Acute Knee Crutch Use Provokes Changes to Postural Strategy.

Single-leg knee crutches are a relatively new, hands-free mobility assistive device with benefits over standard axillary crutches. Our main goal in this study was to evaluate balance ability in a healthy population upon first exposure to the knee crutch device. We had 20 healthy individuals (M age = 21.1; SD = 1.5 years) complete baseline static and dynamic balance tests on a force plate, followed by knee crutch fitting, a self-selected duration of ambulation practice, and another round of balance testing while wearing the knee crutch. We used the BTrackS Balance Test (BBT) to measure static balance, and the BTrackS Limits of Stability (BLOS) test to measure dynamic balance, and we created a custom lateral bias score from the BLOS results. On average, participants self-selected 3.1 minutes of ambulation practice. Wearing the knee crutch caused a near doubling of static balance path length and a large reduction in percentile ranking on the BBT. Dynamic balance area was more than halved (p < .001), with lateral bias scores during the BLOS, indicating that participants heavily favored their non-crutched leg (p < .001). Our results indicate that static and dynamic balance were significantly altered when wearing the knee crutch, and participants seemed to switch to a single leg stance strategy. Despite these balance changes, participants were quickly ready and willing to complete independent ambulation and balance testing procedures using the single-leg knee crutch.

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

BACKGROUND: Assessing postural control is important for the assessment of motor function after concussion. Data used for postural control assessment typically do not take the sport played, age, or sex of the athlete into consideration. It is plausible these variables may be significant when making return-to-play decisions. RESEARCH QUESTION: This study used the BTrackS database to examine differences in postural control in athletes playing different types of sports and across sex and age. METHODS: BTrackS data from 9093 high school to college-aged athletes (aged 14-22 years) were examined employing a One-way ANOVA with a post-hoc test to compare CoP path length between sport types. A moderation analysis was used to test interaction effects of sex and age on a CoP/BMI ratio. RESULTS: Significant differences were observed between sport types, F(3,9089) = 42.4, p <.001, η2 = 0.014. Post hoc tests indicated that collision (M = 25.0, SD = 7.6) sport athletes exhibited significantly higher CoP measures compared to the contact (M = 23.4, SD = 7.4), limited contact (M = 22.9, SD = 6.9), and non-contact (M = 23.0, SD = 7.4) athletes. There was no difference between other sport types (p >.20). A significant mean sex difference (Mmale = 0.924, Mfemale = 0.898, p <.001) and a quadratic association with age, (ß = -0.042, p <.001) was observed. Further, magnitude of those age differences decreased with age (ß = 0.011, p <.001). An interaction of age and sex was significant for linear (ß = 0.020, p <.001) and quadratic terms (ß = -0.006, p <.001). SIGNIFICANCE: Athletes exhibited different postural control when the type of sport, age, and sex was taken into consideration. This data possess clinical significance as this suggests that normative postural control data for collision sport athletes should be derived from data based upon type of sport played, age, and sex of the athlete.

An initial set of reference values for the Balance Tracking System (BTrackS) Limits of Stability protocol.

BACKGROUND: The Balance Tracking System (BTrackS) Limits of Stability (LOS) protocol is a relatively new means of evaluating unconstrained dynamic postural control ability. While the reliability of this protocol has previously been established, reference data is currently unavailable to assist in the interpretation of results. RESEARCH QUESTION: What are typical reference values for the BTrackS LOS protocol with respect to sex, height, and BMI? METHODS: A cross= -section of 800 healthy, young adults (aged 18-29 years; 368 men, 432 women) were administered the BTrackS LOS protocol. Sex, height and weight variables were also captured for the participants. RESULTS: Results of a stepwise linear regression showed that the outcome measure for BTrackS LOS testing (i.e. LOS Area) was larger in taller individuals and in men. Based on these findings, four percentile ranking categories were established and associated look-up tables created. SIGNIFICANCE: The reference values provided by this study offer much needed guidance to clinicians and researchers for the determination of dynamic balance abnormalities based on BTrackS LOS testing.

Verbal Encouragement Provokes Significant Increases in Maximal Volitional Dynamic Postural Sway.

Limits of Stability protocols are typically target-oriented, leaving volitional aspects of control unobservable. A novel unconstrained protocol, volitional Limits of Stability (vLOS), shows high test-retest-reliability. We tested if verbal encouragement impacts this protocol. Forty healthy young adults (age 20.1 ± .9 years) performed three trials of vLoS with instructions that were agnostic to strategy or vigor, except trial three included verbal encouragement. Total sway area was used to metric the maximum volitional dynamic sway during each 1-min trial. One-way, repeated-measures ANOVA revealed significant differences (F(2,117) = 41.56, p < 0.0001, ηp2 = 0.52) due to encouragement. Specifically, follow-up paired t-tests showed no difference in sway area between the first two trials (p = 0.61), while trial three was much larger than trials one and two (p < 0.0001). Significant, large increases in sway area with verbal encouragement indicate that top-down mechanisms should be considered in theories of postural control. As well, clinical utilization of novel vLOS should be careful with word selection and delivery of protocol instructions.HIGHLIGHTSLimits of Stability balance tests typically include a goal directed instruction and metrics.Dynamic postural sway should be tested in a task affording participant volitional control.A novel volitional Limits of Stability protocol has been developed.Maximal dynamic postural sway responds to motivating instructions.Psychological factors of postural sway control deserve further investigation.

Proprioceptive Acuity Influences Speech Motor Control in Healthy Adult Talkers.

PURPOSE: Somatosensory feedback, including proprioception, is important for speech production. This study evaluates proprioceptive acuity of the tongue using a position-matching task and determining if proprioceptive acuity impacts speech motor control in healthy adult talkers. METHOD: Twenty-five young adults with no history of speech, language, or hearing disorders had their tongue movements recorded with an electromagnetic articulograph while completing a position-matching task. Participants were also asked to repeat two sentences that differed in the somatosensory feedback obtained. One sentence provided both tactile and proprioceptive feedback, whereas the other primarily provided proprioceptive feedback. RESULTS: Participants ranged in proprioceptive acuity as measured by the position-matching task. Talkers with smaller position-matching errors and, therefore, higher proprioceptive acuity had smaller movements and slower speeds for both sentences. Talkers with lower proprioceptive acuity had reduced speech movement stability for the sentence that primarily provides proprioceptive feedback. CONCLUSION: Proprioceptive acuity of the tongue can be evaluated using a position-matching task, and acuity is associated with more efficient speech movements and greater speech movement stability, particularly when producing utterances that provide less tactile feedback. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.24293740.

Potential Factors Associated with Healthcare Utilization for Balance Problems in Community-Dwelling Adults within the United States: A Narrative Review.

Falls are the leading cause of mortality and chronic disability in elderly adults. There are effective fall prevention interventions available. But only a fraction of the individuals with balance/dizziness problems are seeking timely help from the healthcare system. Current literature confirms the underutilization of healthcare services for the management of balance problems in adults, especially older adults. This review article explores factors associated with healthcare utilization as guided by the Andersen Healthcare Utilization Model, a framework frequently used to explore the factors leading to the use of health services. Age, sex, race/ethnicity, BMI, and comorbidities have been identified as some of the potential predisposing factors; socioeconomic status, health insurance, and access to primary care are the enabling and disabling factors; and severity of balance problem, perceived illness, and its impact on daily activities are the factors affecting need for care associated with healthcare utilization for balance or dizziness problems. Knowledge about these barriers can help direct efforts towards improved screening of vulnerable individuals, better access to care, and education regarding effective fall prevention interventions for those who are at risk for underutilization. This can aid in timely identification and management of balance problems, thereby reducing the incidence of falls.

Six Weeks of at Home BTrackS Target Tracking Training Induces Sustained Dynamic Balance Improvement in Healthy Young Adults.

Purpose: The Balance Tracking System's Target Tracking Training protocol requires an individual to keep an onscreen dot within a moving target circle via leaning movements that are sensed by a Balance Tracking System's balance plate. The present study sought to determine for the first time if short duration at-home training using Balance Tracking System's Target Tracking Training could improve dynamic balance. Methods: Fifteen healthy young adults (mean age = 22.4 years) performed Balance Tracking System's Target Tracking Training for six weeks at home, with an average of five, three-minute sessions per week. The first three weeks of Balance Tracking System's Target Tracking Training were completed on the firm surface of a Balance Tracking Systems Balance Plate, while the final three weeks were performed on a foam cushion on top of the plate. This was followed by a three-week retention period where participants performed no training. Dynamic balance changes were assessed at multiple timepoints with the Balance Tracking System's Limits of Stability protocol. Results: Participants significantly improved Balance Tracking System's Target Tracking Training from the first to last day of training in both three-week periods (p<0.01). This increase was mirrored by improved Balance Tracking System's Limits of Stability results. Specifically, Balance Tracking System's Limits of Stability area (ie dynamic balance) increased significantly from Baseline to the end of the first three weeks of training (p<0.001), and again after the second three weeks (p<0.01). These gains were maintained following the retention period. Conclusion: The present findings support use of short duration Balance Tracking System's Target Tracking Training to improve dynamic balance at home. This increase in dynamic balance could ultimately be used a practical means of improving athletic performance.

Lower Limb Asymmetry Evaluation Using the Balance Tracking System (BTrackS) Single Leg Stance Protocol.

Single Leg Stance (SLS) balance testing is a common means of determining lower limb asymmetries in motor behavior. The Balance Tracking System (BTrackS) Balance Plate is a low-cost, portable force plate for objectively obtaining balance measurements. The present study provides the first known balance results for the BTrackS SLS protocol. BTrackS SLS testing was conducted on 161 young adults (90 women, 71 men) according to the test's standardized instructions. Specifically, participants performed one-legged (left or right) stance on the BTrackS Balance Plate for four, (2 practice, 2 actual) 20 s trials. SLS test outputs included total Center of Pressure path length and absolute symmetry index. Results showed that women had better SLS performance than men and that both sexes performed better on the actual compared to practice trial. Systematic one-sample t-tests of the Absolute Symmetry Index measures showed that a difference of 16% or greater between legs represented asymmetric performance. These results have clear value for individuals using BTrackS SLS testing to evaluate potential asymmetries. Additionally, these findings agree with previous reports showing sex differences favoring women on tests of static balance, and validate the use of a practice trial in the BTrackS SLS protocol.

Differences in body sway can be identified in Huntington's disease using a practical balance assessment device.

INTRODUCTION: Huntington's disease (HD) is a progressive neurodegenerative disorder with motor, cognitive, and psychiatric symptoms that typically manifest in middle adulthood. Balance assessments may be useful for predicting disease onset and progression, but studies are limited. We aimed to enhance estimates of HD onset using an inexpensive and practical body sway assessment device [i.e., Wii Balance Board (WBB)]. METHODS: We assessed total body sway (TBS) on 64 HD gene carriers [Presymptomatic HD (PsHD; n = 16); Prodromal HD (ProHD; n = 16); HD (n = 32)] and 21 demographically similar normal controls (NC) employing a WBB and custom-designed laptop software. Participants completed balance test trials that included combinations of eyes open or closed while standing on a stable versus unstable surface. Non-parametric analyses were conducted to assess group differences in TBS conditions. RESULTS: The HD group had significantly higher TBS in most balance conditions relative to NC, PsHD, and ProHD groups (ps < .05). Importantly, the ProHD group demonstrated higher TBS relative to NC in all balance conditions (ps < .05) with medium to large effect size ranges (r≥ 0.40). No differences in TBS were exhibited between NC and PsHD groups (ps > .05). CONCLUSIONS: Increased body sway, easily evaluated using a brief, objective balance assessment, may serve as an important functional marker in patients with, and during the transition to, HD. Further studies are needed to confirm and extend these findings.

Impact of Sub-Clinical and Clinical Compression Socks on Postural Stability Tasks among Individuals with Ankle Instability.

Compression socks are used by a very diverse group of individuals and may potentially have a greater impact on physically diminished or impaired individuals as opposed to healthy individuals. The purpose of this study was to compare the effects of sub-clinical (SC) and clinical (CL) compression socks among healthy (CON), copers (COP), and individuals with chronic ankle instability (CAI). Postural stability was evaluated in 20 participants (11 males and 9 females) using Balance Tracking System Balance platform (BTrackS™) during the modified clinical test of sensory integration in balance (mCTSIB) and limits of stability (LOS) tests. Postural sway parameters were analyzed using a mixed model repeated measures analysis of variance 3 (group: CON, COP, and CAI) by 3 (compression condition: BF, SC, and CL) × 4 (balance condition: EO, EC, EOF, and ECF) for mCTSIB and a 3 (group: CON, COP, and CAI) by 3 (compression condition: BF, SC, CL) × 4 (balance condition: FL, BL, BR, FR) for LOS. Results revealed significantly greater postural stability with both SC and CL compression socks when compared to barefoot conditions. However, no significant differences were observed among groups for compression socks grades. Both SC and CL compression socks may be effective in increasing postural stability.

Balance Differences between North and South American Older Adults: A Cross-Sectional, Age and Sex Matched Study.

This study aimed to characterize the risk of falling in low-, moderate- and high-risk participants from two different geographical locations using a portable force-plate. A sample of 390 older adults from South and North America were matched for age, sex, height and weight. All participants performed a standardized balance assessment using a force plate. Participants were classified in low, moderate and high risk of falling. No differences were observed between South and North American men, nor comparing North American men and women. South American women showed the significantly shorter center of pressure path length compared to other groups. The majority of the sample was categorized as having low risk of falling (male: 65.69% and female: 61.87%), with no differences between men and women. Moreover, no differences were found between North vs. South Americans, nor between male and female groups compared separately. In conclusion, South American women had better balance compatible with the status of the 50-59 years' normative age-range. The prevalence of low falls risk was~61-65%; the prevalence of moderate to high risk was~16-19%. The frequency of fall risk did not differ significantly between North and South Americans, nor between males and females.

Test-Retest Reliability of the Balance Tracking System Modified Clinical Test of Sensory Integration and Balance Protocol Across Multiple Time Durations.

BACKGROUND: Postural control is critical for body sway control and is subserved by three sources of sensory feedback (ie, vision, proprioception and vestibulation). A method for determining the relative contribution of each sensory feedback source to postural control is the modified clinical test of sensory integration and balance for the balance tracking system (BTrackS). However, this method has not yet been evaluated for test-retest reliability. PURPOSE: To determine the test-retest reliability of the modified clinical test of sensory integration and balance protocol for the BTrackS across multiple time intervals. METHODS: Three groups of healthy young adults performed the BTrackS modified clinical test of sensory integration and balance protocol four times separated by either one day, one week or one month. Within each time duration group, and condition, differences in total center of pressure path length were determined from one test session to the next and intra class correlation coefficient categorizations were made. RESULTS: In all but one case, no significant difference in performance was seen from one testing session to the next. The one significant difference found was a decrease in total center of pressure path length from day 1 to day 2 in the vestibular condition of the group tested daily. Intra class correlation coefficient results largely indicated fair-good reliability across time durations and test conditions. CONCLUSION: The present study largely supports use of the BTrackS modified clinical test of sensory integration and balance protocol as a means of probing the sensory contributions to balance performance across multiple time durations.

BTrackS limits of stability test is a reliable assessment of volitional dynamic postural control.

BACKGROUND: Unconstrained limits of stability assessment reveals aspects of volitional postural sway control that are inaccessible by other means. Prior versions of this assessment include instructions to sway towards predefined targets, and may not capture the full capability of the individual. RESEARCH QUESTION: This study sought to establish the test-retest reliability of a novel limits of stability protocol. METHODS: Volitional sway area was determined during unconstrained trials, where participants were instructed to explore their ability to sway towards the perimeter of their base of support. Visual feedback was provided via computer monitor. Forty healthy young adults (mean age = 20.2 ± 1.3, 15 males, 25 females) participated in this study. Trials were collected in three sessions, repeated at the same time of the same day, with one week between. Reliability was assessed using IntraClass Correlation Coefficients (ICC), considering the total area of sway as well as quadrant level area. RESULTS: Reliability was moderate between the first and second session (0.583), and much higher 0.921) between the second and third session. The quadrant level reliability was poor to excellent (0.183-0.791), with similar trends between the three sessions. SIGNIFICANCE: Ultimately, these results indicate that the novel limits of stability test is reliable. However, it is recommended that a practice trial be conducted prior to baseline establishment.

Effects of a Community-Based Exercise Program on Older Adults' Physical Function, Activities of Daily Living, and Exercise Self-Efficacy: Feeling Fit Club.

Community-based exercise programs have demonstrated feasibility, yet many lack controlled studies examining their efficacy. This study examined the efficacy of a community-based exercise program, using a controlled design. Participants (N = 262, Mage = 74.0 years, SD = 8.4) were women (77%) and men recruited from senior centers served by the county Area Agency on Aging. Intervention participants (n = 133) were newly enrolled in classes. Controls (n = 129) were recruited from matched sites not offering classes. Validated measures of physical function, exercise self-efficacy, balance, and activities of daily living (ADL) confidence were administered at baseline and 3 months. Significant improvements in upper and lower body strength, aerobic endurance, mobility, exercise self-efficacy, and balance were found in the exercisers but not controls. No changes in ADL confidence occurred in exercisers, while significant decreases occurred in controls. Findings support the efficacy of the county-wide program. Building an evidence base for community-delivered programs should provide impetus for increased dissemination through state and national agencies thereby increasing program impact.

Safety, tolerability, pharmacokinetics, and pharmacodynamics of low dose lysergic acid diethylamide (LSD) in healthy older volunteers.

Research has shown that psychedelics, such as lysergic acid diethylamide (LSD), have profound anti-inflammatory properties mediated by 5-HT2A receptor signaling, supporting their evaluation as a therapeutic for neuroinflammation associated with neurodegenerative disease. OBJECTIVE: This study evaluated the safety, tolerability, pharmacokinetics, and pharmacodynamics of orally repeated administration of 5 µg, 10 µg, and 20 µg LSD in older healthy individuals. In the current paper, we present safety, tolerability, pharmacokinetics, and pharmacodynamic measures that relate to safety, tolerability, and dose response. METHODS: This was a phase 1 double-blind, placebo-controlled, randomized study. Volunteers were randomly assigned to 1 of 4 dose groups (5 µg, 10 µg, 20 µg LSD, and placebo), and received their assigned dose on six occasions (i.e., every 4 days). RESULTS: Forty-eight older healthy volunteers (mean age = 62.9 years) received placebo (n = 12), 5 µg (n = 12), 10 µg (n = 12), or 20 µg (n = 12) LSD. LSD plasma levels were undetectable for the 5 µg group and peak blood plasma levels for the 10 µg and 20 µg groups occurred at 30 min. LSD was well tolerated, and the frequency of adverse events was no higher than for placebo. Assessments of cognition, balance, and proprioception revealed no impairment. CONCLUSIONS: Our results suggest safety and tolerability of orally administered 5 µg, 10 µg, and 20 µg LSD every fourth day over a 21-day period and support further clinical development of LSD for the treatment and prevention of Alzheimer's disease (AD).

Normative data for the Balance Tracking System modified Clinical Test of Sensory Integration and Balance protocol.

Purpose: Force plate balance testing technology has traditionally been underutilized in clinical and research settings due to the high cost and lack of portability. A relatively new force plate called the Balance Tracking System (BTrackS) has been developed to overcome these barriers. BTrackS recently implemented the modified Clinical Test of Sensory Integration and Balance (mCTSIB) as a means of evaluating various sources of sensory information for postural sway control. The present study aimed to provide much needed normative data for the BTrackS mCTSIB protocol. Materials and methods: Data from 604 healthy adults (308 women; 296 men) between the ages of 18 and 29 years were collected according to the BTrackS mCTSIB protocol. The protocol consisted of four, 20-second static standing trials that manipulated relative contributions of the vision, proprioception and vestibular sensory systems through various eyes open/closed and foam/no foam conditions. Comparisons of men versus women and the impact of body size (ie body mass index) were determined so that relevant percentile rankings could be calculated. Results: Analysis of variance showed an interaction between sex and task condition on the BTrackS mCTSIB (p<0.001). This interaction indicated that women outperformed men on all conditions, but especially in the fourth trial where eyes were closed and standing was done on a compliant foam surface. Percentile rankings were calculated based on sex and BTrackS mCTSIB condition. No relationship was found between BTrackS mCTSIB results and body size. Conclusion: Normative data provided in this study are vital for establishing potential sensory feedback-based balance dysfunctions that may exist clinically or in laboratory settings. In addition, this data can aid in the tracking of changes over a rehabilitation period and/or the effectiveness of balance interventions.

Normative Data for the BTrackS Balance Test Concussion-Management Tool: Results From 10 045 Athletes Aged 8 to 21 Years.

CONTEXT: Balance tests are a recommended assessment of motor function in concussion protocols. The BTrackS Balance Test (BBT) is a tool for concussion balance testing that uses low-cost force-plate technology to objectively measure postural sway. OBJECTIVE: To provide normative data for the BBT in a large population of athletes. DESIGN: Cross-sectional study. SETTING: Concussion baseline testing at multiple facilities. PATIENTS OR OTHER PARTICIPANTS: Male and female athletes (n = 10 045) ages 8 to 21 years. INTERVENTION(S): Athletes performed three 20-second trials of eyes-closed standing on the BTrackS Balance Plate with feet shoulder-width apart and hands on hips. MAIN OUTCOME MEASURE(S): Postural sway was measured as the average total center-of-pressure path length over 3 testing trials. RESULTS: Postural sway was reduced (ie, balance improved) as athlete age increased and was less in female athletes than in male athletes. Percentile ranking tables were calculated based on sex and 2-year age groupings. CONCLUSIONS: Our findings (1) provide context for BBT results performed in the absence of a baseline test, (2) can help mitigate athlete malingering, and (3) might identify individuals with latent neuromuscular injuries during baseline tests.

Postural sway normative data across the adult lifespan: Results from 6280 individuals on the Balance Tracking System balance test.

AIM: Postural sway measured using force plate technology is a known risk factor for falls in older adults, but is currently underutilized due to the high cost and lack of portability issues associated with most force plate systems. The Balance Tracking System (BTrackS) is a new force plate that alleviates these barriers and has potential for widespread use. The present study provides important normative data for the BTrackS Balance Test of postural sway that improves its translational value to the field of gerontology. METHODS: BTrackS Balance Test postural sway results were accumulated from 6280 community-dwelling individuals across the adult lifespan. Data were assessed for effects of age, sex and body size. Stratified percentile rankings were then calculated. RESULTS: BTrackS Balance Test results were dependent on age and sex, but not body size. Percentile rankings were, therefore, determined across various age groups for men and women separately, with no consideration of participant body size. A novel interaction was found between the age and sex factors, suggesting enhanced postural sway ability for women that becomes more pronounced with older age. CONCLUSIONS: The results of the present study represent one of the largest sets of normative postural sway data ever published. These data translate directly into the field of gerontology as a tool for determining abnormalities in postural sway, which have been linked to various poor outcomes in older adults, such as high fall risk. Geriatr Gerontol Int 2018; 18: 1225-1229.