Relation between the Sensory and Anthropometric Variables in the Quiet Standing Postural Control: Is the Inverted Pendulum Important for the Static Balance Control?

Quantitative evaluation of postural balance utilizing pressure plate: Findings from 1526 healthy Chinese individuals aged 20-80

BACKGROUND

The ability to maintain postural balance is essential for daily activities and is often assessed by measuring postural sway using pressure plates. However, there is a lack of large-sample studies evaluating balance in healthy populations.

RESEARCH QUESTION

What are the normative data on postural balance in healthy Chinese individuals, and how do age, sex, height, weight, and body mass index (BMI) correlate with postural balance parameters?

METHODS

A cross-sectional study was conducted with 1526 healthy individuals aged 20-80 years. Postural balance was evaluated using a pressure plate, and 14 center of pressure (COP) parameters were recorded. All COP parameter results were normalized based on foot area (foot length × bipedal width). Statistical analyses assessed correlations and percentiles.

RESULTS

Balance were consistently greater for males than for females across all ages and eye conditions. The difference became statistically significant for both males and females after 40-49 years. Balance began to deteriorate for males in the 40-49 age group, while for females, deterioration began in the 50-59 age group. Anthropometric parameters, including height, weight, and BMI, demonstrated weak or no correlation with COP parameters. The closed-eye condition consistently showed significantly greater COP values than the open-eye condition.

SIGNIFICANCE

This study provides comprehensive normative data on COP parameters, offering a valuable reference for quantitative assessment of postural balance. Notably, balance ability declines with age in both males and females, but declines earlier in males, with females consistently demonstrating better balance across age groups. These insights into age- and sex-related differences in balance may support targeted interventions to enhance postural stability in Chinese adults.

Reference values for static posturography of sportive and healthy adults aged 18-30 years

BACKGROUND

Measuring postural sway and comparing results in a pre-post design or with reference values can increase diagnostic accuracy and the quality of certain treatments and rehabilitation. The process of continuously regulating and sustaining a stable posture involves intricate sensorimotor control.

METHODS

All 173 participants (78♂, 95♀; 21.9 ± 2.7 years, 172.6 ± 9.8 cm; 70.0 ± 13.3 kg; BMI: 22.7 ± 2.8) were students in sport and health sciences. Static posturography (open eyes, closed eyes) was performed for 30 s under standardized conditions on a force plate and the parameters analyzed were the sway path length (SPL) and the area of ellipse (AoE).

RESULTS

On average, with eyes open the SPL was 250 ± 116 mm, and the AoE was 125 ± 82 mm2 measured with eyes open. With eyes closed, the SPL increased to 337 ± 151 mm and the AoE increased to 175 ± 125 mm2. An examination of possible sex differences in static balance revealed only a significant difference for the AoE with closed eyes. In general women achieved slightly better scores than men did. Body height did not have an influence on balance.

CONCLUSION

The present dataset provides reference values for young and sportive adults between 18 and 30 years of age. An examination of possible gender differences in static balance revealed a significant difference only between men and women for AoE with closed eyes. Body height does not have an influence on balance but the literature is inconsistent and further research is needed. Owing to the popular use of posturography in practice, further reference values are needed, and more attention should be given to ΔSPL and ΔAoE (open eyes, closed eyes) as well as the interpretation of the relationship between the SPL and AoE.

Importance of muscle strength to maintain mobility, but not to maintain postural balance in older women: Cross-sectional study

BACKGROUND

Acknowledging the relationship between postural control and muscle strength in lower limbs is important to find persons with high fall risk and to design fall prevention exercise programs.

OBJECTIVE

To investigate the connection between knee muscle strength, semi-static postural balance, and functional mobility in irregularly active older women.

METHODS

One hundred and ten older women aged 60 to 85 years underwent a semi-static postural balance test in a force and functional mobility measured by Timed Up & Go (TUG) with and without Cognitive Tasks (CT). Muscle strength of the knee was assessed by isokinetic dynamometry at 60°/s.

RESULTS

A negative correlation between the functional mobility (TUG with and without CT) and the muscular strength of the knee was observed. Regarding semi-static balance, there was a low negative correlation with peak torque corrected for body weight of the extensors with the following variables with eyes open: Mean Velocity Dominant limb (D) (r = -0.19; p = 0.03); and anteroposterior range Non-Dominant limb (ND) (r = -0.19; p = 0.04); with eyes closed: mediolateral range ND limb (r = -0.21; p = 0.02) and Mean Velocity ND limb (r = -0.18; p = 0.05).

CONCLUSIONS

This study found that better functional mobility was associated with greater muscle strength in the knee in elderly women. There were weak negative correlations between knee extensor strength and some measures of semi-static postural balance, suggesting that different motor control actions are required to maintain semi-static balance and mobility. In the case of semi-static balance, a lower level of muscle response is required than in functional mobility.

Differences in pre-season balance among student athletes based on level of contact, age, and sex

BACKGROUND

Assessing postural control is important for the assessment of motor function after concussion. Data used for postural control assessment typically do not take the sport played, age, or sex of the athlete into consideration. It is plausible these variables may be significant when making return-to-play decisions.

RESEARCH QUESTION

This study used the BTrackS database to examine differences in postural control in athletes playing different types of sports and across sex and age.

METHODS

BTrackS data from 9093 high school to college-aged athletes (aged 14-22 years) were examined employing a One-way ANOVA with a post-hoc test to compare CoP path length between sport types. A moderation analysis was used to test interaction effects of sex and age on a CoP/BMI ratio.

RESULTS

Significant differences were observed between sport types, F(3,9089) = 42.4, p <.001, η2 = 0.014. Post hoc tests indicated that collision (M = 25.0, SD = 7.6) sport athletes exhibited significantly higher CoP measures compared to the contact (M = 23.4, SD = 7.4), limited contact (M = 22.9, SD = 6.9), and non-contact (M = 23.0, SD = 7.4) athletes. There was no difference between other sport types (p >.20). A significant mean sex difference (Mmale = 0.924, Mfemale = 0.898, p <.001) and a quadratic association with age, (β = -0.042, p <.001) was observed. Further, magnitude of those age differences decreased with age (β = 0.011, p <.001). An interaction of age and sex was significant for linear (β = 0.020, p <.001) and quadratic terms (β = -0.006, p <.001).

SIGNIFICANCE

Athletes exhibited different postural control when the type of sport, age, and sex was taken into consideration. This data possess clinical significance as this suggests that normative postural control data for collision sport athletes should be derived from data based upon type of sport played, age, and sex of the athlete.

Factors Affecting Balance Performance in Adolescents

(1) Background: The influence of different factors on balance in adolescence is assessed by conducting functional balance tests that examine its different components. (2) Materials and methods: The study sample comprised 110 healthy adolescents of both sexes, aged 12-18 years. Single Leg Stance with Eyes Open (SLS-EO) and Eyes Closed (SLS-EC) tests were conducted to evaluate static balance, whereas the Functional Reach Test (FRT) and Lateral Reach Test (LRT) were performed to establish functional stability limits. The influence of sex, age, demographic factors, anthropometric characteristics, participation in sports activities, and trunk extensor muscle endurance (Biering-Sorensen test) on balance performance was determined through correlational and univariate linear regression analyses. (3) Results: Older age (Beta [β] = 0.247; 95% CI [0.75, 5.20]; p < 0.01) and better trunk extensor muscle endurance (β = 0.224; 95% CI [0.015, 0.13]; p < 0.05) were significant predictors of the SLS-EO results, while younger age (β = -0.219; 95% CI [-1.32, -0.11]; p < 0.05) and higher muscle percentage (β = 0.237; 95% CI [0.06, 0.48]; p < 0.05) emerged as significant predictors of LRT performance, and greater bone mass was a significant predictor of FRT results (β = 0.444; 95% CI [3.62, 8.17]; p < 0.01). However, none of the independent variables was a statistically significant predictor of the SLS-EC results. (4) Conclusions: The current study found that age, trunk extensor muscle endurance, muscle percentage, and bone mass are significant predictors of different balance components, suggesting that balance is task-specific.

The effect of surgical repair of the chest on postural stability among patients with pectus excavatum

Pectus excavatum is the most encountered of chest wall deformities. It may produce respiratory and cardiovascular symptoms, hence surgical repair of this defect is performed. The procedure involving the insertion of metal bars under the sternum (the Nuss procedure) usually brings significant improvement to patients. However, the effect of the repair on the postural stability of patients has not been studied so far. To investigate the problem of patients' stability in the postoperative period male patients with pectus excavatum (n = 21) and healthy controls (n = 22) were included in the study. Using posturography methods, we showed a negative impact of the pectus excavatum repair surgery on patients' postural stability in the first postoperative phase. The centre of pressure displacement parameters used to measure postural stability were lower after the repair for both, the frontal and sagittal plane as well as for the velocity of displacements in the sagittal plane in the double stance with eyes open. Poorer postural stability was also found in patients with pectus excavatum when compared to healthy controls. Our findings may be useful for functional monitoring in the evaluation and surgical management of pectus excavatum patients and also when designing the rehabilitation of patients undergoing the Nuss procedure.

Vergleichende Untersuchung der posturalen Kontrolle bei 20–40-Jährigen und Karate-Kaderathleten mittels eines neuromuskulären Trainingsgerätes

Hintergrund Die posturale Kontrolle dient dem Erhalt der aufrechten Körperhaltung und trägt zur Gleichgewichtsregulation bei. Die im höheren Alter zunehmenden neuromuskulären Defizite führen zu einer Verschlechterung der posturalen Kontrolle, die durch neuromuskuläres Training verbessert werden kann. In der Annahme, dass neuromuskuläre Defizite bereits früh auftreten, wurden die posturalen Fähigkeiten von 20–40-Jährigen untersucht. Zudem wurde der Einfluss von Leistungssport auf die posturale Kontrolle durch die Untersuchung von Karate-Kaderathleten geprüft.

Methodik Für einen Altersvergleich wurden 123 altershomogene Gesunde zwischen 20 und 40 Jahren untersucht. 24 Karate-Kaderathleten wurden mit den 20–25-jährigen Gesunden der „Normalbevölkerung“ verglichen. Zur Datenerhebung wurde ein neuromuskuläres Trainingsgerät, der Human Body Equilibrium 360 (Huber 360), verwendet.

Ergebnisse Im Altersvergleich zeigten sich für alle 7 Messungen keine signifikanten Unterschiede. Die Probanden waren zu jung, um Defizite zu erkennen. Jedoch zeigten sich einige allgemeine Erkenntnisse. Im beidbeinigen Stand war bei allen Gruppen eine signifikante Zunahme der Körperschwerpunkt (KSP) -Schwankungen nach Augenschluss zu sehen. Der Einfluss der Füßigkeit bzw. Händigkeit zeigte sich im Einbeinstand und Krafttest. Geschlechtsspezifische Unterschiede waren zu verzeichnen. Bei der Untersuchung der Karate-Kaderathleten zeigten sich verschiedene trainingsspezifische Anpassungen. So konnten Karatesportler den Wegfall der visuellen Information besser kompensieren. Karatesportler wiesen außerdem ein signifikant breiteres Gangbild und ein größeres Stabilitätsareal auf. Sportler konnten ihren KSP weiter verlagern, ohne aus dem Gleichgewicht zu geraten.

Diskussion Der Huber 360 ist als Rehabilitations- und Trainingsgerät aufgrund der geringen Trennschärfe der Tests in seinem gesamten Anwendungsspektrum nur bedingt geeignet, da signifikante Unterschiede zwischen den Gruppen schwer zu detektieren sind. Einzelne trainingsspezifische Anpassungen durch leistungsorientiertes Karatetraining sind erkennbar und unterstreichen den Einfluss des Trainings auf die posturale Kontrolle. Zusammenfassend lässt sich sagen, dass die Anwendung des Huber 360 zur Beurteilung von posturalen Fähigkeiten im Altersvergleich und bei Unterscheidung trainingsspezifischer Anpassungen einen differenzierten und selektiveren Einsatz der einzelnen Tests bedarf. Weitere Untersuchungen mit älteren Patienten mit unterschiedlichen Erkrankungen sind geplant.

Balance and Posture in Children and Adolescents: A Cross-Sectional Study

Balance and posture are two topics that have been extensively studied, although with some conflicting findings. Therefore, the aim of this work is to analyze the relationship between the postural angles of the spine in the sagittal plane and the stable static balance. A cross-sectional study was conducted with children and adolescents from schools in northern Portugal in 2019. An online questionnaire was used to characterize the sample and analyze back pain. Spinal postural angle assessment (pelvic, lumbar, and thoracic) was performed using the Spinal Mouse^®, while stabilometry assessment was performed using Namrol^® Podoprint^®. Statistical significance was set as α = 0.05. The results showed that girls have better balance variables. There is a weak correlation between the anthropometric variables with stabilometry variables and the postural angles. This correlation is mostly negative, except for the thoracic spine with anthropometric variables and the lumbar spine with BMI. The results showed that postural angles of the spine are poor predictors of the stabilometric variables. Concerning back pain, increasing the postural angle of the thoracic spine increases the odds ratio of manifestation of back pain by 3%.

Inter-Individual Variability in Postural Control During External Center of Mass Stabilization

Understanding the relation between the motion of the center of mass (COM) and the center of pressure (COP) is important to understand the underlying mechanisms of maintaining body equilibrium. One way to investigate this is to stabilize COM by fixing the joints of the human and looking at the corresponding COP reactions. However, this approach constrains the natural motion of the human. To avoid this shortcoming, we stabilized COM without constraining the joint movements by using an external stabilization method based on inverted cart-pendulum system. Interestingly, this method only stabilized COM of a subgroup of participants and had a destabilizing effect for others which implies significant variability in inter-individual postural control. The aim of this work was to investigate the underlying causes of inter-individual variability by studying the postural parameters of quiet standing before the external stabilization. Eighteen volunteers took part in the experiment where they were standing on an actuated cart for 335 s. In the middle of this period we stabilized their COM in anteroposterior direction for 105 s. To stabilize the COM, we controlled the position of the cart using a double proportional–integral–derivative controller. We recorded COM position throughout the experiment, calculated its velocity, amplitude, and frequency during the quiet standing before the stabilization, and used these parameters as features in hierarchical clustering method. Clustering solution revealed that postural parameters of quiet standing before the stabilization cannot explain the inter-individual variability of postural responses during the external COM stabilization. COM was successfully stabilized for a group of participants but had a destabilizing effect on the others, showing a variability in individual postural control which cannot be explained by postural parameters of quiet-stance.

Changes in postural balance associated with a woman's aging process

CONTEXT

Aging causes a progressive worsening in postural balance, affecting functional independence and increasing the risk of falls.

OBJECTIVE

The aim of the study was to evaluate the effect of aging on the static balance in women from 50-years to 89-years of age.

DESIGN

This was a cross-sectional study, with 400 irregularly active women were evaluated and grouped by age: Group 6^th decade (age 50 to 59) ‒ 58 participants; Group 7^th decade (age 60 to 69) ‒ 214 participants; Group 8^th decade (age 70 to 79) ‒ 92 participants; Group 9^th decade (age 80 to 89) ‒ 36 participants. Postural balance was evaluated using a portable force platform in a standard standing position, with Eyes Open (EO) and Eyes Closed (EC).

RESULTS

In the two measurement conditions, the elderly women in Group 9^th decade presented mediolateral displacement and range, and mean velocity greater than the women's values in Groups 6^th and 7^th decade. In the EO e EC situation, the displacement was higher in the elderly Group 9^th decade compared to younger groups. Group 8^th has a mean velocity greater than Group 6^th decade in the EO situation.

CONCLUSIONS

Posturography showed a decline in postural balance with advancing age, suggesting that the 9^th decade of life is a borderline age to this detriment due to an increase in postural instability.

Impairment of Proprioception in Young Adult Nonradicular Patients with Lumbar Derangement Syndrome

Maintaining body balance is a complex function based on the information deriving from the vestibular, visual, and proprioceptive systems. The aim of the study was to evaluate quiet single stance stability in young adults with lumbar derangement syndrome (LDS) and in the control group of the healthy subjects. The second aim of this study was to determine whether pain intensity, degree of disability, and the level of physical activity can influence postural control in patients with LDS. It is important to underline that selecting a homogeneous group of LBP patients using, for example, mechanical diagnosis and therapy method and Quebec Task Force Classification, can result in an increased sensitivity of the study. The study included 126 subjects: 70 patients with LDS (37 women, 33 men) and the control group 56 healthy volunteers (36 women, 20 men). In case of multiple group comparisons for variables with normal distribution, ANOVA post hoc test was used or, as the nonparametric equivalent, Kruskal-Wallis test. In all these calculations, the statistical significance level was set to p < 0.05. The stability index eyes open for the study group was 88.34 and for the control group 89.86. There was no significant difference in the level of postural control between the study and control groups (p > 0.05). The level of stability index eyes closed (SI EC) for the study group was 71.44 and for the control group 77.1. SI EC results showed significant differences in proprioceptive control during single leg stance between the study and control groups (p < 0.05). The level of pain intensity, the degree of disability, and physical activity level did not influence postural control in the study group with LDS. In summary, patients with LDS showed significantly worse proprioceptive control.

Association between Anthropometric Variables, Sex, and Visual Biofeedback in Dynamic Postural Control Assessed on a Computerized Wobble Board

Anthropometrics and sex influence balance performances, and visual information can change anthropometrics’ relation and the postural sway. Therefore, the aim of the present study was to evaluate the effect of anthropometric characteristics, sex, and visual biofeedback and/or their interaction on a computerized wobble board. Twenty-seven (14 females, 13 males) young adults performed three 30-s double leg stance trials on a wobble board during two conditions: with visual and without visual biofeedback. Visual biofeedback improved (p = 0.010) balance on a wobble board with respect to the condition without visual biofeedback. Regardless of sex, no differences between conditions were found (p = 0.088). When investigating the effect of anthropometrics variables, sex, and their interactions on conditions, a significant main effect of the lower limb/height ratio, sex, and their interaction on the condition without visual biofeedback was found (p = 0.0008; R2 = 0.57). For the visual biofeedback condition, significant effects for sex and body mass (p = 0.0012; R2 = 0.43) and sex and whole-body moment of inertia (p = 0.0030; R2 = 0.39) were found. Results from the present study showed (1) visual biofeedback improved wobble board balance performance; (2) a significant main effect of lower limb/height ratio, sex, and their interaction on the wobble board performances without visual biofeedback emerged; (3) significant effects were found for sex and body mass and sex and moment of inertia in the visual biofeedback condition. Findings from the present study could have an impact on training and evaluations protocols, especially when several populations such as children, athletes, older adults and people with balance disorders are involved.

Multisensory postural control in adults: Variation in visual, haptic, and proprioceptive inputs

Maintaining balance is fundamentally a multisensory process, with visual, haptic, and proprioceptive information all playing an important role in postural control. The current project examined the interaction between such sensory inputs, manipulating visual (presence versus absence), haptic (presence versus absence of contact with a stable or unstable finger support surface), and proprioceptive (varying stance widths, including shoulder width stance, Chaplin [heels together, feet splayed at approximately 60°] stance, feet together stance, and tandem stance) information. Analyses of mean velocity of the Centre of Pressure (CoP) revealed significant interactions between these factors, with stability gains observed as a function of increasing sensory information (e.g., visual, haptic, visual + haptic), although the nature of these gains was modulated by the proprioceptive information and the reliability of the haptic support surface (i.e., unstable versus stable finger supports). Subsequent analyses on individual difference parameters (e.g., height, leg length, weight, and areas of base of support) revealed that these variables were significantly related to postural measures across experimental conditions. These findings are discussed relative to their implications for multisensory postural control, and with respect to inverted pendulum models of balance. (185 words).

Anthropometric and demographic properties affect balance in healthy adults: an observational study

BACKGROUND

Anthropometric and demographic properties may affect balance, but there is no consensus on this subject; so, there is a need for studies that explore it. This study aimed to assess the relationship between balance and anthropometric as well as demographic properties; and to determine the effect of anthropometric and demographic properties on balance in healthy adults.

METHODS

Sixty healthy adults were included in this study. The ages of the participants were questioned; height, body weight, Body Mass Index, head circumference, upper extremity, lower extremity, and foot length were evaluated, and shoe numbers were recorded. Balance assessments were performed with the Balance Master System device.

RESULTS

The mean age of the participants was 23.50±1.97 years. The balance developed with age (P<0.05), while there was a negative correlation between height and balance (P<0.05). Weight gain affected balance negatively (P<0.05). The increase in head circumference, extremity, and foot length was associated with a deterioration in balance (P<0.05).

CONCLUSIONS

The results of the current study were showed that anthropometric and demographic properties affect balance. The increase in some of the anthropometric and demographic properties including height, weight, head circumference, extremity, and foot length harms the balance. During balance assessments, anthropometric and demographic characteristics should be considered as a factor that affects balance.

Balance impairment in survivors of pediatric brain cancers: risk factors and associated physical limitations

PURPOSE

The study aims were to determine the prevalence of balance impairments in adult survivors of pediatric central nervous system (CNS) tumors, and to identify predictors of and limitations associated with balance impairments.

METHODS

Participants were adult survivors (N = 329) of pediatric CNS tumors. Balance was considered impaired among those with composite scores < 70 on the sensory organization test. Potential predictors of impaired balance were evaluated with generalized linear regression. Multivariable logistic regression was used to evaluate associations between balance impairment and function.

RESULTS

Balance impairment was observed in 48% of survivors, and associated with infratentorial tumor location (OR = 4.0, 95% CI, 2.0-7.6), shunt placement (OR = 3.5, 95% CI, 1.8-6.7), increased body fat percentage (OR = 1.1, 95% CI, 1.0-1.1), hearing loss (OR = 11.1, 95% CI, 5.6-22.2), flexibility limitations (OR = 2.0, 95% CI, 1.0-3.9), peripheral neuropathy (OR = 2.4, 95% CI, 1.2-4.5), and cognitive deficits (OR = 2.2, 95% CI, 1.1-4.7). In adjusted models, impaired balance was associated with limitations in overall physical performance (OR = 3.6, 95% CI, 2.0-6.3), mobility (OR = 2.6, 95% CI, 1.5-4.4), diminished walking endurance (OR = 2.9, 95% CI, 1.7-5.0), and non-independent living (OR = 2.0, 95% CI, 1.0-4.3).

CONCLUSIONS

Nearly half of adult survivors of pediatric CNS tumors have impaired balance, which is associated with mobility and physical performance limitations. Interventions to address the complex needs of this population should be prioritized.

IMPLICATIONS FOR CANCER SURVIVORS

Survivors with identified risk factors should be closely evaluated for presence of balance impairment. Interventions tailored to improve balance also can positively affect function and mobility in survivors.

DYNAMIC POSTURAL BALANCE IS MEDIATED BY ANTHROPOMETRY AND BODY COMPOSITION IN OLDER WOMEN

OBJECTIVE

To investigate the relationship between anthropometry and body composition with dynamic postural balance in elderly women with low bone mineral density (BMD).

METHODS

45 older women (≥ 60 years), low BMD and nutritional diagnosis of low weight to overweight. For the assessment of body composition, Dual energy X-ray emission densitometry and anthropometric examination were used to measure: body mass (kg), height (cm) and BMI (k/m2). The assessment of dynamic postural balance was performed by the mini Balance Master Evaluation System clinical test and the computerized Balance Master® System test by the Sit to Stand and Step Up/Over tests.

RESULTS

There was a negative correlation between miniBESTest (r = - 0.566; p ≤ 0.001) and time to ascend and descend step (r = - 0.393; p ≤ 0.007) with fat mass, and positive correlation with miniBESTest (r = 0.526; p ≤0.001) and time to go up and down a step with muscle mass (r = 0.297; p ≤ 0.04). As for anthropometric variables, only height showed a positive correlation (r = 0.296; p ≤ 0.04) with the speed in the sit and stand test.

CONCLUSION

Lean mass reduces postural oscillations; in contrast, fat mass negatively interfered with dynamic postural balance in women with low BMD. Height was related to dynamic postural balance, the taller the elderly, the worse their balance. Level of Evidence II, Prognostic Studies - Investigating the Effect of a Patient Characteristic on the Outcome of Disease.

ANTHROPOMETRIC FACTORS AND BODY COMPOSITION AND THEIR RELATIONSHIP WITH DYNAMIC BALANCE TESTS

ABSTRACT Introduction: The limit of stability is characterized by the maximum angle of inclination that an individual can reach and greater variability in extreme conditions; it is a bold and/or dangerous motor control strategy. Objective: Assess whether anthropometric measurements and body composition interfere with limits of stability and weight-bearing at different speeds in adults. Methods: Eighty-seven subjects of both sexes aged between 20 and 40 years were analyzed using anthropometric assessment and body composition. A force platform, limits of stability (LoS) and rhythmic weight shift (RWS) tests were used for the balance assessments. Results: In the LoS test, being female was negatively correlated with foot size and reaction time, and positively correlated with maximum excursion. In the RWS test, the female group had a negative correlation with height and upper limb length (ULL), with mediolateral directional control. The male group had a negative correlation with ULL and laterolateral directional control. Conclusion: Body composition variables do not interfere in the LoS and RWS tests in subjects with normal body mass index (BMI) values, except for bone densitometry (BMD) in women. As regards anthropometric parameters, height, ULL and foot size in the female and male groups were as follows: ULL and foot size exert little influence on postural balance control. Level of evidence II, Diagnostic studies - Investigation of a diagnostic test.

Neuromuscular performance of balance and posture control in childhood and adolescence

This study examined a potential age-dependency of both posture and stability (balance) control in children and adolescents in a healthy population. Body posture with open and closed eyes was examined for a total of 456 test persons (age 6.7–17.6 years. Posture parameters (posture index, upper body tilt, trunk tilt) were assessed in the sagittal plane. Additionally, the oscillation of the center of pressure with open and closed eyes was additionally analyzed in a sub-sample of 318 subjects.

Absolute values of stability control parameters changed significantly during childhood and adolescence for both boys (p = 0.005) and girls (p = 0.01). Relative changes of stability and posture parameters when closing the eyes did not change (p > 0.05) and were independent of age, gender or sports activity in healthy children and adolescents.

The shifting of the body segments towards each other, as a result of the loss of visual information, does not seem to be primarily responsible for the increase in COP fluctuation. This is a further indication that stability control and posture control are complex interdependent mechanisms whose interaction is not yet fully understood.

Balance Control in Obese Subjects during Quiet Stance: A State-of-the Art

Obese individuals are characterized by a reduced balance which has a significant effect on a variety of daily and occupational tasks. The presence of excessive adipose tissue and weight gain could increase the risk of falls; for this reason, obese individuals are at greater risk of falls than normal weight subjects in the presence of postural stress and disturbances. The quality of balance control could be measured with different methods and generally in clinics its integrity is generally assessed using platform stabilometry. The aim of this narrative review is to present an overview on the state of art on balance control in obese individuals during quiet stance. A summary of knowledge about static postural control in obese individuals and its limitations is important clinically, as it could give indications and suggestions to improve and personalize the development of specific clinical programs.

Posturographic measures did not improve the predictive power to identify recurrent falls in community-dwelling elderly fallers

OBJECTIVE

This study aimed to evaluate if posturography can be considered a recurrent fall predictor in elderly individuals.

METHODS

This was a cross-sectional study. A total of 124 subjects aged 60 to 88 years were evaluated and divided into two groups-the recurrent fallers (89) and single fallers (35) groups. Patients' sociodemographic characteristics were assessed, and clinical testing was performed. The functional test assessment instruments used were timed up and go test (TUGT), Berg Balance Scale (BBS), five times sit-to-stand test, and Falls Efficacy Scale (to measure fear of falling). Static posturography was performed in a force platform in the following three different situations-eyes open (EO), eyes closed (EC), and EO dual task.

RESULTS

There were significant differences between the single and recurrent fallers groups regarding the fear of falling, the Geriatric Depression Scale score, the mean speed calculated from the total displacement of the center point of pressure (COP) in all directions with EO, and the root mean square of the displacement from the COP in the mediolateral axis with EC. Based on the hierarchical logistic regression model, none of the studied posturographic variables was capable of significantly increasing the power of differentiation between the recurrent and single fallers groups. Only TUGT with a cognitive distractor (p<0.05) and the BBS (p<0.01) presented with significant independent predictive power.

CONCLUSION

TUGT with a cognitive distractor and the BBS were considered recurrent fall predictors in elderly fallers.

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 (τ_b = 0.3 to 0.5, p < 0.01 to <0.0001). SBMA scores and COM velocity were significantly correlated only for single leg stances (τ_b = −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.

Posturographic characteristics of the standing posture and the effects of the treatment of obesity on obese young women

To determine the impact of body weight on quiet standing postural sway characteristics in young women, this research compared spontaneous oscillations of the center of foot pressure (COP) between 32 obese (BMI: 36.4 ± 5.2 kg/m²), and 26 normal-weight (BMI: 21.4 ± 1.5 kg/m²) women and assessed the influence of obesity treatment and body weight reduction on postural sway. Trajectories of the COP were assessed while the subjects were standing quietly with eyes open (EO) and closed (EC). Both in the sagittal (AP) and frontal (ML) planes the sway range, average velocity, and maximal velocity of COP were calculated. Moreover, the total average and maximal velocities were computed. In the obese group, the tests were performed twice–before and after the obesity treatment. A greater (18% in EC) AP sway range and a substantial reduction of ML sway (25% in EO, 22% in EC) were observed in the obese women. The total COP velocities (average and maximal) were decreased in obese women (20% and 20% in EO) as well as the velocities in the frontal plane (EO: 33%, 41%; EC: 34%, 40%). Body weight reduction resulted in significant changes in postural sway. The following parameters increased: ML sway range (28% in EO), average (20% in EO, 16% in EC) and maximal ML (20% in EO) velocities. The results indicate that young obese women in the habitual standing position are characterized by the destabilizing influence of mass in the sagittal plane only in the absence of a visual control. This effect is dominated by the stabilizing mass effect in the frontal plane, which affects overall postural stability when standing. The reduction of body mass enables a decrease in ML static stability, likely due to natural changes in the base of support while standing.

Important Movement Concepts: Clinical Versus Neuroscience Perspectives

Human movement is complex, presenting clinical and research challenges regarding how it is described and investigated. This paper discusses the commonalities and differences on how human movement is conceptualized from neuroscientific and clinical perspectives with respect to postural control; the limitations of linear measures; movement efficiency with respect to metabolic energy cost and selectivity; and, how muscle synergy analysis may contribute to our understanding of movement variability. We highlight the role of sensory information on motor performance with respect to the base of support and alignment, illustrating a potential disconnect between the clinical and neuroscientific perspectives. The purpose of this paper is to discuss the commonalities and differences in how movement concepts are defined and operationalized by Bobath clinicians and the neuroscientific community to facilitate a common understanding and open the dialogue on the research practice gap.

The effects of breath alcohol concentration on postural control

BACKGROUND

Two of the 3 standardized field sobriety tests that U.S. law enforcement uses at roadside checks have a postural equilibrium component to them. Those tests have been validated to detect impairment caused by blood alcohol concentrations (BACs) of 0.08 g/dL or above. Many medical and traffic safety associations support a lower limit, and one state, Utah, has passed a law to lower the limit to 0.05 g/dL. Many studies have examined the effects of alcohol on postural control (of which postural equilibrium is a component), with a consensus emerging that impairment is usually found at BACs greater than 0.06 g/dL. Most of these studies, however, had a relatively small number of subjects, usually between 10 and 30. The current study collected data from a much larger sample.

OBJECTIVE

The objective of this study was to provide additional evidence that posture control is negatively affected at BACs greater than 0.06 g/dL or breath alcohol concentrations (BrACs) of 0.06 g/210 L.

METHOD

This was a between-subjects study, with BrAC group as the independent variable (5 levels: 0.00, 0.04, 0.06, 0.08, and 0.10 g/210 L); 4 measures of postural control as the dependent variables; and age, height, and weight as the covariates. Posture control was measured with a force-sensing platform connected to a computer. The feet's center of pressure (CoP) on the platform was recorded and the corresponding movement of the body in the anterior-posterior and lateral planes was derived. Participants (N = 96) were randomly assigned to one of the BrAC groups. Positive BrAC groups were compared to the zero BrAC group. Data were examined with hierarchical multiple regression.

RESULTS

Adjusted for age, height, and weight, the main effect of lateral CoP with eyes open was not statistically significant. There was a statistically significant main effect of alcohol on anterior-posterior CoP excursion with eyes open and with eyes closed and lateral CoP excursion with eyes closed. For all 3 of those variables, only BrACs of 0.08 and 0.10 g/210 L produced differences against zero BrAC. Although the main effect of alcohol on Lateral CoP Excursion with eyes open was not statistically significant, the contrasts between 0 and 0.08 and 0 and 0.10 g/210L BrAC were in the hypothesized direction.

CONCLUSION

The current study did not directly address the issue of whether the sobriety tests are sensitive to BrACs of 0.05 g/210 L or above; rather, it provides additional evidence that postural control, one of the components of those tests, is relatively unaffected by BrACs lower than 0.08 g/210 L. Additional research is needed on the diagnostic characteristics of the sobriety tests at BrACs lower than 0.08 g/210 L.

Effect of body mass index and fat mass on balance force platform measurements during a one-legged stance in older adults

The purpose of this study was to evaluate the impact of body mass index (BMI) and fat mass on balance force platform measurements in older adults. The sample consisted of 257 participants who were stratified into four groups by BMI: low weight, normal weight, pre-obesity and obesity. For fat mass variables, older individuals were classified into low and high-fat mass. All groups investigated performed three trials of one-legged stance balance on a force platform. Center of pressure (COP) domain parameters were computed from the mean across trials. Analysis of variance results revealed no significant interactions for groups and sexes for all COP parameters. Comparable balance results were found for BMI and fat groups for all COP parameters. A statistical effect (P < 0.05) was only reported for sex differences for COP parameters, regardless of BMI and fat mass variables. Overall, women presented better balance than men. In conclusion, BMI and fat mass do not seem to influence the balance of older adults during a one-leg stance task.

Controle postural de mulheres com dismenorreia primária em dois momentos do ciclo menstrual

RESUMO A dismenorreia primária (DP) é uma dor pélvica ou abdominal inferior relacionada à menstruação, associada a pontos dolorosos miofasciais, cuja presença é capaz de alterar a percepção somatossensorial e a ativação muscular, o que pode interferir no controle postural. O objetivo deste estudo foi verificar a influência da DP no controle postural estático de mulheres em dois momentos do ciclo menstrual, com e sem dor. Foram avaliadas 19 universitárias (22,4±3,0 anos) com DP por meio da escala visual analógica, algometria e plataforma de força. Os dados foram submetidos à estatística descritiva e verificados quanto à normalidade (Shapiro-Wilk) e às variáveis comparadas, utilizando-se o teste t de Student e o teste de Wilcoxon. O grupo avaliado apresentou uma dor considerada moderada (4,1±2,3), e os valores de limiar de dor à pressão foram menores no momento com dor quando comparado ao sem dor, na região do abdômen direito (p=0,04) e lombossacral bilateral (p<0,05), indicando maior sensibilidade local. Quanto ao controle postural, houve maior amplitude de deslocamento anteroposterior do centro de pressão, tanto na condição “olhos abertos” quanto “olhos fechados”, bem como na velocidade média e área da elipse do centro de pressão, na condição “olhos fechados”, durante o momento com DP. Essas alterações indicam maior necessidade de ajustes posturais na DP, possivelmente em virtude de uma interferência da dor sobre a propriocepção. Concluiu-se que houve maior sensibilidade dolorosa na fase menstrual do ciclo e que a dor interferiu sobre o controle postural deste grupo, eventos que foram intensificados pela ausência de visão.

Age related changes in balance performance during self-selected and narrow stance testing

BACKGROUND

Various balance tests have been considered as fall risk screening tools however there is a lot of variability in the methods and outcome measures reported. Based on previous research examining age-related changes in balance and differences between fallers and nonfallers, the purpose of this investigation was to examine age-related balance changes, as reflected in medial-lateral center of pressure (CP) velocity, in community-dwelling/independently living adults (≥60years) during self-selected and narrow stance testing with eyes opened and closed.

METHODS

Two hundred and thirty adults aged 60yrs or older completed one 45s trial under two stances (self-selected, narrow) and two visual conditions (eyes opened, eyes closed). Average medial-lateral CP velocity was computed from the CP data, with preliminary analysis demonstrating positive skewness and association with body height. A sway velocity index (SVI) was created by a natural logarithm transformation and dividing by body height. Multiple linear regression was used to determine the association between age, visual condition, stance, and sex with SVI.

RESULTS

Age, visual condition, stance and sex were all demonstrated to be significant predictors of SVI, with the combination of the predictors explaining 25% of the variance in the SVI.

CONCLUSIONS

These results confirm the balance testing protocol and SVI to be sensitive to age-related changes in balance performance. The results of this study should help future research aimed towards establishing a quick, easy to administer, and readily interpretable instrumented test for assisting with identifying potential balance impairments in older adults who have yet to demonstrate outward deficits.

Interrelationship between postural balance and body posture in children and adolescents

[Purpose] This study examined possible interrelationships between postural sway and posture parameters in children and adolescents with a particular focus on posture weakness. [Subjects and Methods] 308 healthy children and adolescents (124 girls, 184 boys, aged 12.3 ± 2.5 years) participated in the study. Posture parameters (posture index, head protrusion, trunk inclination) were determined based on posture photos in the sagittal plane. Postural sway was measured during 20 seconds on a force plate. The Pearson’s product-moment correlation coefficients between the anthropometric and posture parameters and the sway path length (SPL) were calculated, as well as the coefficient of determination R². [Results] There is a weak but significant correlation between age or body mass index of the test subjects and the SPL. There is no statistically significant correlation between posture parameters and the SPL. Children and adolescents with posture weakness do not exhibit a changed SPL. [Conclusion] Therefore, therapy of poor posture must be considered separately from therapeutic measures for the improvement of balance skills.

Energy Cost of Standing in a Multi-Ethnic Cohort: Are Energy-Savers a Minority or the Majority?

Background

The disease risks associated with sedentary behavior are now firmly established, and consequently there is much interest in methods of increasing low-intensity physical activity. In this context, it is a widely held belief that altering posture allocation can modify energy expenditure (EE) to impact upon body weight regulation and health. However, we recently showed the existence of two distinct phenotypes pertaining to the energy cost of standing–with the majority of a Caucasian cohort showing no sustained increase in EE during standing relative to sitting. Here we investigated whether this phenomenon is also observed across a multi-ethnic male cohort.

Objective

To determine the magnitude and time-course of changes in EE and respiratory quotient (RQ) during steady-state standing versus sitting, and to explore inter-individual variability in these responses across 4 ethnic groups (European, Indian, Chinese, African)

Design

Min-by-min monitoring using posture-adapted ventilated-hood indirect calorimetry was conducted in 35 healthy, men (20–43 years) during 10 min of steady-state standing versus sitting comfortably.

Results

69% of subjects showed little or no increase (<5%) in EE during standing compared to sitting (energy savers). Furthermore, the proportion of energy savers did not significantly differ between ethnic groups, despite ethnic differences in anthropometry; with body weight as the primary predictor of the energy cost of standing maintenance (r² = 0.30, p = 0.001).

Conclusion

Our results indicate that the majority of individuals in a multi-ethnic cohort display a postural energy-saver phenotype. The mechanisms by which the large majority of individuals appear to maintain sitting and standing postures at the same energetic cost remains to be elucidated but is of considerable importance to our understanding of the spontaneous physical activity compartment of EE and its potential as a target for weight regulation.