Changes In Sway Research Articles

Preventing Acl Injuries With Martial Arts Break Falling Training

PURPOSE: ACL injuries have remained prevalent despite numerous prevention attempts. Most prevention has focused on traditional approaches. We propose a novel approach to injury prevention by implementing martial arts falling techniques. This training uses proprioceptive and kinesthetic conditioning to reinforce the athlete’s ability to mitigate at-risk postures. This study aims to evaluate the proprioceptive function and risk factors in soccer athletes that undergo fall training. METHODS: Members of a premier soccer club, ages 9 to 16, were recruited to. All subjects continued usual training. Subjects partook in the interventional training of martial arts fall training, taught by a 3rd degree black belt master in karate and aikido, twice weekly for ten weeks. Baseline and post-intervention, proprioceptive testing was performed using the Neurocom Balance Master. A linear mixed model was used to determine the effect of the intervention on variables of interest. The fixed effect was time point, used to compare pre to post intervention measures, and random effects included intercepts for subjects and trials within subjects. The level of significance was 0.05. RESULTS: A significant increase in movement time from pre to post (Premean=1.14, Postmean=1.94, p=.032), no significant change in turn time, turn sway, or sway energy. There was a non-significant decrease in impact index (Premean=46.3, Postmean=36.9, p=.206. A significant decrease in the mean impact index for the right lower extremity. While not statistically significant, downward trends were observed in right lower extremity for mean turn time, mean turn sway, and mean sway energy. Additionally, increases noted for mean equilibrium and mean strategy. CONCLUSIONS: Results of the mean impact index test highlight the efficacy of martial arts fall training in the dominant lower extremity. Furthermore, the trend of improvement in the dominant leg in a variety of proprioceptive metrics is noteworthy, suggesting the intervention reinforced the more honed neural pathways of the dominant side quicker than the non-dominant. Future research is needed to elucidate whether the non-dominant side can demonstrate the plasticity seen in the dominant side. Finally, the overall increase seen in mean equilibrium and mean strategy is promising.

Gender Differences in Postural Stability among 13-Year-Old Alpine Skiers.

This experiment examined changes in body sway after Wingate test (WAnT) in 19 adolescents practicing alpine skiing, subjected to the same type of training load for 4–5 years (10 girls and nine boys). The postural examinations were performed with eyes open (EO), eyes closed (EC), and sway reverenced vision (SRV) in the medial-lateral (ML) and anterior-posterior (AP) planes. The displacement of center of foot pressure (CoP), range of sway (RS), mean sway velocity (MV), way length, and surface area were measured in bipedal upright stance before and after the WAnT to assess the influence of fatigue on postural balance. There were no significant differences in WAnT parameters between girls and boys. Relative peak power (RPP), relative total work (RWtot) were (girls vs. boys) 8.89 ± 0.70 vs. 9.57 ± 1.22 W/kg, p < 0.05 and 227.91 ± 14.98 vs. 243.22 ± 30.24 W/kg, p < 0.05 respectively. The fatigue index (FI) was also on similar level in both genders; however, blood lactate concentration (BLa) was significantly higher in boys (10.35 ± 1.16 mM) than in girls (8.67 ± 1.35 mM) p = 0.007. In the EO examination, statistically significant differences between resting and fatigue conditions in the whole group and after the division into girls and boys were found. In fatigue conditions, significant gender differences were noted for measurements in the ML plane (sway path and RS) and RS in the AP plane. Comparison of the three conditions shows differences between EO vs. EC and SRV in AP plane measured parameters, and for RS in ML plane in rest condition in girls. The strong correlations between FI and CoP parameters mainly in ML plane in the whole group for all examination conditions were noted. By genders, mainly RS in ML plane strongly correlates with FI (r > 0.7). No correlation was found between BLa and CoP parameters (p > 0.06). The presented results indicate that subjecting adolescents of both genders to the same training may reduce gender differences in the postural balance ability at rest but not in fatigue conditions and that girls are significantly superior in postural balance in the ML plane than boys. It was also shown that too little or too much information may be destructive to postural balance in young adolescents.

Evaluation of postural balance in patients with obstructive sleep apnoea syndrome.

Patients with obstructive sleep apnoea syndrome (OSAS) can be more prone to accidents due to excessive daytime sleepiness which can lead to attention deficits and thereby cause balance problems. One of the tests evaluating postural balance is static posturography (SPG). In this study, we aimed to evaluate postural balance with SPG in OSAS patients. Patients who were referred to a sleep disorders outpatient clinic of a tertiary health care centre with snoring, daytime sleepiness or witnessed apnoea were enrolled consecutively in this cross-sectional study. They were grouped as the OSAS group and the control group according to the apnoea-hypopnoea index. Posturographic analyses were carried out in all subjects on a SPG platform under five different conditions: eyes open (EO), eyes closed (EC), head rotated to left (HL), head rotated to right (HR), and tandem Romberg. A total of 95 patients and 23 controls were included in the study. In EO conditions, there was no difference between the OSAS group and the control group in any of the posturographic parameters. In EC conditions, change in lateral sway was significantly higher in the OSAS group which also correlated negatively with SaO2(min). HR conditions caused an i ncrease in anterior-posterior (A-P) sway velocity, and HL conditions led to an increase in change in lateral and A-P sways, sway area, and sway area velocity in the OSAS group. Our findings suggest that postural balance in OSAS patients is impaired even in the very first hours of the day, and that the severity of the disease has an impact on postural balance.

Kinematic Validation of Postural Sway Measured by Biodex Biosway (Force Plate) and SWAY Balance (Accelerometer) Technology.

Background The Biodex Biosway® Balance System and SWAY Balance® Mobile smartphone application (SBMA) are portable instruments that assess balance function with force plate and accelerometer technology, respectively. The validity of these indirect clinical measures of postural sway merits investigation. Purpose The purpose of this study was to investigate the concurrent validity of standing postural sway measurements by using the portable Biosway and SBMA systems with kinematic measurements of the whole body Center of Mass (COM) derived from a gold-standard reference, a motion capture system. Study Design Cross-sectional; repeated measures. Methods Forty healthy young adults (21 female, 19 male) participated in this study. Participants performed 10 standing balance tasks that included combinations of standing on one or two legs, with eyes open or closed, on a firm surface or foam surface and voluntary rhythmic sway. Postural sway was measured simultaneously from SBMA, Biosway, and the motion capture system. The linear relationships between the measurements were analyzed. Results Significant correlations were found between Biosway and COM velocity for both progressively challenging single and double leg stances (τb = 0.3 to 0.5, p < 0.01 to <0.0001). SBMA scores and COM velocity were significantly correlated only for single leg stances (τb = −0.5 to −0.6, p < 0.0001). SBMA scores had near-maximal values with zero to near-zero variance in double leg stances, indicating a ceiling effect. Conclusion The force plate-based Biodex Biosway is valid for assessing standing postural sway for a wide range of test conditions and challenges to standing balance, whereas an accelerometer-based SWAY Balance smartphone application is valid for assessing postural sway in progressively challenging single leg stance but is not sensitive enough to detect lower-magnitude postural sway changes in progressively challenging double leg stances.

The Change in Sway and Neuromuscular Activity in Adult Degenerative Scoliosis Patients Pre and Post Surgery Compared With Controls.

Prospective cohort study. The purpose of this study is to quantify the extent of change in sway associated with maintaining a balanced posture within the cone of economy (CoE), in a group of adult degenerative scoliosis (ADS) patients' pre and postsurgery and compare them to matched non-scoliotic controls. Patients with spinal deformities adopt a variety of postural changes in the spine, pelvis, and lower extremities in their effort to compensate for the anterior shift in the gravity line. ADS patients are known to exhibit an increased sway within their CoE. Greater sway expends more energy while standing when compared with healthy controls. Spinal alignment surgery has been shown to improve sagittal vertical axis and balance. Thirty-three ADS patients and performed a series of functional balance tests a week before and 3 months after surgery along with 20 non-scoliotic control. ADS patients demonstrated more initial CoM (P = 0.001) and head (P = 0.011) displacements. Postoperatively ADS patients exhibited less CoM sway (P = 0.043) and head sway (P = 0.050), in comparison to their presurgery measures. Postsurgical ADS patients demonstrated more CoM (P = 0.002) and head (P = 0.012) displacements and increased muscle activity in comparison to non-scoliotic controls. Surgical alignment reduced the amount of sway, reduced the center of mass displacement, and reduced spine and lower extremity energy expenditure in ADS' patients. In symptomatic preoperative ADS patients, sagittal sway increased along with greater lumbar spine and lower extremity neuromuscular activity in comparison to a non-scoliotic control. Although surgical alignment improved ADS functional parameters during a dynamic balance test, these parameters approached but did not fully achieve non-scoliotic control parameters when measured 3 months after surgery. 3.

Monitoring of postural sway with a head-mounted wearable device: effects of gender, participant state, and concussion.

Objective: To assess the utility of a head-mounted wearable inertial motion unit (IMU)-based sensor and 3 proposed measures of postural sway to detect outliers in athletic populations at risk of balance impairments.Methods: Descriptive statistics are used to define a normative reference range of postural sway (eyes open and eyes closed) in a cross-sectional sample of 347 college students using a wireless head-mounted IMU-based sensor. Three measures of postural sway were derived: linear sway power, eyes closed vs eyes open sway power ratio (Ec/Eo ratio), and weight-bearing asymmetry (L-R ratio), and confidence intervals for these measures were calculated. Questionnaires were used to identify potentially confounding state variables. A prospective study of postural sway changes in 47 professional, college, and high school athletes was then carried out in on-field settings to provide estimates of session-to-session variability and the influence of routine physical activity on sway measures. Finally, pre-post-injury changes in sway are measured for a participant who was diagnosed with a concussion.Results: Despite the heterogenous population and sampling environments, well-defined confidence intervals were established for all 3 sway measures. Men demonstrated significantly greater sway than women. Two state variables significantly increased sway: the use of nicotine and prescription medications. In the athletes, session-to-session variability and changes due to routine physical activity remained well within 95% confidence intervals defined by the cross-sectional sample for all 3 sway measures. The increase in sway power following a diagnosed concussion was more than an order of magnitude greater than the increases due to session-to-session variability, physical activity, or other participant state variables.Conclusion: The proposed postural sway measures and head-mounted wearable sensor demonstrate analytic utility for on-field detection of abnormal sway that could be potentially useful when making remove-from-activity and return-to-activity decisions for athletes at risk of impact-induced balance impairments.

Exploratory analyses on racial differences in diurnal cortisol and risk-taking behavior in gambling disorder

Patients affected by functional (psychogenic) movement disorders (FMD) have abnormal processing of stress responses. However, little is known about the influence of this abnormal stress processing on automatic motor defense behavior, such as freeze response. Our aim was thus to investigate stress-induced postural motor responses in FMD.Nine FMD patients and thirteen healthy controls were engaged in the Trier Social Stress Test, while we measured the movement of their body by means of accelerometers and gyroscopes attached to the thorax. Standard deviation of thorax acceleration, reflecting the variability of movement amplitude (body sway), was compared across groups over time in a 2 × 2 ANOVA design. Higuchi’s fractal dimension (HFD), reflecting the complexity of movement pattern over time, was also analyzed. Salivary cortisol and α-amylase samples were collected before and after the experiment, as stress biomarkers. Pearson’s correlation coefficients were calculated between these biomarkers and movement parameters.A significant interaction effect was found, showing that healthy controls reduced their thorax sway over time during exposure to stress (from 0.027 ± 0.010 m/s2 to 0.023 ± 0.008 m/s2, effect size of Cohen’s d = 0.95), whereas patients with FMD did not. This change in body sway in controls over time negatively correlated with salivary cortisol values (ρ = –0.67, p = 0.012). A significant group effect revealed that FMD patients had an overall larger body sway (0.038 ± 0.013 m/s2) compared to controls (0.025 ± 0.009 m/s2 – effect size of Cohen’s d = 1.29) and a lower HFD (1.602 ± 0.071) than controls (1.710 ± 0.078 – Cohen’s d = 1.43).Patients with FMD failed to show a reduction of body sway over time, i.e., freeze response observed in the controls, thus suggesting an impairment in the automatic defense behavior. Moreover, our analysis found a lower complexity of movement (HFD) in FMD, which deserves future research in order to verify whether this could represent a characteristic trait of the disorder.

Postural sway changes during static standing with concurrent task in children with traumatic brain injury.

Objectives:To investigate the effects of concurrent tasks (motor and cognitive) on postural control performance in children with traumatic brain injury (TBI) compared to typically developing (TD) control subjects.Methods:Sixteen children with TBI (aged 11.63±1.89 years) and 22 TD controls (aged 11.41±2.24 years) participated in this case-control study. This study was conducted between May 2016 and March 2017. Each child performed static standing under 3 different conditions: single, concurrent motor, and concurrent cognitive task. Postural control performance measure includes sway area, anterior-posterior (AP) sway velocity, medio-lateral (ML) sway velocity, AP sway distance and ML sway distance as measured using the APDM® Mobility Lab (Oregon, Portland). A repeated-measure analysis of variance was used to analyse the data.Results:We found that children with TBI showed significantly more deterioration in postural control performance than TD children (p<0.05). Both concurrent tasks (motor and cognitive) significantly decreased postural control performance in both groups with more pronounced changes in children with TBI than that of the TD controls.Conclusion:The results demonstrated that, performing concurrent tasks (motor and cognitive) during upright standing resulted in deterioration of postural control performance. The existence of cognitive and balance impairment in children with TBI will possibly cause concurrent tasks to be more complex and demands greater attention compared to single task.

Analysis of Rope Sway during Travel of Elevator

An elevator for a high-rise building ought to perform emergency operation when the elevator rope is oscillated by the sway of the building caused by wind force or long – period ground motion. In recent years, techniques for directly measuring rope amplitude in real time have been utilized. Thereby, it has become possible to perform apposite emergency operation based on the rope sway condition. On the other hand, the rope sway changes continuously every moment during the travel of elevator. Therefore, it is very important to grasp the changing tendency of rope sway for the efficient judgment of emergency operation. In this research, we constructed a simulation model which quantitatively simulates the rope sway motion during a travel of an elevator.

Abnormal postural behavior in patients with functional movement disorders during exposure to stress

BackgroundPatients affected by functional (psychogenic) movement disorders (FMD) have abnormal processing of stress responses. However, little is known about the influence of this abnormal stress processing on automatic motor defense behavior, such as freeze response. Our aim was thus to investigate stress-induced postural motor responses in FMD. MethodsNine FMD patients and thirteen healthy controls were engaged in the Trier Social Stress Test, while we measured the movement of their body by means of accelerometers and gyroscopes attached to the thorax. Standard deviation of thorax acceleration, reflecting the variability of movement amplitude (body sway), was compared across groups over time in a 2 × 2 ANOVA design. Higuchi’s fractal dimension (HFD), reflecting the complexity of movement pattern over time, was also analyzed. Salivary cortisol and α-amylase samples were collected before and after the experiment, as stress biomarkers. Pearson’s correlation coefficients were calculated between these biomarkers and movement parameters. ResultsA significant interaction effect was found, showing that healthy controls reduced their thorax sway over time during exposure to stress (from 0.027 ± 0.010 m/s2 to 0.023 ± 0.008 m/s2, effect size of Cohen’s d = 0.95), whereas patients with FMD did not. This change in body sway in controls over time negatively correlated with salivary cortisol values (ρ = –0.67, p = 0.012). A significant group effect revealed that FMD patients had an overall larger body sway (0.038 ± 0.013 m/s2) compared to controls (0.025 ± 0.009 m/s2 – effect size of Cohen’s d = 1.29) and a lower HFD (1.602 ± 0.071) than controls (1.710 ± 0.078 – Cohen’s d = 1.43). ConclusionsPatients with FMD failed to show a reduction of body sway over time, i.e., freeze response observed in the controls, thus suggesting an impairment in the automatic defense behavior. Moreover, our analysis found a lower complexity of movement (HFD) in FMD, which deserves future research in order to verify whether this could represent a characteristic trait of the disorder.

Changes in trunk sway and impairment during sitting and standing in children with cerebral palsy.

Poor postural control constitutes a major impairment in children with cerebral palsy (CP), compromising everyday activities such as sitting- and standing-position. In this study, we measured trunk sway during sitting- and standing-position. Additionally, we assessed trunk control ability using the trunk impairment scale (TIS), trunk control measurement scale (TCMS), and sitting assessment test for children with neuromotor dysfunction (SACND), in children with CP. Fifteen children (10 boys and 5 girls) were recruited for this study. Trunk sway was measured using a triaxial accelerometer that recorded variation in movement acceleration during quiet sitting- and standing-position. Anterior-posterior (AP) acceleration was significantly greater in the standing position than the sitting position (p= 0.001). Medio-lateral (ML) acceleration was significantly greater in the standing position than in the sitting position (p= 0.012). The TIS total score showed a moderate negative relationship with AP acceleration (r=-0.635, p= 0.011). The TCMS total score moderately and negatively correlated with AP acceleration (r=-0.582, p= 0.023). The SACND total score moderately and positively correlated with AP acceleration (r= 0.670, p= 0.006). Measurement of trunk sway using a triaxial accelerometer revealed a moderate correlation with trunk control test data and excellent reliability. Our findings suggest that measurement of trunk sway using a triaxial accelerometer is not time-consuming, and is simple and easy. Our approach can be applied in clinical settings to gain information on trunk control in children with CP.

Postural threat influences the conscious perception of body position during voluntary leaning

BackgroundHeight-related changes in postural control can alter feedback used to control balance, which may lead to a mismatch in perceived and actual sway changes during quiet stance. However, there is still a need to examine how these changes affect the ability to detect limits of stability (and movements related to base of support limits). Research questionThe aim of this study was to examine how changes in height-related threat influence conscious perceptions of body position during voluntary balance tasks. MethodsTwenty young healthy adults, fitted with kinematic markers on the right side of the body, stood on a forceplate mounted to a hydraulic lift placed at two heights (0.8 m and 3.2 m). At height (completed first), participants leaned as far forward as possible, at the ankle joint, while trying to remain as an inverted pendulum. Then, at each height, participants stood with eyes open, and voluntarily leaned to one of ten targets (10%–100% maximum lean) displayed visually as angular displacement of body segments on a screen. Once on target, participants reported a perceived position relative to their maximum lean. Balance confidence, fear and anxiety, and physiological arousal (hand electrodermal activity, EDA) were recorded and statistically tested using paired sample t-tests. Actual and perceived body positions were tested using repeated measures ANOVAs (height x target). ResultsHeight significantly increased EDA, fear and anxiety, and decreased balance confidence. Participants voluntarily leaned to all target positions equally across heights. However, at any given target position, the perceived lean changed with height. When participants are asked to lean to a target in at height, their amount of perceived lean was larger by 4.9%, on average (range: 1.8%–9.7%). SignificanceThis modulation in perceived limits of stability may increase the risk of falls in those who have an increased fear of falling.

Studying Relationship Between Static and Dynamic Balance Indices and Knee Pain Severity in Patients with Knee Osteoarthritis

Background and Objectives: One of the predisposing factors for postural sway changes in patients with knee osteoarthritis is the severity of knee pain. Therefore, the purpose of this study was to evaluate the relationship between pain severity and static and dynamic balance indices in patients with knee osteoarthritis.Materials and Methods: 15 patients with knee osteoarthritis were selected through simple non-probability sampling. Static and dynamic balance indices were also measured by Biodex system, the pain severity by the Visual Analogue Scale (VAS) in two pre and post time intervals. The treatment was performed for the balance trainings group for 3 weeks and 5 times per week. Paired statistical t-test and Pearson test were used to analyze the data.Results: The results showed that balance trainings resulted in significant improvement in pain severity and dynamic and static balance indices. There was a significant direct correlation between pain severity and anterior-posterior stability index and medial-lateral stability index on two feet with the closed eyes with exercise, respectively (rho = 0.52, p = 0.04) and (rho = 0.53, p = 0.03). There was also a significant indirect correlation between pain severity and anterior-posterior stability index on the affected leg with the closed eyes (rho = 0.60, p = 0.01).Conclusion: The results of the study confirm the direct and indirect relationship between dynamic balance indices and pain intensity; in the future studies the effect of pain on neuromuscular factors should be considered.

Proprioceptive impairments in high fall risk older adults: the effect of mechanical calf vibration on postural balance

BackgroundImpairments in proprioceptive mechanism with aging has been observed and associated with fall risk. The purpose of the current study was to assess proprioceptive deficits among high fall risk individuals in comparison with healthy participants, when postural performance was disturbed using low-frequency mechanical gastrocnemius vibratory stimulation.MethodsThree groups of participants were recruited: healthy young (n = 10; age = 23 ± 2 years), healthy elders (n = 10; age = 73 ± 3 years), and high fall risk elders (n = 10; age = 84 ± 9 years). Eyes-open and eyes-closed upright standing balance performance was measured with no vibration, and 30 and 40 Hz vibration of both calves. Vibration-induced changes in balance behaviors, compared to baseline (no vibratory stimulation) were compared between three groups using multivariable repeated measures analysis of variance models.ResultsOverall, similar results were observed for two vibration frequencies. However, changes in body sway due to vibration were more obvious within the eyes-closed condition, and in the medial–lateral direction. Within the eyes-closed condition high fall risk participants showed 83% less vibration-induced change in medial–lateral body sway, and 58% less sway velocity, when compared to healthy participants (p < 0.001; effect size = 0.45–0.64).ConclusionsThe observed differences in vibration effects on balance performance may be explained by reduced sensitivity in peripheral nervous system among older adults with impaired balance.

Age-related Changes in Postural Sway During Sit-to-stand in Typical Children and Children with Cerebral Palsy

ABSTRACTObjective: To assess age-related changes in postural sway during sit-to-stand (STS) in typical children (TC) and children with mild cerebral palsy (CP). Methods: Thirty-five TC and 23 children with mild CP were allocated in four different age groups: 5–6, 7–9, 10–12, and 13–15 years; they all performed STS movements over a force plate. Anterior-posterior and medial-lateral amplitude of center of pressure (CoP) displacement, area and velocity of CoP sway were analyzed and compared between the age groups for TC and children with CP. Results: TC at 5 to 6 years of age showed higher values of anterior-posterior CoP displacement and Area of CoP sway than at 10–12 years, during the stabilization phase. There were no age-related changes for CP. Conclusion: TC change their postural sway during the last STS phase over the years, reducing their body sway. Children with CP did not show age-related changes in sway during STS, reflecting a distinct rhythm of postural control development in this population.

Validity and Reliability of a Portable Balance Tracking System, BTrackS, in Older Adults.

Falls are the leading cause of disability, injury, hospital admission, and injury-related death among older adults. Balance limitations have consistently been identified as predictors of falls and increased fall risk. Field measures of balance are limited by issues of subjectivity, ceiling effects, and low sensitivity to change. The gold standard for measuring balance is the force plate; however, its field use is untenable due to high cost and lack of portability. Thus, a critical need is observed for valid objective field measures of balance to accurately assess balance and identify limitations over time. The purpose of this study was to examine the concurrent validity and 3-day test-retest reliability of Balance Tracking System (BTrackS) in community-dwelling older adults. Minimal detectable change values were also calculated to reflect changes in balance beyond measurement error. Postural sway data were collected from community-dwelling older adults (N = 49, mean [SD] age = 71.3 [7.3] years) with a force plate and BTrackS in multitrial eyes open (EO) and eyes closed (EC) static balance conditions. Force sensors transmitted BTrackS data via a USB to a computer running custom software. Three approaches to concurrent validity were taken including calculation of Pearson product moment correlation coefficients, repeated-measures ANOVAs, and Bland-Altman plots. Three-day test-retest reliability of BTrackS was examined in a second sample of 47 community-dwelling older adults (mean [SD] age = 75.8 [7.7] years) using intraclass correlation coefficients and MDC values at 95% CI (MDC95) were calculated. BTrackS demonstrated good validity using Pearson product moment correlations (r > 0.90). Repeated-measures ANOVA and Bland-Altman plots indicated some BTrackS bias with center of pressure (COP) values higher than FP COP values in the EO (mean [SD] bias = 4.0 [6.8]) and EC (mean [SD] bias = 9.6 [12.3]) conditions. Test-retest reliability using intraclass correlation coefficients (ICC2.1 was excellent (0.83) and calculated MDC95 for EO (9.6 cm) and EC (19.4 cm) and suggested that postural sway changes of these amounts are meaningful. BTrackS showed some bias with values exceeding force plate values in both EO and EC conditions. Excellent test-retest reliability and resulting MDC95 values indicated that BTrackS has the potential to identify meaningful changes in balance that may warrant intervention. BTrackS is an objective measure of balance that can be used to monitor balance in community-dwelling older adults over time. It can reliably identify changes that may require further attention (eg, fall-prevention strategies, declines in physical function) and shows promise for assessing intervention efficacy in this growing segment of the population.

The effects of plantar perception training on balance and falls efficacy of the elderly with a history of falls: A single-blind, randomized controlled trial

PurposeThe purpose of this study was to identify the effects of plantar perception training using a hardness discrimination task on balance and falls efficacy of the elderly who have experienced a fall. Materials and methodsSixty-two elderly persons 65 years of age or older were randomly allocated to the experimental group (n = 31) or the control group (n = 31). The experimental group performed a hardness discrimination task using five different levels of hardness of sponge mats, while the control group performed the same task except that they were not asked to discriminate hardness levels of sponge mats. All subjects performed 10 sessions for two weeks. Outcome measures were conducted using center of pressure (CoP) sway in the standing position, the Timed Up and Go (TUG) test, and falls efficacy scale (FES) to measure balance and falls efficacy. ResultsThere were no significant differences in general characteristics between both groups (p > .05). After 10 sessions, plantar perception was significantly improved in the experimental group (F = 101.18, p < .001). Additionally, changes in CoP sway with eye closed and TUG test were significantly different (p < .05) between the experimental group (CoP sway with eye closed, −208.32 ± 74.89; TUG test, −1.91 ± 0.72) and the control group (CoP sway with eye closed, −14.55 ± 35.44; TUG test, −1.31 ± 0.75). ConclusionsThese results showed that plantar perception training might be beneficial to improve falls efficacy as well as balance of the elderly.

Age-related Changes in Body Sway When Standing with Eyes Closed or Open and on Stable and Unstable Surfaces

This study examined how the amount of body sway various by age when people are standing on either a stable or an unstable surface with eyes either open or closed. The participants were 83 healthy women ranging in age from their teens to their eighties (with 9 to 12 women in each of the eight 10-year cohorts). Body sway was measured for 60 s while the participants were standing on a force plate with foam rubber (stable posture) or without form rubber (unstable posture). Path length (in cm), envelopment area (in cm2), and the ratio between these two measures were selected as evaluation parameters. In a three-way analysis of visual, posture, and age factors, path length, and envelopment area showed a significant interaction. Path length was shorter with the rubber than without it for all age levels with the eyes open or closed. An age-level difference was found only when the eyes were open. The envelopment area was smaller with than without the rubber with the eyes open for all age levels except women in their thirties and for all age groups with the eyes closed. Again, a significant age-level difference was found only with the eyes open. The ratio of length to envelopment area demonstrated a significant main effect for factors of both posture and age level. It was greater without than with the foam rubber with the eyes open for all age levels except women from their twenties to their forties, and for all age levels with the eyes closed. Coefficients in the linear regression equations, calculated based on the means for each age level, were significant in for three parameters. Values of path length and envelopment area were smaller without than with the rubber, but no significant differences were found between these values with the eyes open and closed. In conclusion, body sway in all age levels is greater on a less stable surface and increases with age, but the effect of vision on body sway can be disregarded.

Haptic Cues for Balance: Use of a Cane Provides Immediate Body Stabilization.

Haptic cues are important for balance. Knowledge of the temporal features of their effect may be crucial for the design of neural prostheses. Touching a stable surface with a fingertip reduces body sway in standing subjects eyes closed (EC), and removal of haptic cue reinstates a large sway pattern. Changes in sway occur rapidly on changing haptic conditions. Here, we describe the effects and time-course of stabilization produced by a haptic cue derived from a walking cane. We intended to confirm that cane use reduces body sway, to evaluate the effect of vision on stabilization by a cane, and to estimate the delay of the changes in body sway after addition and withdrawal of haptic input. Seventeen healthy young subjects stood in tandem position on a force platform, with eyes closed or open (EO). They gently lowered the cane onto and lifted it from a second force platform. Sixty trials per direction of haptic shift (Touch → NoTouch, T-NT; NoTouch → Touch, NT-T) and visual condition (EC-EO) were acquired. Traces of Center of foot Pressure (CoP) and the force exerted by cane were filtered, rectified, and averaged. The position in space of a reflective marker positioned on the cane tip was also acquired by an optoelectronic device. Cross-correlation (CC) analysis was performed between traces of cane tip and CoP displacement. Latencies of changes in CoP oscillation in the frontal plane EC following the T-NT and NT-T haptic shift were statistically estimated. The CoP oscillations were larger in EC than EO under both T and NT (p < 0.001) and larger during NT than T conditions (p < 0.001). Haptic-induced effect under EC (Romberg quotient NT/T ~ 1.2) was less effective than that of vision under NT condition (EC/EO ~ 1.5) (p < 0.001). With EO cane had little effect. Cane displacement lagged CoP displacement under both EC and EO. Latencies to changes in CoP oscillations were longer after addition (NT-T, about 1.6 s) than withdrawal (T-NT, about 0.9 s) of haptic input (p < 0.001). These latencies were similar to those occurring on fingertip touch, as previously shown. Overall, data speak in favor of substantial equivalence of the haptic information derived from both “direct” fingertip contact and “indirect” contact with the floor mediated by the cane. Cane, finger and visual inputs would be similarly integrated in the same neural centers for balance control. Haptic input from a walking aid and its processing time should be considered when designing prostheses for locomotion.

Quantitative Romberg's test in acute carbon monoxide poisoning treated by hyperbaric oxygen.

The aim of this study was to evaluate whether monitoring of acute carbon monoxide-poisoned (COP) patients by means of quantitative Romberg's test (QR-test) during a hyperbaric oxygen (HBO₂) therapy regimen could be a useful supplement in the evaluation of neurological status. We conducted a retrospective study (2000-2014) in which we evaluated data containing quantitative sway measurements of acute COP patients (n = 58) treated in an HBO₂ regimen. Each patient was tested using QR-test before and after each HBO₂ treatment. Data were analyzed using linear mixed models (LMM). In each LMM, sway prior to HBO₂ therapy was set as the fixed effect and change in sway after HBO₂ therapy was set as the response variable. Patient, treatment number, weight and age were set as random effects for all LMMs. From the LMMs we found that larger values of sway prior to HBO₂ produced a negative change in sway. We found no correlation between CO level and sway (P=0.1028; P=0.8764; P=0.4749; P=0.5883). Results showed that loss of visual input caused a significant increase in mean sway (P=0.028) and sway velocity (P⟨0.0001). The Quantitative Romberg's test is a fast, useful supplement to neurological evaluation and a potential valuable tool for monitoring postural stability during the course of treatment in acute COP patients.