Primary dysmenorrhea and postural control: Is it a problem only during menstruation?

BACKGROUND

The effects of the menstrual cycle and primary dysmenorrhea (PD) on phase-related cognitive and physical functions are controversial. This study was carried out to examine whether women with PD showed a different physical function or dual-tasking response than women without PD at times other than menstruation.

METHODS

Women with or without PD were recruited for the study. Individuals assessed on the first day of the menstruation and the day they reported themselves as well being (feeling good day-FGD). Zebris © FDM Type Force Platform was used to evaluate postural stability. Individuals have were asked to perform to a 3-step balance test protocol; the first session: comfortable upright standing; the second session: standing with a motor task; the third session: standing with a cognitive task (counting backward). Correctly calculated numbers were also recorded.

RESULTS

The number of correct answers given by individuals during the cognitive dual-task was similar on the first day of menstruation and FGD (p > 0.05). In the control group, no difference was observed between the first days of menstruation and the evaluations on FGD days with dual-task (p > 0.05). In individuals with PD, there was no difference between the measurements at different times (p > 0.05). However, in the assessment with the motor dual-task on the first day of menstruation; postural sway increased (p < 0,05). In FDG measurement; distortion in postural stability was observed with the cognitive task (p < 0,05). In the assessments performed on the first day of menstruation, there was no difference in any parameters between the groups (p > 0.05). In the measurements made on FGD day with the cognitive task; there was a difference between the groups (p < 0,05). Individuals with PD had higher postural sway.

SIGNIFICANCE

This study showed that the primary dysmenorrhea is not only a problem for females during menstruation, primary dysmenorrhea causes impaired ability of the individual to perform dual-tasking and continuously affects postural stability.

Characterizing inter-limb synchronization after incomplete spinal cord injury: A cross-sectional study

BACKGROUND

Individuals with incomplete spinal cord injury (iSCI) demonstrate greater postural sway and increased dependency on vision to maintain balance compared to able-bodied individuals. Research on standing balance after iSCI has focused on the joint contribution of the lower limbs; however, inter-limb synchrony in quiet standing is a sensitive measure of individual limb contributions to standing balance control in other neurological populations. It is unknown if and how reduced inter-limb synchrony contributes to the poor standing balance of individuals with iSCI.

RESEARCH QUESTION

How does an iSCI affect inter-limb synchrony and weight-bearing symmetry in standing?

METHODS

Eighteen individuals with non-progressive motor iSCI and 15 age- and sex-matched able-bodied individuals (M-AB) were included in the study. Participants stood in a standardized position on two adjacent force plates in eyes open and closed conditions for 70 s per condition. Net centre-of-pressure (COP) root mean square (RMS), net COP velocity, COP inter-limb synchrony (i.e. cross-correlation between left and right COP), and weight-bearing asymmetry (i.e. vertical force from each limb over total vertical force) were calculated. Muscle strength of the lower limbs was assessed with manual muscle testing.

RESULTS

Individuals with iSCI demonstrated reduced inter-limb synchrony when standing with eyes open and eyes closed, but did not differ to M-AB with respect to weight-bearing asymmetry. They also produced greater net COP RMS and velocity when compared to M-AB. Muscle strength of the two lower limbs demonstrated an overall asymmetry in individuals with iSCI.

SIGNIFICANCE

Individuals with iSCI demonstrated impaired balance control as evidenced by reduced inter-limb synchrony and greater COP RMS and velocity compared to M-AB individuals. This increased understanding of how balance control is impaired following iSCI may inform balance assessment and intervention for this population. Future work examining the association between inter-limb synchrony and the occurrence of falls in iSCI is warranted.

Investigating the effects of appropriate fitting footwear on functional performance level, balance and fear of falling in older adults: A comparative-observational study

The aim of the study was to assess the characteristics of footwear altogether and to compare the effect of appropriate-fitting and ill-fitting footwear on functional performance, balance, and fear of falling (FoF) in older adults. Individuals who wore appropriate-fitting (n = 61) or ill-fitting footwear (n = 92) were enrolled in the study. Footwear was evaluated using the Footwear Assessment Scale (FAS). The participants were assessed using the Berg Balance Scale (BBS) for balance, the Timed Up and Go test for functional performance and the Activities-specific Balance Confidence scale for FoF. Tests were conducted twice for each individual with or without footwear. Differences between the groups were analyzed using the MANOVA for scores of balance, performance and fear of falling and Chi-squared test for homogeneity. The Paired t-test was used to compare test scores with or without footwear. It was concluded that appropriate-fitting footwear improves balance, reduces fear of falling and may affect functional performance positively. ClinicalTrials.gov No: NCT04151654.

Generalized joint hypermobility, scoliosis, patellofemoral pain, and physical abilities in young dancers

Background

Many young girls with generalized joint hypermobility (GJH) choose to participate in dance because their bodies are suited for this activity. Scoliosis tends to occur often in thin girls, who also are more likely to choose dance. Both anomalies (GJH and scoliosis) may be related to reduced abilities such as diminished strength and insufficient postural balance, with increased risk for musculoskeletal conditions. The main objectives of the present study were to determine the prevalence of dancers with GJH, the prevalence of dancers with scoliosis, and the prevalence of dancers with these two anomalies; and, to determine differences in physical abilities and the presence of patellofemoral pain (PFP) between young female dancers with and without such anomalies.

Methods

One hundred thirty-two female dancers, aged 12–14 years, were assessed for anthropometric parameters, GJH, scoliosis, knee muscle strength, postural balance, proprioception ability, and PFP.

Results

GJH was identified in 54 dancers (40.9%) and scoliosis in 38 dancers (28.8%). Significant differences were found in the proportion of dancers with no anomalies (74 dancers, 56.1%) and dancers with both anomalies (34 dancers, 25.8%) (p < .001). Dancers with both anomalies had reduced dynamic postural balance in the anterior direction (p = .023), reduced proprioception ability (p < .001), and weaker knee extensors (p = .036) and flexors (p = .040) compared with dancers with no anomalies. Among dancers with both anomalies, 73.5% suffered bilateral PFP, 17.6% suffered unilateral PFP, and 8.8% had no PFP (p < .001).

Conclusions

A high prevalence of young girls participating in dance classes had GJH, as the increased joint flexibility probably provides them with some esthetic advantages. The high prevalence of scoliosis found in these young dancers might be attributed to their relatively low body mass, their delayed maturation, and the selection process of dancers. Dancers with both GJH and scoliosis had decreased muscle strength, reduced postural balance, reduced proprioception, with higher risk of PFP. The main clinical implications are the need to reduce the risk of PFP among dancers by developing appropriate strength and stabilizing exercises combined with proprioceptive and postural balance training, to improve the correct alignment of the hyperextended and hypermobile joints, and to improve their supporting muscle strength.

Integrating Technology Into Clinical Practice for the Assessment of Balance and Mobility: Perspectives of Exercise Professionals Practicing in Retirement and Long-term Care

Objective

To explore exercise professionals’ perspectives on technology integration for balance and mobility assessment practices in retirement and long-term care.

Setting

A private residential care organization in Ontario, Canada, with 18 sites providing accommodation and services for older adults.

Design

A qualitative descriptive approach was used including semistructured focus group interviews. Open-ended questions explored perceptions of technology integration along with factors influencing its adoption. Analysis involved preliminary coding based on research questions, review and discussion of emerging themes, and final, resultant coding for each category.

Participants

Exercise professionals (kinesiologists and exercise therapists) (N=18).

Interventions

Not applicable.

Main Outcome Measures

Not applicable.

Results

All participants felt that technology could enhance their practice by supporting programming, communication, and/or information management. Potential barriers to technology integration related primarily to the need to accommodate the broad range of complex health conditions present among clients, which would impact (1) their ability to engage with the technology and (2) relevance of technology-derived outcomes. Specific concerns related to individuals with significant cognitive and/or functional impairment. Solutions to these barriers emphasized the need for flexible technology and appropriate normative data to maximize the potential for uptake.

Conclusions

The participating exercise professionals working in a retirement and long-term care setting saw technology as a potentially effective addition to current clinical practice. To increase the likelihood for clinical uptake, technology must be maximize flexibility in order to accommodate a wide range of physical and cognitive abilities and meet specific needs related to setting and job responsibilities. The findings emphasize the need for continuous dialogue between technology producers and end users for successful development and implementation.

Testing the Validity of the Diamond Steps Test for Balance in Healthy Adults

Objectives

To test the validity of the Diamond Steps Test (DST), a new test to assess balance.

Design

This cross-sectional study evaluated the validity of the DST, a brief new balance assessment tool.

Setting

The implementation site was the rehabilitation center of a hospital. Data collection was conducted from February to June 2017.

Participants

Healthy adults (N=65) between the ages of 40 and 72 years who volunteered to participate.

Interventions

Not applicable.

Main Outcome Measures

Two measures were used to assess DST: the time required to step around the diamond 5 times (5-DS) and the time required to step around the diamond twice, once using the dominant foot and the other using the non-dominant foot (LRDS).

Results

Multiple regression analysis was performed for each of the 2 methods for measuring DST. Five variables were predictive of DST as measured by the 5-DS test: the 10-Second Open Close Stepping Test, timed Up and Go (TUG) test, Y Balance Test (YBT) posterolateral reach for the left leg, Standing on One Leg with Eyes Closed (SOLEC) test for the right leg, and sex. The coefficient of determination was 0.54. For DST measured by the LRDS, 4 variables were found to be predictive: the 30-Second Chair Stand Test, YBT posterolateral reach for the left leg, TUG, and SOLEC for the right leg. The coefficient of determination was 0.49.

Conclusion

The DST was shown to assess 7 of the 9 components of balance (static stability, functional stability limits, underlying motor systems, anticipatory posture control, dynamic stability, reactive postural control, and sensory integration), suggesting that it is a valid test to use for balance assessment.

•

We evaluated the validity of a new balance assessment tool, the Diamond Steps Test (DST).

•

The DST was found to assess 7 of the 9 components of balance.

•

Most components of balance can be quickly assessed using the DST.

•

Time to step around the diamond 5 times is a valid method to assess the DST.

A Pilot Study of the Feasibility and Effects of Table Tennis Training in Parkinson Disease

Objective

To investigate feasibility and effects of table tennis training on balance control and physical function in individuals with Parkinson disease.

Design

Single group, observational, before-after trial.

Setting

Table tennis training in a gymnasium.

Participants

Community-dwelling individuals with Parkinson disease (N=9; 5 men, 4 women) with an average age of 66.9 years, average time since diagnosis of 8.6 years, and a modified Hoehn and Yahr score between 2 and 2.5 participated in this study. Participants were recruited via newspaper advertisement, at the patient organization, and at the university hospital outpatient clinic. Eight participants completed the study. One participant withdrew for logistical reasons.

Interventions

Group training program consisting of 2 table tennis training sessions per week (120min each) for 10 weeks.

Main Outcome Measures

The primary outcome was feasibility, including attendance rate, drop-out rate, a final questionnaire assessing the participants' experience during the intervention, and any adverse events. The primary effect outcome was the Mini Balance Evaluation Systems Test (Mini-BESTest). Secondary effect outcomes were Parkinson's disease questionnaire-8, European quality of life questionnaire, Montgomery Åsberg Depression Rating Scale (MADRS), Unified Parkinson's Disease Rating Scale, 10-meter walk test, generic walking scale, activities-specific balance confidence scale, and physical activity measured with an accelerometer and the Frändin-Grimby scale.

Results

The average attendance rate was 84%. There were no adverse events reported. The participants reported that the training improved well-being. The mean total score on the Mini-BESTest before and after intervention was 21.2 versus 23.3 (P=.093). Statistically significant positive effects without adjustment for multiple comparisons were found for MADRS and the Frändin-Grimby scale.

Conclusions

This study demonstrates that table tennis training is safe and feasible, and may have the potential to improve balance control, mental well-being, and self-reported physical activity level. Further studies are required before table tennis can be considered an evidence-based recommendation for individuals with Parkinson disease.

Immediate impact of extremity manipulation on dual task performance: a randomized, crossover clinical trial

BACKGROUND

Previous research demonstrated that manipulation of the extremities was associated with changes in multisegmental postural sway as well as improvement in a lower extremity balancing task. We were interested if these effects would extend to an upper extremity task. Our aim in this study was to investigate whether extremity manipulation could influence dual task performance where the explicit suprapostural task was balancing a water filled tube in the frontal plane.

METHODS

Participants were healthy volunteers (aged 21-32 years). Upper- or lower-extremity manipulations were delivered in a participant and assessor blinded, randomized crossover, clinical trial. Postural (center of pressure) and suprapostural (tube motion) measurements in the frontal plane were made pre-post manipulation under eyes open and eyes closed conditions using a BTrackS™ force plate and a Shimmer inertial measurement unit, respectively. Pathlength, range, root mean square and sample entropy were calculated to describe each signal during the dual task performance.

RESULTS

There was no main effect of manipulation or vision for the suprapostural task (tube motion). However, follow-up to interaction effects indicates that roll pathlength, range and root means square of tube motion all decreased (improvement) following lower extremity manipulation with eyes open. Regarding the postural task, there was a main effect of manipulation on mediolateral center of pressure such that pathlength reduced with both upper and lower extremity manipulation with larger decreases in pathlength values following upper extremity manipulation.

CONCLUSION

Our findings show that manipulation of the extremities enhanced stability (e.g. tube stabilization and standing balance) on performance of a dual task. This furthers the argument that site-specific manipulations influence context specific motor behavior/coordination. However, as this study focused only on the immediate effects of extremity manipulation, caution is urged in generalizing these results to longer time frames until more work has been done examining the length of time these effects last.

TRIAL REGISTRATION

Clinicaltrials.gov , NCT03877367 , Registered 15 March 2019. Data collection took place July 2019.

A vicious cycle of fear of falling avoidance behavior in Parkinson's disease: A path analysis

BACKGROUND

Postural instability (PI) in Parkinson's disease (PD) is associated with several negative downstream consequences.

OBJECTIVE

The purpose was to explore the validity of a theoretical model of these downstream consequences arranged in a vicious cycle wherein PI leads to decreased balance confidence, which in turn leads to increased fear of falling (FOF) avoidance behavior, which in turn leads to decreased physical conditioning, which then feeds back and negatively affects PI.

METHODS

A path analysis of cross-sectional data from 55 participants with PD was conducted. The four constructs in the model connected in succession were: 1. PI (principal components analysis (PCA) composite of the Unified Parkinson's Disease Rating Scale PI and Gait Difficulty score, Timed Up and Go test, and Berg Balance Scale); 2. balance confidence (Activities-Specific Balance Confidence Scale); 3. FOF avoidance behavior (PCA composite of the FOF Avoidance Behavior Questionnaire and average number of steps per day); and, 4. physical conditioning (2-Minute Step Test).

RESULTS

The path model was an excellent fit to the data, χ2 (7) = 7.910, p = .341, CFI = 0.985, TLI = 0.968, RMSEA = 0.049 (90% CI: 0.000 to 0.179). The moderate to strong and uniformly significant parameter estimates were -0.519, -0.651, -0.653, and -0.570, respectively (ps < 0.01).

CONCLUSIONS

PI directly and inversely predicted balance confidence, which in turn directly and inversely predicted FOF avoidance behavior. Furthermore, FOF avoidance behavior directly and inversely predicted physical conditioning, which directly and inversely predicted PI, thereby closing the cycle. These findings highlight the downstream consequences of PI in PD and support the notion of a vicious cycle of FOF avoidance behavior.

Does sensorimotor training influence neuromuscular responses, balance, and quality of life in diabetics without a history of diabetic distal polyneuropathy?

OBJECTIVE

To evaluate the effect of supervised and home sensorimotor training on static postural balance (SPB), quality of life (QL), and neuromuscular responses of Type 2 Diabetics (DM-2).

DESIGN

Randomized controlled blind study with DM-2 patients, between 45 and 64 years old, of both sexes, divided into 3 groups: Control Group - CG (n = 27), Home Training Group - HTG (n = 27), and Supervised Training Group - STG (n = 26). The subjects were evaluated before and at the end of 3 months of treatment, with a four-week follow-up. The intervention was held twice a week, for 45 min, divided into three phases: warm-up, sensorimotor training, and cool-down. The primary outcome was SPB, using the force platform. Secondary outcome: questionnaires and clinical measures related to diabetic foot and knee flexor-extensors using isokinetic dynamometry.

RESULTS

In the baseline, the characteristics were similar between groups and between times. Tactile and vibratory sensitivity demonstrated the absence of symptoms of peripheral neuropathy in diabetic patients. In the intra-group comparison, there was a significant increase in the classification without symptoms of diabetic distal polyneuropathy in the HTG and STG groups (p < 0.05) and there were no significant effects on other clinical outcomes and QL and SPB, muscle strength, and sense of knee joint position.

CONCLUSION

The intervention showed no improvement in SPB, QL, and other clinical outcomes of DM-2 patients. Thus, no differences were found between the groups, considering that the patients did not present clinical characteristics of diabetic distal polyneuropathy.

Postural balance effects from exposure to multi-axial whole-body vibration in mining vehicle operation

Twenty participants (18 males and 2 females) completed postural stability assessments before and after 4-h exposure to whole body vibration (WBV) in four experimental conditions: (a) vertical-dominant WBV with vertical passive air suspension, (b) multi-axial WBV with vertical passive air suspension, (c) multi-axial WBV with multi-axial active suspension, and (d) no WBV condition. Center of pressure (COP)-based postural sway measures significantly increased following multi-axial WBV exposure. Increase in COP velocity and displacement following multi-axial WBV was significantly higher than the increase in all the other exposure conditions. However, no significant differences between the WBV conditions were observed in functional limits of stability and anticipatory postural adjustments. While our results show standing balance to be impaired following the multi-axial WBV exposure of off-road mining vehicles, dynamic stability across a broader range of conditions needs to be understood to causally link postural stability decrements to increased fall-risks associated with off-road vehicle operators.

Are bioelectrical parameters and functionality associated with postural control in the elderly?

BACKGROUND

Alterations in bioimpedance parameters and postural control occur with aging and contribute to the increased risk of falls. The aim of this study was to evaluate the balance behavior in relation to bioimpedance and functionality.

METHODS

We evaluated 21 elderly (men: 77.3 ± 9.5 years; women: 74.2 ± 9.6 years). The balance in standing posture was measured by the movement of the pressure center in seven positions. Bioimpedance was defined by its parameters resistance, reactance and phase angle, and functionality through the Timed Up and Go Test and Short Physical Performance Battery.

FINDINGS

In the analysis of the mediolateral velocity at the positions feet separated with open and closed eyes, feet together with eyes closed and semi-tandem with eyes open on the platform, an inverse correlation between balance and bioimpedance variables were verified for all models, with a coefficient of determination varying between 20% and 74%. Inverse and significant correlations between reactance and phase angle in the one-legged-support position were verified, in all adjustment models, with coefficient of determination varying between 62% and 91%. In the analysis of mediolateral velocity for the semi-tandem eyes closed position, positive correlation with TUG and an inverse correlation with bioimpedance parameters and pennation angle were observed, with coefficient of determination varying between 21% and 67%.

INTERPRETATION

The postural control is linearly related to bioimpedance parameters and functionality in the elderly. The assessment of balance can provide important information and furnishes useful insights for prevention and treatment strategies in elderly.

Simplified digital balance assessment in typically developing school children

BACKGROUND

Postural balance can be considered a conjoined parameter of gross motor performance. It is acquired in early childhood and honed until adolescence, but may also be influenced by various conditions. A simplified clinical assessment of balance and posture could be helpful in monitoring motor development or therapy particularly in pediatric patients. While analogue scales are considered unprecise and lab-based force-plate posturography lacks accessibility, we propose a novel kinematic balance assessment based on markerless 3D sensor technology.

RESEARCH QUESTION

Can balance and posture be assessed by tracking kinematic data using a single 3D motion tracking camera and are the results representative of normal motor development in a healthy pediatric cohort?

METHODS

A proprietary algorithm was developed and tested that uses skeletal data from the Microsoft Kinect™ V2 3D motion capture camera to calculate and track the center of mass in real time during a set of balance tasks. The algorithm tracks the distance of the COM traveled over time to calculate a balance score (COM speed). For this study, 432 school children aged 4-18 years performed 5 balance tasks and the resulting balance scores were analyzed and correlated with demographic data.

RESULTS

Preliminary experiments demonstrated that the system was able to reliably detect differences in COM speed during different balance tasks. The method showed moderate correlation with age and sex. Athletic activity positively correlated with balance skill in the age group < 8 years, but not in older children. Body mass appeared not to be correlated with balance ability.

SIGNIFICANCE

This study demonstrates that markerless 3D motion analysis can be used for the clinical assessment of coordination and balance and could potentially be used to monitor gross motor performance at the point-of-care.

Postural Control Performance on the Functional Reach Test: Validity of the Kids-Balance Evaluation Systems Test (Kids-BESTest) Criteria

OBJECTIVE

Evaluate the validity of the Kids-Balance Evaluation Systems Test (Kids-BESTest) clinical criteria for the Functional Reach Test (FRT) forward and lateral with laboratory measures of postural control in children with cerebral palsy (CP).

DESIGN

Psychometric study of face, concurrent, and content validity.

SETTING

Clinical laboratory.

PARTICIPANTS

Children (N=58) aged 7-18 years (ambulant CP n=17, typically developing [TD] n=41).

INTERVENTION

Not applicable.

MAIN OUTCOME MEASURES

Stability limits in standing were assessed using the Kids-BESTest items for FRT forwards (FRT_FORWARD), FRT lateral preferred (FRT_LATERAL(P)), and FRT lateral nonpreferred (FRT_LATERAL(NP)). Force platforms and kinematic markers were used to collect information on center of pressure (CoP) and joint movement during reach. Analyses included face validity (Kids-BESTest scores compared between CP and TD groups), concurrent validity (agreement between Kids-BESTest scores and digitally derived scores), and content validity (relations between Kids-BESTest scores with kinematic and CoP data).

RESULTS

Face validity of Kids-BESTest criteria was demonstrated with lower scores for CP compared to TD groups for FRT_FORWARD (P<.001) and FRT_LATERAL(NP) (P=.03) and equal scores for FRT_LATERAL(P) (P=.12). For concurrent validity, agreement between Kids-BESTest scores and digitally derived scores was good to excellent for FRT_{LATERAL(both P/NP)} (88%-100%) and good for FRT_FORWARD (86%-88%) for both groups. For content validity, the CP group Kids-BESTest scores were correlated with CoP-Range_FORWARD during FRT_FORWARD (ρ=0.68) and CoP-Range_LATERAL during FRT_LATERAL(NP) (ρ=0.57). For kinematic data, correlations were moderate-high between Kids-BESTest scores and range of hip flexion (ρ=0.51) and ankle plantar flexion (ρ=0.75) during FRT_FORWARD, and trunk lateral flexion (ρ=0.66) during FRT_LATERAL(NP).

CONCLUSION

The FRT_FORWARD demonstrated face, concurrent, and content validity. The FRT_{LATERAL(P/NP)} demonstrated concurrent validity, but partial face and content validity. To improve validity of Kids-BESTest FRT criteria, additional descriptors have been added under the scoring criteria to enable clinicians to quantify observed reach strategies.

[Postural control in adults. Influence of age and aerobic training.]

OBJECTIVE

The ability to control postural balance is essential to perform most of the activities of daily life, allowing you to maintain an active lifestyle, avoiding falls. However, aging-related changes in sensory systems, neural processing, information conduction, and musculoskeletal mechanics make postural control difficult in older adults. In the evaluation of posturo-graphic parameters, alterations are observed after physical exercise. The objective of this study focused on analyzing the possible influence of age on postural control in an adult population and comparing the differences in postural control due to the regular practice of aerobic physical activity.

METHODS

A cross-sectional study was carried out in 116 healthy adults, differentiating them between sedentary and sportsmen (cyclists and runners) and in two age groups (< and ≥ 65 years). Data were collected on the RMS amplitude (root-mean-square) in AP (antero-posterior) and ML (medio-lateral) and the RMS velocity obtained through a force platform in different support and vision conditions. SPSS 15.0 Software was used for the statistical treatment with a significance level of 5%. To compare the dependent variables between the different activity gropus, the t-test and the Mann-Witney were applied (p<0,05), while correlation análisys was applied to study the relationship of age in the postural parameters using p Pearson and Spearman test depending on the distribution of the data.

RESULTS

The results reaffirmed the negative influence of physiological aging on postural control mechanisms in the sedentary group, as well as a positive influence of the practice of aerobic exercise regardless of age, with an improvement in balance. More than half of the posturagraphic parameters (PP) were altered in sedentary subjects compared to athletes, who did not show alterations (p<0,05). The RMS-Velocity (mm/s) or distribution of displacement in standing over time, is the parameter with the greatest alteration in all the conditions analyzed (p<0,01), among sedentary subjects regardless of age, not suffering variations among athletes. In relation to the type of sport, we observed better results in cyclists compared to the sedentary group, with less alterations in all PP (RMS-ROM in AP, ML and RMS-Velocity) mainly for single-leg support on a hard surface and with eyes open as well as closed.

CONCLUSIONS

We can conclude that the practice of regular aerial exercise is a beneficial activity to improve postural control, preserve the deterioration of balance and prevent falls.

Hypoxia and standing balance

PURPOSE

Standing balance control is important for everyday function and often goes unnoticed until impairments appear. Presently, more than 200 million people live at altitudes > 2500 m above sea level, and many others work at or travel to these elevations. Thus, it is important to understand how hypoxia alters balance owing to implications for occupations and travelers. Herein, the influence of normobaric and hypobaric hypoxia on standing balance control is reviewed and summarized. As postural control relies on the integration of sensorimotor signals, the potential hypoxic-sensitive neurophysiological factors that contribute to balance impairments are also reviewed. Specifically, we examine how hypoxia impairs visual, vestibular, and proprioceptive cues, and their integration within subcortical or cortical areas.

METHODS

This systematic review included a literature search conducted via multiple databases with keywords related to postural balance, hypoxia, and altitude. Articles (n = 13) were included if they met distinct criteria.

RESULTS

Compared to normoxia, normobaric hypoxia worsened parameters of standing balance by 2-10% and up to 83 and 240% in hypobaric hypoxia (high-altitude and lab-based, respectively). Although balance was only disrupted during normobaric hypoxia at F_IO₂ <  ~ 0.15, impairments consistently occurred during hypobaric hypoxia at altitudes > 1524 m (~ F_IO₂ < 0.18).

CONCLUSION

Hypoxia, especially hypobaric, impairs standing balance. The mechanisms underpinning postural decrements likely involve alterations to processing and integration of sensorimotor signals within subcortical or cortical structures involving visual, vestibular, and proprioceptive pathways and subsequent motor commands that direct postural adjustments. Future studies are required to determine the sensorimotor factors that may influence balance control in hypoxia.

Hand grip strength is strongly associated with lower limb strength but only weakly with postural control in community-dwelling older adults

BACKGROUND

Hand grip strength is frequently used as a measurement of muscle strength, especially among older adults. Muscle strength is only one of the many components in postural control and it is currently unclear to what extent hand grip strength is associated with postural control. The aim was to analyze the association between hand grip strength and lower limb muscle strength, and postural control among older adults.

METHODS

Forty-five community-dwelling individuals over 70 years of age provided isometric hand grip strength and lower limb strength (including hip extension and abduction, knee flexion and extension, and ankle dorsiflexion and plantarflexion), as well as postural control measurements. In the latter, center of pressure excursions were recorded for quiet stance and limits of stability tests on a force plate. Orthogonal projection of latent structures regression models were used to analyze associations between hand grip strength and lower limb strength as well as postural control, respectively.

RESULTS

Lower limb strength explained 74.4% of the variance in hand grip strength. All lower limb muscle groups were significantly associated with hand grip strength. In a corresponding model, postural control measured with center of pressure excursions explained 20.7% of the variance in a statistically significant, albeit weak, model.

CONCLUSIONS

These results support that hand grip strength is a valid method to estimate lower limb strength among older adults on a group level. However, strength measurements seem insufficient as a substitute for measuring postural control, and therefore specific balance tests are necessary.

Vitamin D supplementation associated with 12-weeks multimodal training in older women with low bone mineral density: A randomized double-blind placebo-controlled trial

OBJECTIVE

To evaluate the influence of vitamin D supplementation with a multimodal exercise program on postural balance and muscle strength in older women with low bone mineral density (BMD) and vitamin D insufficiency.

METHODS

12-week, randomized, double-blind, placebo-controlled clinical trial. Total of 422 subjects were screened for participation, and 46 met the inclusion criteria. Those were randomized into an experimental group (EG; n = 23) and control group (CG; n = 23). At the time of enrollment, all subjects had low BMD, vitamin D insufficiency, and were not practicing resistance exercise. Muscle strength assessments were performed by the 30-s sit to stand test; 15-steps climbing test; handgrip dynamometer and knee muscle strength using an isokinetic dynamometer at 60°/sec. Postural balance was clinically evaluated by the MiniBESTest and by a force platform. Dynamic balance was assessed by standing up from a chair and walk over a step, using also a force platform.

RESULTS

In the EG, vitamin D levels increased in the post-treatment period (P < 0.001) whereas in CG levels remained unchanged (P = 0.86). Both groups improved muscular strength in the dynamometry isokinetic test: flexors PT/BW - right (P < 0.02) and left side (P < 0.04). In the dynamic postural balance during the task to step up over: the Lift Up Left was better in the CG (P = 0.01); the Moment Time left was better in the CG (P = 0.01); the Impact index left was better in the EG (P = 0.01). The Mini-BESTest - both groups improved the postural balance test (P < 0.001).

CONCLUSION

Vitamin D supplementation associated with multimodal exercise program did not augment muscle strength adaptation or postural balance in older women with low bone mineral density and vitamin D insufficiency.

Balance control in individuals with developmental coordination disorder: A systematic review and meta-analysis

BACKGROUND

Although it is recognized that the majority of children with developmental coordination disorder (DCD) have balance deficits, comprehensive insights into which balance domains are affected, are still lacking in literature.

RESEARCH QUESTION

To what extent is balance control deficient in individuals with DCD compared to controls?

METHODS

Pubmed, Scopus and Web of Science were systematically searched. Risk of bias was assessed with the Scottish Intercollegiate Guidelines Network checklist for case-control studies. Mean and standard deviations characterizing balance control were extracted to calculate standardized mean differences (SMD) and pooled, if possible, using Review Manager.

RESULTS

The results of 31 studies (1152 individuals with DCD, 1103 typically developing (TD) peers, mean age 10.4 years old) were extracted of which 17 were used for meta-analysis. The mean SMD for the balance subscale of the Movement Assessment Battery for Children was 1.63 (pooled 95 %CI =[1.30;1.97]), indicating children with DCD to perform significantly poorer than their TD peers. Force plate studies also revealed that children with DCD present with a larger sway path during bipedal stance with eyes closed (pooled mean SMD = 0.55; 95 %CI=[0.32;0.78]). Children with DCD tend to have direction-specific limited stability limits and task-independent delayed onset of anticipatory postural adjustments.

INTERPRETATION

Children with DCD perform poorer on different domains of balance compared to TD peers. Future research should focus on comprehensive balance assessment in these children, preferably using a longitudinal design.

Analysis of dynamic balance in preschool children through the balance beam test: A cross-sectional study providing reference values

BACKGROUND

dynamic balance (DB) is a complex ability at an early age and balance deficits are related to numerous disorders. There are several balance measures but wide variation in their use has restricted the capacity to synthesise references values. The main purpose of this study was to analyse the performance of the Balance beam test (BBT) in preschool children, according to age and sex providing BBT reference values, and also to analyse its reliability and validity.

RESEARCH QUESTION

could the BBT be a reliable test for measuring dynamic balance in preschool children?

METHODS

593 preschool children (3-6 years) participated in this study. The BBT was used to evaluate DB by measuring distance reached, time spent, and number of steps. Differences between sex and age groups were analysed using the Mann-Whitney U and Kruskal-Wallis tests. Test-retest reliability analysis was performed using intraclass correlation coefficients and the Bland-Altman graphic. Convergent validity was investigated with the Stork Balance stand test (SBST).

RESULTS

no significant differences were found for sex in any components of the BBT. Age had positive effects on BBT performance in distance (χ² = 63.474, p < 0.001), time (χ² = 46.441, p < 0.001), and step numbers (χ² = 40.967, p < 0.001). Younger children performed more poorly than older children. No significant interactions between age groups and sex were found. The BBT showed adequate validity and reliability.

SIGNIFICANCE

the reference values established for Spanish preschool children in the current study could be used to monitor DB development. It is necessary to take into account distance reached, time spent, and the steps taken to obtain a more precise measure of DB in this population.

Test-retest reliability of force plate-derived measures of reactive stepping

Characterizing reactive stepping is important to describe the response's effectiveness. Timing of reactive step initiation, execution, and termination have been frequently reported to characterize reactive balance control. However, the test-retest reliabilities of these measures are unknown. Accordingly, the purpose of this study was to determine the between- and within-session test-retest reliabilities of various force plate-derived measures of reactive stepping. Nineteen young, healthy adults responded to 6 small (~8-10% of body weight) and 6 large perturbations (~13-15% of body weight) using an anterior lean-and-release system. Tests were conducted during two visits separated by at least two days. Participants were instructed to recover balance in as few steps as possible. Step onset, foot-off, swing, and restabilization times were extracted from force plates. Relative test-retest reliability was determined through intraclass correlation coefficients (ICCs) and 95% confidence intervals (CIs). Absolute test-retest reliability was assessed using the standard error of the measurement (SEM). Foot-off and swing times had the highest between- and within-session test-retest reliabilities regardless of perturbation size (between-session ICC = 0.898-0.942; within-session ICC = 0.455-0.753). Conversely, step onset and restabilization times had lower ICCs and wider CIs (between-session ICC = 0.495-0.825; within-session ICC = -0.040-0.174). Between-session test-retest reliability was higher (ICC = 0.495-0.942) for all measures than within-session test-retest reliability (ICC = -0.040-0.753). Time to restabilization had the highest SEM, indicating the worst absolute reliability of the measures. These findings suggest multiple baseline sessions are needed for measuring restabilization and step onset times. The minimal detectable changes reported provide an index for measuring meaningful change due to an intervention.

Vertigo and Balance Disorders - The Role of Osteopathic Manipulative Treatment: A Systematic Review

BACKGROUND

Balance disorders are among the most frequent reasons for consultation and referral to specialist care. Osteopathic Manipulative Treatment (OMT) can influence the proprioceptive system by inducing alterations in the proprioceptive stimuli, hence affecting postural control.

OBJECTIVE

The present systematic review aimed to explore the effects of OMT in managing patients with vertigo and balance disorders.

METHODS

MEDLINE (PubMed), ScienceDirect, and Google Scholar were searched. Clinical trials and prospective observational studies were considered. Only studies that considered OMT as the main intervention, provided alone or combined with other interventions, were included. The methodological quality of the evidence was assessed with a modified version of the Newcastle-Ottawa Scale.

RESULTS

Five studies that enrolled a total of 114 subjects met our inclusion criteria. Overall, it has been observed that there is a positive effect on balance disorders through different outcomes in all of the included studies. Only two studies (9 subjects) mentioned low to moderate adverse events after OMT.

CONCLUSIONS

OMT showed weak positive effects on balance function, encouraging the connection of conventional medicine and evidence-based complementary medicine for integrative clinical practice and interprofessional work. However, full-sized adequately powered randomized trials are required to determine the effectiveness of OMT for vertigo and balance disorders.

Comparison of postural control in older adults under different dual-task conditions: A cross-sectional study

BACKGROUND

and purpose: Performing a cognitive task while maintaining postural stability, known as "dual-task" condition, can increase the cognitive demand and reduce the postural control capacity. The inability to allocate attention to postural control under dual-task conditions may lead to balance impairments, particularly in older adults. The present study aimed to compare the effects of different dual-task conditions of backward counting (BC) and visual attention (VA) on older adults' postural balance performance.

METHODS

Twenty asymptomatic volunteers (mean age: 70.4 ± 4.1 years) were recruited. Participants stood on a foam surface placed over a force plate, and displacement and sway velocity of their center of pressure (COP) in anterior-posterior (AP) and medial-lateral (ML) directions were recorded under three conditions: BC dual-task, VA dual-task (control of center of mass with a laser pointer), and quiet stance as the control task (CT).

RESULTS

Repeated measures ANOVA showed a significant difference in AP and ML sway velocities between conditions with p-values of 0.039 and 0.042, respectively. The LSD post-hoc test revealed that the BC task significantly increased AP sway velocity compared to the CT (p = 0.013), and the VA task significantly increased ML sway velocity compared to the CT (p = 0.034) and the BC tasks (p = 0.026). There were no statistically significant differences between conditions for ML (p = 0.058) and AP (p = 0.350) displacements and total sway velocity (p = 0.051).

CONCLUSION

Older adults' postural stability can be impaired under dual-task conditions and the present study revealed that various dual tasks increase postural sway in different directions.

The effect of dual-task conditions on gait and balance performance in children with cerebral palsy: A systematic review and meta-analysis of observational studies

Dual-task conditions are commonly experienced in daily routines. The aim of the present systematic review is to investigate the effect of dual-task conditions on gait and balance performance in children with cerebral palsy (CP) and to perform meta-analyses where applicable. Five databases, "ProQuest", "PubMed", "OTSeeker", "Scopus", and "PEDro" from the incipient date of databases up to Aug 24, 2020 were searched for studies focusing on the effects of dual-task conditions on gait and balance performance in children with CP. After removing irrelevant articles and applying inclusion and exclusion criteria, nine articles were included in the present systematic review and meta-analysis. The results of the meta-analysis showed that walking speed was slower during dual-task conditions compared to single-task conditions in children with CP (WMD = -0.29 m/s, 95% CI = -0.34, -0.24, P ≤ 0.001) and walking speed decreased in children with CP during dual-task conditions in comparison with the typical development (TD) control group (WMD = -0.19 m/s, 95% CI = -0.23 to -0.15, P ≤ 0.001). The results of subgroup analysis based on the type of task indicated that adding concurrent tasks to walking degrades walking speed under varied dual-task conditions. Additionally, theoretical synthesis of the literature demonstrated that other gait and balance variables are changed by performing cognitive and motor secondary tasks differently. Although these changes may be compensatory strategies to retain their stability, there was not sufficient evidence to reach a firm conclusion. Research gaps and recommendations for future studies are discussed.

Ankle muscle activation during the limits of stability test in subjects with chronic ankle instability

OBJECTIVE

To study postural control and muscle activity during the limit of stability test (LOS) in subjects with chronic ankle instability.

DESIGN

Observational study.

SETTING

University laboratory.

PARTICIPANTS

10 healthy subjects were included in the control group and 10 subjects in the CAI group (age between 18 and 30 years, with history of the multiple ankle "giving way" episodes in the last six months and score ≤24 in the Cumberland Ankle Instability Tool).

MAIN OUTCOME MEASURES

A computerized dynamic posturography equipment was used for assessing the LOS. The electromyography activity of tibialis anterior (TA), soleus (SOL), medial gastrocnemius (MG) and peroneus longus (PL) was registered.

RESULTS

Subjects with CAI had a greater activation in TA to forward (p < .01), forward affected (p = .001), backward affected (p = .007) and backward directions (p < .01); in PL to forward affected (p < .01) and affected directions (p = .001); in MG to forward (p = .023) and affected directions (p < .01) and in SOL to the affected direction (p = .009). We observed restricted excursions and less directional control in subjects with CAI.

CONCLUSIONS

Subjects with CAI exhibited poorer ability to move their center of gravity within stability limits. In addition, they have an altered ankle muscle activity during LOS test toward the affected ankle joint.