Control of balance is complex and involves maintaining postures, facilitating movement, and recovering equilib- rium. Balance control consists of controlling the body center of mass over its limits of stability. Clinical balance assessment can help to assess fall risk and/or determine the underlying reasons for balance disorders. Most func- tional balance assessment scales assess fall risk and the need for balance rehabilitation but do not differentiate types of balance deficits. A system approach to clinical bal- ance assessment can differentiate different kinds of bal- ance disorders and a physiological approach can deter- mine underlying sensorimotor mechanisms contribut- ing to balance disorders. Objective measures of balance using computerized systems and wearable inertial sensors can bring more sensitive, specific and responsive bal- ance testing to clinical practice.

http://disciplinas.stoa.usp.br/mod/resource/view.php?id=132603

The relevance of clinical balance assessment tools to differentiate balance deficits

Foundations of Clinical Research: Applications to Practice, 2nd Edition, Leslie Gross Portney, Mary P. Watkins. Prentice Hall, Upper Saddle River, NJ (2000), 752 pages. $60

Options for people with severe paralysis who have lost the ability to communicate orally are limited. We describe a method for communication in a patient with late-stage amyotrophic lateral sclerosis (ALS), involving a fully implanted brain–computer interface that consists of subdural electrodes placed over the motor cortex and a transmitter placed subcutaneously in the left side of the thorax. By attempting to move the hand on the side opposite the implanted electrodes, the patient accurately and independently controlled a computer typing program 28 weeks after electrode placement, at the equivalent of two letters per minute. The brain–computer interface offered autonomous communication that supplemented and at times supplanted the patient’s eye-tracking device. (Funded by the Government of the Netherlands and the European Union; ClinicalTrials.gov number, NCT02224469.)

Fully Implanted Brain-Computer Interface in a Locked-In Patient with ALS.

The different techniques and methods employed as well as the different quantitative and qualitative variables measured in order to objectify postural control are often chosen without taking into account the population studied, the objective of the postural test, and the environmental conditions. For these reasons, the aim of this review was to present and justify the different testing techniques and methods with their different quantitative and qualitative variables to make it possible to precisely evaluate each sensory, central, and motor component of the postural function according to the experiment protocol under consideration. The main practical and technological methods and techniques used in evaluating postural control were explained and justified according to the experimental protocol defined. The main postural conditions (postural stance, visual condition, balance condition, and test duration) were also analyzed. Moreover, the mechanistic exploration of the postural function often requires implementing disturbing postural conditions by using motor disturbance (mechanical disturbance), sensory stimulation (sensory manipulation), and/or cognitive disturbance (cognitive task associated with maintaining postural balance) protocols. Each type of disturbance was tackled in order to facilitate understanding of subtle postural control mechanisms and the means to explore them.

/pdf/techniques-and-methods-for-testing-the-postural-function-in-2n6o22lbdv.pdf

Techniques and Methods for Testing the Postural Function in Healthy and Pathological Subjects.

Background Recently, a new tool for assessing dynamic balance impairments has been presented: the 14-item Mini-BESTest.

Objective Aim of this study was to compare the psychometric performance of Mini-BESTest vs. Berg Balance Scale (BBS).

Methods Ninety-three subjects (mean age 66.2; 53 females) with balance deficits were recruited. Interrater (3 raters) and test-retest (1-3 days) reliability were calculated using intraclass correlation coefficients (ICCs). Responsiveness and minimal important change (MIC) were assessed (after 10 sessions of physical therapy) using both distribution-based and anchor-based methods (external criterion: a 15-point Global Rating of Change [GRC] scale).

Results At baseline, neither floor nor ceiling effects were found in either scale. After treatment, the maximum score was found in 12 patients (12.9%) with BBS and in 2 (2.1%) with Mini-BESTest. Test-retest reliability for total scores was significantly higher in Mini-BESTest (ICC=0.96) than in BBS (ICC=0.92), whereas interrater reliability was similar (ICC=0.98 vs. 0.97). The standard error of measurement (SEM) was 1.26 and minimum detectable change at the 95% confidence level (MDC95) 3.5 points for Mini-BESTest, whereas SEM was 2.18 and MDC95 6.2 points for BBS. In receiver operating characteristic (ROC) curves, the area under the curve was 0.92 for Mini-BESTest and 0.91 for BBS. The best Minimal Important Change (MIC) was 4 points for Mini-BESTest and 7 for BBS. After treatment, 38 patients at Mini-BESTest vs. only 23 at BBS (out of the 40 subjects who had a GRC ≥3.5) showed a score change equal or greater than MICs.

Conclusions The two scales behave similarly, but the Mini-BESTest scale seems to have a lesser ceiling effect, slightly higher reliability levels, and greater accuracy in classifying individual patients who show significant improvement in balance function.

/pdf/comparison-of-reliability-validity-and-responsiveness-of-the-2931gi3w3l.pdf

Comparison of Reliability, Validity, and Responsiveness of the Mini-BESTest and Berg Balance Scale in Patients With Balance Disorders

Objective: To improve, with the aid of psychometric analysis, the Balance Evaluation Systems Test (BESTest), a tool designed to analyse several postural control systems that may contribute to poor functional balance in adults. Methods: Performance of the BESTest was examined in a convenience sample of 115 consecutive adult patients with diverse neurological diagnoses and disease severity, referred to rehabilitation for balance disorders. Factor (both explorative and confirmatory) and Rasch analysis were used to process the data in order to produce a new, reduced and coherent balance measurement tool. Results: Factor analysis selected 24 out of the 36 original BESTest items likely to represent the unidimensional construct of “dynamic balance”. Rasch analysis was then used to: (i) improve the rating categories, and (ii) delete 10 items (misfitting or showing local dependency). The model consisting of the remaining 14 tasks was verified with confirmatory factor analysis to meet the stringent requirements of modern measurement. Conclusion: The new 14-item scale (dubbed mini-BESTest) focuses on dynamic balance, can be conducted in 10–15 min, and contains items belonging evenly to 4 of the 6 sections from the original BESTest. Further studies are needed to confirm the usefulness of the mini-BESTest in clinical settings.

/pdf/using-psychometric-techniques-to-improve-the-balance-2jwd5s1bcl.pdf

Using psychometric techniques to improve the balance evaluation systems test: the mini-bestest

People with amyotrophic lateral sclerosis (PwALS) show progressive loss of voluntary muscle strength. In advanced disease, motor and phonatory impairments seriously hinder the patient's interpersonal communication. High-tech devices such as eye tracking communication devices (ETCDs) are used to aid communication in the later stages of ALS. We sought to evaluate the effect of ETCDs on patient disability, quality of life (QoL), and user satisfaction, in a group of 35 regular ETCD users in late-stage ALS with tetraplegia and anarthria. The following scales were administered: 1) the Individually Prioritized Problem Assessment (IPPA) scale, in three conditions: without device, with ETCD and, when applicable, with an Eye Transfer (ETRAN) board; 2) the Psychosocial Impact of Assistive Devices Scale (PIADS); and 3) the Quebec User Evaluation of Satisfaction with Assistive Technology (QUEST 2.0). With ETRAN, IPPA showed an increase in communicative abilities with respect to the condition without device, but ETCD produced a further significant increase. PIADS evidenced a large increase of QoL, and QUEST 2.0 showed high user satisfaction with ETCD use. In conclusion, ETCDs should be considered in late-stage ALS with tetraplegia and anarthria, since in these patients they can reduce communication disability and improve QoL.

Eye tracking communication devices in amyotrophic lateral sclerosis: impact on disability and quality of life.

Stabilometry is a predictor of gait performance in chronic hemiparetic stroke patients.

https://www.archives-pmr.org/article/S0003-9993(10)00774-4/pdf

Marco Godi

Papers

Using psychometric techniques to improve the balance evaluation systems test: the mini-bestest

Comparison of Reliability, Validity, and Responsiveness of the Mini-BESTest and Berg Balance Scale in Patients With Balance Disorders

Eye tracking communication devices in amyotrophic lateral sclerosis: impact on disability and quality of life.

Stabilometry is a predictor of gait performance in chronic hemiparetic stroke patients.

Balance rehabilitation by moving platform and exercises in patients with neuropathy or vestibular deficit.