Assessment Of Balance Control Research Articles

A highly challenging balance training intervention for people with multiple sclerosis: a feasibility trial

BackgroundBalance training interventions with a gradual progression of difficulty and highly challenging tasks designed specifically for people with multiple sclerosis (MS) are rare. The objective was to adapt a balance training intervention originally developed for Parkinson’s disease through a co-design process and then conduct a pilot trial in MS to evaluate the feasibility of a large, full-scale study.MethodsTwelve people with MS with mild to moderate overall MS-disability were included in this single-group feasibility trial. Participants received one-hour training sessions twice or three times weekly for 10 weeks. The assessment included tests of physical and cognitive functioning and patient-reported quality of life-related outcomes. Data on feasibility aspects were collected at baseline and follow-up assessments and three times during the intervention period to inform the recruitment process, as well as to monitor retention and inclusion rates, study procedures, intervention delivery, and dynamic changes in the selected potential outcome measures. Progression criteria were used to determine whether to proceed to a full-scale trial. Descriptive statistics were used to present the data.ResultsOut of six progression criteria, only retention and attendance at training sessions were not met. Reasons reported for not completing the intervention period mainly depended on external circumstances beyond the control of the study. In contrast, study procedures, intervention delivery, and intervention content (progression, adjustment, and control of challenge level of exercises) were considered feasible for a future, full-scale trial. The Mini-BESTest, which was used for the assessment of balance control, was considered suitable as the primary outcome in a full-scale trial with no ceiling or floor effects. Further, the Mini-BESTest showed a positive trend in outcome response with a median difference of 3.5 points between baseline and follow-up assessments. The power calculation performed suggests a feasible number of participants for recruitment.ConclusionsOverall trial aspects and intervention delivery were deemed feasible for a full-scale trial, but adjustments are needed to increase retention and attendance.

32. An introductory investigation of postural balance strategy reliance using a novel force plate analysis technique among common degenerative spinal pathologies

<h3>BACKGROUND CONTEXT</h3> There has been growing interest in functional outcomes following surgical treatments for degenerative spinal pathologies (DSP). Objective functional measures provide unbiased metrics for assessing both patient's individual baseline functional deficits and postoperative recovery. Balance is a key component to assessment of spine treatment outcomes and has been objectively shown to improve postoperatively among many common DSP. There has, however, been a fundamental lack of understanding of exactly how DSP affects standing postural control and whether it is also impacted by surgical treatments. A novel technique was recently developed using a single force plate which provides direct assessment of balance control and quantifies balance strategy reliance but has yet to be applied to DSP. <h3>PURPOSE</h3> To provide preliminary data on balance strategy reliance among DSP using a novel force plate analysis and to compare to health (H) controls. <h3>STUDY DESIGN/SETTING</h3> Retrospective review at a single institution. <h3>PATIENT SAMPLE</h3> DSP patients 122 adult spinal deformity (ASD, 85F/36M, 61yr, 1.6m, 77kg), 81 degenerative lumbar spondylolisthesis (DLS, 51F/31M, 60yr, 1.7m, 81kg), 140 lumbar spinal stenosis (LSS, 40F/100M, 54yr, 1.7m, 92kg), 106 cervical spondylotic myelopathy (CSM, 58F/48M, 62yr, 1.7m, 82kg), and 61 H (37F/24M, 40yr, 1.7m, 72kg). <h3>OUTCOME MEASURES</h3> PROMs VAS pain, ODI/NDI; balance strategy reliance data. <h3>METHODS</h3> Subjects completed 60-second quiescent standing tests with eyes open and arms at their sides while on a force plate. Center of pressure (COP) range of sway (ROS) was used to assess baseline balance deficits. Balance strategy reliance was assessed using force intersection point (FIP) analysis which quantifies degree of balance activation by sway frequency ∼1.75Hz relates to knee and hip involvement at smaller amplitudes. FIP amplitude is reported as % height of the center of mass. <h3>RESULTS</h3> PROMs indicated DSP patients had severe VAS pain (Neck (CSM) 4.8, Back >6.0, Leg >4.0) and disability (ODI/NDI >40). DSP patients all exhibited significantly elevated ROS (mean coronal=31mm, mean sagittal=45mm) compared to H (18mm and 32mm respectively). ASD had significantly lower FIP at 3.5Hz (23%, p=0.003) and 4.0Hz (17%, p=0.029) compared to H (32% and 24%). DLS had significantly lower FIP at 3.0Hz (33%, p=0.036) than H (38%). LSS had significantly lower FIP in 3.5Hz (25%, 0.018), 4.0Hz (18%, p=0.030), and 4.5Hz (14%, p=0.005) than H (32%, 24%, 22% respectively). CSM had significantly lower FIP at 2.5Hz (49%, p=0.027), 3.0Hz (33%, p=0.011), and 4.5Hz (14%, p=0.003) than H (53%, 38%, and 22% respectively). Averages in low frequency FIPs tended to be greater than H and averages in high frequency FIPs tended to be less than H. <h3>CONCLUSIONS</h3> FIP provides novel insight into balance deficits among DSP patients which no method has previously quantified and negates issues associated with voluntary shifts in sway by providing simulatenous data across a range of relevant frequencies. Symptomatic DSP patients exhibited differences in balance strategy reliance compared to H with a general increase in low frequency, ankle-based reliance and a decrease in higher frequency, knee- and hip-based reliance. FIP analysis data is simple to implement clinically with a single force plate and may serve as a future screening tool for DSP screenings. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.

Impact of Gender, Change of Base of Support, and Visual Deprivation on Postural Balance Control in Young, Healthy Subjects

Background: Vision, vestibular sense, proprioception and muscle strength are required to maintain balance. However, gender could also play a crucial role in postural sway. Objectives: This study was used to examine (i) the impact of gender, surface type, and vision on postural sway; (ii) the effects of gender and vision on the limb symmetry of postural sway; and (iii) to understand the effects of gender, stance, surface type and vision on the alterations of dynamic postural sway alterations. Methods: This was a cross-sectional study in which young, healthy men (n = 15) and women (n = 12) underwent a balance control assessment using a force plate (SATEL, 40 Hz). Postural stances were evaluated in different conditions: Opened eyes (EO) and closed eyes (EC), on different surface foam vs. firm, a dominant leg stance (DL) vs. a non-dominant leg stance (NDL), and a mediolateral stance (ML) vs. an anteroposterior stance (AP). The mediolateral sway (ML sway), anteroposterior sway (AP sway), and sway area were calculated from the centre of pressure displacements. Results: ML sway, AP sway and sway area increased when eyes were closed (P &lt; 0.000). Foam surface perturbs balance control more than firm surface under EO and EC conditions for both genders, as observed in the AP sway curve (P &lt; 0.000). A functional symmetry exists between the DL and NDL for all sway parameters: The ML sway, AP sway, and sway area (P = 0.720; P = 0.292; P = 0.954). The AP stance is more stable for the ML sway than the ML stance for both genders (P &lt; 0.001). For the AP sway, the ML stance is more stable than the AP sway AP direction stance for both genders (P &lt; 0.001). Women were significantly more stable than men in the ML stance when vision was absent (P &lt; 0.01). Conclusions: Postural sway was altered more significantly on a foam surface than on a firm surface and symmetry between the DL and NDL was observed. Furthermore, we concluded that women have better dynamic balance control than men.

Concurrent validity of the inertial sensors for assessment of balance control during quiet standing in patients with chronic low back pain and asymptomatic individuals

The objective was to investigate the concurrent validity of inertial sensors for measuring balance control in patients with chronic low back pain and asymptomatic individuals. Thirty-nine patients with chronic low back and 39 age- and sex-matched asymptomatic individuals were included. Balance control analysis was performed in quiet standing with two inertial sensors positioned at the lumbar region and the sternum and compared to the results of a force plate. The variables analysed with either device were Root Mean Square (RMS), index of smoothness (JERK), trajectory length (PATH) and area (AREA). Spearman’s correlation coefficient investigated the correlation. Patients with chronic low back pain showed moderate correlation with the inertial sensor positioned on the lumbar for RMS (r s = 0.59; p < 0.01), PATH (r s = 0.42, p = 0.01) and AREA (r s = 0.59; p < 0.01) and weak correlation with the inertial sensor positioned on the sternum for PATH (r s = 0.36, p = 0.04). The asymptomatic group showed statistically significant correlations for RMS for the lumbar (r s = 0.38; p = 0.03) and sternum inertial sensor (r s = 0.42; p = 0.02). Inertial sensors showed weak to moderate correlations compared to data obtained from a force plate.

The relationships between knee extensors/ flexors strength and balance control in elite male soccer players

BackgroundStrength and balance are important factors for soccer players to be successful. This study’s aim was to determine the relationship between lower-limb muscle strength and balance control in elite male soccer players (n = 77).MethodsConcentric isokinetic strength (peak torque of quadriceps (PT-Q) and hamstrings (PT-H), hamstrings/quadriceps (H/Q) ratio) was measured for the dominant and non-dominant leg at angular velocities of 60°s−1and 240°s−1, as well as the total work for extensors (TW-Q) and flexors (TW-H) for both legs (at an angular velocity of 240°s−1only). Balance score (BAL score) was used for unilateral assessment of balance control using a Delos Postural System Test measurement tool. Hierarchical multiple regression analyses were performed to predict balance control using isokinetic knee strength performance for dominant and non-dominant legs.ResultsFinal modelling included peak torque of hamstrings at 240°s−1 and peak torque of the quadriceps at 240°s−1 for the non-dominant leg (R2 = 19.6%; p ≤ 0.001) and only peak hamstring torque at 240°s−1 for the dominant leg (R2 = 11.3%; p = 0.003) as significant predictors of balance score.ConclusionFindings indicate that balance control is widely influenced by peak hamstring torque and peak quadriceps torque at high angular velocity particularly in the non-dominant leg i.e., the supporting leg in soccer players.

Impact of Gender, Change of Base of Support, and Visual Deprivation on Postural Balance Control in Young, Healthy Subjects

Background: Vision, vestibular sense, proprioception and muscle strength are required to maintain balance. However, gender could also play a crucial role in postural sway. Objectives: This study was used to examine (i) the impact of gender, surface type, and vision on postural sway; (ii) the effects of gender and vision on the limb symmetry of postural sway; and (iii) to understand the effects of gender, stance, surface type and vision on the alterations of dynamic postural sway alterations. Methods: This was a cross-sectional study in which young, healthy men (n = 15) and women (n = 12) underwent a balance control assessment using a force plate (SATEL, 40 Hz). Postural stances were evaluated in different conditions: Opened eyes (EO) and closed eyes (EC), on different surface foam vs. firm, a dominant leg stance (DL) vs. a non-dominant leg stance (NDL), and a mediolateral stance (ML) vs. an anteroposterior stance (AP). The mediolateral sway (ML sway), anteroposterior sway (AP sway), and sway area were calculated from the centre of pressure displacements. Results: ML sway, AP sway and sway area increased when eyes were closed (P &lt; 0.000). Foam surface perturbs balance control more than firm surface under EO and EC conditions for both genders, as observed in the AP sway curve (P &lt; 0.000). A functional symmetry exists between the DL and NDL for all sway parameters: The ML sway, AP sway, and sway area (P = 0.720; P = 0.292; P = 0.954). The AP stance is more stable for the ML sway than the ML stance for both genders (P &lt; 0.001). For the AP sway, the ML stance is more stable than the AP sway AP direction stance for both genders (P &lt; 0.001). Women were significantly more stable than men in the ML stance when vision was absent (P &lt; 0.01). Conclusions: Postural sway was altered more significantly on a foam surface than on a firm surface and symmetry between the DL and NDL was observed. Furthermore, we concluded that women have better dynamic balance control than men.

Quantitative Static and Dynamic Assessment of Balance Control in Stroke Patients.

In patients with stroke, damage to the central nervous system (CNS) can affect the postural stability and increase the risk of falling. Therefore, accurately assessing the balance is important to understand the type, extent, and causes of balance deficit, and to identify individualized interventions. Clinical assessment methods for balance function can be broadly divided into observation, scale assessment, and balance instrument testing. Here, a clinical protocol is presented for static and dynamic balance assessment in stroke patients, which includes three semiquantitative balance function scale assessments (i.e., Berg Balance Scale, Timed Up and Go Test, and Fugl-Meyer Assessment) and three quantitative instrumental balance evaluation (i.e., Stability Assessment Module, Proprioceptive Assessment Module, and Limit of Stability Module). It is recommended that clinicians consider the use of both classic clinical balance scales and instrumental balance measurements when assessing stroke patients to improve the accuracy of assessments, leading to a better individualized treatment plan.

Reliability and practical clinical application of an accelerometer-based dual-task gait balance control assessment

BackgroundGait balance control assessment using whole body center of mass (COM) kinematic measures in concussed individuals reveals persistent balance deficits up to two months post-injury. A reliable and clinically practical gait balance control assessment leveraging similar kinematic measures is necessary to improve concussion assessment and management. Research questionCan peak accelerations collected during a dual-task (DT) gait assessment from a single low back placed accelerometer be measured reliably on different days, by different raters, in different environments, and be practically applied in a Division One (D1) athletics program? MethodsA single accelerometer placed on the low back over the L5 vertebra was utilized with a DT gait analysis protocol. Twenty (10 F) healthy participants performed the assessment in a laboratory and non-laboratory environment, on two separate days, and with two different raters. Eight gait event specific peak accelerations along three orthogonal axes were collected. In addition, data were collected from a cohort of 14 D1 female soccer players during a single assessment to explore the practical clinical application. ResultsCronbach’s α values for the eight metrics ranged from 0.881 to 0.980 and ICC values from 0.868 to 0.987. Average assessment time for the 14 D1 female athletes was 8.50 ± 0.58 min, and significant differences between walking conditions were identified for Vert Accel 1 (p < .01), Vert Accel 2 (p = .01), and A-P Accel (p < .01). SignificanceHigh Cronbach’s α and ICC values coupled with a short assessment time and sensitivity to differences in gait balance control indicate our testing apparatus and protocol are both reliable and clinically practical. Additionally, gait event specific peak accelerations from a single accelerometer can detect subtle changes in gait balance control and may facilitate improvements in sport-related concussion diagnosis and return to activity decision making.

Towards Using the Instrumented Timed Up-and-Go Test for Screening of Sensory System Performance for Balance Control in Older Adults.

Background: Decreasing performance of the sensory systems’ for balance control, including the visual, somatosensory and vestibular system, is associated with increased fall risk in older adults. A smartphone-based version of the Timed Up-and-Go (mTUG) may allow screening sensory balance impairments through mTUG subphases. The association between mTUG subphases and sensory system performance is examined. Methods: Functional mobility of forty-one community-dwelling older adults (>55 years) was measured using a validated mTUG. Duration of mTUG and its subphases ‘sit-to-walk’, ‘walking’, ‘turning’, ‘turn-to-sit’ and ‘sit-down’ were extracted. Sensory systems’ performance was quantified by validated posturography during standing (30 s) under different conditions. Visual, somatosensory and vestibular control ratios (CR) were calculated from posturography and correlated with mTUG subphases. Results: Vestibular CR correlated with mTUG total time (r = 0.54; p < 0.01), subphases ‘walking’ (r = 0.56; p < 0.01), and ‘turning’ (r = 0.43; p = 0.01). Somatosensory CR correlated with mTUG total time (r = 0.52; p = 0.01), subphases ‘walking’ (r = 0.52; p < 0.01) and ‘turning’ (r = 0.44; p < 0.01). Conclusions: Supporting the proposed approach, results indicate an association between specific mTUG subphases and sensory system performance. mTUG subphases ‘walking’ and ‘turning’ may allow screening for sensory system deterioration. This is a first step towards an objective, detailed and expeditious balance control assessment, however needing validation in a larger study.

Gait and its components in typically developing preschoolers

ObjectivesTo determine whether key spatio-temporal components of gait can be identified in children who are preschoolers. Subsequently the obtained components were correlated to results of functional balance tests to determine which of them are related to balance control. MethodsThirty-three typically developing children performed gait on treadmill at three speeds (range 2–4.5km/h), the Pediatric Balance Scale (PBS) and the Timed Up and Go test (TUG). Principal component analysis (PCA) with varimax rotation was performed to detect relations between means and variability of step time, −length and −width, walking speed, age, BMI and leg length. Pearson correlation coefficients between the principal components and z-scores of the PBS and TUG were calculated. ResultsPCA revealed three principal components. The first component, maturation, showed high loadings for mean step length (0.911), age (0.897), walking speed (0.895), leg length (0.874) and step time variability (−0.672) explaining 37.57% of the variance. The second component, variability of gait, loaded with step length variability (0.819) and step width variability (0.818), explaining 18.02% of the variance. The third component, robustness, showed high loadings for mean step time (0.729), BMI (0.668) and mean step width (0.521), explaining 13.89% of the variance. A significant weak correlation was found between robustness and z-scores of the PBS (r=0.230, p=0.005). ConclusionsIt seems that the key spatio-temporal component robustness is complementary to functional balance tests, suggesting its relevance in the assessment of balance control in preschoolers.

Automatic Segmentation of Stabilometric Signals Using Hidden Markov Model Regression

Posture analysis in quiet standing is an essential element in evaluating human balance control. Many factors enhance the human control system’s ability to maintain stability, such as the visual system and base of support (feet) placement. In contrast, many neural pathologies, such as Parkinson’s disease (PD) and cerebellar disorder, disturb human stability. This paper addresses the problem of the automatic segmentation of stabilometric signals recorded under four different conditions related to vision and foot position. This is achieved for both control subjects and PD subjects. A hidden Markov model (HMM)-regression-based approach is used to carry out the segmentation between the different conditions using simple and multiple regression processes. Twenty-eight control subjects and thirty-two PD subjects participated in this study. They were asked to stand upright while recording stabilometric signals in mediolateral and anteroposterior directions under two permutations: feet apart and together with eyes open or closed. The results show high values for the correct segmentation rates, up to 98%, for the separation between the different conditions. The present findings could help clinicians better understand the motor strategies used by the patients during their orthostatic postures and may guide the rehabilitation process. The proposed method compares favorably with standard segmentation approaches. Note to Practitioners —In this paper, the problem of human balance control assessment is analyzed through the segmentation of the multidimensional time series of the center of pressure (CoP) displacement measurements during orthostatic postures of healthy and Parkinsonian subjects. The proposed model for automatic temporal segmentation is a specific statistical latent process model that assumes that the observed stabilometric sequence is governed by a sequence of hidden (unobserved) states or conditions. More specifically, the proposed approach is based on a specific multiple regression model that incorporates a hidden Markov process that governs the switching from one condition to another over time. The model is learned in an unsupervised context by maximizing the observed data log-likelihood via a dedicated expectation–maximization algorithm. We applied it on a real-world automatic CoP displacement excursion segmentation problem and assessed its performance by performing comparisons with alternative approaches, including well-known supervised static classifiers and the standard HMM. The results obtained are very encouraging and show that the proposed approach is quite competitive, though it works in an entirely unsupervised fashion and does not requires a feature extraction preprocessing step. The present findings could help clinicians to better understand the motor strategies used by the patients during their orthostatic postures and may guide the rehabilitation process.

Force Plate Assessment of Quiet Standing Balance Control: Perspectives on Clinical Application within Stroke Rehabilitation

Assessment of balance control is essential to guide physical rehabilitation poststroke. However, current observational assessment tools available to physiotherapists provide limited information about underlying dyscontrol. This paper describes a force plate-based assessment of quiet standing balance control that we have implemented for individuals attending inpatient stroke rehabilitation. The assessment uses two force plates to measure location of ground reaction forces to maintain stability in quiet standing in five conditions (eyes open, eyes closed, standing symmetrically, and maximal loading on the less-affected and more-affected limbs). Measures of interest are variability of the centers of pressure under each foot and both feet combined, weight-bearing asymmetry, and correlation of center of pressure fluctuations between limbs. We present representative values for the above-mentioned measures and case examples to illustrate how the assessment can reveal patient-specific balance control problems and direct treatment. We identify limitations to our current assessment and recommendations for future research.

Incorporating research technology into the clinical assessment of balance and mobility: perspectives of physiotherapists and people with stroke.

To describe the perspectives of people with stroke and their physiotherapists on the use of biomechanics technology to assess balance and mobility. This qualitative study used semi-structured interviews with patients with stroke and a focus group with their physiotherapists. Coding of interview and focus-group data used a line-by-line inductive approach, with qualitative software to develop codes into themes. The quantitative data from the assessment were seen as beneficial to providing patients with insight into balance and mobility problems. Physiotherapists found that the assessment confirmed clinical reasoning and aided in precise evaluation of progress but expressed mixed opinions as to whether treatment choice was influenced. Patients would have liked more communication regarding the purpose of the assessment. Patients also stated that trust in their physiotherapists helped them overcome anxieties and that confidence was gained through exposure to more challenging balance assessments. Physiotherapists advocated for the use of a harness system to safely incorporate reactive balance control assessment and training into practice. Both patients and therapists saw value in the quantitative data provided by the assessment. Regardless of the technology used, patients value a strong physiotherapist-patient relationship. Ongoing collaboration between clinicians and researchers should guide the evolution of technology into clinically useful tools.

Clinical implementation of a reactive balance control assessment in a sub-acute stroke patient population using a ‘lean-and-release’ methodology

Reactive balance control, specifically performance of rapid stepping responses, is associated with falls, but not routinely assessed in clinical practice. Challenges to clinical assessment may include a lack of available methods that are safe, standardized and able to quantify the balance responses. We implemented a reactive balance control assessment, using lean-and-release methodology, in an inpatient stroke rehabilitation program. Through retrospective chart review of all admissions (n=183) over a 1-year period, we evaluated the clinical uptake and patient-specific factors associated with its use. Seventy-seven of 183 (42%) patients were administered the assessment, on average, 16.2 (SD 13.1) days post-admission. Patients who received the assessment were younger, at an earlier time post-stroke, with a shorter rehabilitation length of stay, with less lower-limb impairment, higher levels of functional balance, less motor and cognitive impairment, greater recovery of functional mobility, and were more likely to have the capacity to walk (all measures p<0.0001), compared to those who did not receive the assessment. This study demonstrates the potential for clinical uptake of the lean-and-release assessment among patients with stroke, who are progressing in their functional and mobility status over the course of their inpatient rehabilitation. However, the results suggest limitations in application to patients with greater disability or who demonstrate slower recovery of functional mobility. Ongoing research is required to develop clinical approaches to reactive balance control assessment that are effective, efficient and relevant to clinical populations and feasible for clinical practice.

A community-based Falls Management Exercise Programme (FaME) improves balance, walking speed and reduced fear of falling

Although effective community falls prevention programmes for the older persons have been described, challenges remain in translating proven interventions into daily practice. To evaluate the efficacy, feasibility and acceptability of a falls prevention programme that can be integrated into daily activities in a group of community-dwelling older adults with risk of falling. A cohort study with intervention and comparison groups was designed to evaluate a 36-week group-based falls prevention exercise programme (FaME) in the community setting. Participants were aged 60 years or older, had fallen in the past 12 months, had fear of falling with avoidance of activities or had deficits in balance control. Primary outcome measures included assessment of balance control and mobility; secondary outcome measures included level of physical activity, assessment of fear of falling and health-related quality of life. There were 48 and 51 participants in the intervention and comparison groups, respectively. There were improvements in measurements of balance, walking speed and self-efficacy. The drop out rate was low (14.6% and 3.9% from the intervention and comparison groups, respectively). Overall compliance in the intervention group was 79%. Factors that motivated continued participation include the regular and long-term nature of the programme helping to reinforce their exercise habits, the simplicity of movements and friendliness of the group. The FaME programme improves balance, walking speed and reduces fear of falling. It could be widely promoted and integrated into regular health and social activities in community settings.

Computerized dynamic posturography analysis of balance in individuals with a shoulder stabilization sling.

Sling immobilization of the upper limb may affect balance. Computerized dynamic posturography (CDP) provides a validated, objective assessment of balance control and postural stability under dynamic test conditions. We tested the balance of individuals with a shoulder stabilization sling (SSS) using an EquiTest machine to objectively assess imbalance while wearing a sling. Forty-two right hand dominant (RHD) adults (16 females, 26 males; average age 22 years; range 20-35years) were included in the study, comprising six controls and two SSS groups with 18 dominant hands (DH) and 18 non dominant hands (NDH). CDP assessed balance by the Sensory Organization Test (SOT), Motor Control Test (MCT), and Adaptation Test (ADT). The composite equilibrium scores (CES) were as follows: controls 80.8%, sling DH 71.1 versus sling NDH 69.6%. Sling use has lower CES compared to controls (p=0.025). The use of a sling caused 31% of subjects to have decreased CES. 22.9% of sling users had imbalances. Among sling users, the DH group had 19.1% imbalances compared to 26.8% for the NDH group (p=0.044). There were six absolute falls in the DH group versus 12 in the NDH group. Wearing a sling causes balance decompensation in almost one-third of healthy volunteers, and this is greater when worn in the non dominant hand, with double the number of falls. This has significant implications for patients having prolonged use of a sling. Consideration should be given to operative procedures or conservative management of shoulder pathology where sling use is required and promotion of the early discontinuation of sling use can be considered.

Stocktaking on the development of posturography for clinical use

This report identifies fundamental problems to be addressed in order to build relevant clinical tests of human balance while standing. The stated purpose of these tests is identification of lesion site and/or definition of functional balance deficits in a specific patient. During a recent consensus meeting (ESCEBD), 60 researchers and experienced clinical users of posturography (14 European countries, 9 different disciplines) inventoried and critically analyzed the various methodologies of posturography currently used for clinical evaluation. To complement posturography, alternative methods of assessment of balance control were considered. The indications for the clinical use of posturography were defined as well as recommendations regarding measurement parameters, type of perturbations and signal analysis techniques to improve assessment of balance control. Consensus was reached that a force platform cannot be considered as a technique which is sufficient on its own to perform a clinically relevant test for the assessment of neuro-otological and musculo-skeletal conditions, evaluation of compensation or treatment (rehabilitation) or prediction of falls. It should be supported by complementary methods, such as segment motion analysis, body-fixed 2D or 3D accelerometer-gyroscope or electromyography. At present, no generally applicable posturography test is available with reasonable sensitivity and specificity for the diagnosis of balance disorders. Perturbation techniques are most likely needed to enhance the diagnostic yield of posturography.

Postural stability in the elderly: Fallers versus non-fallers

Objectives (1) To compare static and dynamic balance alterations in recurrent fallers and non-fallers elderly patients. (2) To assess the functional repercussions of balance disorders and falls in these subjects. Patients and methods Retrospective, observational, case-control study. The patients examined were 226 community-dwelling elderly people aged over 65 years, 113 of whom had suffered more than two falls in the past 6 months, and a further 113 who had not fallen in the past 6 months. All subjects had received primary care (at one of Madrid's Area 7 Healthcare Centres) and/or had been outpatients of the Geriatrics Unit and were subjected to an exhaustive examination including the collection of demographic data, geriatric assessment, physical examination, tests of gait and balance and balance control assessment using the Balance Master ®. This last assessment included the tests: (1) modified clinical test for sensory interaction on balance (mCTSIB), which estimates sensory balance by measuring the centre of gravity (COG) sway velocity and alignment relative to the centre of the patient's base of support with open then closed eyes, and on a firm then unstable surface; (2) weight-bearing squat (WBS); (3) rhythmic weight shift; (4) sit to stand (SS); (5) walk across (WA); and (6) step up/over (SUO). Statistical analysis was performed using SPSS v.12.0 software. Results Recurrent fallers showed greater postural instability when visual and proprioceptive conditions changed than non-fallers, especially when both sensory inputs were simultaneously abolished. The speed of displacement of the centre of gravity on a foam surface was increased in the fallers both with open ( p < 0.001) or closed eyes ( p = 0.001). In the SS test, fallers took longer to stand from sitting without help ( p < 0.001). The WA test results indicated a higher gait speed for the non-fallers ( p = 0.001). Conclusions Assessing postural control systems and identifying neurological fall risk factors in patients who undergo recurrent falls is the key to adopting appropriate measures to prevent subsequent falls and thus minimize their physical, psychological and social consequences.

F16 Postural assessment in dynamic posturography—a useful motor phenotype measure for presymptomatic and manifest Huntington's disease?

BackgroundObjective assessment of balance control in dynamic posturography (DP) may be helpful to assess motor phenotype in premanifest (pHD) and symptomatic (sHD) Huntington's disease (HD). HD patients are known to...

Fast Computational Analysis of Sway Area Using Center of Pressure Data in Normal Children and Children with Cerebral Palsy

In this paper, we have developed an efficient method for real time computation of Center of Pressure (CoP) sway area using a fast search and sort based on a numerical approximation of the Green-Gauss method. In addition, we investigated the correlations among the velocity, acceleration, path length, sway area, and mean frequency of CoP signals during quiet standing in healthy children and in children with cerebral palsy. The Pearson correlation technique described the direction and strength of linear relationships among the CoP velocity, acceleration, and the standard metrics, such as CoP Root Mean Squared (RMS), CoP range, path length (PL), normalized path length (NPL), sway area (SA), normalized sway area (NSA), and mean frequency, respectively. Subjects were tested during eyes open and eyes closed trials to explore the significance of the visual input. Both RMS of CoP velocity and acceleration described strong correlations with NPL and NSA in the eye open test (r ≥ 0.728) and in the eye closed test (r ≥ 0.919) of normal children. Similar results were also observed in children with cerebral palsy in both eye tests. The correlation between the CoP velocity and NPL indicated that the CoP velocity metric can be considered as an indicator of NPL. Thus, the CoP velocity and CoP acceleration might be very useful as valid metrics because the real time feedback from online measurements in balance control assessment is often necessary. The described fast computation of the sway area by using CoP velocity and CoP acceleration provided valid metrics for CoP correlation analysis.