Measures Of Postural Stability Research Articles

High Load With Lower Repetitions vs. Low Load With Higher Repetitions: The Impact on Asymmetry in Weight Distribution During Deadlifting.

This study investigated weight distribution between the lower limbs using a symmetry index (SI) score of the vertical ground reaction forces (GRF) and measures of postural stability in high load/low repetition (termed “heavy”) and low load/high repetition (termed “light”) deadlifting. Ten participants performed two deadlift protocols with equal cumulative external load. These protocols were designed to represent standard high load/low repetition and low load/high repetition workouts; order was random and separated by 7 days. An effect of lifting condition (p = 0.023) and set number (p = 0.011) was observed such that lifts in the heavy condition were less symmetrical than those in the light condition and lifts became more symmetrical as set number increased. There was no effect of lift number on symmetry of force production (p = 0.127). Additional analysis revealed that center of pressure (COP) path length was greater during heavy lifts (p = 0.002) however COP range was unaffected suggesting controlled point of force application within the same boundaries regardless of lifting condition. As asymmetries have been previously associated with increased injury risk, greater training emphasis on the symmetrical performance of sub-maximal deadlifts should be considered to try to minimize the development of asymmetries.

The Effects of Cognitive Task and Change of Height on Postural Stability and Cardiovascular Stress in Workers Working at Height.

The purpose of the study was to analyze the effects of cognitive task and change of height on the postural stability and cardiovascular stress of at-height workers. The study included 32 healthy men aged 25–47. Due to the type of work performed, two groups were identified: at‒height workers, HW (n = 16), and office workers (mainly work at desk with a computer) OW (n = 16). The objective measures of postural stability (posturography) and cardiovascular stress (heart rate monitor) were evaluated for both groups at two different platform heights (ground level and 1 m above the ground) with or without cognitive task (backward counting). The increased height and the cognitive task were found to significantly affect measures of postural stability and cardiovascular stress. It was observed that in inexperienced OW employees, higher platform height and performing a cognitive task meant that posture stability significantly decreased, while cardiovascular stress and difficulties in maintaining balance increased. In HW group postural stability is less affected by distress conditions than in OW group.

The effect of Tai Chi exercise on postural time-to-contact in manual fitting task among older adults

BackgroundA fall would impact elderly population’s quality of life, which associate with diminished physical and psychological function, and can even be life-threatening. Tai Chi has been used to improve age-related postural instability in locomotion. However, it does not fully explain the mechanism of a lower risk of falling among the Tai Chi population compared to other healthy older adults. Research questionThe maintenance of postural stability is more complicated than minimizing postural movements. Postural time to contact is an important temporal measure of postural stability under fitting tasks, which might further clarify the benefits of long term Tai Chi exercise. MethodsParticipants were required to fit a block (90 × 90 mm) through two different openings (130 × 130 mm and 100 × 100 mm) at two different distances (arm’s length or 130 % of arm’s length). Kistler forceplate and Vicon system were used to collect center of pressure and kinematic data, respectively. Postural time to contact was used to assess instantaneous perturbation for postural system. ResultsTai Chi group exhibited significant longer postural time to contact in quiet standing and shorter postural time to contact in fitting tasks, expecting for close-small condition, compared to the brisk walking and sedentary groups (p < .05). In addition, both large and small opening condition, Tai Chi group showed a shorter postural time to contact than brisk walking and sedentary groups (p < .0001). SignificanceLong term Tai Chi exercise would promote the regulation of posture and decrease the postural constrain to increase the overall stability when performing fitting tasks. Therefore, Tai Chi exercise can be considered as a feasible method to enhance postural control and stability in older adult.

The Postural Stability Measures Most Related to Aging, Physical Performance, and Cognitive Function in Healthy Adults.

Background Different measures have been used to quantify body balance; some of which use technology to measure postural sway, others are physical performance or self-reported. However, there is little information on the best postural sway measures associated with aging, physical performance, and cognitive function measures. Objective To evaluate the relationship between postural sway measures and aging, physical performance, and cognitive function measures. Methods A total of 51 subjects (53% female, mean age 53.2 ± 21 years) participated in this cross-sectional study. The participants completed the Activities-specific Balance Confidence (ABC) Scale questionnaire, the Functional Gait Assessment (FGA), the Montreal Cognitive Assessment (MoCA) test, and gait speed. Afterward, the participants performed 8 balance exercises, and their postural sway was measured using a force plate. Spearman's rank correlation coefficient was used to examine the relationship between the study variables. Results Age was negatively associated with cognitive function, gait speed, ABC scores, and FGA scores. In addition, cognitive ability was associated positively with ABC scores (r = 0.38, p ≤ 0.01). Age, FGA scores, and gait speed were significantly associated with the postural sway of the AP direction in some exercises and in all exercises in the ML directions (p < 0.05). The cognitive function and ABC scores were significantly associated with only postural sway measures in the ML direction (p < 0.05). Conclusion The postural sway measures in the lateral direction had more and stronger associations with age, physical performance, and cognitive function measures compared to those in the AP direction.

Effect Of Kinesio Taping On Postural Control In Individuals With Chronic Ankle Instability

Chronic ankle instability (CAI), which is characterized by deficient postural control, may be improved through Kinesio Taping (KT) intervention. However, the effect of KT on postural control in individuals with CAI is controversial. PURPOSE: This study aimed to investigate the acute effect of KT on postural control through computerized dynamic posturography (CDP) and perceived sensation in individuals with CAI. METHODS: A total of 35 male adults with CAI participated in the study. Each participant received four random ankle taping, including KT, athletic taping (AT), sham taping (ST), and no taping (NT). Subsequently, a series of postural stability measurements was performed using CDP. The tests included sensory organization test (SOT), unilateral stance (US) test, limit of stability (LOS) test, motor control test, and adaption test (ADT). In addition, perception stability and comfort were measured through visual analogue scaling. One-way repeated measures analysis of variance was conducted to determine difference on postural control among KT, AT, ST, and NT. RESULTS: No significant difference was observed for parameters in SOT, US test, and LOS test among four taping. In the motor control test, the amplitude scaling scores of KT were 35.87% lower than NT (p<. 001) in forward-small slip and 21.58% lower than ST (p=.035) in backward-large slip. In ADT, sway energy scores were 7.59% greater in ST than this in AT (p=.028). For perception stability, KT was performed better than ST (p<.001) and NT (p<.001), and AT was performed better than ST (p=.001) and NT (p<.001). For perception comfort, KT was performed better than AT (p=.001) and NT (p=.031). CONCLUSIONS: KT and AT could not facilitate postural control for CAI individuals during static and voluntary measurements. However, they could provide effective support to cope with sudden perturbation. In addition, KT improved perception stability and comfort, whereas AT improved perception stability but provided the least comfort.

Postural Stability and Dynamic Balance in Adult Spinal Deformity: Prospective Pilot Study

We sought to evaluate dynamic balance and postural stability in patients with adult spinal deformity (ASD) compared with published age-matched normative data. Eleven patients with ASD were prospectively enrolled. Postural stability was tested using static and dynamic posturography; patients stood on a movable platform with an integrated force plate and performed standardized sensory organization testing (SOT), evaluating the influence of sensory processing on postural stability under 6 conditions, and motor control testing, assessing reflexive postural reactions to an external perturbation. Patient performance was compared with that of published age-matched controls. Quality of life metrics included scores on the Scoliosis Research Society-22 questionnaire, SF-36, and Morse Fall Scale. Correlations between postural stability and radiographic measurements were performed. ASD patients demonstrated significantly lower SOT scores (P ≤ 0.03) in 5 of 6 conditions tested and greater latency of limb movement during backward translation (P= 0.04) compared with controls. Lower SOT scores were associated with a history of falls. ASD patients who self-reported falling in the previous 6 months, when compared with nonfallers, demonstrated significantly lower SOT scores (P= 0.04) and significantly lower Scoliosis Research Society-22 self-image subscores (P= 0.003). Thoracic kyphosis and mediolateral sway (predictor of falls) were positively correlated in the eyes-open and eyes-closed conditions (P ≤ 0.04). ASD patients demonstrated impaired postural stability, diminished sensory integration, and delayed response to external perturbations compared with normal control data. Postural stability and quality of life metrics correlated with self-reported falls. These findings suggest that ASD patients have abnormal postural stability and may be at elevated risk of falls.

\u201cStudy protocol for the \u226565\u2009years NOrthern jutland Cohort of Fall risk Assessment with Objective measurements (the NOCfao study)\u201d

BackgroundAccidental falls are common among community-dwellers, probably due to the level of physical activity and impaired postural stability. Today, fall risk prediction tools’ discriminative validity are only moderate. In order to increase the accuracy, multiple variables such as highly validated objective field measurements of physical activity and impaired postural stability should be adressed in order to predict falls. The main aim of this paper is to describe the ≥65 years NOrthern jutland Cohort of Fall risk Assessment with Objective measurements (NOCfao) investigating the association between physical activity and impaired postural stability and the risk of fall episodes among community-dwelling older adults.MethodsThe study consists of a baseline session where the participants are asked to respond to three questionnaires, perform physical tests (i.e., measuring strength in the upper and lower extremities, balance, and walking speed), participate in an assessment of pain sensitivity, and to wear an ankle mounted pedometer for measuring physical activity for 5 days. Subsequently, the fall incidences and the circumstances surrounding the falls during the previous 1 to 2 months will be recorded throughout a one-year follow-up period.DiscussionThis study will add to the present-day understanding of the association between physical activity and impaired postural stability and the risk of fall episodes among community-dwelling older adults. These data will provide valid and reliable information on the relationship between these variables and their significance for community-dwelling older adults.Trial registrationClinicalTrials.gov identifier: NCT2995317. Registered December 13th, 2016.

Prediction of Individual Progression Rate in Parkinson's Disease Using Clinical Measures and Biomechanical Measures of Gait and Postural Stability.

Parkinson's disease (PD) is a common neurological disorder characterized by gait impairment. PD has no cure, and an impediment to developing a treatment is the lack of any accepted method to predict disease progression rate. The primary aim of this study was to develop a model using clinical measures and biomechanical measures of gait and postural stability to predict an individual's PD progression over two years. Data from 160 PD subjects were utilized. Machine learning models, including XGBoost and Feed Forward Neural Networks, were developed using extensive model optimization and cross-validation. The highest performing model was a neural network that used a group of clinical measures, achieved a PPV of 71% in identifying fast progressors, and explained a large portion (37%) of the variance in an individual's progression rate on held-out test data. This demonstrates the potential to predict individual PD progression rate and enrich trials by analyzing clinical and biomechanical measures with machine learning.

Agreement of Three Posturographic Force Plates in the Assessment of Postural Stability.

This study was designed to assess how the results obtained for three different posturographic platforms agreed with each other in an assessment of static postural stability. The study included 111 young healthy participants. A measurement of postural stability was made for each participant, with their eyes open and then closed, on each platform in a random order. The Romberg ratio, path length, and center of pressure (COP) area were analyzed. For all measures, significant differences (p < 0.05) were observed among the three force plates. The highest Spearman’s rank correlation was observed between Alfa vs. CQStab2P (0.20 to 0.38), and the lowest between Alfa vs. AccuGait (−0.19 to 0.09). Similar results were obtained for the concordance correlation coefficient (0.10 to 0.22 for Alfa vs. CQStab2P and −0.6 to 0.02 for Alfa vs. AccuGait). Bland-Altman analysis for values standardized (z-scores) against AccuGait indicated a low level of agreement between compared platforms, with the largest error between AccuGait vs. Alfa, and a slightly lower error between AccuGait vs. CQStab2P or Alfa vs. CQStab2P. The 95% limits of agreement ranged from 2.38 to 7.16 (Alfa vs. AccuGait), 2.09 to 5.69 (CQStab2P vs. AccuGait), and 1.39 to 7.44 (AccuGait vs. Alfa) in COP length with eyes open and COP length Romberg ratio, respectively. Special care is recommended when comparing values relating to COPs from different devices that are analyzed by different software. Moreover, unperturbed stance tests among young healthy adults can be questioned as a valid postural control parameter.

Acute Effect of Kinesiology Taping on Postural Stability in Individuals With Unilateral Chronic Ankle Instability.

BackgroundChronic ankle instability (CAI), which is characterized by deficient postural control, could be improved through kinesiology taping (KT). However, the effect of KT on postural control in CAI individuals is controversial. Therefore, this study aimed to investigate the acute effect of KT on postural control through computerized dynamic posturography (CDP) and self-perceived sensation in CAI individuals.MethodsParticipants with CAI received four different ankle treatments randomly, including KT, athletic taping (AT), sham taping (ST), and no taping (NT). A series of postural stability measurements was performed using CDP subsequently. The measurements included sensory organization test (SOT), unilateral stance (US), limit of stability (LOS), motor control test (MCT), and adaption test (ADT). In addition, self-perceived sensation was measured through visual analog scaling. Repeated measures analysis of variance was conducted to determine whether the difference among KT, AT, ST, and NT was significant; Bonferroni test was used for post hoc analysis.ResultsNo significant difference was observed for parameters in SOT, US, and LOS in four different taping treatments. In MCT, the amplitude scaling scores of KT were 35.87% significantly lower than that of NT [p < 0.001, 95% confidence interval (CI) = 0.548–1.795] in forward-small slip and 21.58% significantly lower than that of ST (p = 0.035, 95% CI = 0.089–3.683) in backward-large slip. In ADT, sway energy scores were 7.59% significantly greater in ST than in AT (p = 0.028, 95% CI = −8.343 to −0.320). For perceived stability, KT was significantly greater than ST (p < 0.001, 95% CI = 0.552–1.899) and NT (p < 0.001, 95% CI = 0.797–2.534), and AT was significantly greater than ST (p = 0.001, 95% CI = 0.423–2.246) and NT (p < 0.001, 95% CI = 0.696–2.852). For perceived comfort, KT was significantly greater than AT (p = 0.001, 95% CI = 0.666–3.196) and NT (p = 0.031, 95% CI = 0.074–2.332), and ST was significantly greater than AT (p = 0.007, 95% CI = 0.349–2.931).ConclusionKT and AT have limited effect to facilitate postural control for CAI individuals during SOT, US, and LOS. However, KT and AT could provide effective support to cope with sudden perturbation in MCT and ADT. Moreover, KT provided excellent perceived stability and comfort, whereas AT provided excellent perceived stability but least comfort.

Step Response of Human Motor System as a Measure of Postural Stability in Children

Postural sway is a product of the neuromuscular system that is commonly used in contemporary labs and clinics for the assessment of postural stability. In this study, we analyzed the transient responses of the neuromuscular system during the rise-on-toes (ROT) movement in eighteen 11 yrs old girls. Their center of pressure (COP) trajectories were recorded with standard force-platform during the transition from quiet stance to standing on toes. To assess the robustness of children's postural stability, we compared the ROT trajectories while the movement was performed with and without vision. Our results confirmed that the dynamic characteristics of the COP step response were significantly modified by visual feedback. In particular, the ROT test performed with eyes closed (EC) was characterized by a four-fold increase of COP chaotic oscillations at the target (tiptoe) position. This resulted in a substantial increase in the movement's index of difficulty (ID) thus to achieve adequate accuracy of the target-oriented movement the COP velocity was decreased accordingly. This inherent strategy of the brain controller allowed for precise positioning of the COP within the reduced size of the target. In conclusion, the dynamics of the ROT movement is always precisely adjusted to the stability of the upright posture, and thus, the dynamic characteristics of the COP step response are also sensitive measures of postural stability and the ROT can be recommended as a useful test for this assessment in the general population.

The Clinical Significance of the Failure to Perceive Vertigo in the Postcaloric Period Despite a Robust Caloric Response.

Purpose The purpose of this project was to explore the association between the perception of motion during caloric testing and two tasks associated with central vestibular processing: postural stability and visuospatial memory. Method This was a prospective study of 25 patients who were found to have nonvestibular etiologies of their symptoms and normal vestibular function test results and who underwent caloric testing with a mean maximum slow phase eye velocity for each irrigation of 15° or greater. Following each caloric irrigation, patients were asked whether they had any sensation of movement. Patients were grouped based on the presence or absence of motion during the caloric exam (motion perception vs. absent perception). Postural stability was assessed using computerized dynamic posturography, and visuospatial memory was assessed using a memory match card game application. Results There were no significant differences between groups on any measures of peripheral vestibular function. However, the Absent Perception Group showed greater postural instability during Condition 5 of posturography and performed significantly worse on a task of visuospatial working memory. Both age and absence of motion perception predicted abnormal performance on measures of postural stability and visuospatial working memory. Conclusions There appears to be clinical implications to a lack of motion perception during the caloric exam in patients with an otherwise normal peripheral vestibular system. Based on the current findings, we are unable to determine whether differences in postural stability and visuospatial memory were due to age or a central vestibular processing deficit.

Military-Specific Normative Data for Cognitive and Motor Single- and Dual-Task Assessments for Use in Mild Traumatic Brain Injury Assessment.

Military personnel and civilian athletes are both at risk for mild traumatic brain injury. However, these groups are unique in their training and typical daily activities. A fundamental gap in the evaluation of military personnel following mild traumatic brain injury is the lack of military-specific normative reference data. This project aimed to determine if a separate normative sample should be used for military personnel on their performance of the Cleveland Clinic Concussion application and a recently developed dual-task module. Data were collected from healthy military personnel (n=305) and civilians (n=281) 18 to 30years of age. Participants completed the following assessments: simple and choice reaction time, Trail Making tests A&B, processing speed test, single-task postural stability, single-task cognitive assessment, and dual-task assessment. Civilian participants outperformed military service members on all cognitive tasks under single- and dual-task conditions (P≤0.04). The military group outperformed civilians on all postural stability tasks under single- and dual-task conditions (P≤0.01). Differences in cognitive performance and postural stability measures may be influenced by demographic differences between military and civilian cohorts. Thus, military-specific normative datasets must be established to optimize clinical interpretation of Cleveland Clinic Concussion assessments.

Absolute and relative reliability of several measures of static postural stability calculated using a GYKO inertial sensor system

The aim of this study was to analyse absolute and relative reliability of a number of postural static stability measures obtained from a GYKO inertial sensor system in young adults. The study examined 29 healthy non-athlete young adults. A test was performed for 30 s while standing on one foot, without moving, with eyes open and arms relaxed along the sides of the body. The examinations were performed twice, with a one-week interval. Relative reliability was measured using the intraclass correlation coefficient (ICC) and the 95% confidence interval (95% CI), whereas the absolute reliability was evaluated based on the standard error of measurement (SEM) and the minimal detectable change (MDC). The results of this study showed moderate to good relative reliability scores for all the postural stability measures, with ICC values ranging from 0.62 to 0.70. For most of the analysed variables, SEM% ranged from ca. 10 to 14%. Relatively high SEM% values were obtained only for two variables (Area, Convex Hull Area). The low costs of GYKO inertial sensor systems, the fast and easy installation, the mobility and high reliability of the measurement of postural stability show that it can be effective alternative to stabilographic platforms.

Comparison of core neuromuscular control and lower extremity postural stability in athletes with and without shoulder injuries

BackgroundThe kinetic chain theory is widely used as a rationale for the inclusion of core stability training in athletes. Core stability (muscle capacity and neuromuscular control) impairments may result in less than optimal performance and abnormal force dissipation to the shoulder complex that could lead to shoulder injuries. However, a paucity of literature exists to support this relationship, and no previous studies have investigated the relationship between isolated core neuromuscular control and shoulder injuries. Additionally, lower extremity postural stability has been associated with athletic function and may also be associated with shoulder injuries. The purpose of this study was to compare biomechanical measures of isolated core neuromuscular control and lower extremity postural stability between athletes with and without non-traumatic shoulder injuries. MethodsEighty athletes (55 males, age: 21.2 ± 3.3 years, 40 with a current shoulder injury) completed biomechanical measures of isolated core neuromuscular control and lower extremity postural stability. Athletes were matched by age, gender, body mass index, and sport type. MANOVAs were used to assess differences between measures of core neuromuscular control and lower extremity postural stability between groups. FindingsThere were no statistically significant differences between athletes with and without shoulder injuries for the static core neuromuscular control measures, F(4,75) = 0.45, P = 0.78, η2 = 0.02; dynamic core neuromuscular control measures, F(4,75) = 0.81, P = 0.52, η2 = 0.04; or lower extremity postural stability measures, F(8,61) = 0.85, P = 0.56, η2 = 0.10. InterpretationAlthough core stability is widely incorporated in rehabilitation of athletes with shoulder injuries, athletes with current non-traumatic shoulder injuries may not present with impairments in core neuromuscular control or lower extremity postural stability.

Monopodal Postural Stability Assessment by Wireless Inertial Measurement Units Through the Fast Fourier Transform.

(1) To describe the fast Fourier transform (FFT) multijoint as monopodal postural stability measurement in well-trained athletes, (2)to compare the within-subject FFT between laterality, joints, and body segments, and (3)to establish the within- and between-subject relationship between joints. Twelve national-level basketball players participated voluntarily in this investigation. The participants performed two 60-second repetitions of a monopodal stability test (1 repetition with each lower limb), separated by 3 minutes of active recovery. All tests were recorded by 4 WIMU PRO™ inertial devices located on the ankle, knee, lumbar spine, and thoracic spine. The main variable was total acceleration, where the FFT was applied. The higher instability results were found in the ankle and in the nondominant lower limb (dominant = 1.131 [0.122] a.u. (arbitrary units); nondominant = 1.141 [0.172] a.u). In the body segment analysis, the greater percentage of differences (%diff) were shown between lumbar spine and knee in the dominant (%diff = -2.989%; d = 0.87) and nondominant (%diff = -3.243%; d = 0.90) lower limb. Finally, very large between-subjects variability was found in all joints and body segments. The described protocol is proposed for monopodal postural stability assessment, being useful to provide information about the stability of joints and the body segment between joints. Besides, a within-subject analysis is recommended, and the FFT calculation will enable a linear analysis of each test.

Normative Data Set of SWAY Balance Mobile Assessment in Pediatric Athletes.

To examine and describe normative values for an objective, mobile measure of postural stability commonly used in concussion assessments, SWAY Balance (SWAY Medical, Tulsa, Oklahoma). Retrospective analysis of baseline balance assessments in a healthy pediatric population. Baseline assessments completed by certified athletic trainers at an outpatient concussion center or sports medicine offices in Philadelphia, PA and surrounding suburban Pennsylvania and New Jersey or during an athletic trainer's baseline assessment of collegiate athletes at a National Collegiate Athletic Association (NCAA) Division-II University in Fort Lauderdale, FL. Test results of a sample of 466 athletes aged 5 to 18 years were included. The SWAY Balance test was administered using a mobile device on all participants as part of a standard preseason, baseline evaluation, following the standard evaluation protocol. Baseline SWAY Balance mobile assessment balance and reaction time scores, age and sex effects, were examined. Normative scores are described, with results stratified into 4 age groups (5-9, 10-12, 13-17, and 18 years old). Balance scores, overall and within each individual stance score, improved with the age of the participants. Sex effects on balance were only seen in single-leg stances, with females outperforming males. Reaction time was found to be faster in males and improved with age, peaking at 13 to 17 years old and slowing in 18-year-olds. Normative, age-specific SWAY Balance test results provided are of clinical use as references in the concussion assessments of pediatric athletes.

Limited evidence of physical therapy on balance after stroke: A systematic review and meta-analysis.

BackgroundStroke results in balance disorders and these directly affect autonomy and quality of life. The purpose of this systematic review and meta-analysis was to determine the efficacy of physical therapy (PT) on balance and postural control after stroke.MethodsWe included all randomized controlled trials assessing the efficacy of PT on balance and postural control in adult patients after stroke without language restriction. Medline, Embase/Scopus, Cochrane Central Register of Controlled Trials, PEDro, Pascal, and Francis databases were searched until January 2019. Primary outcomes were balance (Berg Balance scale and Postural Assessment Scale for Stroke) and postural control with postural deviation or stability measurement in sitting or standing static evaluation. A pair of independent reviewers selected studies, extracted data, and assessed risk of bias. Meta-analyses with subgroups (categories of PT, time post-stroke, and lesion location) and meta-regression (duration of PT) were conducted.ResultsA total of 145 studies (n = 5912) were selected from the 13,123 records identified. For balance, evidence was found in favor of the efficacy of functional task-training alone (standardized mean difference 0.39, 95% confidence interval [0.09; 0.68], heterogeneity I2 = 63%) or associated with musculoskeletal intervention and/or cardiopulmonary intervention (0.37, [0.19; 0.55], I2 = 48%), electrostimulation (0.91, [0.49; 1.34], I2 = 52%) immediately after intervention, compared to sham treatment or usual care (ST/UC). For postural deviation eyes open, assistive devices were more effective than no treatment (-0.21, [-0.37; -0.05], I2 = 0%) immediately after intervention; for postural stability eyes open, functional task-training and sensory interventions were more effective than ST/UC (0.97, [0.35; 1.59], I2 = 65% and 0.80, [0.46; 1.13], I2 = 37% respectively) immediately after intervention.ConclusionsFunctional task-training associated with musculoskeletal intervention and/or cardiopulmonary intervention and sensory interventions seem to be immediately effective in improving balance and postural stability, respectively. The heterogeneity of PT and the weak methodological quality of studies limited the interpretation and the confidence in findings.

Postural Instability in Subjects With Usher Syndrome.

This study investigated postural performances and vestibular impairment in Usher patients. The three groups studied were: 11 patients with Usher type I (with visual and vestibular impairment), 14 patients with Usher type II (with only visual impairment), and 14 healthy control subjects. Postural stability was measured with a Framiral Multitest Equilibre platform with three visual conditions: eyes open (EO), eyes closed (EC), and vision disturbed by optokinetic stimulation (OPT), and two different postural conditions: stable or unstable platform. The surface and mean velocity of the center of pressure displacement (CoP) were measured and a postural instability index (PII) was calculated. Usher type I and II patients were more unstable than control subjects, but only for the unstable platform. Patients with Usher type I (with severe vestibular impairment) were also significantly more unstable than patients with Usher type II (with normal vestibular function) on the unstable platform. The severity of the vestibular impairment was correlated with the surface of the CoP displacement. We suggest that poor postural control of Usher patients is due to the abnormalities in their visual and, when defective, vestibular inputs. Measurements of postural stability on an unstable platform can distinguish type I from type II Usher patients. We emphasize the importance of multisensory evaluation in these patients to guide development of personalized visuo-vestibular rehabilitation techniques to improve their postural stability and improve their quality of life.

Toward more reliable stability measurements in stance: recommendations for number of measurements, foot position and feedback -- a cross-sectional study among servicemen

BackgroundIn the military, insufficient postural stability is a risk factor for developing lower extremity injuries. Postural stability training programs are effective in preventing these injuries. However, an objective method for the measurement of postural stability in servicemen is lacking. The primary objective of this study was to assess the influence of the number of repetitions, different foot positions and real-time visual feedback on postural stability, as well as their effects on the intrasession reliability of postural stability measurements in servicemen. The secondary objective was to assess the concurrent validity of the measurements.MethodsTwenty healthy servicemen between 20 and 50 years of age and in active duty were eligible for this quantitative, cross-sectional study. The measurements took place on a force plate, measuring the mean velocity of the center of pressure. The participants were asked to stand as still as possible in three different foot positions (wide stance, small stance, and on one leg), five times each for 45 s each time, and the measurements were performed with and without real-time visual feedback.ResultsWe observed a significant main effect of foot position (P < 0.001), but not of visual feedback (P = 0.119) or repetition number (P = 0.915). Postural stability decreased in the more challenging foot positions.The ICC estimates varied from 0.809 (one repetition in wide stance) to 0.985 (five repetitions on one leg). The common variance (R2) between different foot positions without feedback varied between 0.008 (wide stance) and 0.412.ConclusionsTo yield reliable data, wide-stance measurements should be conducted three times, and small-stance measurements and measurements on one leg should be conducted two times.The scores of a measurement in a particular foot position cannot predict the scores of measurements in other foot positions.