Using functional near infrared spectroscopy (fNIRs) as a direct online cortical probe, this study aimed to compare neural activation patterns in prefrontal cortex, postural stability, and their respective interactions, in (1) patients with Parkinsonian syndromes; (2) those with mild parkinsonian signs; (3) and healthy older adults. Among 269 non-demented older adults (76.41 ± 6.70 years, 56% women), 26 individuals presented with Parkinsonian syndromes (Unified Parkinson's disease rating scale (UPDRS): 11.08 ± 3.60), 117 had mild parkinsonian signs (UPDRS: 3.21 ± 2.49), and 126 individuals were included as a healthy control group. Participants were asked to stand upright and count silently for ten seconds while changes in oxygenated hemoglobin levels over prefrontal cortex were measured using fNIRs. We simultaneously evaluated postural stability with center of pressure velocity data recorded on an instrumented walkway. Compared to healthy controls and patients with mild parkinsonian signs, patients with Parkinsonian syndromes demonstrated significantly higher prefrontal oxygenation levels to maintain postural stability. The pattern of brain activation and postural control of participants with mild parkinsonian signs were similar to that of normal controls. These findings highlight the online role of the prefrontal cortex in postural control in patients with Parkinsonian syndromes and afford the opportunity to improve therapeutic options for postural instability. Copyright © 2016. Published by Elsevier B.V.

  20. Postural control and functional ankle stability in professional and amateur dancers.

    Science.gov (United States)

    Rein, Susanne; Fabian, Tobias; Zwipp, Hans; Rammelt, Stefan; Weindel, Stefan

    2011-08-01

    The aim of this study was to compare the postural control and functional ankle stability between professional and amateur dancers as well as controls. Thirty professional dancers were compared to thirty amateur dancers and thirty controls. All participants (n=90) completed a questionnaire. Range of motion (ROM), ankle position sense and peroneal reaction time (PRT) were measured. Postural control was investigated with the Biodex Stability System (BSS) for the stable level 8 and the unstable level 2. Professional dancers showed a significantly increased plantarflexion of both feet in comparison to all other groups (P ≤ 0.017). Even amateur dancers had a significantly increased plantarflexion of both feet in comparison to controls (P ≤ 0.017). The position sense test only showed significant differences between professionals, amateurs and controls at the position of 130° for the right leg (P ≤ 0.017). The PRT showed no significant differences among all groups except for the left peroneus brevis of amateur dancers in comparison to controls (P ≤ 0.017). Professional dancers had a significant better postural control in comparison to amateurs and controls for levels 8 and 2 at all tested positions (P ≤ 0.017). In addition, professional dancers had a specific balance distribution, whereas they balanced significantly more in the antero-lateral and less in the postero-medial part of their feet in comparison with amateur dancers and controls (P ≤ 0.017). Despite a greater ROM, professional dancers have a better control of postural stability due to a specific balance distribution. However, the position sense test and the PRT were not influenced by the profession. The specific work-related demands of ankle joints did not improve all components of functional ankle stability in professional dancers. Therefore, the inclusion of proprioceptive exercises in the daily training program is highly recommended, aiming to improve functional ankle stability and thus to

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

    Science.gov (United States)

    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.; hide

    2014-01-01

    The goal of the Functional Task Test study is to determine the effects of space flight on functional tests that are representative of high priority exploration mission tasks and to identify the key underlying physiological factors that contribute to decrements in performance. We are currently conducting studies on both International Space Station (ISS) astronauts experiencing up to 6 months of microgravity and subjects experiencing 70 days of 6??head-down bed-rest as an analog for space flight. Bed-rest provides the opportunity for us to investigate the role of prolonged axial body unloading in isolation from the other physiological effects produced by exposure to the microgravity environment of space flight. This allows us to parse out the contribution of the body unloading somatosensory component on functional performance. Both ISS crewmembers and bed-rest subjects were tested using a protocol that evaluated functional performance along with tests of postural and locomotor control before and after space flight and bed-rest, respectively. Functional tests included ladder climbing, hatch opening, jump down, manual manipulation of objects and tool use, seat egress and obstacle avoidance, recovery from a fall, and object translation tasks. Astronauts were tested three times before flight, and on 1, 6, and 30 days after landing. Bed-rest subjects were tested three times before bed-rest and immediately after getting up from bed-rest as well as 1, 6, and 12 days after re-ambulation. A comparison of bed-rest and space flight data showed a significant concordance in performance changes across all functional tests. Tasks requiring a greater demand for dynamic control of postural equilibrium (i.e. fall recovery, seat egress/obstacle avoidance during walking, object translation, jump down) showed the greatest decrement in performance. Functional tests with reduced requirements for postural stability showed less reduction in performance. Results indicate that body unloading

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

    Directory of Open Access Journals (Sweden)

    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.

  3. Postural alignment in children with bilateral spastic cerebral palsy using a bimanual interface for powered wheelchair control.

    Science.gov (United States)

    Liu, Wen-Yu; Chen, Fang-Jie; Lin, Yang-Hua; Kuo, Chung-Hsien; Lien, Hen-Yu; Yu, Yu-Jhih

    2014-01-01

    To examine postural alignment in children with bilateral spastic cerebral palsy while driving a powered wheelchair using both a unilateral joystick and an innovative bimanual interface. Cross-sectional study. A total of 20 children with bilateral spastic cerebral palsy (mean age 9.0 years (standard deviation 2.1); 11 with diplegia, 9 with quadriplegia) and 14 typically developing children (mean age 7.7 years (standard deviation 2.9)). All children drove the powered wheelchair in both the unilateral and bimanual conditions. The Seated Postural Control Measure quantified the postural alignment of subjects while driving the powered wheelchair. Statistical analysis was carried out using repeated measures analysis of variance and Spearman's rank correlation coefficient. As expected, typically developing children had better postural alignment in both driving conditions than children with cerebral palsy. Children with cerebral palsy demonstrated more symmetrical postural alignment while using the bimanual interface than when using the unilateral joystick. In addition, the severity of cerebral palsy correlated moderately with postural symmetry in both conditions. The results suggest that this innovative bimanual interface might be beneficial for promoting symmetrical postural alignment in some children with bilateral spastic cerebral palsy.

  4. The basic mechanics of bipedal walking lead to asymmetric behavior.

    Science.gov (United States)

    Gregg, Robert D; Degani, Amir; Dhaher, Yasin; Lynch, Kevin M

    2011-01-01

    This paper computationally investigates whether gait asymmetries can be attributed in part to basic bipedal mechanics independent of motor control. Using a symmetrical rigid-body model known as the compass-gait biped, we show that changes in environmental or physiological parameters can facilitate asymmetry in gait kinetics at fast walking speeds. In the environmental case, the asymmetric family of high-speed gaits is in fact more stable than the symmetric family of low-speed gaits. These simulations suggest that lower extremity mechanics might play a direct role in functional and pathological asymmetries reported in human walking, where velocity may be a common variable in the emergence and growth of asymmetry. © 2011 IEEE

  5. A functional synergistic model to explain postural control during precise visual tasks.

    Science.gov (United States)

    Bonnet, Cédrick T; Baudry, Stéphane

    2016-10-01

    In everyday life, individuals sometimes have to perform precise, or challenging, visual tasks in upright standing. Upright, one problem to perform precise saccades and fixations is that the body oscillates continuously in a mainly unpredictable way. Current cognitive models assume that the central nervous system should divide its attention to perform these 'dual tasks' because of limited attentional resources (keeping balance and performing the precise visual task). The problem with the concept of duality is that individuals (need to) succeed in precise visual tasks upright and should not be more unstable and inefficient - because of a division of attention - in these tasks. In our opinion, the central nervous system should work adaptively in a way that enables success in these tasks. Hence, instead of assuming 'duality' in cognitive processes, we suggest that i) a 'synergy' - or unification - between visual and postural processes may be required to succeed in precise visual tasks. Success in precise visual tasks upright would also require ii) the synergy to be based on two feedforward processes with the visual process being the leader; iii) individuals to reduce their postural sway to facilitate successful synergies; iiii) additional cognitive resources to link visual and postural processes. We discuss some literature findings consistent with these assumptions and summarize a recent validation of the synergistic model. In summary, both models of duality and synergy could be complementary and the present manuscript shows how they could be included in a higher-order, two directional, cognitive model of postural control. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Analysis of isokinetic muscle function and postural control in individuals with intermittent claudication

    Directory of Open Access Journals (Sweden)

    Morgan Lanzarin

    2016-02-01

    Full Text Available BACKGROUND: Intermittent claudication (IC is a debilitating condition that mostly affects elderly people. IC is manifested by a decrease in ambulatory function. Individuals with IC present with motor and sensory nerve dysfunction in the lower extremities, which may lead to deficits in balance. OBJECTIVE: This study aimed to measure postural control and isokinetic muscle function in individuals with intermittent claudication. METHOD: The study included 32 participants of both genders, 16 IC participants (mean age: 64 years, SD=6 and 16 healthy controls (mean age: 67 years, SD=5, which were allocated into two groups: intermittent claudication group (ICG and control group (CG. Postural control was assessed using the displacement and velocity of the center of pressure (COP during the sensory organization test (SOT and the motor control test (MCT. Muscle function of the flexor and extensor muscles of the knee and ankle was measured by an isokinetic dynamometer. Independent t tests were used to calculate the between-group differences. RESULTS: The ICG presented greater displacement (p =0.027 and speed (p =0.033 of the COP in the anteroposterior direction (COPap during the MCT, as well as longer latency (p =0.004. There were no between-group differences during the SOT. The ICG showed decreased muscle strength and power in the plantar flexors compared to the CG. CONCLUSION: Subjects with IC have lower values of strength and muscle power of plantiflexores, as well as changes in postural control in dynamic conditions. These individuals may be more vulnerable to falls than healthy subjects.

  7. Intervenção motora precoce ambulatorial para neonatos prematuros no controle postural = Early motor outpatient service intervention for postural control in preterm neonates

    Directory of Open Access Journals (Sweden)

    Almeida, Carla Skilhan de

    2008-01-01

    Full Text Available Objetivo: Verificar as aquisições motoras relacionadas ao desenvolvimento axial espontâneo não comunicativo, ou seja, controle postural e deslocamento. Isto foi feito através de um programa de intervenção motora fisioterapêutica precoce em neonatos prematuros nascidos no Hospital São Lucas - PUCRS. Materiais e Métodos: Tarefas de perseguição visual, manipulação de brinquedos e de controle postural, baseados no conceito Bobath, foram implementadas no programa interventivo. Todos os 5 prematuros que participaram deste estudo foram avaliados pelo serviço de fisioterapia por meio da Escala de Desenvolvimento do Comportamento da Criança no Primeiro Ano de Vida no ingresso do estudo e repetida a cada dois meses. Resultados: O estudo evidencia que não houve resultados estatisticamente significativos referentes às atividades posturais, de equilíbrio dinâmico e de deslocamento, mas os prematuros obtiveram progressão na classificação das avaliações. No primeiro mês da avaliação a mediana foi de 3 (classificação regular, já no terceiro e quinto mês de avaliação a mediana se manteve em 4 (classificação bom. Conclusão: A intervenção motora precoce proporcionou uma progressão na classificação da avaliação das aquisições motoras do desenvolvimento de cada prematuro, porém, não houve resultados estatisticamente significativos, referentes a atividades posturais, de equilíbrio dinâmico e de deslocamento

  8. Vehicle height and posture control of the electronic air suspension system using the hybrid system approach

    Science.gov (United States)

    Sun, Xiaoqiang; Cai, Yingfeng; Chen, Long; Liu, Yanling; Wang, Shaohua

    2016-03-01

    The electronic air suspension (EAS) system can improve ride comfort, fuel economy and handling safety of vehicles by adjusting vehicle height. This paper describes the development of a novel controller using the hybrid system approach to adjust the vehicle height (height control) and to regulate the roll and pitch angles of the vehicle body during the height adjustment process (posture control). The vehicle height adjustment system of EAS poses challenging hybrid control problems, since it features different discrete modes of operation, where each mode has an associated linear continuous-time dynamic. In this paper, we propose a novel approach to the modelling and controller design problem for the vehicle height adjustment system of EAS. The system model is described firstly in the hybrid system description language (HYSDEL) to obtain a mixed logical dynamical (MLD) hybrid model. For the resulting model, a hybrid model predictive controller is tuned to improve the vehicle height and posture tracking accuracy and to achieve the on-off statuses direct control of solenoid valves. The effectiveness and performance of the proposed approach are demonstrated by simulations and actual vehicle tests.

  9. Comparative Effects of Different Balance-Training-Progression Styles on Postural Control and Ankle Force Production: A Randomized Controlled Trial.

    Science.gov (United States)

    Cuğ, Mutlu; Duncan, Ashley; Wikstrom, Erik

    2016-02-01

    Despite the effectiveness of balance training, the exact parameters needed to maximize the benefits of such programs remain unknown. One such factor is how individuals should progress to higher levels of task difficulty within a balance-training program. Yet no investigators have directly compared different balance-training-progression styles. To compare an error-based progression (ie, advance when proficient at a task) with a repetition-based progression (ie, advance after a set amount of repetitions) style during a balance-training program in healthy individuals. Randomized controlled trial. Research laboratory. A total of 28 (16 women, 12 men) physically healthy young adults (age = 21.57 ± 3.95 years, height = 171.60 ± 11.03 cm, weight = 72.96 ± 16.18 kg, body mass index = 24.53 ± 3.7). All participants completed 12 supervised balance-training sessions over 4 weeks. Each session consisted of a combination of dynamic unstable-surface tasks that incorporated a BOSU ball and lasted about 30 minutes. Static balance from an instrumented force plate, dynamic balance as measured via the Star Excursion Balance Test, and ankle force production in all 4 cardinal planes of motion as measured with a handheld dynamometer before and after the intervention. Selected static postural-control outcomes, dynamic postural control, and ankle force production in all planes of motion improved (P .05) for any of the outcome measures. A 4-week balance-training program consisting of dynamic unstable-surface exercises on a BOSU ball improved dynamic postural control and ankle force production in healthy young adults. These results suggest that an error-based balance-training program is comparable with but not superior to a repetition-based balance-training program in improving postural control and ankle force production in healthy young adults.

  10. Effect of posture-control insoles on function in children with cerebral palsy: randomized controlled clinical trial.

    Science.gov (United States)

    Pasini Neto, Hugo; Grecco, Luanda André Collange; Christovão, Thaluanna Cl; Braun, Luiz Alfredo; Giannasi, Lilian Chrystiane; Salgado, Afonso Shiguemi Inoue; de Moura, Renata Calhes Franco; de Carvalho, Paulo de Tarso Camillo; Corrêa, João Cf; Sampaio, Luciana Mm; Galli, Manuela; Oliveira, Claudia Santos

    2012-10-04

    Cerebral palsy (CP) is a posture and movement disorder and different therapeutic modalities, such as the use of braces, have sought to favor selective motor control and muscle coordination in such patients. The aim of the proposed study is to determine the effect of the combination of posture-control insoles and ankle-foot orthoses (AFOs) improving functional limitation in children with CP. The sample will be composed of 24 children with CP between four and 12 years of age. After the signing of the statement of informed consent, the children will be randomly allocated to two groups: a control group using AFOs alone and an experimental group using both posture-control insoles and AFOs. Evaluations will be performed on five occasions: without any accessory (insoles or AFOs), immediately after, one month after, six months after and one year after AFOs or insole and AFOs use. The evaluation will involve the analysis of gait, static and functional balance, mobility and hypertonia. The three-dimensional assessment of gait will involve the eight-camera SMART-D SMART-D 140® system (BTS Engineering), two Kistler force plates (model 9286BA) and an eight-channel, wireless FREEEMG® electromyography (BTS Engineering). Static balance will be assessed using a Kistler force plate (model 9286BA). Clinical functional balance and mobility will be assessed using the Berg Balance Scale, Timed Up-and-Go Test and Six-Minute Walk Test. The posture-control insoles will be made of ethylene vinyl acetate, with thermal molding for fixation. The fixed orthoses will be made of polypropylene and attached to the ankle region (AFO). The results will be analyzed statistically, with the level significance set to 5% (p < 0.05). RBR6d342s (http://www.ensaiosclinicos.gov.br/news/).

  11. Effect of posture-control insoles on function in children with cerebral palsy: Randomized controlled clinical trial

    Directory of Open Access Journals (Sweden)

    Pasini Neto Hugo

    2012-10-01

    Full Text Available Abstract Introduction Cerebral palsy (CP is a posture and movement disorder and different therapeutic modalities, such as the use of braces, have sought to favor selective motor control and muscle coordination in such patients. The aim of the proposed study is to determine the effect of the combination of posture-control insoles and ankle-foot orthoses (AFOs improving functional limitation in children with CP. Methods/Design The sample will be composed of 24 children with CP between four and 12 years of age. After the signing of the statement of informed consent, the children will be randomly allocated to two groups: a control group using AFOs alone and an experimental group using both posture-control insoles and AFOs. Evaluations will be performed on five occasions: without any accessory (insoles or AFOs, immediately after, one month after, six months after and one year after AFOs or insole and AFOs use. The evaluation will involve the analysis of gait, static and functional balance, mobility and hypertonia. The three-dimensional assessment of gait will involve the eight-camera SMART-D SMART-D 140® system (BTS Engineering, two Kistler force plates (model 9286BA and an eight-channel, wireless FREEEMG® electromyography (BTS Engineering. Static balance will be assessed using a Kistler force plate (model 9286BA. Clinical functional balance and mobility will be assessed using the Berg Balance Scale, Timed Up-and-Go Test and Six-Minute Walk Test. The posture-control insoles will be made of ethylene vinyl acetate, with thermal molding for fixation. The fixed orthoses will be made of polypropylene and attached to the ankle region (AFO. The results will be analyzed statistically, with the level significance set to 5% (p Trial Registration Trial Registration Number: RBR6d342s (http://www.ensaiosclinicos.gov.br/news/

  12. The effect of kinesio® tape on vertical jump and dynamic postural control.

    Science.gov (United States)

    Nakajima, Mikiko A; Baldridge, Carolann

    2013-08-01

    Ankle injuries are one of the most common injuries among physically active individuals. The role of prophylactic ankle taping and bracing has been studied extensively. Kinesio(®) Tape (KT) is a somewhat new type of taping technique gaining popularity as both treatment and performance enhancement tool. However, there is limited research on the effect of KT on functional performance. The purpose of this study was to determine whether the application of Kinesio Tex(®) Tape had an effect on vertical jump and dynamic postural control in healthy young individuals. 52 healthy subjects free of ankle or lower extremity problems (28 males and 24 females; age: 22.12±2.08 years; height: 170.77±8.69 cm; weight: 69.90±12.03 kg) participated in the study. Subjects were randomly assigned to either the experimental group (KT with tension) or the control group (KT without tension). Vertical jump was measured using the VertiMetric device and dynamic postural control was assessed using the Star Excursion Balance Test (SEBT) under three conditions: (1) without taping; (2) immediately after taping; (3) 24 hours after taping with the taping remaining in situ. Three-way repeated measure ANOVA was conducted in order to identify differences between the experimental and the control group during the three conditions. Overall, there were no differences between groups in vertical jump maximum height, vertical jump average height, or the SEBT scores for the three time periods (pre-test, post-test, 24hrs-post-test). However, the main effect of KT was moderated by a significant gender interaction, resulting in a statistically significant effect of KT for the SEBT scores in the posterior-medial direction, F(1.72, 82.57) = 4.50, p = 0.018 and the medial direction, F(1.75, 83.81) = 4.27, p = 0.021. Follow-up analyses indicated that female subjects in the KT group had increased SEBT scores between three time periods when compared to the placebo group. KT application on the ankle neither decreased

  13. Postural control in children with typical development and children with profound hearing loss

    Directory of Open Access Journals (Sweden)

    Monteiro de Sousa AM

    2012-05-01

    Full Text Available Aneliza Maria Monteiro de Sousa,1 Jônatas de França Barros,2 Brígido Martins de Sousa Neto31Faculty of Health Sciences, University of Brasilia, Brasilia, Federal District, Brazil; 2Department of Physical Education at the Federal University of Rio Grande do Norte, Natal, Rio Grande do Norte, Brazil; 3University Center UNIEURO, Brasilia, Federal District, BrazilPurpose: To describe the behavior of the postural control in children with profound sensorineural hearing loss and compare the results of experimental tests with hearing children aged 7 to 10 years.Patients and methods: This is a cross-sectional study where 100 children were divided into experimental and control groups. We used a force platform, AccuSway Plus, where the tests were conducted under the experimental conditions: open base, eyes open (OBEO; open base, eyes closed (OBEC; closed base, eyes open (CBEO; closed base, eyes closed (CBEC. The body sway velocity (V of the center of pressure, the displacement in the anteroposterior direction (COPap and mediolateral (COPml of the center of pressure were the parameters to evaluate the postural control. For statistical analysis we used the nonparametric Mann–Whitney U test, with a significance level of 5%.Results: In comparisons of variables between the groups, the experimental group outperformed by at least 75% of the control group values. In terms of global trends, the experimental group shows higher values of body oscillations in all experimental conditions and variables evaluated. Children with hearing loss had poorer balance performance compared to the group of hearing. The inferential analysis revealed a statistically significant difference in the balance between deaf and hearing children in the OBEC experimental condition in relation to the COPml parameter (P = 0.04. There were no statistically significant differences in comparisons between the sexes when the groups were analyzed separately. The prevalence of unknown etiology

  14. Comparison of posture and balance in cancer survivors and age-matched controls.

    Science.gov (United States)

    Schmitt, Abigail C; Repka, Chris P; Heise, Gary D; Challis, John H; Smith, Jeremy D

    2017-12-01

    The combination of peripheral neuropathy and other treatment-associated side effects is likely related to an increased incidence of falls in cancer survivors. The purpose of this study was to quantify differences in postural stability between healthy age-matched controls and cancer survivors. Quiet standing under four conditions (eyes open/closed, rigid/compliant surface) was assessed in 34 cancer survivors (2 males, 32 females; age: 54(13) yrs., height: 1.62(0.07) m; mass: 78.5(19.5) kg) and 34 age-matched controls (5 males, 29 females; age: 54(15) yrs.; height: 1.62(0.08) m; mass: 72.8(21.1) kg). Center of pressure data were collected for 30s and the trajectories were analyzed (100Hz). Three-factor (group*surface*vision) mixed model MANOVAs with repeated measures were used to determine the effect of vision and surface on postural steadiness between groups. Cancer survivors exhibited larger mediolateral root-mean square distance and velocity of the center of pressure, as well as increased 95% confidence ellipse area (P<0.01) when compared with their age-matched counterparts. For example, when removing visual input, cancer survivors had an average increase in 95% confidence ellipse area of 91.8mm 2 while standing on a rigid surface compared to a 68.6mm 2 increase for the control group. No frequency-based center of pressure measures differed between groups. Cancer survivors exhibit decreased postural steadiness when compared with age-matched controls. For cancer survivors undergoing rehabilitation focused on existing balance deficits, a small subset of the center of pressure measures presented here can be used to track progress throughout the intervention and potentially mitigate fall risk. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Biomechanics of running indicates endothermy in bipedal dinosaurs.

    Directory of Open Access Journals (Sweden)

    Herman Pontzer

    Full Text Available BACKGROUND: One of the great unresolved controversies in paleobiology is whether extinct dinosaurs were endothermic, ectothermic, or some combination thereof, and when endothermy first evolved in the lineage leading to birds. Although it is well established that high, sustained growth rates and, presumably, high activity levels are ancestral for dinosaurs and pterosaurs (clade Ornithodira, other independent lines of evidence for high metabolic rates, locomotor costs, or endothermy are needed. For example, some studies have suggested that, because large dinosaurs may have been homeothermic due to their size alone and could have had heat loss problems, ectothermy would be a more plausible metabolic strategy for such animals. METHODOLOGY/PRINCIPAL FINDINGS: Here we describe two new biomechanical approaches for reconstructing the metabolic rate of 14 extinct bipedal dinosauriforms during walking and running. These methods, well validated for extant animals, indicate that during walking and slow running the metabolic rate of at least the larger extinct dinosaurs exceeded the maximum aerobic capabilities of modern ectotherms, falling instead within the range of modern birds and mammals. Estimated metabolic rates for smaller dinosaurs are more ambiguous, but generally approach or exceed the ectotherm boundary. CONCLUSIONS/SIGNIFICANCE: Our results support the hypothesis that endothermy was widespread in at least larger non-avian dinosaurs. It was plausibly ancestral for all dinosauriforms (perhaps Ornithodira, but this is perhaps more strongly indicated by high growth rates than by locomotor costs. The polarity of the evolution of endothermy indicates that rapid growth, insulation, erect postures, and perhaps aerobic power predated advanced "avian" lung structure and high locomotor costs.

  16. Do bimanual coordination, tool use, and body posture contribute equally to hand preferences in bonobos?

    Science.gov (United States)

    Bardo, Ameline; Pouydebat, Emmanuelle; Meunier, Hélène

    2015-05-01

    Approximately 90% of the human population is right-handed. The emergence of this hand preference in humans is thought to be linked to the ability to execute complex tasks and habitual bipedalism. In order to test these hypotheses, the present study explored, for the first time, hand preference in relation to both body posture (seated and bipedal) and task complexity (bimanual coordination and two tool use tasks of different complexity) in bonobos (Pan paniscus). Few studies have explored the effects of both posture and task complexity on handedness, and investigations with bonobos are scarce, particularly studies on tool use. Our study aims to overcome such a gap by addressing two main questions: 1) Does a bipedal posture increase the strength of hand preference and/or create a directional bias to the use of the right hand? 2) Independent of body posture, does task complexity increase the strength of the hand preference and/or create a directional bias to the use of the right hand? Our results show that independent of body posture, the more complex the task, the more lateralization occurred. Moreover, subjects tended to be right-handed for tasks involving tool use. However, posture had no significant effect on hand preference in the tasks tested here. Therefore, for a given task, bonobos were not more lateralized in a bipedal posture than in a seated one. Task complexity might thus have contributed more than bipedal posture to the emergence of human lateralization and the preponderance of right-handedness, although a larger sample size and more data are needed to be conclusive. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Long-term effects from bacterial meningitis in childhood and adolescence on postural control.

    Directory of Open Access Journals (Sweden)

    Hannes Petersen

    Full Text Available Bacterial meningitis in childhood is associated with cognitive deficiencies, sensorimotor impairments and motor dysfunction later in life. However, the long-term effects on postural control is largely unknown, e.g., whether meningitis subjects as adults fully can utilize visual information and adaptation to enhance stability. Thirty-six subjects (20 women, mean age 19.3 years treated in childhood or adolescence for bacterial meningitis, and 25 controls (13 women, mean age 25.1 years performed posturography with eyes open and closed under unperturbed and perturbed standing. The meningitis subjects were screened for subjective vertigo symptoms using a questionnaire, clinically tested with headshake and head thrust test, as well as their hearing was evaluated. Meningitis subjects were significantly more unstable than controls during unperturbed (p≤0.014 and perturbed standing, though while perturbed only with eyes open in anteroposterior direction (p = 0.034 whereas in lateral direction both with eyes open and closed (p<0.001. Meningitis subjects had poorer adaption ability to balance perturbations especially with eyes open, and they frequently reported symptoms of unsteadiness (88% of the subjects and dizziness (81%, which was found significantly correlated to objectively decreased stability. Out of the 36 subjects only 3 had unilateral hearing impairment. Hence, survivors of childhood bacterial meningitis may suffer long-term disorders affecting postural control, and would greatly benefit if these common late effects became generally known so treatments can be developed and applied.

  18. Improved postural control after slackline training is accompanied by reduced H-reflexes.

    Science.gov (United States)

    Keller, M; Pfusterschmied, J; Buchecker, M; Müller, E; Taube, W

    2012-08-01

    "Slacklining" represents a modern sports activity where people have to keep balance on a tightened ribbon. The first trials on the slackline result in uncontrollable lateral swing of the supporting leg. Training decreases those oscillations and therefore improves postural control. However, the underlying neural mechanisms are not known. Therefore, the present study aimed to highlight spinal adaptations going along with slackline training. Twenty-four subjects were either assigned to a training or a control group and postural control was assessed before and after the 10 training sessions. Additionally, soleus Hoffmann (H)-reflexes were elicited to evaluate changes in the excitability of the spinal reflex circuitry. Trained subjects were able to maintain balance on the slackline for at least 20 s (P<0.001) and reduced platform movements on the balance board (P<0.05). The H-reflexes were significantly diminished (P<0.05) while no changes occurred in the background electromyography (bEMG). The control group showed no significant changes. From a functional point of view the reflex reduction may serve to suppress uncontrollable reflex mediated joint oscillations. As the bEMG remained unchanged, presynaptic rather than post-synaptic mechanisms are speculated to be responsible for the changes in the Ia-afferent transmission. © 2011 John Wiley & Sons A/S.

  19. Long-Term Effects from Bacterial Meningitis in Childhood and Adolescence on Postural Control

    Science.gov (United States)

    Petersen, Hannes; Patel, Mitesh; Ingason, Einar F.; Einarsson, Einar J.; Haraldsson, Ásgeir; Fransson, Per-Anders

    2014-01-01

    Bacterial meningitis in childhood is associated with cognitive deficiencies, sensorimotor impairments and motor dysfunction later in life. However, the long-term effects on postural control is largely unknown, e.g., whether meningitis subjects as adults fully can utilize visual information and adaptation to enhance stability. Thirty-six subjects (20 women, mean age 19.3 years) treated in childhood or adolescence for bacterial meningitis, and 25 controls (13 women, mean age 25.1 years) performed posturography with eyes open and closed under unperturbed and perturbed standing. The meningitis subjects were screened for subjective vertigo symptoms using a questionnaire, clinically tested with headshake and head thrust test, as well as their hearing was evaluated. Meningitis subjects were significantly more unstable than controls during unperturbed (p≤0.014) and perturbed standing, though while perturbed only with eyes open in anteroposterior direction (p = 0.034) whereas in lateral direction both with eyes open and closed (pMeningitis subjects had poorer adaption ability to balance perturbations especially with eyes open, and they frequently reported symptoms of unsteadiness (88% of the subjects) and dizziness (81%), which was found significantly correlated to objectively decreased stability. Out of the 36 subjects only 3 had unilateral hearing impairment. Hence, survivors of childhood bacterial meningitis may suffer long-term disorders affecting postural control, and would greatly benefit if these common late effects became generally known so treatments can be developed and applied. PMID:25405756

  20. 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

  1. Decerebrate posture

    Science.gov (United States)

    ... be brain and nervous system injury and permanent brain damage, which can lead to: Coma Inability to communicate Paralysis Seizures Alternative Names Opisthotonos - decerebrate posture; Abnormal posturing - ...

  2. Surgically induced astigmatism after phacoemulsification with and without correction for posture-related ocular cyclotorsion: randomized controlled study.

    LENUS (Irish Health Repository)

    Dooley, Ian

    2012-02-01

    PURPOSE: To report the impact of posture-related ocular cyclotorsion on one surgeon\\'s surgically induced astigmatism (SIA) results and the variance in SIA. SETTING: Institute of Eye Surgery, Whitfield Clinic, Waterford, Ireland. METHODS: This prospective randomized controlled study included eyes that had phacoemulsification with intraocular lens implantation. Eyes were randomly assigned to have (intervention group) or not have (control group) correction for posture-related ocular cyclotorsion. In the intervention group, the clear corneal incision was placed precisely at the 120-degree meridian with instruments designed to correct posture-related ocular cyclotorsion. In the control group, the surgeon endeavored to place the incision at the 120-degree meridian, but without markings. RESULTS: The intervention group comprised 41 eyes and the control group, 61 eyes. The mean absolute SIA was 0.74 diopters (D) in the intervention group and 0.78 D in the control group; the difference between groups was not statistically significant (P>.5, unpaired 2-tailed Student t test). The variance in SIA was 0.29 D(2) and 0.31 D(2), respectively; the difference between groups was not statistically significant (P>.5, unpaired F test). CONCLUSIONS: Attempts to correct for posture-related ocular cyclotorsion did not influence SIA or its variance in a single-surgeon series. These results should be interpreted with full appreciation of the limitations of currently available techniques to correct for posture-related ocular cyclotorsion in the clinical setting.

  3. The Role of Postural Support in Young Adults' Control of Stationary Kicking

    Science.gov (United States)

    Sidaway, Ben; Bouchard, Matthew; Chasse, Julie; Dunn, Jonathan; Govoni, Andrea; McPherson, Breanne; Roy, Katherine; Anderson, David I.

    2017-01-01

    Purpose: The requirement for postural stability during the performance of motor skills has been clearly demonstrated in infants, but the necessity for such a postural substrate is not well documented in adults. The present study investigated the role of postural stability during a ballistic ball-kicking task in adults by providing varying degrees…

  4. Postural stability and ankle sprain history in athletes compared to uninjured controls

    NARCIS (Netherlands)

    Huurnink, A.; Fransz, D.P.; Kingma, I.; Verhagen, E.A.L.M.; van Dieen, J.H.

    2014-01-01

    Background Diminished postural stability is a risk factor for ankle sprain occurrence and ankle sprains result in impaired postural stability. To date, ankle sprain history has not been taken into account as a determinant of postural stability, while it could possibly specify subgroups of interest.

  5. Effects of hand posture on preparatory control processes and sensory modulations in tactile-spatial attention.

    Science.gov (United States)

    Eimer, Martin; Forster, Bettina; Fieger, Anne; Harbich, Stefanie

    2004-03-01

    Event-related brain potentials (ERPs) were measured to investigate spatial coordinate systems involved in the control of preparatory tactile-spatial orienting, and in subsequent attentional modulations of somatosensory processing. On each trial, a visual precue directed attention to the left or right hand, where infrequent tactile targets had to be detected. Hands were positioned either close together or wide apart. ERPs were recorded in the cue-target interval and in response to attended and unattended tactile non-targets. A frontal anterior directing attention negativity (ADAN) and a posterior late directing attention positivity (LDAP) were elicited in the cue-target interval contralateral to the direction of an attentional shift. The ADAN was unaffected by hand posture, but the LDAP was attenuated when hands were close together. N140 amplitudes were enhanced in response to tactile stimuli presented to the attended hand, and this effect was more pronounced when hands were wide apart. ADAN and LDAP are linked to separable anterior and posterior attentional control systems, which use coordinate systems based on somatotopic and external space, respectively. Effects of spatial attention on somatosensory stimulus processing are affected by variations in body posture. Our results demonstrate that representations of body locations in external space play a central role in the control of tactile attention.

  6. Differential effects of a visuospatial attention task on measures of postural control in young and older adults.

    Science.gov (United States)

    Peterson, Jeffrey J; Keenan, Kevin G

    2018-02-01

    The purpose of this study was to examine the influence of a visuospatial attention task on three measures of postural control in young and older adults. 20 young (19-36  years) and 20 older (67-91 years) adults performed a choice stepping response time (CSRT) task, a submaximal dorsiflexion force steadiness task, and quiet standing in 3 bilateral stances. All tasks were performed with and without a visuospatial (VS) attention task that involved visualizing a star moving within a 2 × 2 grid. CSRT increased with the addition of the VS task in both groups (p   .084). The findings suggest that visuospatial attention differentially affects postural control in young and older adults and the effect is task-specific. These findings suggest the need to include stepping and force control tasks to further determine what role visuospatial attention plays in postural control. Copyright © 2017. Published by Elsevier Ltd.

  7. Altered Dynamic Postural Control during Step Turning in Persons with Early-Stage Parkinson’s Disease

    Directory of Open Access Journals (Sweden)

    Jooeun Song

    2012-01-01

    Full Text Available Persons with early-stage Parkinson’s disease (EPD do not typically experience marked functional deficits but may have difficulty with turning tasks. Studies evaluating turning have focused on individuals in advanced stages of the disease. The purpose of this study was to compare postural control strategies adopted during turning in persons with EPD to those used by healthy control (HC subjects. Fifteen persons with EPD, diagnosed within 3 years, and 10 HC participated. Participants walked 4 meters and then turned 90°. Dynamic postural control was quantified as the distance between the center of pressure (COP and the extrapolated center of mass (eCOM. Individuals with EPD demonstrated significantly shorter COP-eCOM distances compared to HC. These findings suggest that dynamic postural control during turning is altered even in the early stages of PD.

  8. Human bipedal instability in tree canopy environments is reduced by "light touch" fingertip support.

    Science.gov (United States)

    Johannsen, L; Coward, S R L; Martin, G R; Wing, A M; Casteren, A van; Sellers, W I; Ennos, A R; Crompton, R H; Thorpe, S K S

    2017-04-25

    Whether tree canopy habitats played a sustained role in the ecology of ancestral bipedal hominins is unresolved. Some argue that arboreal bipedalism was prohibitively risky for hominins whose increasingly modern anatomy prevented them from gripping branches with their feet. Balancing on two legs is indeed challenging for humans under optimal conditions let alone in forest canopy, which is physically and visually highly dynamic. Here we quantify the impact of forest canopy characteristics on postural stability in humans. Viewing a movie of swaying branches while standing on a branch-like bouncy springboard destabilised the participants as much as wearing a blindfold. However "light touch", a sensorimotor strategy based on light fingertip support, significantly enhanced their balance and lowered their thigh muscle activity by up to 30%. This demonstrates how a light touch strategy could have been central to our ancestor's ability to avoid falls and reduce the mechanical and metabolic cost of arboreal feeding and movement. Our results may also indicate that some adaptations in the hand that facilitated continued access to forest canopy may have complemented, rather than opposed, adaptations that facilitated precise manipulation and tool use.

  9. Experimental System for Investigation of Visual Sensory Input in Postural Feedback Control

    Directory of Open Access Journals (Sweden)

    Jozef Pucik

    2012-01-01

    Full Text Available The human postural control system represents a biological feedback system responsible for maintenance of upright stance. Vestibular, proprioceptive and visual sensory inputs provide the most important information into the control system, which controls body centre of mass (COM in order to stabilize the human body resembling an inverted pendulum. The COM can be measured indirectly by means of a force plate as the centre of pressure (COP. Clinically used measurement method is referred to as posturography. In this paper, the conventional static posturography is extended by visual stimulation, which provides insight into a role of visual information in balance control. Visual stimuli have been designed to induce body sway in four specific directions – forward, backward, left and right. Stabilograms were measured using proposed single-PC based system and processed to calculate velocity waveforms and posturographic parameters. The parameters extracted from pre-stimulus and on-stimulus periods exhibit statistically significant differences.

  10. Postural neck pain: an investigation of habitual sitting posture, perception of 'good' posture and cervicothoracic kinaesthesia.

    Science.gov (United States)

    Edmondston, Stephen J; Chan, Hon Yan; Ngai, Gorman Chi Wing; Warren, M Linda R; Williams, Jonathan M; Glennon, Susan; Netto, Kevin

    2007-11-01

    Impairments of cervico-cephalic kinaesthesia and habitual forward head posture have been considered important in the aetiology of postural neck pain, yet these factors have not been specifically examined in a homogeneous clinical population. The objective of this study was to compare the habitual sitting posture (HSP), perception of good posture and postural repositioning error (PRE) of the cervico-thoracic (CT) spine in individuals with postural neck pain, with a matched group of asymptomatic subjects. Twenty-one subjects with postural neck pain and 22 asymptomatic control subjects were recruited into the study. An optical motion analysis system was used to measure the HSP and perceived 'good' sitting posture. PRE was measured over six trials where the subject attempted to replicate their self-selected 'good' posture. There was no difference between the groups in the HSP but significant differences were identified in the perception of 'good' posture. Posture repositioning error was higher for the head posture variables than for CT and shoulder girdle variables in both groups. However, there was no significant difference in posture repositioning error between groups for any of the posture measures. The findings suggest that individuals with postural neck pain may have a different perception of 'good' posture, but no significant difference in HSP or kinaesthetic sensibility compared with matched asymptomatic subjects.

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

    Science.gov (United States)

    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

  12. 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

  13. Rapid processing of haptic cues for postural control in blind subjects.

    Science.gov (United States)

    Schieppati, Marco; Schmid, Monica; Sozzi, Stefania

    2014-07-01

    Vision and touch rapidly lead to postural stabilization in sighted subjects. Is touch-induced stabilization more rapid in blind than in sighted subjects, owing to cross-modal reorganization of function in the blind? We estimated the time-period elapsing from onset of availability of haptic support to onset of lateral stabilization in a group of early- and late-onset blinds. Eleven blind (age 39.4 years±11.7SD) and eleven sighted subjects (age 30.0 years±10.0SD), standing eyes closed with feet in tandem position, touched a pad with their index finger and withdrew the finger from the pad in sequence. EMG of postural muscles and displacement of centre of foot pressure were recorded. The task was repeated fifty times, to allow statistical evaluation of the latency of EMG and sway changes following the haptic shift. Steady-state sway (with or without contact with pad, no haptic shift) did not differ between blind and sighted. On adding the haptic stimulus, EMG and sway diminished in both groups, but at an earlier latency (by about 0.5 s) in the blinds (p blinds. When the haptic stimulus was withdrawn, both groups increased EMG and sway at equally short delays. Blinds are rapid in implementing adaptive postural modifications when granted an external haptic reference. Fast processing of the stabilizing haptic spatial-orientation cues may be favoured by cortical plasticity in blinds. These findings add new information to the field of sensory-guided dynamic control of equilibrium in man. Copyright © 2013 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  14. Effects of regular Tai Chi practice and jogging on neuromuscular reaction during lateral postural control in older people.

    Science.gov (United States)

    Wang, Shao-Jun; Xu, Dong-Qing; Li, Jing-Xian

    2017-01-01

    This study examined the effects of regular Tai Chi practice and jogging on the neuromuscular activity of the trunk, hip, and ankle joint muscles of older people during lateral postural perturbation. A total of 42 older people participated in the study and formed the Tai Chi, jogging, and sedentary control groups. Electromyography signals were collected from the peroneus longus, anterior tibialis, gluteus medius, and erector spinae during unpredictable mediolateral perturbation. The Tai Chi group exhibited significantly faster latencies of the tibialis anterior and erector spinae than the control group. The jogging group showed a significantly shorter neuromuscular reaction time of the erector spinae than the control group. No significant difference was observed between the Tai Chi and jogging groups. Long-term regular Tai Chi practice enhanced the neuromuscular reaction of the erector spinae and tibialis anterior to lateral perturbation and will help timely posture correction when lateral postural distributions occur.

  15. Forearm posture and mobility in quadrupedal dinosaurs.

    Directory of Open Access Journals (Sweden)

    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.

  16. Forearm posture and mobility in quadrupedal dinosaurs.

    Science.gov (United States)

    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.

  17. Forearm Posture and Mobility in Quadrupedal Dinosaurs

    Science.gov (United States)

    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. PMID:24058633

  18. The evolutionary origins of obstructed labor: bipedalism, encephalization, and the human obstetric dilemma.

    Science.gov (United States)

    Wittman, Anna Blackburn; Wall, L Lewis

    2007-11-01

    Obstructed labor is a common complication of human childbirth. In parts of the world where access to emergency obstetric services is limited, obstructed labor is a major cause of maternal mortality. Women who survive the ordeal of prolonged obstructed labor often end up suffering from an obstetric vesicovaginal fistula or another serious birth injury that leaves them crippled for life. Compared with the other higher primates (chimpanzees, bonobos, gorillas, and orangutans), these problems are uniquely human. This article reviews the evolutionary origins of the human obstetric dilemma with special reference to the changes imposed on pelvic architecture by the assumption of upright, bipedal posture and locomotion. The subsequent development of progressively increasing brain size (encephalization) in hominins led to the present human obstetrical conundrum: how to balance the evolutionary advantage of bigger babies with larger brains against the presence of a narrow pelvis that is difficult for a fetus to traverse during labor.

  19. Motor-prediction improvements after virtual rehabilitation in geriatrics: frail patients reveal different learning curves for movement and postural control.

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    Kubicki, A; Bonnetblanc, F; Petrement, G; Mourey, F

    2014-01-01

    Postural control associated with self-paced movement is critical for balance in frail older adults. The present work aimed to investigate the effects of a 2D virtual reality-based program on postural control associated with rapid arm movement in this population. Participants in an upright standing position performed rapid arm-raising movements towards a target. Practice-related changes were assessed by pre- and post-test comparisons of hand kinematics and centre-of-pressure (CoP) displacement parameters measured in a training group and a control group. During these pre- and post-test sessions, patients have to reach towards yellow balls appearing on the screen, form a standardized upright position (with 15cm between the two malleoli). Training group patients took part in six sessions of virtual game. In this, patients were asked to reach their arm towards yellow balls appearing on the screen, from an upright position. After training, we observed improvements in arm movements and in the initial phase of CoP displacement, especially in the anticipatory postural adjustments. Learning curves for these two types of motor improvements showed different rates. These were continuous for the control of the arm movement, and discontinuous for the control of the CoP during the anticipatory postural adjustments. These results suggest that some level of motor (re)-learning is maintained in frail patients with low functional reserves. They also suggest that re-learning of anticipatory postural control (i.e. motor prediction) is less robust than explicit motor learning involved for the arm reaching. This last point should encourage clinicians to extend the training course duration, even if reaching movement improvements seems acquired, in order to automate these anticipatory postural activities. However, other studies should be done to measure the retention of these two types of learning on a longer-term period. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  20. ATLETAS DE TAEKWONDO TÊM MELHOR CONTROLE POSTURAL DO QUE ATLETAS DE HANDEBOL E FUTEBOL AMERICANO

    Directory of Open Access Journals (Sweden)

    Nelson Akio Shirabe

    Full Text Available RESUMO Introdução: O controle postural é um pré-requisito importante para o desempenho do atleta no esporte. Além disso, o sistema de controle postural contribui para a prevenção de lesões. Déficits nesse sistema podem levar a instabilidade corporal e sobrecarga das estruturas musculoesqueléticas, gerando disfunção e dor. Objetivos: A proposta deste estudo foi avaliar o controle postural em três diferentes modalidades esportivas: taekwondo, handebol e futebol americano. Métodos: Todos os atletas executaram o teste de equilíbrio unipodal sobre uma plataforma de força nos membros inferiores direito e esquerdo. Foram realizados três testes de trinta segundos cada, com os olhos abertos. A média dos três testes foi utilizada para mensurar os parâmetros de controle postural, centro de pressão e velocidade dos deslocamentos anteroposteriores e mediolaterais. Resultados: Diferenças significativas foram observadas entre os três grupos em todos os parâmetros analisados (P = <0,04. A análise post hoc revelou que os atletas de taekwondo tiveram melhor controle postural (P = < 0,035 dos membros inferiores em comparação com as outras duas modalidades. Não foram observadas diferenças significativas entre o handebol e o futebol americano. Conclusão: Os atletas do taekwondo têm melhor controle postural durante o teste de equilíbrio unipodal do que os atletas do handebol e do futebol americano.

  1. Evaluation of segmental postural characteristics during quiet standing in control and Idiopathic Scoliosis patients.

    Science.gov (United States)

    Zabjek, Karl F; Leroux, Michel A; Coillard, Christine; Rivard, Charles-H; Prince, François

    2005-06-01

    The complex skeletal deformations that accompany Idioapthic Scoliosis pose a challenge to the clinician to non-invasively discriminate Idiopathic Scoliosis patients from children with no pathology. Therefore, the focus of this study is to non-invasively evaluate the position and amplitude of displacement of the pelvis, shoulders and thorax during quiet standing of Idiopathic Scoliosis patients and control subjects. The quiet standing posture of 18 healthy adolescent females and 22 Idiopathic Scoliosis subjects was evaluated using an Optotrak 3020 position sensor over a period of 120 s, with 4 repeat trials. Outcome measures included the mean position, root mean square amplitude and range over the duration of 120 s trials for both linear and angular measures of the pelvis, thorax and shoulders. Appropriate sample times were chosen and evaluated for stability over the 120 s period, and between trial reliability was evaluated. There was a significant difference between groups for the mean position of the shoulder blade rotation in reference to the base of support and to the pelvis. The Idiopathic Scoliosis patients had a significantly larger root mean square amplitude of anterior-posterior displacement of the T1 and S1 spinous processes in reference to the base of support. There was no difference between the sample durations to estimate the mean position of the body segments, however the root mean square increased significantly. This study demonstrates that postural abnormalities are evident during quiet standing in Idiopathic Scoliosis patients.

  2. Control of vertical posture while standing on a sliding board and pushing an object.

    Science.gov (United States)

    Lee, Yun-Ju; Chen, Bing; Liang, Jing-Nong; Aruin, Alexander S

    2018-03-01

    Voluntary pushing or translation perturbation of the support surface each induces a body perturbation that affects postural control. The objective of the study was to investigate anticipatory (APA) and compensatory (CPA) postural adjustments when pushing an object (that induces self-initiated perturbation) and standing on a sliding board (that induces translational perturbation). Thirteen healthy young participants were instructed to push a handle with both hands while standing on a sliding board that was either free to move in the anterior-posterior direction or stationary. Electromyographic activity (EMG) of trunk and lower extremity muscles, center of pressure (COP) displacements, and the forces exerted by the hand were recorded and analyzed during the APA and CPA phases. When the sliding board was free to move during pushing (translation perturbation), onsets of activity of ventral leg muscles and COP displacement were delayed as compared to pushing when standing on a stationary board. Moreover, magnitudes of shank muscle activity and the COP displacement were decreased. When pushing heavier weight, magnitudes of muscle activity, COP displacement, and pushing force increased. The magnitude of activity of the shank muscles during the APA and CPA phases in conditions with translational perturbation varied with the magnitude of the pushing weight. The outcome of the study suggests that the central nervous system prioritizes the pushing task while attenuates the source of additional perturbation induced by translation perturbation. These results could be used in the development of balance re-training paradigms involving pushing weight while standing on a sliding surface.

  3. Closed-loop control of trunk posture improves locomotion through the regulation of leg proprioceptive feedback after spinal cord injury.

    Science.gov (United States)

    Moraud, Eduardo Martin; von Zitzewitz, Joachim; Miehlbradt, Jenifer; Wurth, Sophie; Formento, Emanuele; DiGiovanna, Jack; Capogrosso, Marco; Courtine, Grégoire; Micera, Silvestro

    2018-01-08

    After spinal cord injury (SCI), sensory feedback circuits critically contribute to leg motor execution. Compelled by the importance to engage these circuits during gait rehabilitation, assistive robotics and training protocols have primarily focused on guiding leg movements to reinforce sensory feedback. Despite the importance of trunk postural dynamics on gait and balance, trunk assistance has comparatively received little attention. Typically, trunk movements are either constrained within bodyweight support systems, or manually adjusted by therapists. Here, we show that real-time control of trunk posture re-established dynamic balance amongst bilateral proprioceptive feedback circuits, and thereby restored left-right symmetry, loading and stepping consistency in rats with severe SCI. We developed a robotic system that adjusts mediolateral trunk posture during locomotion. This system uncovered robust relationships between trunk orientation and the modulation of bilateral leg kinematics and muscle activity. Computer simulations suggested that these modulations emerged from corrections in the balance between flexor- and extensor-related proprioceptive feedback. We leveraged this knowledge to engineer control policies that regulate trunk orientation and postural sway in real-time. This dynamical postural interface immediately improved stepping quality in all rats regardless of broad differences in deficits. These results emphasize the importance of trunk regulation to optimize performance during rehabilitation.

  4. Theoretical analysis of the state of balance in bipedal walking.

    Science.gov (United States)

    Firmani, Flavio; Park, Edward J

    2013-04-01

    This paper presents a theoretical analysis based on classic mechanical principles of balance of forces in bipedal walking. Theories on the state of balance have been proposed in the area of humanoid robotics and although the laws of classical mechanics are equivalent to both humans and humanoid robots, the resulting motion obtained with these theories is unnatural when compared to normal human gait. Humanoid robots are commonly controlled using the zero moment point (ZMP) with the condition that the ZMP cannot exit the foot-support area. This condition is derived from a physical model in which the biped must always walk under dynamically balanced conditions, making the centre of pressure (CoP) and the ZMP always coincident. On the contrary, humans follow a different strategy characterized by a 'controlled fall' at the end of the swing phase. In this paper, we present a thorough theoretical analysis of the state of balance and show that the ZMP can exit the support area, and its location is representative of the imbalance state characterized by the separation between the ZMP and the CoP. Since humans exhibit this behavior, we also present proof-of-concept results of a single subject walking on an instrumented treadmill at different speeds (from slow 0.7 m/s to fast 2.0 m/s walking with increments of 0.1 m/s) with the motion recorded using an optical motion tracking system. In order to evaluate the experimental results of this model, the coefficient of determination (R2) is used to correlate the measured ground reaction forces and the resultant of inertial and gravitational forces (anteroposterior R² = 0.93, mediolateral R² = 0.89, and vertical R² = 0.86) indicating that there is a high correlation between the measurements. The results suggest that the subject exhibits a complete dynamically balanced gait during slow speeds while experiencing a controlled fall (end of swing phase) with faster speeds. This is quantified with the root-mean-square deviation (RMSD

  5. Center of pressure (COP) during the Postural Balance Control of High-Heeled Woman.

    Science.gov (United States)

    Cho, W; Choi, H

    2005-01-01

    This study addressed the effect of balance control problems of the high-heeled women. Clinical relationships have been proposed linking foot ailments or pain to wearing high heels, yet little quantitative research has been done on the relationship between bare foot and high feeled foot. The purposes of this study were to objectively quantify the displacements and velocities of center-of- pressure (COP) of body during two-way waist pulling and to compare the differences between barefooted and high-heeled situations. We used a waist pulling system which has three different magnitudes to sway the subjects. We found that the kinematic information of barefooted and high-heeled women's COP is very important in understanding the mechanism of postural balance control of women in every-day life. In the high-heeled's case, the displacement of COP increases in 200% as against bare footed. Also the velocity variation of COP grows two times than the bare footed.

  6. Fractal time series analysis of postural stability in elderly and control subjects

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    Doussot Michel

    2007-05-01

    Full Text Available Abstract Background The study of balance using stabilogram analysis is of particular interest in the study of falls. Although simple statistical parameters derived from the stabilogram have been shown to predict risk of falls, such measures offer little insight into the underlying control mechanisms responsible for degradation in balance. In contrast, fractal and non-linear time-series analysis of stabilograms, such as estimations of the Hurst exponent (H, may provide information related to the underlying motor control strategies governing postural stability. In order to be adapted for a home-based follow-up of balance, such methods need to be robust, regardless of the experimental protocol, while producing time-series that are as short as possible. The present study compares two methods of calculating H: Detrended Fluctuation Analysis (DFA and Stabilogram Diffusion Analysis (SDA for elderly and control subjects, as well as evaluating the effect of recording duration. Methods Centre of pressure signals were obtained from 90 young adult subjects and 10 elderly subjects. Data were sampled at 100 Hz for 30 s, including stepping onto and off the force plate. Estimations of H were made using sliding windows of 10, 5, and 2.5 s durations, with windows slid forward in 1-s increments. Multivariate analysis of variance was used to test for the effect of time, age and estimation method on the Hurst exponent, while the intra-class correlation coefficient (ICC was used as a measure of reliability. Results Both SDA and DFA methods were able to identify differences in postural stability between control and elderly subjects for time series as short as 5 s, with ICC values as high as 0.75 for DFA. Conclusion Both methods would be well-suited to non-invasive longitudinal assessment of balance. In addition, reliable estimations of H were obtained from time series as short as 5 s.

  7. Referent control of the orientation of posture and movement in the gravitational field.

    Science.gov (United States)

    Mullick, Aditi A; Turpin, Nicolas A; Hsu, Szu-Chen; Subramanian, Sandeep K; Feldman, Anatol G; Levin, Mindy F

    2018-02-01

    This study addresses the question of how posture and movement are oriented with respect to the direction of gravity. It is suggested that neural control levels coordinate spatial thresholds at which multiple muscles begin to be activated to specify a referent body orientation (RO) at which muscle activity is minimized. Under the influence of gravity, the body is deflected from the RO to an actual orientation (AO) until the emerging muscle activity and forces begin to balance gravitational forces and maintain body stability. We assumed that (1) during quiet standing on differently tilted surfaces, the same RO and thus AO can be maintained by adjusting activation thresholds of ankle muscles according to the surface tilt angle; (2) intentional forward body leaning results from monotonic ramp-and-hold shifts in the RO; (3) rhythmic oscillation of the RO about the ankle joints during standing results in body swaying. At certain sway phases, the AO and RO may transiently overlap, resulting in minima in the activity of multiple muscles across the body. EMG kinematic patterns of the 3 tasks were recorded and explained based on the RO concept that implies that these patterns emerge due to referent control without being pre-programmed. We also confirmed the predicted occurrence of minima in the activity of multiple muscles at specific body configurations during swaying. Results re-affirm previous rejections of model-based computational theories of motor control. The role of different descending systems in the referent control of posture and movement in the gravitational field is considered.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  10. Study of age-related changes in postural control during quiet standing through Linear Discriminant Analysis

    Directory of Open Access Journals (Sweden)

    Andrade Adriano O

    2009-11-01

    Full Text Available Abstract Background The human body adopts a number of strategies to maintain an upright position. The analysis of the human balance allows for the understanding and identification of such strategies. The displacement of the centre of pressure (COP is a measure that has been successfully employed in studies regarding the postural control. Most of these investigations are related to the analysis of individuals suffering from neuromuscular disorders. Recent studies have shown that the elderly population is growing very fast in many countries all over the world, and therefore, researches that try to understand changes in this group are required. In this context, this study proposes the analysis of the postural control, measured by the displacement of the COP, in groups of young and elderly adults. Methods In total 59 subjects participated of this study. They were divided into seven groups according to their age. The displacement of the COP was collected for each subject standing on a force plate. Two experimental conditions, of 30 seconds each, were investigated: opened eyes and closed eyes. Traditional and recent digital signal processing tools were employed for feature computation from the displacement of the COP. Statistical analyses were carried out in order to identify significant differences between the features computed from the distinct groups that could allow for their discrimination. Results Our results showed that Linear Discrimination Analysis (LDA, which is one of the most popular feature extraction and classifier design techniques, could be successfully employed as a linear transformation, based on the linear combination of standard features for COP analysis, capable of estimating a unique feature, so-called LDA-value, from which it was possible to discriminate the investigated groups and show a high correlation between this feature and age. Conclusion These results show that the analysis of features computed from the displacement of

  11. Effectiveness of an exercise program on postural control in frail older adults

    Directory of Open Access Journals (Sweden)

    Alfieri FM

    2012-12-01

    Full Text Available Fábio Marcon Alfieri,1,2 Marcelo Riberto,3 Àngels Abril-Carreres,4 Maria Boldó-Alcaine,4 Elisabet Rusca-Castellet,4 Roser Garreta-Figuera,4 Linamara Rizzo Battistella51São Paulo Adventist University Center, São Paulo, Brazil; 2Institute of Physical and Rehabilitation Medicine Hospital of Clinics, University of São Paulo, Brazil; 3School of Medicine in Ribeirão Preto, University of São Paulo, Brazil; 4University Hospital Mútua Terrassa Department of Rehabilitation, University of Barcelona, Barcelona, Spain; 5School of Medicine, Institute of Physical Medicine and Rehabilitation, Clinics Hospital of University of São Paulo, São Paulo, BrazilBackground: Exercise programs have proved to be helpful for frail older adults. This study aimed to investigate the effects of an exercise program with a focus on postural control exercises in frail older adults.Method: Twenty-six older adults (76.7 ± 4.9 years deemed clinically stable, chosen from the Falls Unit, University Hospital Mútua Terrassa, Barcelona, Spain, participated in this single-group study. Volunteers' postural control was evaluated using the Timed Up and Go test (TUG and the Guralnik test battery, and their static and dynamic posturography were evaluated using the Synapsys Posturography System®. These evaluations were performed before and after the intervention program, which included an educational session and two weekly 1-hour sessions over an 8-week period of stretching exercises, proprioception, balance, and motor coordination. Data were analyzed using the Student's t-test or the Wilcoxon test, with a significance level of 5%.Results: The TUG and Guralnik tests did not show significant differences. Concerning static posturography, there was improvement in the base of support (P = 0.006, anteroposterior displacement with eyes open (P = 0.02 and closed (P = 0.03, and the total amplitude of the center of pressure with eyes closed (P = 0.02. Regarding dynamic posturography, a

  12. Posture and lumbar puncture headache: a controlled trial in 50 patients.

    OpenAIRE

    Handler, C E; Smith, F R; Perkin, G D; Rose, F C

    1982-01-01

    A prospective single blind trial in 50 patients was performed to investigate the effect of posture on post lumbar puncture headache (LPH). A difference between the frequency of headache at five hours between the two groups (prone for four hours, versus 30 degrees head down tilt for 30 minutes followed by supine posture for 3 1/2 hours) did not reach significance. These findings do not support the suggestion that a prone posture, by possibly reducing cerebrospinal fluid (CSF) leakage, signific...

  13. Postural Control in Workplace Safety: Role of Occupational Footwear and Workload

    OpenAIRE

    Harish Chander; John C. Garner; Chip Wade; Adam C. Knight

    2017-01-01

    Maintaining postural stability is crucial, especially in hazardous occupational environments. The purpose of the study was to assess the role of three occupational footwear (low top shoe (LT); tactical work boot (TB) and steel-toed work boot (WB)) on postural stability when exposed to an occupational workload (4-h) involving standing/walking using the sensory organization test (SOT) equilibrium (EQ) scores and comparing current results with previously published postural sway variables from th...

  14. A fuzzy logic model for hand posture control using human cortical activity recorded by micro-ECog electrodes.

    Science.gov (United States)

    Vinjamuri, R; Weber, D J; Degenhart, A D; Collinger, J L; Sudre, G P; Adelson, P D; Holder, D L; Boninger, M L; Schwartz, A B; Crammond, D J; Tyler-Kabara, E C; Wang, W

    2009-01-01

    This paper presents a fuzzy logic model to decode the hand posture from electro-cortico graphic (ECoG) activity of the motor cortical areas. One subject was implanted with a micro-ECoG electrode array on the surface of the motor cortex. Neural signals were recorded from 14 electrodes on this array while Subject participated in three reach and grasp sessions. In each session, Subject reached and grasped a wooden toy hammer for five times. Optimal channels/electrodes which were active during the task were selected. Power spectral densities of optimal channels averaged over a time period of 1/2 second before the onset of the movement and 1 second after the onset of the movement were fed into a fuzzy logic model. This model decoded whether the posture of the hand is open or closed with 80% accuracy. Hand postures along the task time were decoded by using the output from the fuzzy logic model by two methods (i) velocity based decoding (ii) acceleration based decoding. The latter performed better when hand postures predicted by the model were compared to postures recorded by a data glove during the experiment. This fuzzy logic model was imported to MATLABSIMULINK to control a virtual hand.

  15. Postural Effects of Vestibular Manipulation Depend on the Physical Activity Status.

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    Julien Maitre

    Full Text Available The purpose of this study was to compare the effects of galvanic vestibular stimulation (GVS on postural control for participants of different physical activity status (i.e. active and non-active. Two groups of participants were recruited: one group of participants who regularly practised sports activities (active group, n = 17, and one group of participants who did not practise physical and/or sports activities (non-active group, n = 17. They were compared in a reference condition (i.e bipedal stance with eyes open and four vestibular manipulation condition (i.e. GVS at 0.5 mA and 3 mA, in accordance with two designs lasting 20 seconds. The centre of foot pressure displacement velocities were compared between the two groups. The main results indicate that the regular practice of sports activities counteracts postural control disruption caused by GVS. The active group demonstrated better postural control than the non-active group when subjected to higher vestibular manipulation. The active group may have developed their ability to reduce the influence of inaccurate vestibular signals. The active participants could identify the relevant sensory input, thought a better central integration, which enables them to switch faster between sensory inputs.

  16. Postural control strategies during single limb stance following acute lateral ankle sprain.

    Science.gov (United States)

    Doherty, Cailbhe; Bleakley, Chris; Hertel, Jay; Caulfield, Brian; Ryan, John; Delahunt, Eamonn

    2014-06-01

    Single-limb stance is maintained via the integration of visual, vestibular and somatosensory afferents. Musculoskeletal injury challenges the somatosensory system to reweight distorted sensory afferents. This investigation supplements kinetic analysis of eyes-open and eyes-closed single-limb stance tasks with a kinematic profile of lower limb postural orientation in an acute lateral ankle sprain group to assess the adaptive capacity of the sensorimotor system to injury. Sixty-six participants with first-time acute lateral ankle sprain completed a 20-second eyes-open single-limb stance task on their injured and non-injured limbs (task 1). Twenty-three of these participants successfully completed the same 20-second single-limb stance task with their eyes closed (task 2). A non-injured control group of 19 participants completed task 1, with 16 completing task 2. 3-dimensional kinematics of the hip, knee and ankle joints, as well as associated fractal dimension of the center-of-pressure path were determined for each limb during these tasks. Between trial analyses revealed significant differences in stance limb kinematics and fractal dimension of the center-of-pressure path for task 2 only. The control group bilaterally assumed a position of greater hip flexion compared to injured participants on their side-matched "involved"(7.41 [6.1°] vs 1.44 [4.8]°; η(2)=.34) and "uninvolved" (9.59 [8.5°] vs 2.16 [5.6°]; η(2)=.31) limbs, with a greater fractal dimension of the center-of-pressure path (involved limb=1.39 [0.16°] vs 1.25 [0.14°]; uninvolved limb=1.37 [0.21°] vs 1.23 [0.14°]). Bilateral impairment in postural control strategies present following a first time acute lateral ankle sprain. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Specificity of foot configuration during bipedal stance in ballet dancers.

    Science.gov (United States)

    Casabona, Antonino; Leonardi, Giuseppa; Aimola, Ettore; La Grua, Giovanni; Polizzi, Cristina Maria; Cioni, Matteo; Valle, Maria Stella

    2016-05-01

    Learning highly specialized upright postures may be of benefit for more common as well as for novel stances. In this study, we asked whether this generalization occurs with foot configurations previously trained or depends on a generic increase in balance difficulty. We also explored the possibility that the benefit may concern not only the level of postural performance but also the structural organization of the upright standing. Ten elite professional ballet dancers were compared to ten untrained subjects, measuring the motion of the center of pressure (COP) across a set of five stances with different foot configurations. The balance stability was measured computing the area, the sway path, and the root mean square of the COP motion, whereas the structure of the postural control was assessed by compute approximate entropy, fractal dimension and the mean power frequency. The foot position included common and challenging stances, with the level of difficulty changed across the configurations. Among these conditions, only one foot configuration was familiar to the dancers. Statistically significant differences between the two groups, for all the parameters, were observed only for the stance with the foot position familiar to the dancers. Stability and structural parameters exhibited comparable differences. We concluded that the benefit from classical ballet is limited to a specific foot configuration, regardless of the level of stance difficulty or the component of postural control. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Posture control with a neural network of a diagnostic robot manipulator; Neural network ni yoru haikan shindan robot manipulator no shisei seigyo

    Energy Technology Data Exchange (ETDEWEB)

    Abe, Y. [Shinryo Corp., Tokyo (Japan); Hara, F.; Hosokai, H.; Kojima, T. [Science University of Tokyo, Tokyo (Japan)

    1997-09-25

    A robot manipulator has been investigated, by which non-destructive diagnostic tests of a pipe-line can be automatically conducted. This robot manipulator has five degrees of freedom, and can set up an ultrasonic probe for diagnosis attached at the surface of pipe at various angles and with various forces. The manipulator is controlled through the feedback of variation of reflected ultrasonic wave with the contact force of probe. Using a neural network, the manipulator can smoothly shift its posture in the optimum sensing state from the initial posture. For the measuring experiment using a pipe, the posture control and the force control were evaluated. The posture control error was around 0.4 degree. The target allowable error 0.5 degree was achieved. For the force control, it was demonstrated that the follow-up property of contact force to the target value can be enhanced by increasing the intermediate posture number. 3 refs., 13 figs.

  19. 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.

  20. Effects of fatiguing isometric and isokinetic ankle exercises on postural control while standing on firm and compliant surfaces

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    Bisson Etienne J

    2012-06-01

    Full Text Available Abstract Background Fatiguing exercises used across studies to induce alterations in postural control are diverse and may explain the different findings reported. This study aimed to compare the effects of two types of fatiguing plantarflexion exercises on postural control on a firm and a compliant surface. Ten healthy young men (29 ± 4 years were asked to stand as steadily as possible for 30 s, blindfolded with feet together, on a firm and a compliant surface before and immediately after an isometric and an isokinetic fatiguing exercise. Results Maximal force reduction due to fatigue was found significant but similar between exercises. No significant difference was found between the fatiguing exercises on all Center of Pressure (CoP parameters. Both fatiguing exercises induced increases in CoP excursion area, CoP variability and CoP velocity in both planes (antero-posterior, mediolateral on the compliant surface. On the firm surface, both fatiguing exercises only induced increases in CoP variability and CoP velocity in the fatigued plane (antero-posterior. Conclusions Isometric and isokinetic fatiguing exercises, when producing a similar level of force reduction, induce similar decreases in postural control. The effects of fatigue on postural control in healthy young men are more pronounced when standing on a compliant surface, i.e. when proprioceptive information at the ankle is altered.

  1. The Effects of Functional Knee Brace on Postural Control in Patients Who Underwent Anterior Cruciate Ligament Reconstruction

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    Salehi

    2016-09-01

    Full Text Available Background The current study aimed to evaluate the postural control in patients underwent anterior cruciate ligament reconstruction pre and post wearing functional knee brace. Methods Eighteen athletes undergone unilateral anterior cruciate ligament reconstruction included in the study. They had unilateral anterior cruciate ligament reconstruction at least six months before session test. Postural control was assessed pre and post wearing custom-fit functional knee brace using a posturographic platform prokin 254. The balance tests included: 1 standing on prokin platform with eyes open/closed on anterior cruciate ligament reconstruction limb, 2 standing on prokin platform with eyes open/closed on both limbs. The standard deviation (SD of body sway along the anteroposterior (AP and mediolateral (ML axis, mean velocity of center of pressure (COP along AP/ ML axis and the area ellipse (measured in 2 mm were calculated. Results Results of the paired T-test revealed a significant effect on selected postural control variables for the brace conditions especially in low challengeable conditions (double leg, eyes open test situations (P < 0.05. But in high challengeable conditions this effect was not significant. Conclusions Functional knee brace improved postural control in the simple balancing task in the subjects with anterior cruciate ligament reconstruction. But this improvement in more difficult balancing task was limited.

  2. The Efficacy of a Perceptive Rehabilitation on Postural Control in Patients with Chronic Nonspecific Low Back Pain

    Science.gov (United States)

    Paolucci, Teresa; Fusco, Augusto; Iosa, Marco; Grasso, Maria R.; Spadini, Ennio; Paolucci, Stefano; Saraceni, Vincenzo M.; Morone, Giovanni

    2012-01-01

    Patients with chronic low back pain have a worse posture, probably related to poor control of the back muscles and altered perception of the trunk midline. The aim of this study was to evaluate the efficacy of a perceptive rehabilitation in terms of stability and pain relief in patients with chronic nonspecific low back pain. Thirty patients were…

  3. Interference of Different Types of Seats on Postural Control System during a Forward-Reaching Task in Individuals with Paraplegia

    Science.gov (United States)

    de Abreu, Daniela Cristina Carvalho; Takara, Kelly; Metring, Nathalia Lopes; Reis, Julia Guimaraes; Cliquet, Alberto, Jr.

    2012-01-01

    We aimed to evaluate the influence of different types of wheelchair seats on paraplegic individuals' postural control using a maximum anterior reaching test. Balance evaluations during 50, 75, and 90% of each individual's maximum reach in the forward direction using two different cushions on seat (one foam and one gel) and a no-cushion condition…

  4. Plyometric type neuromuscular exercise is a treatment to postural control deficits of volleyball players: A case study

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    A. Asadi

    2016-06-01

    Conclusions: It can be recommend that strength and conditioning professionals in the field of volleyball do not perform other type of landing exercise in plyometric training sessions because of postural control impaired and consequently the probability of lower extremity injuries will increase.

  5. To freeze or not to freeze? Affective and cognitive perturbations have markedly different effects on postural control

    NARCIS (Netherlands)

    Stins, J.F.; Roerdink, M.; Beek, P.J.

    2011-01-01

    Similar effects have been reported for diverting attention from postural control and increased anxiety on the characteristics of center-of-pressure (COP) time series (decreased excursions and elevated mean power frequency). These effects have also received similar interpretations in terms of

  6. Short-term effects of whole-body vibration on postural control in unilateral chronic stroke patients: preliminary evidence.

    NARCIS (Netherlands)

    Nes, I.J.W. van; Geurts, A.C.H.; Hendricks, H.T.; Duysens, J.E.J.

    2004-01-01

    The short-term effects of whole-body vibration as a novel method of somatosensory stimulation on postural control were investigated in 23 chronic stroke patients. While standing on a commercial platform, patients received 30-Hz oscillations at 3 mm of amplitude in the frontal plane. Balance was

  7. TENS to the Lateral Aspect of the Knees During Stance Attenuates Postural Sway in Young Adults

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    Yocheved Laufer

    2007-01-01

    Full Text Available Somatosensory input is known to be essential for postural control. The present study examined the effects on postural sway of sensory input delivered via transcutaneous electrical nerve stimulation (TENS applied to the knees during stance. Electrodes from a dual-channel portable TENS unit were adhered to the skin overlying the lateral and medial aspect of both knees of 20 young healthy volunteers (mean age 24.0 years, standard deviation 4.0. Postural sway parameters were obtained during static bipedal stance with an AMTI force platform. Four stimulation conditions were tested with eyes open and with eyes closed: no TENS; TENS applied bilaterally; and TENS applied to either the right or the left knee. Participants underwent two eight-trial blocks, with each trial lasting 30 seconds. The order of conditions was randomized for each participant. Stimulation consisted of a biphasic symmetrical stimulus delivered at the sensory detection level, with a pulse duration of 200μsec and a pulse frequency of 100Hz. The application of TENS induced significant reductions in mean sway velocity and in the medio-lateral dispersion of the center of pressure, with no corresponding effect on the anterior-posterior dispersion. These findings suggest that electrical stimulation delivered at the sensory detection level to the lateral aspects of the knees may be effective in improving balance control, and that this effect may be directionally specific.

  8. Design and validation of a morphing myoelectric hand posture controller based on principal component analysis of human grasping.

    Science.gov (United States)

    Segil, Jacob L; Weir, Richard F ff

    2014-03-01

    An ideal myoelectric prosthetic hand should have the ability to continuously morph between any posture like an anatomical hand. This paper describes the design and validation of a morphing myoelectric hand controller based on principal component analysis of human grasping. The controller commands continuously morphing hand postures including functional grasps using between two and four surface electromyography (EMG) electrodes pairs. Four unique maps were developed to transform the EMG control signals in the principal component domain. A preliminary validation experiment was performed by 10 nonamputee subjects to determine the map with highest performance. The subjects used the myoelectric controller to morph a virtual hand between functional grasps in a series of randomized trials. The number of joints controlled accurately was evaluated to characterize the performance of each map. Additional metrics were studied including completion rate, time to completion, and path efficiency. The highest performing map controlled over 13 out of 15 joints accurately.

  9. Perceptive rehabilitation and trunk posture alignment in patients with Parkinson disease: a single blind randomized controlled trial.

    Science.gov (United States)

    Morrone, Michelangelo; Miccinilli, Sandra; Bravi, Marco; Paolucci, Teresa; Melgari, Jean M; Salomone, Gaetano; Picelli, Alessandro; Spadini, Ennio; Ranavolo, Alberto; Saraceni, Vincenzo M; DI Lazzaro, Vincenzo; Sterzi, Silvia

    2016-12-01

    Recent studies aimed to evaluate the potential effects of perceptive rehabilitation in Parkinson Disease reporting promising preliminary results for postural balance and pain symptoms. To date, no randomized controlled trial was carried out to compare the effects of perceptive rehabilitation and conventional treatment in patients with Parkinson Disease. To evaluate whether a perceptive rehabilitation treatment could be more effective than a conventional physical therapy program in improving postural control and gait pattern in patients with Parkinson Disease. Single blind, randomized controlled trial. Department of Physical and Rehabilitation Medicine of a University Hospital. Twenty outpatients affected by idiopathic Parkinson Disease at Hoehn and Yahr stage ≤3. Recruited patients were divided into two groups: the first one underwent individual treatment with Surfaces for Perceptive Rehabilitation (Su-Per), consisting of rigid wood surfaces supporting deformable latex cones of various dimensions, and the second one received conventional group physical therapy treatment. Each patient underwent a training program consisting of ten, 45-minute sessions, three days a week for 4 consecutive weeks. Each subject was evaluated before treatment, immediately after treatment and at one month of follow-up, by an optoelectronic stereophotogrammetric system for gait and posture analysis, and by a computerized platform for stabilometric assessment. Kyphosis angle decreased after ten sessions of perceptive rehabilitation, thus showing a substantial difference with respect to the control group. No significant differences were found as for gait parameters (cadence, gait speed and stride length) within Su-Per group and between groups. Parameters of static and dynamic evaluation on stabilometric platform failed to demonstrate any statistically relevant difference both within-groups and between-groups. Perceptive training may help patients affected by Parkinson Disease into restoring

  10. Foot posture in female patients 5 years after breast-conserving surgery: a case-control study.

    Science.gov (United States)

    Głowacka-Mrotek, Iwona; Sowa, Magdalena; Nowikiewicz, Tomasz; Siedlecki, Zygmunt; Hagner, Wojciech; Zegarski, Wojciech

    2018-01-24

    Along with the improvement in the outcomes of breast cancer treatment being observed in the recent years, long-term studies to assess distant adverse effects of the treatment have become increasingly important. The objective of this study was to assess the foot posture in patients subjected to breast-conserving therapy. The assessment was made 5 years after the surgical procedure. 116 female patients (mean age of 58.75 years) were qualified into a case-control study. Foot posture on the operated breast side (F1) as well as on the contralateral side (F2) was evaluated using a computer-based foot analysis tool as an extension of projection moiré-based podoscopic examination. Comparisons were made for the following parameters: limb load, L-foot length, W-foot width, L/W-Wejsflog index, ALPHA-hallux valgus angle, BETA-little toe varus angle, GAMMA-heel angle, KY-Sztriter-Godunov index, CL-Clarke's angle, HW-heel width. Five years after BCT, patients placed higher load on the foot on the side of the healthy breast (p = 0.0011). No statistically significant differences were observed between F1 and F2 with respect to other foot posture parameters (p > 0.05). No statistically significant differences were observed in foot posture parameters in patients having undergone BCT + ALND (axillary lymph node dissection) procedure as compared to patients subjected to BCT + SLNB (sentinel lymph node biopsy) procedure (p > 0.05). No changes in foot posture were observed in patients 5 years after the BCT procedure. The type of the surgical procedure related to the lymph nodes within the axillary fossa has no effect on changes in foot posture.

  11. The effects of foot morphology and anthropometry on unipodal postural control

    Directory of Open Access Journals (Sweden)

    Angelica C. Alonso

    2016-03-01

    Full Text Available Abstract The maintenance of posture is a constant challenge for the body, as it requires rapid and accurate responses to unforeseen disturbances, which are needed to prevent falls and maintain balance. The purpose of the present study was to compare different types of plantar arch in relation to postural balance, and analyze the relationships between variations the plantar arch and anthropometric characteristics of the feet with unipedal static balance. We evaluated 100 men and women between the ages of 20 and 40 years old, to determine anthropometry and posturography with a force platform. There was a weak correlation between plantar arches and anthropometric measurements and postural balance, except for the length of the male foot, which showed a correlation between increased size and poorer static balance. We conclude that the type of plantar arch does not influence postural balance, and of the anthropometric factors, only foot length was related to postural balance.

  12. H-index is important for postural control for people with impaired foot sole sensation.

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    Shuqi Zhang

    Full Text Available People with Peripheral Neuropathy (PN, especially those with impaired sensory inputs through the small-afferent fiber (type II afferent fibers reflex loop (SAF, might depend more on the large-afferent fiber (type I afferent fibers reflex loop (LAF for postural control.To examine whether the function of the LAF reflex loop, reflected by the H-reflex and ankle joint proprioception, influences postural control when the SAF reflex loop is impaired, as indicated by reduced foot sole cutaneous sensation.Thirteen participants (8 women, 5 men diagnosed with PN and 12 age-matched controls (7 women, 5 men completed the testing protocol. Measures of interest included the H-index, active (AAP and passive (PAP ankle proprioception, plantar pressure sensitivity (PPS, average sway velocity (VAVG and area (A95 during 30 seconds eyes-closed standing, 6-minute walk distance (6MWD and timed up-and-go duration (TUG.Statistically significant group-dependent regression was observed between VAVG and H-index. Compared to the control group, the PN group demonstrated reduced PPS (2.0 ± 1.9 vs. 4.2 ± 1.2, P < .05 and H-index (63.6 ± 10.9 vs. 76.4 ± 16.0, P < .05, greater VAVG (3.5 ± 2.1 vs. 1.6 ± 0.6 cm/s, P < .05 and A95 (10.0 ± 10.1 vs. 2.5 ± 1.5 cm2, P < .05, shorter 6MWD (442.2 ± 93.0 vs. 525.3 ± 68.2 m, P < .05, and longer TUG (9.4 ± 1.6 vs. 6.5 ± 1.3 s, P < .05. Within the PN group, but not the control group, the H-index was correlated with VAVG (r = -.56, P < .05. Moreover, within the PN group only, PAP scores were correlated with 6MWD (r = -.68, P < .05 and TUG (r = -.59, P < .05 performance. No other statistically significant group difference, correlation or group-dependent regression was observed.VAVG, 6MWD, and TUG correlated with LAF reflex loop function observed among those with impaired functioning of the SAF reflex loop. This observation suggests that the LAF reflex loop may be critical to the control of balance in those individuals suffering

  13. Effects of Ankle Kinesio Taping on Postural Control in Stroke Patients.

    Science.gov (United States)

    Rojhani-Shirazi, Zahra; Amirian, Shiva; Meftahi, Narges

    2015-11-01

    To investigate the effects of kinesio taping on postural control in stroke patients. Forty stroke patients aged 30 to 60 years were randomly divided into an experimental and a control group. In the experimental group, kinesio tape (KT) was applied directly on the skin over the affected ankle in the direction of dorsiflexion and eversion to correct the equinovarus deformity. The tape was kept on the ankle for 1 day. The results were measured with the forward reach test, lateral reach test, Berg Balance Scale (BBS), and timed up and go test. Center of pressure (COP) displacement and velocity were also measured while the patients stood on a force plate. All variables were measured on the first day immediately after taping and 24 hours later in the KT group, and on the first day and also 24 hours later in the control group. There was a statistically significant difference in BBS between the first day and 24 hours later in the KT group (P = .01). The forward reach test and mediolateral displacement of the COP differed significantly after taping in the experimental group compared to the control group (P = .04). Immediately after taping, BBS improved significantly in the KT group (P = .02). The application of KT improved forward reach test results and displacement of the COP in stroke patients. Copyright © 2015 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  14. Determinants of sport-specific postural control strategy and balance performance of amateur rugby players.

    Science.gov (United States)

    Chow, Gary C C; Fong, Shirley S M; Chung, Joanne W Y; Chung, Louisa M Y; Ma, Ada W W; Macfarlane, Duncan J

    2016-11-01

    Postural control strategy and balance performance of rugby players are important yet under-examined issues. This study aimed to examine the differences in balance strategy and balance performance between amateur rugby players and non-players, and to explore training- and injury-related factors that may affect rugby players' balance outcomes. Cross-sectional and exploratory study. Forty-five amateur rugby players and 41 healthy active individuals participated in the study. Balance performance and balance strategies were assessed using the sensory organization test (SOT) of the Smart Equitest computerized dynamic posturography machine. Rugby training history and injury history were solicited from the participants. The SOT strategy scores were 1.99-54.90% lower in the rugby group than in the control group (prugby group than in the control group (prugby training (in years) was independently associated with the SOT condition 6 strategy score, explaining 15.7% of its variance (p=0.006). There was no association between SOT condition 6 strategy/equilibrium scores and injury history among the rugby players (p>0.05). Amateur rugby players demonstrated inferior balance strategy and balance performance compared to their non-training counterparts. Their suboptimal balance strategy was associated with insufficient training experience but not with history of injury. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  15. Global Postural Reeducation for patients with musculoskeletal conditions: a systematic review of randomized controlled trials

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    Giovanni E. Ferreira

    2016-01-01

    Full Text Available ABSTRACT Objectives To systematically review randomized controlled trials that assessed the effects of Global Postural Reeducation (GPR on patient-reported outcomes in conditions of the musculoskeletal system. Method An electronic search of MEDLINE (via PubMed, EMBASE, Cochrane CENTRAL, and SciELO was performed from their inception to June 2015. Randomized controlled trials that analyzed pain and patient-reported outcomes were included in this review. The Cochrane Collaboration’s Risk of Bias Tool was used to evaluate risk of bias, and the quality of evidence was rated following the GRADE approach. There were no language restrictions. Results Eleven trials were included totaling 383 patients. Overall, the trials had high risk of bias. GPR was superior to no treatment but not to other forms of treatment for pain and disability. No placebo-controlled trials were found. Conclusion GPR is not superior to other treatments; however, it is superior to no treatment. Due to the lack of studies, it is unknown if GPR is better than placebo. The quality of the available evidence ranges from low to very low, therefore future studies may change the effect estimates of GPR in musculoskeletal conditions.

  16. Global Postural Reeducation for patients with musculoskeletal conditions: a systematic review of randomized controlled trials

    Science.gov (United States)

    Ferreira, Giovanni E.; Barreto, Rodrigo G. P.; Robinson, Caroline C.; Plentz, Rodrigo D. M.; Silva, Marcelo F.

    2016-01-01

    ABSTRACT Objectives To systematically review randomized controlled trials that assessed the effects of Global Postural Reeducation (GPR) on patient-reported outcomes in conditions of the musculoskeletal system. Method An electronic search of MEDLINE (via PubMed), EMBASE, Cochrane CENTRAL, and SciELO was performed from their inception to June 2015. Randomized controlled trials that analyzed pain and patient-reported outcomes were included in this review. The Cochrane Collaboration’s Risk of Bias Tool was used to evaluate risk of bias, and the quality of evidence was rated following the GRADE approach. There were no language restrictions. Results Eleven trials were included totaling 383 patients. Overall, the trials had high risk of bias. GPR was superior to no treatment but not to other forms of treatment for pain and disability. No placebo-controlled trials were found. Conclusion GPR is not superior to other treatments; however, it is superior to no treatment. Due to the lack of studies, it is unknown if GPR is better than placebo. The quality of the available evidence ranges from low to very low, therefore future studies may change the effect estimates of GPR in musculoskeletal conditions. PMID:27437710

  17. Global Postural Reeducation for patients with musculoskeletal conditions: a systematic review of randomized controlled trials.

    Science.gov (United States)

    Ferreira, Giovanni E; Barreto, Rodrigo G P; Robinson, Caroline C; Plentz, Rodrigo D M; Silva, Marcelo F

    2016-04-01

    To systematically review randomized controlled trials that assessed the effects of Global Postural Reeducation (GPR) on patient-reported outcomes in conditions of the musculoskeletal system. An electronic search of MEDLINE (via PubMed), EMBASE, Cochrane CENTRAL, and SciELO was performed from their inception to June 2015. Randomized controlled trials that analyzed pain and patient-reported outcomes were included in this review. The Cochrane Collaboration's Risk of Bias Tool was used to evaluate risk of bias, and the quality of evidence was rated following the GRADE approach. There were no language restrictions. Eleven trials were included totaling 383 patients. Overall, the trials had high risk of bias. GPR was superior to no treatment but not to other forms of treatment for pain and disability. No placebo-controlled trials were found. GPR is not superior to other treatments; however, it is superior to no treatment. Due to the lack of studies, it is unknown if GPR is better than placebo. The quality of the available evidence ranges from low to very low, therefore future studies may change the effect estimates of GPR in musculoskeletal conditions.

  18. Clinical usefulness of the virtual reality-based postural control training on the gait ability in patients with stroke.

    Science.gov (United States)

    Park, Yu-Hyung; Lee, Chi-Ho; Lee, Byoung-Hee

    2013-01-01

    This study is a single blind randomized controlled trial to determine the effect of virtual reality-based postural control training on the gait ability in patients with chronic stroke. Sixteen subjects were randomly assigned to either experimental group (VR, n= 8) or control group (CPT, n= 8). Subjects in both groups received conventional physical therapy for 60 min per day, five days per week during a period of four weeks. Subjects in the VR group received additional augmented reality-based training for 30 min per day, three days per week during a period of four weeks. The subjects were evaluated one week before and after participating in a four week training and follow-up at one month post-training. Data derived from the gait analyses included spatiotemporal gait parameters, 10 meters walking test (10 mWT). In the gait parameters, subjects in the VR group showed significant improvement, except for cadence at post-training and follow-up within the experimental group. However, no obvious significant improvement was observed within the control group. In between group comparisons, the experimental group (VR group) showed significantly greater improvement only in stride length compared with the control group (Pgait parameters. In conclusion, we demonstrate significant improvement in gait ability in chronic stroke patients who received virtual reality based postural control training. These findings suggest that virtual reality (VR) postural control training using real-time information may be a useful approach for enhancement of gait ability in patients with chronic stroke.

  19. Variations in foot posture and mobility between individuals with patellofemoral pain and those in a control group.

    Science.gov (United States)

    McPoil, Thomas G; Warren, Meghan; Vicenzino, Bill; Cornwall, Mark W

    2011-01-01

    We sought to determine whether foot posture and foot mobility were increased in individuals with patellofemoral pain syndrome compared with individuals in a control group. A nested case-control design was used with two controls matched to each patient by sex and age (±1 year). Participants included 43 individuals with a history of unilateral or bilateral patellofemoral pain syndrome and 86 participants in a control group. Data collected included height, weight, and five different measures of foot height and width in weightbearing and nonweightbearing that have been previously shown to have high levels of reliability. Individuals with patellofemoral pain syndrome were found to be four times more likely (odds ratio, 4.04; 95% confidence interval, 1.45-11.32) to have a larger-than-normal difference between nonweightbearing and weightbearing arch height compared with those in the control group. The mean values for difference in arch height and foot mobility magnitude were also statistically significant between the patient and control groups. Foot posture, as determined using the arch height ratio, was not significant between groups (odds ratio, 0.94; 95% confidence interval, 0.34-2.61). Although foot posture may not be different between individuals with patellofemoral pain syndrome and controls, foot mobility assessed using difference in arch height and foot mobility magnitude is different between the two groups.

  20. Clinical usefulness of the virtual reality-based postural control training on the gait ability in patients with stroke

    Science.gov (United States)

    Park, Yu-Hyung; Lee, Chi-ho; Lee, Byoung-Hee

    2013-01-01

    This study is a single blind randomized controlled trial to determine the effect of virtual reality-based postural control training on the gait ability in patients with chronic stroke. Sixteen subjects were randomly assigned to either experimental group (VR, n= 8) or control group (CPT, n= 8). Subjects in both groups received conventional physical therapy for 60 min per day, five days per week during a period of four weeks. Subjects in the VR group received additional augmented reality-based training for 30 min per day, three days per week during a period of four weeks. The subjects were evaluated one week before and after participating in a four week training and follow-up at one month post-training. Data derived from the gait analyses included spatiotemporal gait parameters, 10 meters walking test (10 mWT). In the gait parameters, subjects in the VR group showed significant improvement, except for cadence at post-training and follow-up within the experimental group. However, no obvious significant improvement was observed within the control group. In between group comparisons, the experimental group (VR group) showed significantly greater improvement only in stride length compared with the control group (Pvirtual reality based postural control training. These findings suggest that virtual reality (VR) postural control training using real-time information may be a useful approach for enhancement of gait ability in patients with chronic stroke. PMID:24282810

  1. Influence of virtual reality on postural balance and quality of life of pregnant women: controlled clinical trial randomized

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    Silvia Oliveira Ribeiro

    Full Text Available Abstract Introduction: During pregnancy women undergo several transformations, which promote changes in their gravity center (GC and can result in postural and balance changes. Objective: To evaluate the influence of Nintendo WiiFit Plus® on postural balance and quality of life of pregnant women in the third trimester. Methods: 250 pregnant women enrolled through a non-probabilistic sampling process. The sample consisted of 32 women selected according to the eligibility criteria (nulliparity; low-risk pregnancy, absence of musculoskeletal disorders or surgical procedures in the spine, pelvis, hip or knee, musculoskeletal disorders, allocated as follows: 17 pregnant women in the control group (CG and 15 pregnant women in the experimental group (EG. The intervention was performed in 12 sessions of 30 minutes each, three times a week. Sociodemographic and obstetric data were presented as median and interquartile range (25% - 75%. A comparison of the relative values of variables before and after the exercise program was performed using the 2x2 ANOVA test (5% significance level. Results: There were no significant statistical differences in variables related to postural balance (P > 0.06 and quality of life (P > 0.13. Conclusion: The use of Nintendo WiiFit Plus games was not able to promote improvement in postural balance and quality of life of the pregnant women studied.

  2. Anodal Transcranial Direct Current Stimulation Shows Minimal, Measure-Specific Effects on Dynamic Postural Control in Young and Older Adults: A Double Blind, Sham-Controlled Study.

    Science.gov (United States)

    Craig, Chesney E; Doumas, Michail

    2017-01-01

    We investigated whether stimulating the cerebellum and primary motor cortex (M1) using transcranial direct current stimulation (tDCS) could affect postural control in young and older adults. tDCS was employed using a double-blind, sham-controlled design, in which young (aged 18-35) and older adults (aged 65+) were assessed over three sessions, one for each stimulatory condition-M1, cerebellar and sham. The effect of tDCS on postural control was assessed using a sway-referencing paradigm, which induced platform rotations in proportion to the participant's body sway, thus assessing sensory reweighting processes. Task difficulty was manipulated so that young adults experienced a support surface that was twice as compliant as that of older adults, in order to minimise baseline age differences in postural sway. Effects of tDCS on postural control were assessed during, immediately after and 30 minutes after tDCS. Additionally, the effect of tDCS on corticospinal excitability was measured by evaluating motor evoked potentials using transcranial magnetic stimulation immediately after and 30 minutes after tDCS. Minimal effects of tDCS on postural control were found in the eyes open condition only, and this was dependent on the measure assessed and age group. For young adults, stimulation had only offline effects, as cerebellar stimulation showed higher mean power frequency (MPF) of sway 30 minutes after stimulation. For older adults, both stimulation conditions delayed the increase in sway amplitude witnessed between blocks one and two until stimulation was no longer active. In conclusion, despite tDCS' growing popularity, we would caution researchers to consider carefully the type of measures assessed and the groups targeted in tDCS studies of postural control.

  3. The Effect of Rope Jumping Exercise on Postural Control, Static and Dynamic Balance in Male Students with Cavus Foot

    Directory of Open Access Journals (Sweden)

    Mahdi Ghaderiyan

    2016-06-01

    Full Text Available Background and Objectives: Plantar foot is a very active part in leap activities, such as rope jumping and with its small surface playes an important role in balance control. In this research, the effect of 12 week rope jumping exercise was investigated on postural control and static and dynamic balance in 10-13 years old male students with cavus foot. Methods: This quasi-experimental study was done on 450 male students aged 13-10 years in Jarghouyeh sofla. After the initial evaluation by pedescope (qualitative and then measurement by a foot scanner (quantitative and Staheli index, 30 students were selected as samples and were divided into two groups (experimental and control, each 15 cases. To measure the postural control, a foot scanner device was used and changes in plantar center of pressure was recorded for 20 seconds. Static balance was evaluated with stork test and dynamic balance by Y balance test. The subjects of the experimental group participated in a rope jumping training protocol three 45-minute sessions per week for 12 weeks. In this period of time, the subjects of the control group did not participate in any regular physical activity program in this time. Data were analyzed using dependent and independent t-tests. The significance level was considered p<0/05. Results: A 12-week rope jumping exercise improved postural control and static and dynamic balance in patients with cavus foot, which this change was significant (p<0.001. Conclusion: According to the results of this study, rope jumping can be a useful exercise to improve static and dynamic balance and postural control in individuals with cavus foot.

  4. [Evaluation of postural control systems in elderly patients with repeated falls].

    Science.gov (United States)

    González Ramírez, Alfonso; Lázaro del Nogal, Montserrat; Ribera Casado, José Manuel

    2008-01-01

    a) to describe postural control disorders in elderly patients with recurrent falls; b) to analyze the influence of sensory deficits on centre of gravity control mechanisms; and c) to assess the functional consequences of balance disorders and falls in this group of patients. patients aged more than 65 years old referred to a falls unit with two or more falls in the previous 6 months were included in this study. The protocol included posturographic studies with a Neurocom Balance Master. To evaluate motor control, Rhythmic Weight Shift (RWS test) was performed. To assess sensorial control, Modified Clinical Test of Sensory Interaction on Balance (MCT test) was used. Other tests performed were the Sit to Stand (SS test), Walk across (WA test) and Step up over (SO test). a total of 109 patients (85.3% women) were studied. Mean age was 78.01 years (SD: 5.38). Disorders in one or more afferent sensorial systems were found in 51.7% of the patients (27.5% visual deficiencies, 17.6% vestibular alterations, and 6.6% somatosensorial deficits). Two afferent systems were compromised in 25.3%, and all three were compromised in 11.1% of the patients. No significant differences were found in directional control (RWS) when compared with the number of altered systems. posturographic studies provide sensitive information on static and dynamic centre of gravity control systems, eventual sensory deficits, and patients' ability to carry out basic activities of daily living. In our sample, the most frequent deficit was visual impairment. This information is essential to establish a correct management programme.

  5. Postural control in patients after a recent vestibular neuritis with hyperhomocysteinemia.

    Science.gov (United States)

    Raponi, G; Teggi, R; Gatti, O; Giordano, L; Bussi, M

    2013-04-01

    To assess the possible role of hyperhomocysteinemia (HyHcy) in delaying recovery after acute vestibular neuritis. In our retrospective study, 90 subjects were evaluated within 7 days from the beginning of an acute vertigo. All subjects had high plasma levels of homocysteine (Hcy). 46 patients were treated with homocysteine lowering therapy and betahistine for 1 month, while 44 subjects received only betahistine. Subjective symptoms were evaluated with the Dizziness Handicap Inventory (DHI) questionnaire, administered 7 days after the beginning of vertigo and again after 1 month. Moreover, postural control performed at 1 month' control was studied with static stabilometry in a subgroup of 21 non-treated and 20 treated patients. DHI total score decreased significantly more in the subgroup of subjects treated with homocysteine lowering therapy. Moreover, posturographic data were significantly increased in non-treated compared with treated subjects. Our data support the possibility of a role of HyHcy in preventing recovery after a recent vestibular neuritis. A microvascular disorder or the neurotoxic effect of HyHcy have been considered as possible causal factors. Although not conclusive, our data are not inconsistent with the hypothesis of a poorer adaptation in patients with untreated HyHcy.

  6. Assessment of the postural control strategies used to play two Wii Fit™ videogames.

    Science.gov (United States)

    Michalski, A; Glazebrook, C M; Martin, A J; Wong, W W N; Kim, A J W; Moody, K D; Salbach, N M; Steinnagel, B; Andrysek, J; Torres-Moreno, R; Zabjek, K F

    2012-07-01

    The Nintendo Wii Fit™ may provide an affordable alternative to traditional biofeedback or virtual reality systems for retraining or improving motor function in populations with impaired balance. The purpose of this study was to evaluate postural control strategies healthy individuals use to play Wii Fit™ videogames. Sixteen young adults played 10 trials of Ski Slalom and Soccer Heading respectively. Centre of pressure (COP) excursion and three-dimensional movement data were acquired to determine variability in medial-lateral COP sway and shoulder-pelvic movement. While there was no difference in medial-lateral COP variability between games during trial 1, there was a significant difference after 10 trials. COP sway increased (59-75 mm) for Soccer Heading while it decreased (67-33 mm) for Ski Slalom from trial 1 to trial 10. During Ski Slalom participants demonstrated decreased shoulder and pelvic movement combined with increased pelvic-shoulder coupling. Conversely, participants demonstrated greater initial shoulder tilt when playing Soccer Heading, with no reduction in pelvic rotation and tilt. Participants decreased pelvic and trunk movements when skiing, suggesting a greater contribution of lower extremity control while they primarily used a trunk strategy to play Soccer Heading. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. Alterations in postural control during the world's most challenging mountain ultra-marathon.

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    Francis Degache

    Full Text Available We investigated postural control (PC effects of a mountain ultra-marathon (MUM: a 330-km trail run with 24000 m of positive and negative change in elevation. PC was assessed prior to (PRE, during (MID and after (POST the MUM in experienced ultra-marathon runners (n = 18; finish time = 126 ± 16 h and in a control group (n = 8 with a similar level of sleep deprivation. Subjects were instructed to stand upright on a posturographic platform over a period of 51.2 seconds using a double-leg stance under two test conditions: eyes open (EO and eyes closed (EC. Traditional measures of postural stability (center of pressure trajectory analysis and stabilogram-diffusion analysis (SDA parameters were analysed. For the SDA, a significantly greater short-term effective diffusion was found at POST compared with PRE in the medio-lateral (ML; Dxs and antero-posterior (AP directions (Dys in runners (p<0.05 The critical time interval (Ctx in the ML direction was significantly higher at MID (p<0.001 and POST (p<0.05 than at PRE in runners. At MID (p<0.001 and POST (p<0.05, there was a significant difference between the two groups. The critical displacement (Cdx in the ML was significantly higher at MID and at POST (p<0.001 compared with PRE for runners. A significant difference in Cdx was observed between groups in EO at MID (p<0.05 and POST (p<0.005 in the ML direction and in EC at POST in the ML and AP directions (p<0.05. Our findings revealed significant effects of fatigue on PC in runners, including, a significant increase in Ctx (critical time in ML plan in EO and EC conditions. Thus, runners take longer to stabilise their body at POST than at MID. It is likely that the mountainous characteristics of MUM (unstable ground, primarily uphill/downhill running, and altitude increase this fatigue, leading to difficulty in maintaining balance.

  8. Does postural sway change in association with manual therapeutic interventions? A review of the literature

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    Ruhe Alexander

    2013-02-01

    Full Text Available Abstract Study design Literature Review Objectives The objective of this literature review was to determine if postural sway changes in association with manual therapeutic interventions and to investigate whether any changes occur in healthy individuals or in association with pain intensity. Summary of Background data Improving postural stability has been proposed as a goal of manual therapeutic interventions. So far, no literature review has addressed whether there is supportive evidence for this and if so, what factors may be associated or causative for observed sway alterations. Search methods Seven online databases (PubMed, MEDLINE, EMBASE, CINAHL, Web of Science, ScienceDirect and the Cochrane library were systematically searched followed by a manual search of the retrieved papers. Selection criteria Studies comparing postural sway derived from bipedal force plate measurements in association with a manual therapeutic intervention, ideally compared to a control group. Data collection and analysis Two reviewers independently screened titles and abstracts for relevance, conducted the data extraction and the risk of bias assessment which was conducted using the RTI item bank. A descriptive analysis was conducted as the heterogeneous study designs prevented pooling of data. Results Nine studies of varying methodological quality met the inclusion criteria. No direct comparison of data across the studies was possible. There was no evidence that manual interventions lead to a change in postural sway in healthy individuals regardless of the body regions addressed by the intervention. There was some indication that postural sway may change at follow-up measurements in pain sufferers; however, this may be due to variations in pain intensity rather than resulting from the intervention itself. Conclusions There is no conclusive scientific evidence that manual therapeutic interventions may exhibit any immediate or long-term effect on COP excursions. Any

  9. Equilíbrio, controle postural e força muscular em idosas osteoporóticas com e sem quedas Balance, postural control and muscle strength in osteoporotic elderly women with and without falls

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    Sarah Rubia Ferreira de Meneses

    2012-03-01

    Full Text Available Um dos maiores problemas de saúde pública na população idosa são as quedas, agravando-se quando relacionadas à presença de osteoporose. Dentre os vários fatores de risco, destacam-se a diminuição do equilíbrio, controle postural e força muscular. O objetivo deste trabalho foi comparar o equilíbrio, o controle postural e a força muscular em idosas osteoporóticas com e sem quedas referidas no último ano. Foram avaliadas 45 mulheres entre 65 e 85 anos, divididas em dois grupos com base no relato de quedas nos 12 meses anteriores à avaliação: grupo com quedas (GCQ; n=21 e grupo sem quedas (GSQ; n=24. O equilíbrio foi avaliado por meio da escala de equilíbrio de Berg; o controle postural pelo teste clínico modificado de interação sensorial no equilíbrio (mCTSIB, realizado no equipamento Balance Master®; e a força muscular dos flexores e extensores de joelho e dorsiflexores de tornozelo, com dinamômetro EMG System do Brasil®. Foi considerado nível de significância α=0,05. Houve diferença significativa no equilíbrio (p0,05. Nossos resultados indicam que idosas osteoporóticas com histórico de quedas nos últimos 12 meses possuem pior equilíbrio e controle postural em relação às osteoporóticas sem quedas referidas.Falls are one of the biggest public health problems in the elderly population, worsening when related to the presence of osteoporosis. Among the various risk factors are highlighted decreased balance, muscle strength and postural control. This study aim is to compare the balance, postural control and muscle strength in osteoporotic elderly women with and without falls reported in the last year. We evaluated 45 women between 65 and 85 years, divided into two groups, based on reports of falls in the 12 months prior to assessment: group with falls (n=21 and group without falls (n=24. Balance was assessed using the Berg balance scale; postural control by the modified clinical test of sensory interaction on

  10. Unexpected terrestrial hand posture diversity in wild mountain gorillas.

    Science.gov (United States)

    Thompson, Nathan E; Ostrofsky, Kelly R; McFarlin, Shannon C; Robbins, Martha M; Stoinski, Tara S; Almécija, Sergio

    2018-01-18

    Gorillas, along with chimpanzees and bonobos, are ubiquitously described as 'knuckle-walkers.' Consequently, knuckle-walking (KW) has been featured pre-eminently in hypotheses of the pre-bipedal locomotor behavior of hominins and in the evolution of locomotor behavior in apes. However, anecdotal and behavioral accounts suggest that mountain gorillas may utilize a more complex repertoire of hand postures, which could alter current interpretations of African ape locomotion and its role in the emergence of human bipedalism. Here we documented hand postures during terrestrial locomotion in wild mountain gorillas to investigate the frequency with which KW and other hand postures are utilized in the wild. Multiple high-speed cameras were used to record bouts of terrestrial locomotion of 77 habituated mountain gorillas at Bwindi Impenetrable National Park (Uganda) and Volcanoes National Park (Rwanda). We captured high-speed video of hand contacts in 8% of the world's population of mountain gorillas. Our results reveal that nearly 40% of these gorillas used "non-KW" hand postures, and these hand postures constituted 15% of all hand contacts. Some of these "non-KW" hand postures have never been documented in gorillas, yet match hand postures previously identified in orangutans. These results highlight a previously unrecognized level of hand postural diversity in gorillas, and perhaps great apes generally. Although present at lower frequencies than KW, we suggest that the possession of multiple, versatile hand postures present in wild mountain gorillas may represent a shared feature of the African ape and human clade (or even great ape clade) rather than KW per se. © 2018 Wiley Periodicals, Inc.

  11. 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.

  12. Postural Control in Workplace Safety: Role of Occupational Footwear and Workload

    Directory of Open Access Journals (Sweden)

    Harish Chander

    2017-08-01

    Full Text Available Maintaining postural stability is crucial, especially in hazardous occupational environments. The purpose of the study was to assess the role of three occupational footwear (low top shoe (LT; tactical work boot (TB and steel-toed work boot (WB on postural stability when exposed to an occupational workload (4-h involving standing/walking using the sensory organization test (SOT equilibrium (EQ scores and comparing current results with previously published postural sway variables from the same study. Fourteen male adults were tested on three separate days wearing a randomized occupational footwear, at the beginning (pre and every 30 min of the 4-h workload until 240th min. SOT EQ scores were analyzed using a 3 × 9 repeated measures analysis of variance at an alpha level of 0.05. Significant differences between footwear was found in eyes open (p = 0.03 and eyes closed (p = 0.001 conditions. Pairwise comparisons revealed that LT had significantly lower postural stability compared to TB and WB. No other significant differences were found between footwear and over time. Significant differences between footwear can be attributed to design characteristics of footwear. Lack of significant differences over time suggests that, even though the average EQ scores decreased during the workload implying less postural stability, SOT EQ scores alone may not be sufficient to detect postural stability changes over the 4-h workload.

  13. The effects of kinesio taping on potential in chronic low back pain patients anticipatory postural control and cerebral cortex.

    Science.gov (United States)

    Bae, Sea Hyun; Lee, Jeong Hun; Oh, Kyeong Ae; Kim, Kyung Yoon

    2013-11-01

    [Purpose] This study aimed to examine the effects of kinesio tape applied to chronic low back pain (CLBP) patients on anticipatory postural control and cerebral cortex potential. [Subjects and Methods] Twenty patients whose low back pain had continued for more than 12 weeks were selected and assigned to a control group (n=10) to which ordinary physical therapy was applied and an experimental group (n=10) to which kinesio tape was applied. Anticipatory postural control was evaluated using electromyography, and movement-related cortical potential (MRCP) was assessed using electroencephalography. Clinical evaluation was performed using a visual analogue scale and the Oswestry disability index. [Results] According to the analysis results for anticipatory postural control, there were significant decreases in the transversus abdominis (TrA) muscle and the external oblique muscle in both groups. Among them, the TrA of the experimental group exhibited the greatest differences. According to the results of a between-group comparison, there was significant difference in the TrA between the two groups. There was also a significant decrease in the MRCP of both groups. In particular, changes in the movement monitoring potential (MMP) of the experimental group were greatest at Fz, C3, Cz, and C4. According to the between-group comparison, there were significant differences in MMP at F3, C3, and Cz. Both groups saw VAS and ODI significantly decrease. Among them, the ODI of the experimental group underwent the greatest change. [Conclusion] Kinesio tape applied to CLBP patients reduced their pain and positively affected their anticipatory postural control and MRCP.

  14. Human Odometry Verifies the Symmetry Perspective on Bipedal Gaits

    Science.gov (United States)

    Turvey, M. T.; Harrison, Steven J.; Frank, Till D.; Carello, Claudia

    2012-01-01

    Bipedal gaits have been classified on the basis of the group symmetry of the minimal network of identical differential equations (alias "cells") required to model them. Primary gaits are characterized by dihedral symmetry, whereas secondary gaits are characterized by a lower, cyclic symmetry. This fact was used in a test of human…

  15. Simulating an elastic bipedal robot based on musculoskeletal modeling

    NARCIS (Netherlands)

    Bortoletto, Roberto; Sartori, Massimo; He, Fuben; Pagello, Enrico

    2012-01-01

    Many of the processes involved into the synthesis of human motion have much in common with problems found in robotics research. This paper describes the modeling and the simulation of a novel bipedal robot based on series elastic actuators [1]. The robot model takes in- spiration from the human

  16. Tractable Quantification of Metastability for Robust Bipedal Locomotion

    Science.gov (United States)

    2015-06-01

    Mathematics GPA 4.0/4.0 2007-2011 Sabanci University, Istanbul B.S. in Mechatronics Engineering Minor in Mathematics GPA 3.88/4.0 Major GPA: 3.96/4.00...on Mechatronics (ICM), pages 997-1002, April 2011. viii Abstract Tractable Quantification of Metastability for Robust Bipedal Locomotion by Cenk Oguz

  17. Differences in segmental coordination and postural control in a multi-joint dance movement: développé arabesque.

    Science.gov (United States)

    Bronner, Shaw

    2012-03-01

    Analysis of skill at multiple points on the learning continuum provides insight into how complex limb and postural organization is modified with extended practice. Dancers at three skill levels were compared performing a domain-specific movement (développé arabesque) to identify motor control parameters underlying skill acquisition of a sequential multi-joint trunk and extremity movement. It was hypothesized that general organization would be similar between groups, but that segmental coordination and postural control would differ with skill level. Twenty-seven expert, advanced, and intermediate dancers performed six repetitions of an arabesque sequence with the right limb. Data were acquired with a five-camera motion analysis system. Differences between groups in pelvis and gesture limb displacement, joint coordination patterns, and variability were determined using ANOVA with post hoc comparisons where applicable. Subjects displayed similar movement organization and timing. Differences were found in postural pelvic control and intra- and inter-limb coordination. These differences were most apparent during the arabesque phase. Control of the pelvis appears to be a key area that requires prolonged practice to master.

  18. Effect of vibration on postural control and gait of elderly subjects: a systematic review.

    Science.gov (United States)

    Aboutorabi, Atefeh; Arazpour, Mokhtar; Bahramizadeh, Mahmood; Farahmand, Farzam; Fadayevatan, Reza

    2017-09-16

    Gait and balance disorders are common in the elderly populations, and their prevalence increases with age. This systematic review was performed to summarize the current evidence for subthreshold vibration interventions on postural control and gait in elderly. A review of intervention studies including the following words in the title/abstract: insole, foot and ankle appliances, vibration, noise and elderly related to balance and gait. Databases searched included PubMed, ISI Web of Knowledge, Ovid, Scopus, and Google Scholar. Fifteen articles were selected for final evaluation. The procedure was followed using the preferred reporting items for systematic reviews and meta-analysis method. There was reduction in center of pressure velocity and displacement especially with eyes closed using vibration in healthy elderly subjects and this effect was greater in elderly faller and patients with more balance deficiency. Vibration programme training increased speed of walking, cadence, step time and length in stroke subjects. The vibratory insoles significantly improved performance on the Timed Up and Go and Functional Reach tests in older people. Vibration was effective on balance improvement in elderly subject especially elderly with more balance deficiency and it can improve gait parameters in patients with greater baseline variability.

  19. Mastoid vibration affects dynamic postural control during gait in healthy older adults

    Science.gov (United States)

    Chien, Jung Hung; Mukherjee, Mukul; Kent, Jenny; Stergiou, Nicholas

    2017-01-01

    Vestibular disorders are difficult to diagnose early due to the lack of a systematic assessment. Our previous work has developed a reliable experimental design and the result shows promising results that vestibular sensory input while walking could be affected through mastoid vibration (MV) and changes are in the direction of motion. In the present paper, we wanted to extend this work to older adults and investigate how manipulating sensory input through mastoid vibration (MV) could affect dynamic postural control during walking. Three levels of MV (none, unilateral, and bilateral) applied via vibrating elements placed on the mastoid processes were combined with the Locomotor Sensory Organization Test (LSOT) paradigm to challenge the visual and somatosensory systems. We hypothesized that the MV would affect sway variability during walking in older adults. Our results revealed that MV significantly not only increased the amount of sway variability but also decreased the temporal structure of sway variability only in anterior-posterior direction. Importantly, the bilateral MV stimulation generally produced larger effects than the unilateral. This is an important finding that confirmed our experimental design and the results produced could guide a more reliable screening of vestibular system deterioration.

  20. The Effects of Plyometric Type Neuromuscular Training on Postural Control Performance of Male Team Basketball Players.

    Science.gov (United States)

    Asadi, Abbas; Saez de Villarreal, Eduardo; Arazi, Hamid

    2015-07-01

    Anterior cruciate ligament injuries are common in basketball athletes; common preventive programs for decreasing these injures may be enhancing postural control (PC) or balance with plyometric training. This study investigated the efficiency of plyometric training program within basketball practice to improve PC performance in young basketball players. Sixteen players were recruited and assigned either to a plyometric + basketball training group (PT) or basketball training group (BT). All players trained twice per week, but the PT + BT followed a 6-week plyometric program implemented within basketball practice, whereas the BT followed regular practice. The star excursion balance test (SEBT) at 8 directions (anterior, A; anteromedial, AM; anterolateral, AL; medial, M; lateral, L; posterior, P; posteromedial, PM; and posterolateral, PL) was measured before and after the 6-week period. The PT group induced significant improvement (p ≤ 0.05) and small to moderate effect size in the SEBT (A = 0.95, AM = 0.62, AL = 0.61, M = 0.36, L = 0.47, P = 0.27, PM = 0.25, PL = 0.24). No significant improvements were found in the BT group. Also, there were significant differences between groups in all directions except PM and PL. An integrated plyometric program within the regular basketball practice can lead to significant improvements in SEBT and consequently PC. It can be recommended that strength and conditioning professionals use PT to enhance the athletes' joint awareness and PC to reduce possible future injuries in the lower extremity.

  1. Independent walking as a major skill for the development of anticipatory postural control: evidence from adjustments to predictable perturbations.

    Directory of Open Access Journals (Sweden)

    Fabien Cignetti

    Full Text Available Although there is suggestive evidence that a link exists between independent walking and the ability to establish anticipatory strategy to stabilize posture, the extent to which this skill facilitates the development of anticipatory postural control remains largely unknown. Here, we examined the role of independent walking on the infants' ability to anticipate predictable external perturbations. Non-walking infants, walking infants and adults were sitting on a platform that produced continuous rotation in the frontal plane. Surface electromyography (EMG of neck and lower back muscles and the positions of markers located on the platform, the upper body and the head were recorded. Results from cross-correlation analysis between rectified and filtered EMGs and platform movement indicated that although muscle activation already occurred before platform movement in non-walking infants, only walking infants demonstrated an adult-like ability for anticipation. Moreover, results from further cross-correlation analysis between segmental angular displacement and platform movement together with measures of balance control at the end-points of rotation of the platform evidenced two sorts of behaviour. The adults behaved as a non-rigid non-inverted pendulum, rather stabilizing head in space, while both the walking and non-walking infants followed the platform, behaving as a rigid inverted pendulum. These results suggest that the acquisition of independent walking plays a role in the development of anticipatory postural control, likely improving the internal model for the sensorimotor control of posture. However, despite such improvement, integrating the dynamics of an external object, here the platform, within the model to maintain balance still remains challenging in infants.

  2. Another look at the foramen magnum in bipedal mammals.

    Science.gov (United States)

    Russo, Gabrielle A; Kirk, E Christopher

    2017-04-01

    A more anteriorly positioned foramen magnum evolved in concert with bipedalism at least four times within Mammalia: once in macropodid marsupials, once in heteromyid rodents, once in dipodid rodents, and once in hominoid primates. Here, we expand upon previous research on the factors influencing mammalian foramen magnum position (FMP) and angle with four new analyses. First, we quantify FMP using a metric (basioccipital ratio) not previously examined in a broad comparative sample of mammals. Second, we evaluate the potential influence of relative brain size on both FMP and foramen magnum angle (FMA). Third, we assess FMP in an additional rodent clade (Anomaluroidea) containing bipedal springhares (Pedetes spp.) and gliding/quadrupedal anomalures (Anomalurus spp.). Fourth, we determine the relationship between measures of FMP and FMA in extant hominoids and an expanded mammalian sample. Our results indicate that bipedal/orthograde mammals have shorter basioccipitals than their quadrupedal/non-orthograde relatives. Brain size alone has no discernible effect on FMP or FMA. Brain size relative to palate size has a weak influence on FMP in some clades, but effects are not evident in all metrics of FMP and are inconsistent among clades. Among anomaluroids, bipedal Pedetes exhibits a more anterior FMP than gliding/quadrupedal Anomalurus. The relationship between FMA and FMP in hominoids depends on the metric chosen for quantifying FMP, and if modern humans are included in the sample. However, the relationship between FMA and FMP is nonexistent or weak across rodents, marsupials, and, to a lesser extent, strepsirrhine primates. These results provide further evidence that bipedal mammals tend to have more anteriorly positioned foramina magna than their quadrupedal close relatives. Our findings also suggest that the evolution of FMP and FMA in hominins may not be closely coupled. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Effects of long-term stimulation of textured insoles on postural control in health elderly.

    Science.gov (United States)

    Annino, Giuseppe; Palazzo, Francesco; Alwardat, Mohammad S; Manzi, Vincenzo; Lebone, Pietro; Tancredi, Virginia; Sinibaldi Salimei, Paola; Caronti, Alfio; Panzarino, Michele; Padua, Elvira

    2018-04-01

    The aim of this study was to confirm the effects of long term (chronic) stimulating surface (textured insole) on body balance of elderly people. Twenty-four healthy elderly individuals were randomly distributed in two groups: control and experimental (67.75±6.04 years, 74.55±12.14 kg, 163.7±8.55 cm, 27.75±3.04 kg/m2). Over one month, control group (CG) used smooth insoles and the experimental group (ExG) used textured insoles every day. Velocity net (Vnet), anteroposterior (VA/P), mediolateral (VM/L) and sway path of CoP were assessed in different eye conditions before and after the experimental procedure. A mixed between-within subject ANOVA was conducted to assess the impact of soft and textured insoles and two visual conditions (vision vs. no vision) across two time periods (α≤0.05). The results showed any statistical difference between groups in each parameter assessed in this study. CoP, Vnet and VM/L in the experimental group showed a statistically significant effect of textured insoles only without vision (CoP: P=0.002; η2=0.35), Vnet P=0.02; η2=0.24, VM/L P=0.04; η2=0.177) whereas VA/P showed no statistically significant effect in the same group and condition. There was no significant effect in Vnet, VA/P, VM/L and COP in control group that used smooth insole for both eye conditions. The results confirm that postural stability improved in healthy elderly individuals, increasing somatosensory information's from feet plantar mechanoreceptors. Long term stimulation with textured insoles decreased CoP, Vnet and VM/L with eyes closed.

  4. A Combination of Central Pattern Generator-based and Reflex-based Neural Networks for Dynamic, Adaptive, Robust Bipedal Locomotion

    DEFF Research Database (Denmark)

    Di Canio, Giuliano; Larsen, Jørgen Christian; Wörgötter, Florentin

    2016-01-01

    Robotic systems inspired from humans have always been lightening up the curiosity of engineers and scientists. Of many challenges, human locomotion is a very difficult one where a number of different systems needs to interact in order to generate a correct and balanced pattern. To simulate...... the interaction of these systems, implementations with reflexbased or central pattern generator (CPG)-based controllers have been tested on bipedal robot systems. In this paper we will combine the two controller types, into a controller that works with both reflex and CPG signals. We use a reflex-based neural...... network to generate basic walking patterns of a dynamic bipedal walking robot (DACBOT) and then a CPG-based neural network to ensure robust walking behavior...

  5. Effect of Prophylactic Ankle-Brace Use During a High School Competitive Basketball Season on Dynamic Postural Control.

    Science.gov (United States)

    Crockett, Nathan J; Sandrey, Michelle A

    2015-08-01

    Few studies have evaluated the long-term effects of prophylactic ankle-brace use during a sport season. To determine the effects of prophylactic ankle-brace use during a high school basketball season on dynamic postural control and functional tests. Prospective repeated-measures design. High school athletic facility. 21 healthy high school basketball athletes (13 girls, 8 boys). The order of testing was randomized using the Star Excursion Balance Test (SEBT) for posteromedial (PM), medial (M), and anteromedial (AM) directions and 3 functional tests (FT) consisting of the single-leg crossover hop, single-leg vertical jump, and the single-leg 6-m hop for time at pre-, mid-, and postseason. After pretesting, the ankle brace was worn on both limbs during the entire 16-wk competitive basketball season. SEBT for PM, M, and AM and 3 single-leg FTs. Dynamic postural control using the SEBT and the 3 FTs improved over time, notably from pretest to posttest. The left limb was different from the right limb during the single-leg vertical jump. Effect sizes were large for pretest to posttest for the 3 SEBT directions and 2 of the 3 FTs. The 16-wk basketball prophylactic ankle-brace intervention significantly improved dynamic postural control and single-limb FTs over time.

  6. The validity of a portable clinical force plate in assessment of static postural control: concurrent validity study.

    Science.gov (United States)

    Golriz, Samira; Hebert, Jeffrey J; Foreman, K Bo; Walker, Bruce F

    2012-05-23

    The broad use of force plates in clinical settings for postural control assessment suggests the need for instruments that are easy to use, affordable and readily available. In addition, these instruments of measurement should be reliable and valid as adequate reliability and validity are prerequisites to making correct inferences. The aim of this study was to examine the concurrent validity of postural control measures obtained with a clinical force plate. Thirty-one healthy adults were recruited. Participants completed 1 set of 5 trials on each force plate. Postural control measures (centre of pressure [COP] average velocity and sway area) were collected and compared using the Midot Posture Scale Analyzer (clinical force plate) and the Accugait force plate (criterion measure). Intra class correlation coefficient (ICC), standard error of measurement , and paired t-tests were calculated and Bland-Altman plots were constructed to compare the force plates and assess consistency of measurement and agreement between them. The ICC values (ICC = 0.14-0.60) between the two force plates were lower than the acceptable value for both COP average velocity and sway area. There was significant difference (p > 0.05) in COP average velocity and sway area between the force plates. Examination of the plots revealed that there is less difference between the force plates in lower magnitudes of COP for average velocity and sway area however, the greater the average velocity and sway area, the greater the difference between the measures obtained from the two force plates. Findings of this study showed poor concurrent validity of the clinical force plate. This clinical force plate cannot be a replacement for known reliable and valid force plates and consequently measures obtained from this force plate should be treated with caution especially in a clinical population.

  7. What is Bobath? A survey of UK stroke physiotherapists' perceptions of the content of the Bobath concept to treat postural control and mobility problems after stroke

    OpenAIRE

    Tyson, Sarah F.; Connell, L. A.; Busse, M. E.; Lennon, S.

    2009-01-01

    Objective. The aim of this study was to identify which interventions used to treat postural control and mobility are considered part of the Bobath concept (BC). Design. Hospital-based UK stroke physiotherapists identified interventions which they perceived to be part of the BC from a pre-published list of interventions used to treat postural control and mobility problems. Interventions that >75% of participants felt were part of the BC were classified as 'definitely Bobath'. Interventions ...

  8. Effects of different lower-limb sensory stimulation strategies on postural regulation-A systematic review and meta-analysis.

    Directory of Open Access Journals (Sweden)

    Mei Teng Woo

    Full Text Available Systematic reviews of balance control have tended to only focus on the effects of single lower-limb stimulation strategies, and a current limitation is the lack of comparison between different relevant stimulation strategies. The aim of this systematic review and meta-analysis was to examine evidence of effects of different lower-limb sensory stimulation strategies on postural regulation and stability. Moderate- to high- pooled effect sizes (Unbiased (Hedges' g standardized mean differences (SMD = 0.31-0.66 were observed with the addition of noise in a Stochastic Resonance Stimulation Strategy (SRSS, in three populations (i.e., healthy young adults, older adults, and individuals with lower-limb injuries, and under different task constraints (i.e., unipedal, bipedal, and eyes open. A Textured Material Stimulation Strategy (TMSS enhanced postural control in the most challenging condition-eyes-closed on a stable surface (SMD = 0.61, and in older adults (SMD = 0.30. The Wearable Garments Stimulation Strategy (WGSS showed no or adverse effects (SMD = -0.68-0.05 under all task constraints and in all populations, except in individuals with lower-limb injuries (SMD = 0.20. Results of our systematic review and meta-analysis revealed that future research could consider combining two or more stimulation strategies in intervention treatments for postural regulation and balance problems, depending on individual needs.

  9. Effects of different lower-limb sensory stimulation strategies on postural regulation-A systematic review and meta-analysis.

    Science.gov (United States)

    Woo, Mei Teng; Davids, Keith; Liukkonen, Jarmo; Orth, Dominic; Chow, Jia Yi; Jaakkola, Timo

    2017-01-01

    Systematic reviews of balance control have tended to only focus on the effects of single lower-limb stimulation strategies, and a current limitation is the lack of comparison between different relevant stimulation strategies. The aim of this systematic review and meta-analysis was to examine evidence of effects of different lower-limb sensory stimulation strategies on postural regulation and stability. Moderate- to high- pooled effect sizes (Unbiased (Hedges' g) standardized mean differences (SMD) = 0.31-0.66) were observed with the addition of noise in a Stochastic Resonance Stimulation Strategy (SRSS), in three populations (i.e., healthy young adults, older adults, and individuals with lower-limb injuries), and under different task constraints (i.e., unipedal, bipedal, and eyes open). A Textured Material Stimulation Strategy (TMSS) enhanced postural control in the most challenging condition-eyes-closed on a stable surface (SMD = 0.61), and in older adults (SMD = 0.30). The Wearable Garments Stimulation Strategy (WGSS) showed no or adverse effects (SMD = -0.68-0.05) under all task constraints and in all populations, except in individuals with lower-limb injuries (SMD = 0.20). Results of our systematic review and meta-analysis revealed that future research could consider combining two or more stimulation strategies in intervention treatments for postural regulation and balance problems, depending on individual needs.

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

    Directory of Open Access Journals (Sweden)

    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.

  11. Visual-vestibular control of posture and gait: physiological mechanisms and disorders.

    Science.gov (United States)

    Bronstein, A M; Guerraz, M

    1999-02-01

    The scientific analysis of clinical disorders of posture and gait is an emerging field. Precise definition of the forces and postural movements involved has been pivotal to understanding many aspects of the visual and vestibular contributions to balance. However, a great deal of argument still surrounds the question of how much gait and posture laboratories actually contribute to improve the clinical management of individual patients. One of the reasons why gait analysis techniques have not penetrated rehabilitation clinics may be that the research questions asked have been aimed at understanding mechanisms rather than at quantifying disability. The condition known as primary orthostatic tremor, which is not too well known to many neuro-otologists and posturographists, is briefly reviewed here. We propose that posturography could be the easiest way to diagnose this treatable condition.

  12. Effects of the anchor system on postural control in older Adults

    Directory of Open Access Journals (Sweden)

    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.

  13. The reliability of a portable clinical force plate used for the assessment of static postural control: repeated measures reliability study.

    Science.gov (United States)

    Golriz, Samira; Hebert, Jeffrey J; Foreman, K Bo; Walker, Bruce F

    2012-05-23

    Force plates are frequently used for postural control assessments but they are expensive and not widely available in most clinical settings. Increasingly, clinicians are using this technology to assess patients, however, the psychometric properties of these less sophisticated force plates is frequently unknown. The purposes of the study were to examine the test-retest reliability of a force plate commonly used by clinicians and to explore the effect of using the mean value from multiple repetitions on reliability. Thirty healthy volunteer adults were recruited. Postural control measures were obtained using the Midot Posture Scale Analyzer (MPSA). Data were collected in 2 sessions. Five successive repetitions each of 60 seconds duration were obtained from each participant in each session. The reliability coefficients obtained using single measures were low (ICC3,1 = 0.06 to 0.53). The average of two measures allowed for reliable measurements of COP mean velocity and average location of COP. The average of three and five measures was required to obtain acceptable reliability (ICC ≥ 0.70) of relative weight bearing on legs and sway area, respectively. Higher measurement precision values were seen by averaging four or five repetitions for all variables. Single measures did not provide reliable estimates of postural sway, and the averaging of multiple repetitions was necessary to achieve acceptable levels of measurement error. The number of repetitions required to achieve reliable data ranged from 2 to 5. Clinicians should be wary of using single measures derived from similar equipment when making decisions about patients.

  14. Reliability of center of pressure measures for assessing the development of sitting postural control through the stages of sitting.

    Science.gov (United States)

    Wickstrom, Jordan; Stergiou, Nick; Kyvelidou, Anastasia

    2017-07-01

    Cerebral palsy (CP) impairs an individual's ability to move and control one's posture. Unfortunately, the signs and symptoms of CP may not be apparent before age two. Evaluating sitting posture is a potential way to assess the developing mechanisms that contribute to CP. The purpose of this project was to determine the reliability of linear and nonlinear measures, including inter- and intrastage reliability, when used to analyze the center of pressure (COP) time series during the stages of sitting development in children with typical development (TD) and with/at-risk for cerebral palsy (CP). We hypothesized that nonlinear tools would be more reliable than linear tools in assessing childrens' sitting development, and reliability would increase with development. COP data was recorded for three trials at eight sessions. Linear parameters used were root mean square, range of sway for the anterior-posterior (AP) and medial-lateral (ML) directions, and sway path. Nonlinear parameters used were Approximate Entropy, the largest Lyapunov Exponent, and Correlation Dimension for the AP and ML direction. Participants consisted of 33 children with TD and 26 children with/at-risk for CP. Our results determined that COP is a moderately reliable method for assessing the development of sitting postural control in stages in both groups. Thus, clinicians may be able to use measures from COP data across stages to assess the efficacy of therapeutic interventions that are intended to improve sitting postural abilities in children with/at-risk for CP. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Unipedal Postural Balance and Countermovement Jumps After a Warm-up and Plyometric Training Session: A Randomized Controlled Trial.

    Science.gov (United States)

    Romero-Franco, Natalia; Jiménez-Reyes, Pedro

    2015-11-01

    The purpose of this study was to analyze the immediate effects of a plyometric training protocol on unipedal postural balance and countermovement jumps. In addition, we analyzed the effects of a warm-up on these parameters. Thirty-two amateur male sprinters (24.9 ± 4.1 years; 72.3 ± 10.7 kg; 1.78 ± 0.05 m; 22.6 ± 3.3 kg·m) were randomly sorted into a control group (n = 16) (they did not perform any physical activity) and a plyometric training group (n = 16) (they performed a 15-minute warm-up and a high-intensity plyometric protocol consisting of 10 sets of 15 vertical jumps). Before and after the warm-up, and immediately after and 5 minutes after the plyometric protocol, all athletes indicated the perceived exertion on calf and quad regions on a scale from 0 (no exertion) to 10 (maximum exertion). They also carried out a maximum countermovement jump and a unipedal postural balance test (athletes would remain as still as possible for 15 seconds in a left leg and right leg support stance). Results showed that, in the plyometric group, length and velocity of center-of-pressure movement in right leg support stance increased compared with baseline (p = 0.001 and p = 0.004, respectively) and to the control group (p = 0.035 and p = 0.029, respectively) immediately after the plyometric protocol. In addition, the countermovement jump height decreased right after the plyometric protocol (p plyometric exercises blunt unipedal postural balance and countermovement jump performance. The deterioration lasts at least 5 minutes, which may influence future exercises in the training session. Coaches should plan the training routine according to the immediate effects of plyometry on postural balance and vertical jumps, which play a role in injury prevention and sports performance.

  16. Supraspinal control of automatic postural responses in people with multiple sclerosis

    OpenAIRE

    Peterson, DS; Gera, G; Horak, FB; Fling, BW

    2016-01-01

    The neural underpinnings of delayed automatic postural responses in people with multiple sclerosis (PwMS) are unclear. We assessed whether white matter pathways of two supraspinal regions (the cortical proprioceptive Broadman���s Area-3; and the balance/locomotor-related pedunculopontine nucleus) were related to delayed postural muscle response latencies in response to external perturbations. 19 PwMS (48.8��11.4 years; EDSS=3.5 (range: 2���4)) and 12 healthy adults (51.7��12.2 years) underwen...

  17. Postural Control Can Be Well Maintained by Healthy, Young Adults in Difficult Visual Task, Even in Sway-Referenced Dynamic Conditions.

    Science.gov (United States)

    Lions, Cynthia; Bucci, Maria Pia; Bonnet, Cédrick

    2016-01-01

    To challenge the validity of existing cognitive models of postural control, we recorded eye movements and postural sway during two visual tasks (a control free-viewing task and a difficult searching task), and two postural tasks (one static task in which the platform was maintained stable and a dynamic task in which the platform moved in a sway-referenced manner.) We expected these models to be insufficient to predict the results in postural control both in static-as already shown in the literature reports-and in dynamic platform conditions. Twelve healthy, young adults (17.3 to 34.1 years old) participated in this study. Postural performances were evaluated using the Multitest platform (Framiral®) and ocular recording was performed with Mobile T2 (e(ye)BRAIN®). In the free-viewing task, the participants had to look at an image, without any specific instruction. In the searching task, the participants had to look at an image and also to locate the position of an object in the scene. Postural sway was only significantly higher in the dynamic free-viewing condition than in the three other conditions with no significant difference between these three other conditions. Visual task performance was slightly higher in dynamic than in static conditions. As expected, our results did not confirm the main assumption of the current cognitive models of postural control-i.e. that the limited attentional resources of the brain should explain changes in postural control in our conditions. Indeed, 1) the participants did not sway significantly more in the sway-referenced dynamic searching condition than in any other condition; 2) the participants swayed significantly less in both static and dynamic searching conditions than in the dynamic free-viewing condition. We suggest that a new cognitive model illustrating the adaptive, functional role of the brain to control upright stance is necessary for future studies.

  18. Postural Control Can Be Well Maintained by Healthy, Young Adults in Difficult Visual Task, Even in Sway-Referenced Dynamic Conditions.

    Directory of Open Access Journals (Sweden)

    Cynthia Lions

    Full Text Available To challenge the validity of existing cognitive models of postural control, we recorded eye movements and postural sway during two visual tasks (a control free-viewing task and a difficult searching task, and two postural tasks (one static task in which the platform was maintained stable and a dynamic task in which the platform moved in a sway-referenced manner. We expected these models to be insufficient to predict the results in postural control both in static-as already shown in the literature reports-and in dynamic platform conditions.Twelve healthy, young adults (17.3 to 34.1 years old participated in this study. Postural performances were evaluated using the Multitest platform (Framiral® and ocular recording was performed with Mobile T2 (e(yeBRAIN®. In the free-viewing task, the participants had to look at an image, without any specific instruction. In the searching task, the participants had to look at an image and also to locate the position of an object in the scene.Postural sway was only significantly higher in the dynamic free-viewing condition than in the three other conditions with no significant difference between these three other conditions. Visual task performance was slightly higher in dynamic than in static conditions.As expected, our results did not confirm the main assumption of the current cognitive models of postural control-i.e. that the limited attentional resources of the brain should explain changes in postural control in our conditions. Indeed, 1 the participants did not sway significantly more in the sway-referenced dynamic searching condition than in any other condition; 2 the participants swayed significantly less in both static and dynamic searching conditions than in the dynamic free-viewing condition. We suggest that a new cognitive model illustrating the adaptive, functional role of the brain to control upright stance is necessary for future studies.

  19. Age-Related Interference between the Selection of Input-Output Modality Mappings and Postural Control-a Pilot Study.

    Science.gov (United States)

    Stelzel, Christine; Schauenburg, Gesche; Rapp, Michael A; Heinzel, Stephan; Granacher, Urs

    2017-01-01

    Age-related decline in executive functions and postural control due to degenerative processes in the central nervous system have been related to increased fall-risk in old age. Many studies have shown cognitive-postural dual-task interference in old adults, but research on the role of specific executive functions in this context has just begun. In this study, we addressed the question whether postural control is impaired depending on the coordination of concurrent response-selection processes related to the compatibility of input and output modality mappings as compared to impairments related to working-memory load in the comparison of cognitive dual and single tasks. Specifically, we measured total center of pressure (CoP) displacements in healthy female participants aged 19-30 and 66-84 years while they performed different versions of a spatial one-back working memory task during semi-tandem stance on an unstable surface (i.e., balance pad) while standing on a force plate. The specific working-memory tasks comprised: (i) modality compatible single tasks (i.e., visual-manual or auditory-vocal tasks), (ii) modality compatible dual tasks (i.e., visual-manual and auditory-vocal tasks), (iii) modality incompatible single tasks (i.e., visual-vocal or auditory-manual tasks), and (iv) modality incompatible dual tasks (i.e., visual-vocal and auditory-manual tasks). In addition, participants performed the same tasks while sitting. As expected from previous research, old adults showed generally impaired performance under high working-memory load (i.e., dual vs. single one-back task). In addition, modality compatibility affected one-back performance in dual-task but not in single-task conditions with strikingly pronounced impairments in old adults. Notably, the modality incompatible dual task also resulted in a selective increase in total CoP displacements compared to the modality compatible dual task in the old but not in the young participants. These results suggest that

  20. Effects of support surface stability on feedback control of trunk posture.

    Science.gov (United States)

    Andreopoulou, Georgia; Maaswinkel, Erwin; Cofré Lizama, L Eduardo; van Dieën, Jaap H

    2015-04-01

    This study aimed to examine the interactions of visual, vestibular, proprioceptive, and tactile sensory manipulations and sitting on either a stable or an unstable surface on mediolateral (ML) trunk sway. Fifteen individuals were measured. In each trial, subjects sat as quiet as possible, on a stable or unstable surface, with or without each of four sensory manipulations: visual (eyes open/closed), vestibular (left and right galvanic vestibular stimulation alternating at 0.25 Hz), proprioceptive (left and right paraspinal muscle vibration alternating at 0.25 Hz), and tactile (minimal finger contact with object moving in the frontal plane at 0.25 Hz). The root mean square (RMS) and the power at 0.25 Hz (P25) of the ML trunk acceleration were the dependent variables. The latter was analyzed only for the rhythmic sensory manipulations and the reference condition. RMS was always significantly larger on the unstable than the stable surface. Closing the eyes caused a significant increase in RMS, more so on the unstable surface. Vestibular stimulation significantly increased RMS and P25 and more so on the unstable surface. Main effects of the proprioceptive manipulation were significant, but the interactions with surface condition were not. Finally, also tactile manipulation increased RMS and P25, but did not interact with surface condition. Sensory information in feedback control of trunk posture appears to be reweighted depending on stability of the environment. The absolute effects of visual and vestibular manipulations increase on an unstable surface, suggesting a relative decrease in the weights of proprioceptive and tactile information.

  1. Developing a dynamic virtual stimulation protocol to induce linear egomotion during orthostatic posture control test

    Directory of Open Access Journals (Sweden)

    Paulo José Guimarães Da-Silva

    Full Text Available Abstract Introduction In this work, the effect of a dynamic visual stimulation (DS protocol was used to induce egomotion, the center of pressure (COP displacement response. Methods DS was developed concerning the scenario structure (chessboard-pattern floor and furniture and luminance. To move the scenario in a discrete forward (or backward direction, the furniture is expanded (or reduced and the black and white background is reversed during floor translation while the luminance is increased (or reduced by steps of 2 cd/m2. This protocol was evaluated using COP signals from 29 healthy volunteers: standing on a force platform observing the virtual scene (1.72 × 1.16 m projected 1 m ahead (visual incidence angle: θl = 81.4° and θv = 60.2°, which moves with constant velocity (2 m/s during 250 ms. A set of 100 DS was applied in random order, interspersed by a 10 s of static scene. Results The Tukey post-hoc test (p < 0.001 indicated egomotion in the same direction of DS. COP displacement increased over stimulation (8.4 ± 1.7 to 22.6 ±5.3 mm, as well as time to recover stability (4.1 ± 0.4 to 7.2 ± 0.6 s. The peak of egomotion during DSF occurred 200 ms after DSB (Wilcoxon, p = 0.002. Conclusion The dynamic configuration of this protocol establishes virtual flow effects of linear egomotion dependent on the direction of the dynamic visual stimulation. This finding indicates the potential application of the proposed virtual dynamic stimulation protocol to investigate the cortical visual evoked response in postural control studies.

  2. Planckian Power Spectral Densities from Human Calves during Posture Maintenance and Controlled Isometric Contractions.

    Directory of Open Access Journals (Sweden)

    J E Lugo

    Full Text Available The relationship between muscle anatomy and physiology and its corresponding electromyography activity (EMGA is complex and not well understood. EMGA models may be broadly divided in stochastic and motor-unit-based models. For example, these models have successfully described many muscle physiological variables such as the value of the muscle fiber velocity and the linear relationship between median frequency and muscle fiber velocity. However they cannot explain the behavior of many of these variables with changes in intramuscular temperature, or muscle PH acidity, for instance. Here, we propose that the motor unit action potential can be treated as an electromagnetic resonant mode confined at thermal equilibrium inside the muscle. The motor units comprising the muscle form a system of standing waves or modes, where the energy of each mode is proportional to its frequency. Therefore, the power spectral density of the EMGA is well described and fit by Planck's law and from its distribution we developed theoretical relationships that explain the behavior of known physiological variables with changes in intramuscular temperature or muscle PH acidity, for instance.EMGA of the calf muscle was recorded during posture maintenance in seven participants and during controlled isometric contractions in two participants. The power spectral density of the EMGA was then fit with the Planckian distribution. Then, we inferred nine theoretical relationships from the distribution and compared the theoretically derived values with experimentally obtained values.The power spectral density of EMGA was fit by Planckian distributions and all the theoretical relationships were validated by experimental results.Only by considering the motor unit action potentials as electromagnetic resonant modes confined at thermal equilibrium inside the muscle suffices to predict known or new theoretical relationships for muscle physiological variables that other models have failed

  3. How an acute mastering of balance on a seesaw can improve the relationship between "static" and "dynamic" upright postural control.

    Science.gov (United States)

    Rougier, Patrice R

    2012-07-01

    Postural control ability has been widely evaluated using undisturbed upright stance protocols. However, standing on a seesaw may offer additional insights due to changes in the available sensory information and the amplification of the motor command resulting from the translational and rotational movement of the device. These two tasks share close biomechanical and neurophysiological principles. To highlight their possible linkage, 32 young healthy adults participated in this study, which consisted of testing postural performance while standing on a firm surface or on a seesaw producing rolling or pitching movements. The results showed increased CP displacements along the seesaw's pitching or rolling axis and also along the perpendicular axis. However, comparing the two tasks can be difficult because of discrepancies in the ability to rapidly master the new constraints brought about by the seesaw. To highlight the role played by adaptation, 15 subjects of the whole sample participated in a complementary protocol consisting of a 20-min training session aimed at improving the mastery of the seesaw producing pitch motions. The relationship between the amplitudes of the CP displacements between "static" and "dynamic" tasks was investigated. Interestingly, whereas no statistically significant linear correlation was found before training, several significant correlations were found after pitch training for AP displacements. By emphasizing the key role played by short-term adaptation in standing performance, these results are likely to have potential implications regarding the conception of standardized tests aimed at evaluating postural ability in healthy or disabled subjects. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. Feasibility and reliability of a virtual reality oculus platform to measure sensory integration for postural control in young adults.

    Science.gov (United States)

    Lubetzky, Anat V; Kary, Erinn E; Harel, Daphna; Hujsak, Bryan; Perlin, Ken

    2018-01-24

    Using Unity for the Oculus Development-Kit 2, we have developed an affordable, portable virtual reality platform that targets the visuomotor domain, a missing link in current clinical assessments of postural control. Here, we describe the design and technical development as well as report its feasibility with regards to cybersickness and test-retest reliability in healthy young adults. Our virtual reality paradigm includes two functional scenes ('City' and 'Park') and four moving dots scenes. Twenty-one healthy young adults were tested twice, one to two weeks apart. They completed a simulator sickness questionnaire several times per session. Their postural sway response was recorded from a forceplate underneath their feet while standing on the floor, stability trainers, or a Both Sides Up (BOSU) ball. Sample entropy, postural displacement, velocity, and excursion were calculated and compared between sessions given the visual and surface conditions. Participants reported slight-to-moderate transient side effects. Intra-Class Correlation values mostly ranged from 0.5 to 0.7 for displacement and velocity, were above 0.5 (stability trainer conditions) and above 0.4 (floor mediolateral conditions) for sample entropy, and minimal for excursion. Our novel portable VR platform was found to be feasible and reliable in healthy young adults.

  5. Adaptation of postural recovery responses to a vestibular sensory illusion in individuals with Parkinson disease and healthy controls.

    Science.gov (United States)

    Lester, Mark E; Cavanaugh, James T; Foreman, K Bo; Shaffer, Scott W; Marcus, Robin; Dibble, Leland E

    2017-10-01

    The ability to adapt postural responses to sensory illusions diminishes with age and is further impaired by Parkinson disease. However, limited information exists regarding training-related adaptions of sensory reweighting in these populations. This study sought to determine whether Parkinson disease or age would differentially affect acute postural recovery or adaptive postural responses to novel or repeated exposure to sensory illusions using galvanic vestibular stimulation during quiet stance. Acutely, individuals with Parkinson disease demonstrated larger center of pressure coefficient of variation compared to controls. Unlike individuals with Parkinson disease and asymptomatic older adults, healthy young adults acutely demonstrated a reduction in Sample Entropy to the sensory illusion. Following a period of consolidation Sample Entropy increased in the healthy young group, which coincided with a decreased center of pressure coefficient of variation. Similar changes were not observed in the Parkinson disease or older adult groups. Taken together, these results suggest that young adults learn to adapt to vestibular illusion in a more robust manner than older adults or those with Parkinson disease. Further investigation into the nature of this adaptive difference is warranted. Published by Elsevier Ltd.

  6. Hemispheric specificity for proprioception: Postural control of standing following right or left hemisphere damage during ankle tendon vibration.

    Science.gov (United States)

    Duclos, Noémie C; Maynard, Luc; Abbas, Djawad; Mesure, Serge

    2015-11-02

    Right brain damage (RBD) following stroke often causes significant postural instability. In standing (without vision), patients with RBD are more unstable than those with left brain damage (LBD). We hypothesised that this postural instability would relate to the cortical integration of proprioceptive afferents. The aim of this study was to use tendon vibration to investigate whether these changes were specific to the paretic or non-paretic limbs. 14 LBD, 12 RBD patients and 20 healthy subjects were included. Displacement of the Centre of Pressure (CoP) was recorded during quiet standing, then during 3 vibration conditions (80 Hz - 20s): paretic limb, non-paretic limb (left and right limbs for control subjects) and bilateral. Vibration was applied separately to the peroneal and Achilles tendons. Mean antero-posterior position of the CoP, variability and velocity were calculated before (4s), during and after (24s) vibration. For all parameters, the strongest perturbation was during Achilles vibrations. The Achilles non-paretic condition induced a larger backward displacement than the Achilles paretic condition. This condition caused specific behaviour on the velocity: the LBD group was perturbed at the onset of the vibrations, but gradually recovered their stability; the RBD group was significantly perturbed thereafter. After bilateral Achilles vibration, RBD patients required the most time to restore initial posture. The reduction in use of information from the paretic limb may be a central strategy to deal with risk-of-fall situations such as during Achilles vibration. The postural behaviour is profoundly altered by lesions of the right hemisphere when proprioception is perturbed. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Kinematic characteristics of postural control during reaching in preterm children with cerebral palsy

    NARCIS (Netherlands)

    Van Der Heide, JC; Folk, JM; Otten, Bert; Stremmelaar, E; Hadders-Algra, M

    The relationships between kinematic characteristics of sitting posture during reaching movements of the dominant arm and I) the kinematics of the reaching movement itself and 2) functional performance during daily life activities (PEDI) were assessed in 51 sitting preterm children with cerebral

  8. Unifying model of shoot gravitropism reveals proprioception as a central feature of posture control in plants

    DEFF Research Database (Denmark)

    Bastien, Renaud; Bohr, Tomas; Moulia, Bruno

    2012-01-01

    Gravitropism, the slow reorientation of plant growth in response to gravity, is a key determinant of the form and posture of land plants. Shoot gravitropism is triggered when statocysts sense the local angle of the growing organ relative to the gravitational field. Lateral transport of the hormone...

  9. A Study on Bipedal and Mobile Robot Behavior Through Modeling and Simulation

    Directory of Open Access Journals (Sweden)

    Nirmala Nirmala

    2015-05-01

    Full Text Available The purpose of this work is to study and analyze mobile robot behavior. In performing this, a framework is adopted and developed for mobile and bipedal robot. The robots are design, build, and run as proceed from the development of mechanical structure, electronics and control integration, and control software application. The behavior of those robots are difficult to be observed and analyzed qualitatively. To evaluate the design and behavior quality, modeling and simulation of robot structure and its task capability is performed. The stepwise procedure to robot behavior study is explained. Behavior cases study are experimented to bipedal robots, transporter robot and Autonomous Guided Vehicle (AGV developed at our institution. The experimentation are conducted on those robots by adjusting their dynamic properties and/or surrounding environment. Validation is performed by comparing the simulation result and the real robot execution. The simulation gives a more idealistic behavior execution rather than realistic one. Adjustments are performed to fine tuning simulation's parameters to provide a more realistic performance.

  10. 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.

  11. Fossils, feet and the evolution of human bipedal locomotion.

    Science.gov (United States)

    Harcourt-Smith, W E H; Aiello, L C

    2004-05-01

    We review the evolution of human bipedal locomotion with a particular emphasis on the evolution of the foot. We begin in the early twentieth century and focus particularly on hypotheses of an ape-like ancestor for humans and human bipedal locomotion put forward by a succession of Gregory, Keith, Morton and Schultz. We give consideration to Morton's (1935) synthesis of foot evolution, in which he argues that the foot of the common ancestor of modern humans and the African apes would be intermediate between the foot of Pan and Hylobates whereas the foot of a hypothetical early hominin would be intermediate between that of a gorilla and a modern human. From this base rooted in comparative anatomy of living primates we trace changing ideas about the evolution of human bipedalism as increasing amounts of postcranial fossil material were discovered. Attention is given to the work of John Napier and John Robinson who were pioneers in the interpretation of Plio-Pleistocene hominin skeletons in the 1960s. This is the period when the wealth of evidence from the southern African australopithecine sites was beginning to be appreciated and Olduvai Gorge was revealing its first evidence for Homo habilis. In more recent years, the discovery of the Laetoli footprint trail, the AL 288-1 (A. afarensis) skeleton, the wealth of postcranial material from Koobi Fora, the Nariokotome Homo ergaster skeleton, Little Foot (Stw 573) from Sterkfontein in South Africa, and more recently tantalizing material assigned to the new and very early taxa Orrorin tugenensis, Ardipithecus ramidus and Sahelanthropus tchadensis has fuelled debate and speculation. The varying interpretations based on this material, together with changing theoretical insights and analytical approaches, is discussed and assessed in the context of new three-dimensional morphometric analyses of australopithecine and Homo foot bones, suggesting that there may have been greater diversity in human bipedalism in the earlier phases

  12. Mechanosensing Potentials Gate Fuel Consumption in a Bipedal DNA Nanowalker

    Science.gov (United States)

    Tee, Shern Ren; Hu, Xinpeng; Loh, Iong Ying; Wang, Zhisong

    2018-03-01

    A bipedal DNA nanowalker was recently reported to convert chemical energy into directional motion autonomously and efficiently. To elucidate its chemomechanical coupling mechanisms, three-dimensional molecular modeling is used to obtain coarse-grained foot-track binding potentials of the DNA nanowalker via unbiased and biased sampling techniques (for the potentials' basin and high-energy edges, respectively). The binding state that is protected against fuel-induced dissociation responds asymmetrically to forward versus backward forces, unlike the unprotected state, demonstrating a mechanosensing capability to gate fuel binding. Despite complex DNA mechanics, the foot-track potential exhibits a surprisingly neat three-part profile, offering some general guidelines to rationally design efficient nanowalkers. Subsequent modeling of the bipedal walker attached to the track gives estimates of the free energy for each bipedal state, showing how the mechanosensing foot-track binding breaks the symmetry between the rear and front feet, enabling the rear foot to be selectively dissociated by fuel and generating efficient chemomechanical coupling.

  13. Effects of a high intensity intermitent exercise on the postural dynamic control of semi pro football players

    Directory of Open Access Journals (Sweden)

    Luis Francisco Royán-González

    2017-11-01

    Full Text Available The purpose of this research was to study how intermittent high intensity exercise affects dynamic postural control in soccer players of the 3rd Spanish Division. Through an intermittent effort test (Yo-Yo Intermittent test 1 the players are subjected to a fatigue situation in order to observe the incidence of dynamic postural control, whose alteration is related to the increased risk of sports injuries. Fatigue is an element that brings with it a series of physiological changes and makes our motor response ineffective due to the diversity of stimuli offered by a sport such as football, and can trigger in an injury, the epidemiology of football shows us the importance of the control of Fatigue and its consequences on the actions of players. Objective. To verify the incidence of fatigue in dynamic postural control. Design. Pre experimental, pre and post treatment of a group. Population. Twelve male players (Age = 4 ± 5.3 years, height = 1.81 ± 0.04 m, weight = 76.8 ± 6.35, fat% = 11.9 ± 0.99% Method. We performed a pre-test Y Balance Test (YBT, we immediately induce fatigue through Yo-Yo Intermittent test 1, when the player completes the test we obtain lactam sample in blood and perform a post test YBT to see the differences After induced fatigue. Heart rate (HR was monitored throughout the process to obtain maximum heart rate (HRmax and the subjective perception of exertion of the players was controlled using Borg scale. Results. After performing a Student's T, we compared the pre and post means in order to verify if there were significant differences. All the scopes declined in the post-test, but significantly the right frontal range (p <0, 0100, right postero-lateral (p <0.0000 and left postero-medial range (p <0.0130. Pearson's correlation r found positive but not significant relationships between variables. Conclusion. With the data obtained, we can say that fatigue induced through a test of high intermittent intensity adversely affects

  14. Immediate effects of Pilates based therapeutic exercise on postural control of young individuals with non-specific low back pain: A randomized controlled trial.

    Science.gov (United States)

    Lopes, Susana; Correia, Christophe; Félix, Gonçalo; Lopes, Mário; Cruz, Ana; Ribeiro, Fernando

    2017-10-01

    Low back pain affects the person's ability to keep balance, especially in challenging conditions. The purpose of this study was to determine the immediate effects of Pilates exercises on postural sway and dynamic balance of young individuals with non-specific low back pain. Controlled laboratory design. Forty-six participants with non-specific low back pain were randomized to a Pilates (n=23, 10 males; age: 21.8±3.2years) and a control group (n=23, 9 males; age: 22.8±3.6years). Postural sway was assessed with a force platform and dynamic balance with the Star Excursion Balance Test, before and after the intervention or rest period. To assess postural sway, participants stood still on an unstable surface set on the force plate for 90s, with eyes closed. The intervention lasted 20min and consisted on four Pilates exercises: single leg stretch (level 1), pelvic press (level 1), swimming (level 1) and kneeling opposite arm and leg reach. At baseline, no differences were found between groups. The Pilates group improved in all the postural sway values (area of CoP: 11.5±3.4 to 9.7±2.7cm 2 , p=0.002 and CoP velocity: 2.8±0.6 to 2.3±0.5cm/s, pPilates group. Pilates exercises immediately improved postural sway and dynamic balance in young adults with non-specific low back pain. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Effect of a single session of ear acupuncture on pain intensity and postural control in individuals with chronic low back pain: a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Andrea Ushinohama

    2016-01-01

    Full Text Available ABSTRACT Background Ear Acupuncture (EA is a form of acupuncture in which needles are applied to the external ear and has been used in multiple painful conditions. Low back pain (LBP is highly prevalent in active individuals and causes high economic burden to health systems worldwide. LBP affects the person’s ability to keep balance, especially in challenging conditions. Objective The aim of the study was to examine the effects of a single session of EA on pain intensity and body sway during postural tasks. Method Eighty adults with LBP and pain intensity equal to or greater than 4 (0-10 scale were randomly allocated (1:1 to EA group (EAG or placebo group (PG. Initially, the level of pain intensity was assessed. Next, participants stood still on a force plate either with feet in parallel or in semi-tandem and with eyes open or closed. Then, the EAG was treated with EA for 20 min and the PG was treated with detuned ultrasound. After the treatment, pain intensity was assessed again and the postural test was repeated. Pain intensity was the primary outcome and center of pressure sway area and speed were the secondary outcomes measured. Results Results revealed that pain intensity decreased in both groups after treatment, but decreased more in the EAG. For postural control, no effect of treatment and no interaction between treatment and postural condition on body sway were found. Conclusion Those findings indicate that EA is better than placebo to reduce pain, but neither treatment has any effect on postural control.

  16. Effects of low back pain and of stabilization or movement-system-impairment treatments on induced postural responses: A planned secondary analysis of a randomised controlled trial.

    Science.gov (United States)

    Jacobs, Jesse V; Lomond, Karen V; Hitt, Juvena R; DeSarno, Michael J; Bunn, Janice Y; Henry, Sharon M

    2016-02-01

    Motor retraining for non-specific chronic low back pain (LBP) often focuses on voluntary postural tasks. This training, however, may not transfer to other known postural impairments, such as automatic postural responses to external perturbations. To evaluate the extent current treatments of motor retraining ameliorate impaired postural coordination when responding to a perturbation of standing balance. Planned secondary analysis of a prospectively registered (NCT01362049), randomized controlled trial with a blinded assessor. Sixty-eight subjects with chronic, recurrent, non-specific LBP were allocated to perform a postural response task as a secondary assessment one week before and one week after receiving either stabilization or Movement System Impairment (MSI)-directed treatment over 6 weekly 1-h sessions plus home exercises. For assessment, subjects completed the Oswestry disability and numeric pain rating questionnaires and then performed a postural response task of maintaining standing balance in response to 3 trials in each of 4 randomly presented directions of linear surface translations of the platform under the subjects' feet. Integrated amplitudes of surface electromyography (EMG) were recorded bilaterally from the rectus abdominis (RA), internal oblique (IO), and external oblique (EO) muscles during the postural response task. No significant effects of treatment on EMG responses were evident. Oswestry and numeric pain ratings decreased similarly following both treatments. Stabilization and MSI-directed treatments do not affect trunk EMG responses to perturbations of standing balance in people with LBP, suggesting current methods of motor retraining do not sufficiently transfer to tasks of reactive postural control. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Introduction to Focus Issue: Bipedal Locomotion-From Robots to Humans

    Science.gov (United States)

    Milton, John G.

    2009-06-01

    Running and walking, collectively referred to as bipedal locomotion, represent self-organized behaviors generated by a spatially distributed dynamical system operating under the constraint that a person must be able to move without falling down. The organizing principles involve both forces actively regulated by the nervous system and those generated passively by the biomechanical properties of the musculoskeletal system and the environment in which the movements occur. With the development of modern motion capture and electrophysiological techniques it has become possible to explore the dynamical interplay between the passive and active controllers of locomotion in a manner that directly compares observation to predictions made by relevant mathematical and computer models. Consequently, many of the techniques initially developed to study nonlinear dynamical systems, including stability analyses, phase resetting and entrainment properties of limit cycles, and fractal and multifractal analysis, have come to play major roles in guiding progress. This Focus Issue discusses bipedal locomotion from the point of view of dynamical systems theory with the goal of stimulating discussion between the dynamical systems, physics, biomechanics, and neuroscience communities.

  18. A bipedal DNA motor that travels back and forth between two DNA origami tiles.

    Science.gov (United States)

    Liber, Miran; Tomov, Toma E; Tsukanov, Roman; Berger, Yaron; Nir, Eyal

    2015-02-04

    In this work, the successful operation of a dynamic DNA device constructed from two DNA origami building blocks is reported. The device includes a bipedal walker that strides back and forth between the two origami tiles. Two different DNA origami tiles are first prepared separately; they are then joined together in a controlled manner by a set of DNA strands to form a stable track in high yield as confirmed by single-molecule fluorescence (SMF). Second, a bipedal DNA motor, initially attached to one of the two origami units and operated by sequential interaction with "fuel" and "antifuel" DNA strands, moves from one origami tile to another and then back again. The operational yield, measured by SMF, was similar to that of a motor operating on a similar track embedded in a single origami tile, confirming that the transfer across the junction from one tile to the other does not result in dissociation that is any more than that of steps on a single tile. These results demonstrate that moving parts can reliably travel from one origami unit to another, and it demonstrates the feasibility of dynamic DNA molecular machines that are made of more than a single origami building block. This study is a step toward the development of motors that can stride over micrometer distances. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. The assessment of postural control and the influence of a secondary task in people with anterior cruciate ligament reconstructed knees using a Nintendo Wii Balance Board.

    Science.gov (United States)

    Howells, Brooke E; Clark, Ross A; Ardern, Clare L; Bryant, Adam L; Feller, Julian A; Whitehead, Timothy S; Webster, Kate E

    2013-09-01

    Postural control impairments may persist following anterior cruciate ligament (ACL) reconstruction. The effect of a secondary task on postural control has, however, not been determined. The purpose of this case-control study was to compare postural control in patients following ACL reconstruction with healthy individuals with and without a secondary task. 45 patients (30 men and 15 women) participated at least 6 months following primary ACL reconstruction surgery. Participants were individually matched by age, gender and sports activity to healthy controls. Postural control was measured using a Nintendo Wii Balance Board and customised software during static single-leg stance and with the addition of a secondary task. The secondary task required participants to match the movement of an oscillating marker by adducting and abducting their arm. Centre of pressure (CoP) path length in both medial-lateral and anterior-posterior directions, and CoP total path length. When compared with the control group, the anterior-posterior path length significantly increased in the ACL reconstruction patients' operated (12.3%, p=0.02) and non-operated limbs (12.8%, p=0.02) for the single-task condition, and the non-operated limb (11.5%, p=0.006) for the secondary task condition. The addition of a secondary task significantly increased CoP path lengths in all measures (p<0.001), although the magnitude of the increase was similar in both the ACL reconstruction and control groups. ACL reconstruction patients showed a reduced ability in both limbs to control the movement of the body in the anterior-posterior direction. The secondary task affected postural control by comparable amounts in patients after ACL reconstruction and healthy controls. Devices for the objective measurement of postural control, such as the one used in this study, may help clinicians to more accurately identify patients with deficits who may benefit from targeted neuromuscular training programs.

  20. A multicentre randomized controlled trial of gentle assisted pushing in the upright posture (GAP) or upright posture alone compared with routine practice to reduce prolonged second stage of labour (the Gentle Assisted Pushing study): study protocol.

    Science.gov (United States)

    Hofmeyr, G Justus; Singata, Mandisa; Lawrie, Theresa; Vogel, Joshua P; Landoulsi, Sihem; Seuc, Armando H; Gülmezoglu, A Metin

    2015-12-16

    Fundal pressure (pushing on the upper part of the uterus in the direction of the birth canal) is often performed in routine practice, however the benefit and indications for its use are unclear and vigorous pressure is potentially harmful. There is some evidence that it may be applied routinely or to expedite delivery in some situations (e.g. fetal distress or maternal exhaustion), particularly in settings where other methods of achieving delivery (forceps, vacuum) are not available. Gentle assisted pushing (GAP) is an innovative method of applying gentle but steady pressure to the uterine fundus with the woman in an upright posture. This trial aims to evaluate the use of GAP in an upright posture, or upright posture alone, on reducing the mean time of delivery and the associated maternal and neonatal complications in women not having delivered following 15-30 min in the second stage of labour. We will conduct a multicentre, randomized, unblinded, controlled trial with three parallel arms (1:1:1). 1,145 women will be randomized at three hospitals in South Africa. Women will be eligible for inclusion if they are ≥18 years old, nulliparous, gestational age ≥ 35 weeks, have a singleton pregnancy in cephalic presentation and vaginal delivery anticipated. Women with chronic medical conditions or obstetric complications are not eligible. If eligible women are undelivered following 15-30 min in the second stage of labour, they will be randomly assigned to: 1) GAP in the upright posture, 2) upright posture only and 3) routine practice (recumbent/supine posture). The primary outcome is the mean time from randomization to complete delivery. Secondary outcomes include operative delivery, adverse neonatal outcomes, maternal adverse events and discomfort. This trial will establish whether upright posture and/or a controlled method of applying fundal pressure (GAP) can improve labour outcomes for women and their babies. If fundal pressure is found to have a measurable

  1. Age-related changes in human posture control: Motor coordination tests

    Science.gov (United States)

    Peterka, R. J.; Black, F. O.

    1989-01-01

    Postural responses to support surface displacements were measured in 214 normal human subjects ranging in age from 7 to 81 years. Motor tests measured leg muscle Electromyography (EMG) latencies, body sway, and the amplitude and timing of changes in center of pressure displacements in response to sudden forward and backward horizontal translations of the support surface upon which the subjects stood. There were small increases in both EMG latencies and the time to reach the peak amplitude of center of pressure responses with increasing age. The amplitude of center of pressure responses showed little change with age if the amplitude measures were normalized by a factor related to subject height. In general, postural responses to sudden translations showed minimal changes with age, and all age related trends which were identified were small relative to the variability within the population.

  2. Postural control in elderly persons with osteoporosis: Efficacy of an intervention program to improve balance and muscle strength: a randomized controlled trial.

    Science.gov (United States)

    Burke, Thomaz Nogueira; França, Fábio Jorge Renovato; Ferreira de Meneses, Sarah Rúbia; Cardoso, Viviam Inhasz; Marques, Amélia Pasqual

    2010-07-01

    To assess the efficacy of an exercise program aiming to improve balance and muscular strength, for postural control and muscular strength of women with osteoporosis. Sample consisted of 33 women with osteoporosis, randomized into one of two groups: intervention group, in which exercises for balance and improvement of muscular strength of the inferior members were performed for 8 wks (n = 17, age 72.8 +/- 3.6 yrs); control group, which was women not practicing exercises (n = 16, age 74.4 +/- 3.7 yrs). At baseline and after 8 wks of treatment, postural control was assessed using a force plate (Balance Master, Neurocom), and muscular strength during ankle dorsiflexion, knee extension, and flexion was assessed by dynamometry. Adherence to the program was 82%. When compared with the control group, individuals in the intervention group significantly improved the center of pressure velocity (P = 0.02) in the modified clinical test of sensory interaction for balance test, center of pressure velocity (P strength exercises are effective in improving postural control and lower-limb strength in elderly women with osteoporosis.

  3. Effectiveness of a 'Global Postural Reeducation' program for persistent Low Back Pain: a non-randomized controlled trial

    OpenAIRE

    Bonetti, Francesca; Curti, Stefania; Mattioli, Stefano; Mugnai, Raffaele; Vanti, Carla; Violante, Francesco S; Pillastrini, Paolo

    2010-01-01

    Abstract Background The aim of this non-randomized controlled trial was to evaluate the effectiveness of a Global Postural Reeducation (GPR) program as compared to a Stabilization Exercise (SE) program in subjects with persistent low back pain (LBP) at short- and mid-term follow-up (ie. 3 and 6 months). Methods According to inclusion and exclusion criteria, 100 patients with a primary complaint of persistent LBP were enrolled in the study: 50 were allocated to the GPR group and 50 to the SE g...

  4. Ramadan Fasting Effects on Postural Control in the Elderly: A Comparison Between Fallers and Non-fallers.

    Science.gov (United States)

    Laatar, Rabeb; Baccouch, Rym; Borji, Rihab; Kachouri, Hiba; Rebai, Haithem; Sahli, Sonia

    2016-11-01

    Our purpose was to compare the effects of Ramadan fasting on postural control in elderly fallers and non-fallers. The protocol involved twenty-four healthy old volunteer males divided into two groups: fallers (mean age = 75.43 ± 5.26 years, weight = 67.25 ± 5.30 kg and height = 1.65 ± 0.02 m) and non-fallers (mean age = 72.3 ± 6.42 years, weight = 65.5 ± 6.15 kg and height = 1.64 ± 0.03 m). Participants performed a simple reaction time test (SRT) and a postural control protocol on four different occasions: one week before Ramadan (BR), during the second (SWR) and the fourth week (FWR) of Ramadan and three weeks after Ramadan (AR). Center of pressure (CoP) parameters [the CoP medial-lateral length (CoP X ), and the CoP antero-posterior length (CoP Y )] were assessed using a force platform under two surface conditions: Firm surface and Foam surface. The results showed that Ramadan fasting influences similarly fallers and non-fallers. In fact, for both groups, the CoP X and the CoP Y values increased significantly during the SWR and the FWR compared to BR. These CoP parameters decreased significantly in the Firm surface conditions in the FWR. Moreover, the CoP parameters were significantly higher during the FWR and AR in comparison with BR in the Foam surface conditions. However, the amplitude of increase of the CoP [X] % and the CoP [Y] % (ΔCoP [X] % and ΔCoP [Y] %) between BR and the SWR was significantly higher in the fallers than non-fallers. The SRT of elderly fallers and non-fallers was significantly higher in the SWR and in the FWR compared to BR. In conclusion, Ramadan fasting alters similarly postural control of elderly fallers and non-fallers, but the amplitude (ΔCoP [X] % and ΔCoP [Y] %) of this alteration seems to be more pronounced in fallers than non-fallers. A probable beginning of adaptation occurs at the FWR. However, three weeks seems to be insufficient to recover postural control alterations due to Ramadan

  5. Efectividad del tratamiento del control postural utilizando la Nitendo Wii en pacientes hemipléjicos adultos post ACV

    OpenAIRE

    Lino, María Belén

    2014-01-01

    La hemiplejia post ACV es una patología neurológica con gran incidencia y prevalencia mundial como causa de mortalidad y de discapacidad física. El kinesiólogo debe aplicar y desarrollar múltiples enfoques terapéuticos dentro del área de la neurorehabilitación. Una de las nuevas herramientas es la terapia virtual que se incorpora junto al resto de los tratamientos convencionales. Objetivo: Evaluar la efectividad del tratamiento del control postural a través de un abordaje te...

  6. Study II: mechanoreceptive sensation is of increased importance for human postural control under alcohol intoxication.

    Science.gov (United States)

    Modig, F; Patel, M; Magnusson, M; Fransson, P A

    2012-03-01

    Standing postural stability relies on input from visual, vestibular, proprioceptive and mechanoreceptive sensors. When the information from any of these sensors is unavailable or disrupted, the central nervous system maintains postural stability by relying more on the contribution from the reliable sensors, termed sensory re-weighting. Alcohol intoxication is known to affect the integrity of the vestibular and visual systems. The aim was to assess how mechanoreceptive sensory information contributed to postural stability at 0.00% (i.e. sober), 0.06% and 0.10% blood alcohol concentration (BAC) in 25 healthy subjects (mean age 25.1 years). The subjects were assessed with eyes closed and eyes open under quiet standing and while standing was perturbed by repeated, random-length, vibratory stimulation of the calf muscles. Plantar cutaneous mechanoreceptive sensation was assessed for both receptor types: slowly adapting (tactile sensitivity) and rapidly adapting (vibration perception). The correlation between recorded torque variance and the sensation from both mechanoreceptor types was calculated. The recorded stability during alcohol intoxication was significantly influenced by both the tactile sensation and vibration perception of the subjects. Moreover, the study revealed a fluctuating association between the subjects' vibration perception and torque variance during balance perturbations, which was significantly influenced by the level of alcohol intoxication, vision and adaptation. Hence, one's ability to handle balance perturbations under the influence of alcohol is strongly dependent on accurate mechanoreceptive sensation and efficient sensory re-weighting. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. Postural control is not systematically related to reading skills: implications for the assessment of balance as a risk factor for developmental dyslexia.

    Directory of Open Access Journals (Sweden)

    Håvard Loras

    Full Text Available Impaired postural control has been associated with poor reading skills, as well as with lower performance on measures of attention and motor control variables that frequently co-occur with reading difficulties. Measures of balance and motor control have been incorporated into several screening batteries for developmental dyslexia, but it is unclear whether the relationship between such skills and reading manifests as a behavioural continuum across the range of abilities or is restricted to groups of individuals with specific disorder phenotypes. Here were obtained measures of postural control alongside measures of reading, attention and general cognitive skills in a large sample of young adults (n = 100. Postural control was assessed using centre of pressure (CoP measurements, obtained over 5 different task conditions. Our results indicate an absence of strong statistical relationships between balance measures with either reading, cognitive or attention measures across the sample as a whole.

  8. Exercise-induced muscle fatigue in the unaffected knee joint and its influence on postural control and lower limb kinematics in stroke patients

    Directory of Open Access Journals (Sweden)

    Sun Wook Park

    2017-01-01

    Full Text Available This study aimed to investigate the effects of exercise-induced muscle fatigue in the unaffected knee joint on postural control and kinematic changes in stroke patients. Forty participants (20 stroke patients, 20 age-matched healthy participants were recruited. To induce fatigue, maximum voluntary isometric contractions were performed in the unaffected knee joint in a Leg Extension Rehab exercise machine using the pneumatic resistance. We measured static and dynamic balance and lower-limb kinematics during gait. Changes in postural control parameters anteroposterior sway speed and total center of pressure distance differed significantly between the stroke and control groups. In addition, changes in gait kinematic parameters knee and ankle angles of initial contact differed significantly between stroke (paretic and non-paretic and control groups. Muscle fatigue in the unaffected knee and ankle impaired postural control and debilitates kinematic movement of ipsilateral and contralateral lower limbs, and may place the fatigued stroke patients at greater risk for falls.

  9. The Effect of Continuous and Discretized Presentations of Concurrent Augmented Visual Biofeedback on Postural Control in Quiet Stance.

    Directory of Open Access Journals (Sweden)

    Carmen D'Anna

    Full Text Available The purpose of this study was to evaluate the effect of a continuous and a discretized Visual Biofeedback (VBF on balance performance in upright stance. The coordinates of the Centre of Pressure (CoP, extracted from a force plate, were processed in real-time to implement the two VBFs, administered to two groups of 12 healthy participants. In the first group, a representation of the CoP was continuously shown, while in the second group, the discretized VBF was provided at an irregular frequency (that depended on the subject's performance by displaying one out of a set of five different emoticons, each corresponding to a specific area covered by the current position of the CoP. In the first case, participants were asked to maintain a white spot within a given square area, whereas in the second case they were asked to keep the smiling emoticon on. Trials with no VBF were administered as control. The effect of the two VBFs on balance was studied through classical postural parameters and a subset of stabilogram diffusion coefficients. To quantify the amount of time spent in stable conditions, the percentage of time during which the CoP was inside the stability area was calculated. Both VBFs improved balance maintainance as compared to the absence of any VBF. As compared to the continuous VBF, in the discretized VBF a significant decrease of sway path, diffusion and Hurst coefficients was found. These results seem to indicate that a discretized VBF favours a more natural postural behaviour by promoting a natural intermittent postural control strategy.

  10. The Effect of Continuous and Discretized Presentations of Concurrent Augmented Visual Biofeedback on Postural Control in Quiet Stance.

    Science.gov (United States)

    D'Anna, Carmen; Schmid, Maurizio; Bibbo, Daniele; Bertollo, Maurizio; Comani, Silvia; Conforto, Silvia

    2015-01-01

    The purpose of this study was to evaluate the effect of a continuous and a discretized Visual Biofeedback (VBF) on balance performance in upright stance. The coordinates of the Centre of Pressure (CoP), extracted from a force plate, were processed in real-time to implement the two VBFs, administered to two groups of 12 healthy participants. In the first group, a representation of the CoP was continuously shown, while in the second group, the discretized VBF was provided at an irregular frequency (that depended on the subject's performance) by displaying one out of a set of five different emoticons, each corresponding to a specific area covered by the current position of the CoP. In the first case, participants were asked to maintain a white spot within a given square area, whereas in the second case they were asked to keep the smiling emoticon on. Trials with no VBF were administered as control. The effect of the two VBFs on balance was studied through classical postural parameters and a subset of stabilogram diffusion coefficients. To quantify the amount of time spent in stable conditions, the percentage of time during which the CoP was inside the stability area was calculated. Both VBFs improved balance maintainance as compared to the absence of any VBF. As compared to the continuous VBF, in the discretized VBF a significant decrease of sway path, diffusion and Hurst coefficients was found. These results seem to indicate that a discretized VBF favours a more natural postural behaviour by promoting a natural intermittent postural control strategy.

  11. Center of Mass Acceleration Feedback Control of Functional Neuromuscular Stimulation for Standing in the Presence of Internal Postural Perturbations

    Science.gov (United States)

    Audu, Musa L.; Triolo, Ronald J.

    2013-01-01

    This study determined the feasibility and performance of center of mass (COM) acceleration feedback control of a neuroprosthesis utilizing functional neuromuscular stimulation (FNS) to restore standing balance to a single subject paralyzed by a motor and sensory complete, thoracic-level spinal cord injury (SCI). An artificial neural network (ANN) was created to map gain-modulated changes in total body COM acceleration estimated from body-mounted sensors to optimal changes in stimulation required to maintain standing. Feedback gains were systematically tuned to minimize the upper extremity (UE) loads applied by the subject to an instrumented support device during internally generated postural perturbations produced by volitional reaching and object manipulation. Total body COM acceleration was accurately estimated (> 90% variance explained) from two three-dimensional (3-D) accelerometers mounted on the pelvis and torso. Compared to constant muscle stimulation employed clinically, COM acceleration feedback control of stimulation improved standing performance by reducing the UE loading required to resist internal postural disturbances by 27%. This case study suggests that COM acceleration feedback could potentially be advantageous in a standing neuroprosthesis since it can be implemented with only a few feedback parameters and requires minimal instrumentation for comprehensive, 3-D control of dynamic standing function. PMID:23299260

  12. Persistence of improvements in postural strategies following motor control training in people with recurrent low back pain.

    Science.gov (United States)

    Tsao, Henry; Hodges, Paul W

    2008-08-01

    This study investigated long-term effects of training on postural control using the model of deficits in activation of transversus abdominis (TrA) in people with recurrent low back pain (LBP). Nine volunteers with LBP attended four sessions for assessment and/or training (initial, two weeks, four weeks and six months). Training of repeated isolated voluntary TrA contractions were performed at the initial and two-week session with feedback from real-time ultrasound imaging. Home program involved training twice daily for four weeks. Electromyographic activity (EMG) of trunk and deltoid muscles was recorded with surface and fine-wire electrodes. Rapid arm movement and walking were performed at each session, and immediately after training on the first two sessions. Onset of trunk muscle activation relative to prime mover deltoid during arm movements, and the coefficient of variation (CV) of EMG during averaged gait cycle were calculated. Over four weeks of training, onset of TrA EMG was earlier during arm movements and CV of TrA EMG was reduced (consistent with more sustained EMG activity). Changes were retained at six months follow-up (p<0.05). These results show persistence of motor control changes following training and demonstrate that this training approach leads to motor learning of automatic postural control strategies.

  13. Variability in postural control with and without balance-based torso- weighting in people with multiple sclerosis and healthy controls.

    Science.gov (United States)

    Hunt, Charlotte M; Widener, Gail; Allen, Diane D

    2014-10-01

    People with multiple sclerosis (MS) have diminished postural control, and center of pressure (COP) displacement varies more in this population than in healthy controls. Balance-based torso-weighting (BBTW) can improve clinical balance and mobility in people with MS, and exploration using both linear and nonlinear measures of COP may help determine whether BBTW optimizes movement variability. The aim of this study was to investigate the effects of BBTW on people with MS and healthy controls during quiet standing. This was a quasi-experimental study comparing COP variability between groups, between eye closure conditions, and between weighting conditions in the anterior-posterior and medial-lateral directions. Twenty participants with MS and 18 healthy controls stood on a forceplate in 4 conditions: eyes open and closed and with and without BBTW. Linear measures of COP displacement included range and root mean square (RMS). Nonlinear measures included approximate entropy (ApEn) and Lyapunov exponent (LyE). Three-way repeated-measures analyses of variance compared measures across groups and conditions. The association between weighting response and baseline nonlinear variables was examined. When significant associations were found, MS subgroups were created and compared. The MS and control groups had significantly different range, RMS, and ApEn values. The eyes-open and eyes-closed conditions had significantly different range and RMS values. Change with weighting correlated with LyE (r=-.70) and ApEn (r=-.59). Two MS subgroups, with low and high baseline LyE values, responded to BBTW in opposite directions, with a significant main effect for weighting condition for the LyE variable in the medial-lateral direction. The small samples and no identification of impairments related to LyE at baseline were limitations of the study. The LyE may help differentiate subgroups who respond differently to BBTW. In both subgroups, LyE values moved toward the average of healthy

  14. The personification of animals: coding of human and nonhuman body parts based on posture and function.

    Science.gov (United States)

    Welsh, Timothy N; McDougall, Laura; Paulson, Stephanie

    2014-09-01

    The purpose of the present research was to determine how humans represent the bodies and limbs of nonhuman mammals based on anatomical and functional properties. To this end, participants completed a series of body-part compatibility tasks in which they responded with a thumb or foot response to the color of a stimulus (red or blue, respectively) presented on different limbs of several animals. Across the studies, this compatibility task was conducted with images of human and nonhuman animals (bears, cows, and monkeys) in bipedal or quadrupedal postures. The results revealed that the coding of the limbs of nonhuman animals is strongly influenced by the posture of the body, but not the functional capacity of the limb. Specifically, body-part compatibility effects were present for both human and nonhuman animals when the figures were in a bipedal posture, but were not present when the animals were in a quadrupedal stance (Experiments 1a-c). Experiments 2a and 2b revealed that the posture-based body-part compatibility effects were not simply a vertical spatial compatibility effect or due to a mismatch between the posture of the body in the image and the participant. These data indicate that nonhuman animals in a bipedal posture are coded with respect to the "human" body representation, whereas nonhuman animals in a quadrupedal posture are not mapped to the human body representation. Overall, these studies provide new insight into the processes through which humans understand, mimic, and learn from the actions of nonhuman animals. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. The effect of cognitive functional therapy in low back pain due to postural scoliosis: A randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Ahmed Mohamed Elshiwi

    2016-12-01

    Full Text Available Scoliosis is a lateral curvature of the spine and it is a common cause of back pain especially myofacial pain. Cognitive functional therapy is a novel challenges pain-related behaviors in a cognitively integrated, functionally manner. To study the effect of cognitive functional therapy in treatment of back pain due to postural scoliosis. Thirty Egyptian female patients were assigned randomly in to two equal groups. Patients in the control group received traditional therapeutic exercises (myofacial release, stretching and strengthening exercises of the back muscles, while patients in the experimental group received the same program of control group in addition to cognitive functional therapy. Each group received the program three sessions/week for six weeks. The severity of pain, functional disability, cobb's angle, and lumbar range of motion (flexion, extension, side bending to convex side of scoliosis were measured before and after 6 weeks of treatment. The statistical analysis revealed that there were there were significant reductions in pain level and functional disability and significant increase in ROM of trunk flexion and trunk extension and side bending between both groups (p < 0.05 in favor to study group. Conclusion: Supplementation of cognitive functional therapy in therapeutic exercise with myofacial release provided additional benefits with respect to pain, function disability, and lumbar range of motion (flexion, extension, and side bending in patients with back pain due to postural scoliosis after six weeks of treatment.

  16. Evaluation of postural control impairment using Balance Error Scoring System among athletes with ankle injury: an effective tool in daily clinical practice.

    Science.gov (United States)

    Vikram, M; Sundaraganesh, K; Justine, M; Kurup, M; Leonard, J H

    2012-01-01

    The main objective of the study was to investigate postural control impairment in athletes with history of ankle injury by using Balance Error Scoring System (BESS) and to compare with the controls. This is a case-control study that compared postural control among subjects with history of ankle injury with the matched controls. A total of sixty subjects (n = 60) were recruited from the department of physical education and sports science from a higher learning institute. Thirty athletes who had history of ankle injury were recruited for case group and the control group had an another thirty participants who were healthy athletes with no history of ankle injury. BESS was used to measure postural control by estimating the errors committed in standing between the two group of athletes. Independent sample t test was used to compare the means between two groups and the level of significance is set at level of 0.05. The athletes with history of ankle injury scored more number of errors in BESS with high mean value of (15.10 +/- 6.52 errors) than the control group (5.63 / 3.81 errors which was significant at p=0.01 level. Postural control impairment was identified among athletes with history of ankle injury when compared with control group.

  17. Ocular hypertension and posture.

    OpenAIRE

    Leonard, T J; Kerr Muir, M G; Kirkby, G R; Hitchings, R A

    1983-01-01

    Thirty-seven patients with ocular hypertension (OH) and 29 age matched controls were studied. Intraocular pressure (IOP) measurements were made in the sitting position and, immediately after changing posture, in the lying position. Sixty-three (85%) of the OH eyes and all the control eyes showed either stable IOP readings on changing posture of small elevations up to 3 mmHg. Eleven (15%) of the OH eyes showed larger elevations of IOP, between 5 and 9 mmHg when the patients changed to the lyin...

  18. Controle postural na síndrome de Pusher: influência dos canais semicirculares laterais Posture control in Pusher syndrome: influence of lateral semicircular canals

    Directory of Open Access Journals (Sweden)

    Taiza Elaine Grespan dos Santos Pontelli

    2005-08-01

    Full Text Available A síndrome de Pusher caracteriza-se por uma alteração do equilíbrio na qual pacientes com lesões encefálicas empurram-se em direção ao lado parético utilizando o membro não-afetado. O papel do sistema vestibular na alteração postural da síndrome de Pusher ainda não foi devidamente elucidado. OBJETIVO: Neste estudo objetivamos avaliar o papel dos canais semicirculares horizontais na expressão clínica da síndrome de Pusher, através da aplicação das provas calórica e rotatória. FORMA DE ESTUDO: Observacional, clínico e prospectivo. MATERIAL E MÉTODO: Avaliamos 9 pacientes com AVC e síndrome de Pusher internados na Enfermaria de Neurologia do HCFMRP-USP. Os pacientes foram submetidos à avaliação neurológica clínica e neuropsicológica, NIHSS, Scale for Contraversive Pushing - SCP, teste calórico e teste rotatório. RESULTADOS: Foram estudados 9 pacientes (5 homens com idade média de 71,8 ± 5,9 anos e com NIHSS médio de 18.33. Três pacientes apresentaram preponderância direcional contralateral à lesão encefálica na prova calórica. Na prova rotatória, foram observados quatro pacientes com preponderância direcional na análise de velocidade da componente lenta. CONCLUSÃO: Os resultados do presente estudo indicam que a disfunção do