Can Backward Walking Speed Reserve Discriminate Older Adults at High Fall Risk?

Purpose: The authors examine whether community-dwelling older adults at high fall risk have lower backward walking speed reserve (WSR) than their healthy counterparts. Method: Twenty-one healthy older adults and 20 older adults at high fall risk performed five trials of forward walking at a self-selected and maximal pace. In addition, all participants walked backward at a self-selected pace, and 15 participants from each group walked backward at a maximal pace. WSR was calculated as the difference between maximal and self-selected walking speed. Comparisons between groups were made using a one-tailed independent samples t-test or Mann-Whitney U-test with an α value of 0.025. Results: Older adults at high fall risk were significantly slower during self-selected forward walking (11.7%; p = 0.006), maximal forward walking (15.5%; p = 0.001), self-selected backward walking (25.3%; p = 0.002), and maximal backward walking (23.8%; p = 0.006). Older adults at high fall risk showed a lesser forward WSR (25.4%; p = 0.03) and backward WSR (23.7%; p = 0.03). Conclusions: Backward WSR is not useful for discriminating between healthy older adults and older adults at high fall risk. The results imply that forward or backward walking speed rather than WSR might be a useful measure.

Objectif : examiner si les adultes âgés qui vivent en communauté et qui sont très vulnérables aux chutes ont une moins bonne réserve de vitesse de marche (RVM) à reculons que leurs homologues en bonne santé. Méthodologie : au total, 21 adultes âgés en bonne santé et 20 adultes âgés très vulnérables aux chutes ont effectué cinq essais de marche vers l'avant à leur vitesse maximale. Tous les participants ont également marché à reculons à la vitesse qu'ils ont choisie et 15 participants de chaque groupe ont marché à reculons à leur vitesse maximale. La RVM correspondait à la différence entre la vitesse de marche maximale et la vitesse choisie. Les chercheurs ont comparé les groupes au moyen du test de Student unilatéral pour échantillons indépendants ou du test U de Mann-Whitney d'une valeur alpha de 0,025. Résultats : les adultes âgés très vulnérables aux chutes étaient considérablement plus lents pendant la marche vers l'avant à leur vitesse (11,7 %, p = 0,006), la marche vers l'avant à la vitesse maximale (15,5 %, p = 0,001), la marche vers l'arrière à leur vitesse (25,3 %, p = 0,002) et la marche vers l'arrière à la vitesse maximale (23,8 %, p = 0,006). Les adultes âgés très vulnérables aux chutes présentaient une RVM vers l'avant (25,4 %, p = 0,03) et à reculons (23,7 %, p = 0,03) plus faible. Conclusions : la RVM à reculons n'est pas utile pour distinguer entre les adultes âgés en santé et ceux très vulnérables aux chutes. D'après les résultats, la vitesse de marche vers l'avant ou à reculons pourrait être une mesure préférable à la RVM.

Use of Backward Walking Speed to Screen Dynamic Balance and Mobility Deficits in Older Adults Living Independently in the Community.

BACKGROUND AND PURPOSE: Older adults who live independently in the community are higher functioning and routinely ambulate in the community. Unrestricted community ambulation increases the likelihood of encountering precarious situations challenging balance. Sufficient dynamic balance is necessary to avoid falls. Currently used balance and mobility assessments may not sufficiently challenge dynamic balance to uncover mobility deficits in independent community-dwelling older adults. The purpose of this study was to investigate whether backward walking speed (BWS) can serve as an outcome measure to screen dynamic balance and mobility deficits in independent community-dwelling older adults. METHODS: A convenience sample of 30 older adults (73.68 ± 6.54 years) participated in this cross-sectional study. Participants walked backward on an instrumented walkway to record BWS. Other outcomes included forward walking speed (FWS), Community Balance and Mobility (CB&M) Scale, Falls Efficacy Scale-International (FES-I), Timed Up and Go (TUG) test, and 7-day average step count (ASC). A multivariate analysis of variance investigated the overall group differences between older adults at fall risk and those not at risk and was followed up by univariate tests. Pearson and spearman coefficients investigated associations between study outcomes. Youden's index assessed diagnostic accuracy. RESULTS AND DISCUSSION: Backward walking speed, CB&M, FES-I, ASC discriminated older adults at fall risk from those not at risk (P < .01) whereas FWS and TUG did not. Backward walking speed strongly correlated with challenging assessments of balance and mobility (CB&M, FES-I, and ASC) but only moderately correlated with the TUG. The CB&M Scale independently explained 53% variance in the BWS performance (P < .01). Youden's index was highest (Y = 0.6, sensitivity = 93%, and specificity = 67%) for BWS (0.73 m/s) compared with other study outcomes. CONCLUSIONS: Preliminary results suggest that BWS can screen for dynamic balance and mobility deficits in independent community-dwelling older adults. Accurate screening is the first step to capture early decline in function for independent community-dwelling older adults. Longitudinal follow-up studies are warranted to validate BWS as a screening tool.

Functional rehabilitation of a person with transfemoral amputation through guided motor imagery: a case study.

Background: Motor imagery (MI) is a mental technique, absent of physical movement, to foster movement patterns and relieve pain via a training model enacting the brain before the body. This case study assessed MI's efficacy in decreasing phantom limb pain and attaining functional gait and balance after lower extremity amputation. Description: The participant was a 71-year-old female with a transfemoral amputation seven years prior. She required a standard walker for ambulation. The participant underwent three sessions per week for four weeks of MI intervention, with immediate, post-test, and 1-week retention testing involving subjective and functional assessments. Intervention sessions involved quiet sitting with eyes closed while listening to the MI script. The scripts focused on functional movement patterns and tasks that were relevant to the participant, such as walking, balancing, and reaching. Each session's script focused on a different task. These scripts guided her through proper action and biomechanics of the skills to imagine herself moving safely and functionally. Outcomes: Short Form Berg Balance Scale and Tinetti Performance Oriented Mobility Assessment scores demonstrated clinically important and sustained improvement. Further, the participant reported decreased phantom limb pain and could walk a short distance independently for the first time in seven years. Discussion: MI is a time- and cost-effective, low-risk treatment option that decreased phantom pain and improved balance and functional gait in an individual with an amputation. The use of MI as an intervention for the rehabilitation of persons with amputation must be further examined.

Concurrent Validity of the Zeno Walkway for Measuring Spatiotemporal Gait Parameters in Older Adults.

BACKGROUND AND PURPOSE: Previous studies have shown that older adults at high fall risk exhibit altered spatiotemporal gait parameters such as lesser gait speed, shorter step length, and greater step width compared with their healthy counterparts. Measurement of these gait parameters for older adults can play a pivotal role in clinical evaluation. While the GAITRite walkway has been previously validated and used extensively for research purposes, the Zeno walkway validity has not been established. Although both walkways use pressure sensor-based technology, comparison of the spatiotemporal gait measurements between the systems for older adults is unknown. Our purpose was to determine the concurrent validity of the Zeno walkway with the gold-standard GAITRite walkway among healthy older adults and those at high fall risk using a cross-sectional study design. METHODS: Thirty healthy older adults and 17 older adults at high fall risk performed 5 walking trials barefoot on a 16´ × 4´ Zeno walkway and a 14´ × 2´ GAITRite walkway in a quasi-randomized order. Testing on the Zeno walkway was performed in a continuous manner while testing on the GAITRite walkway was performed using 5 discrete trials. Walking trials were done at self-selected comfortable and fast pace conditions. Data from the Zeno walkway were processed using the PKMAS software. Data from the GAITRite were processed using the GAITRite software. For each group and condition, spatiotemporal gait parameters common to both walkways' footfall processing software were compared using a Wilcoxon signed rank test. Concurrent validity was estimated using intraclass correlation coefficient (ICC(2,5)) and Bland-Altman plots. RESULTS AND DISCUSSION: Both groups had significantly greater stride width on the GAITRite walkway during both conditions. During the fast pace condition, both groups walked with greater gait speed, cadence, and stride velocity, lesser step time, stance time, and double-support time, greater percentage of gait cycle spent in single-support phase, and lesser percentage of gait cycle spent in double-support phase on the GAITRite walkway. Differences observed could be attributed to surface textures, software used to process the footfalls, dimensions of the walkways, or the continuous versus discrete protocols used in the current study. The ranges of ICC(2,5) values for healthy older adults and adults at high fall risk walking at a comfortable pace were 0.449 to 0.918 and 0.854 to 0.969 and at a fast pace were 0.784 to 0.964 and 0.850 to 0.976, respectively. These values imply that the concurrent validity was moderate for most temporal parameters when healthy older adults walked at comfortable pace and excellent otherwise. Overall, the concurrent validity between both walkways was acceptable. CONCLUSION: Concurrent validity for spatiotemporal parameters between the GAITRite walkway and the Zeno walkway was moderate to excellent for older adults dependent on the specific parameter (spatial vs temporal), population (healthy or fall risk), and walking pace (comfortable or fast).

Lower Quarter Y-Balance Test in healthy women 50-79 years old.

The Lower Quarter Y-Balance Test (LQ-YBT), a measure of dynamic balance used in young adults, has not been adequately studied in older women. We determined the reliability, normative values, and relationships to other balance measures for LQ-YBT in women aged 50-79 years. Interrater reliability was strong, and test-retest reliability was moderate to strong. Results by decade showed women 50-59 years had significantly better scores than both older groups. There were moderate positive correlations between single leg stance, gait speed, and LQ-YBT composite score. LQ-YBT may be used as a dynamic balance assessment in healthy older women.

Vibrotactile Feedback Alters Dynamics Of Static Postural Control In Persons With Parkinson's Disease But Not Older Adults At High Fall Risk.

BACKGROUND: Aging and Parkinson's disease are often associated with impaired postural control. Providing extrinsic feedback via vibrotactile sensation could supplement intrinsic feedback to maintain postural control. RESEARCH QUESTION: We investigated the postural control response to vibrotactile feedback provided at the trunk during challenging stance conditions in older adults at high fall risk and individuals with Parkinson's disease compared to healthy older adults. METHODS: Nine older adults at high fall risk, 9 persons with Parkinson's disease and 10 healthy older adults performed 30s quiet standing on a force platform under five challenging stance conditions with eyes open/closed and standing on firm/foam surface with feet together, each with and without vibrotactile feedback. During vibrotactile feedback trials, feedback was provided when participants swayed >10% over the center of their base of support. Participants were instructed vibrations would be in response to their movement. Magnitude of postural sway was estimated using center of pressure path length, velocity, and sway area. Dynamics of individuals' postural control was evaluated using detrended fluctuation analysis. RESULTS: Results showed that vibrotactile feedback induced a change in postural control dynamics among persons with Parkinson's disease when standing with intact intrinsic visual input and altered intrinsic somatosensory input, but there was no change in sway magnitude. However, use of vibrotactile feedback did not significantly alter dynamics of postural control in older adults with high risk of falling or reduce the magnitude of sway. SIGNIFICANCE: Considering the effects of vibrotactile feedback were dependent on the population and stance condition, designing an optimal therapeutic regimen for balance training should be carefully considered and be specific to a target population. Furthermore, our results suggest that explicit instructions on how to respond to the vibrotactile feedback could affect training outcome.

The effects of exergaming and treadmill training on gait, balance, and cognition in a person with Parkinson's disease: A case study.

BACKGROUND: Parkinson's disease (PD) commonly impairs posture, gait, and cognition. Exercise in the form of aerobic activity as well as exergaming may improve motor ability and cognition in persons with PD. Exergaming and treadmill training can be a practical form of exercise within the home; however, there is minimal research on this combined multimodal intervention for persons with PD. OBJECTIVE: We investigated the effects of this combined intervention on cognition, balance, and gait in a person with PD through supervised lab sessions augmented by home-based sessions. METHODS: This case study utilized an ABA single subject experimental design with 4 weeks of pre-intervention, followed by 8 weeks of intervention, and 4 weeks of post-intervention. The intervention consisted of treadmill walking and Xbox Kinect exergaming, 30 minutes each, performed unsupervised at home and at supervised lab sessions. The two standard deviation band method was used to determine significance. RESULTS: MiniBEST test, 2-minute walk distance, sway area, endurance test, and a few parameters of gait initiation and gait improved significantly throughout the intervention period. Only a few measures sustained the improvement 4 weeks after completion of intervention. CONCLUSION: Eight weeks of treadmill and exergaming intervention with a person with PD improved static and dynamic postural control measures, but not gait, cognition, endurance, and clinical measures of balance. Longer and more intense multimodal intervention may be warranted.

Relationships between trunk performance, gait and postural control in persons with multiple sclerosis.

BACKGROUND: Multiple sclerosis (MS) is a chronic progressive disease of the central nervous system. Compared to healthy individuals, persons with multiple sclerosis (PwMS) have increased postural sway in quiet stance, decreased gait speed and increased fall incidence. Trunk performance has been implicated in postural control, gait dysfunction, and fall prevention in older adults. However, the relationship of trunk performance to postural control and gait has not been adequately studied in PwMS. OBJECTIVE: To compare trunk muscle structure and performance in PwMS to healthy age and gendered-matched controls (HC); to determine the effects of isometric trunk endurance testing on postural control in both populations; and to determine the relationship of trunk performance with postural control, gait and step activity in PwMS. METHODS: Fifteen PwMS and HC completed ultrasound imaging of trunk muscles, 10 m walk test, isometric trunk endurance tests, and postural sway test. Participants wore a step activity monitor for 7 days. RESULTS: PwMS had worse isometric trunk endurance compared to HC. PwMS trunk flexion endurance negatively correlated to several postural control measures and positively correlated to gait speed and step activity. CONCLUSIONS: Clinicians should consider evaluation and interventions directed at impaired trunk endurance in PwMS.

Continued recovery in an adult with cerebellar ataxia.

BACKGROUND AND PURPOSE: The authors previously reported on the functional recovery of an adult with chronic, severe ataxia secondary to traumatic brain injury (TBI) after 28 sessions of trunk stabilization and locomotor training (LT). The purpose of this case report is to describe this individual's functional abilities 3.5 years after the intervention. CASE DESCRIPTION: Thirteen months post-TBI and not expected to be a functional ambulator, an adult male participated in a trunk stabilization and LT intervention. After the intervention, he continued to exercise in a hospital-based fitness program and received additional physical therapy. Evaluation of balance, gait, trunk performance, self-reported function, and quality of life was performed at 6 weeks (baseline), 1 year, and 3.5 years after completing the intervention. OUTCOMES: Balance, gait, and function improved. Resting left transverse abdominis thickness, measured using ultrasound imaging, increased as did left-side bridge and trunk flexion endurance. He increased community participation and expressed general satisfaction with his overall quality of life. DISCUSSION AND CONCLUSION: In the 3.5 years after participation in an intervention of trunk stabilization and LT this adult became an independent limited community ambulator. Persons with severe ataxia secondary to TBI may continue to improve many years after injury.

Use of trunk stabilization and locomotor training in an adult with cerebellar ataxia: a single system design.

The purpose of this study is to describe the effects of trunk stabilization training and locomotor training (LT) using body-weight support on a treadmill (BWST) and overground walking on balance, gait, self-reported function, and trunk muscle performance in an adult with severe ataxia secondary to brain injury. There are no studies on the effectiveness of these combined interventions in persons with ataxia. The subject was a 23-year-old male who had a traumatic brain injury 13 months prior. An A-B-A withdrawal single-system design was used. Outcome measures were Berg Balance Test (BBT), timed unsupported stance, Functional Ambulation Category (FAC), 10-meter walk test (10-MWT), Outpatient Physical Therapy Improvement in Movement Assessment Log (OPTIMAL), transverse abdominis (TrA) thickness, and isometric trunk endurance tests. Performance on the BBT, timed unsupported stance, FAC, 10-MWT, and OPTIMAL each improved after 10 weeks of intervention. In additions, TrA symmetry at rest improved as did right side-bridge endurance time. LT, using BWST and overground walking, and trunk stabilization training may be effective in improving balance, gait, function, and trunk performance in individuals with severe ataxia. Further research with additional subjects is indicated.

A rehabilitative ultrasound imaging investigation of lateral abdominal muscle thickness in healthy aging adults.

PURPOSE: Rehabilitative ultrasound imaging (RUSI) is used to evaluate lateral abdominal muscle size and function during the abdominal drawing-in maneuver (ADIM), an exercise used to improve lumbar spine stability. Little is known about the size and performance of these muscles in healthy aging adults. The purpose of this study was to investigate, using RUSI, the size and symmetry of the lateral abdominal muscles bilaterally at rest and during the ADIM in healthy older adults and the reliability of these measurements. METHODS: Three ultrasound images of the right and left lateral abdominal muscles were taken at rest and during the ADIM in 12 healthy older adults. Thickness of the transversus abdominis muscles (TrA), internal oblique (IO), and external oblique (EO) were measured for all images. Intraclass correlation coefficients were computed using model 3, form 1 (ICC3,1). Two ratios of the abdominal muscles were calculated in the relaxed and contracted states. Paired t-tests were used to compare relaxed muscle thickness to contracted muscle thickness for all 3 muscles for each side. To test further for interactions of side and contractile state, 2 x 2 repeated measures ANOVAs were performed. Side-to-side differences in absolute and relative thickness were assessed with paired t-tests for the TrA and IO muscles. Absolute and relative side-to-side muscle symmetry indices were computed for each muscle at rest. RESULTS: There was a significant difference in muscle thickness between the contracted and relaxed states for both the TrA and IO. There was no significant difference between left/right muscle thickness for the TrA or IO at rest or during the ADIM. The TrA nearly doubled in size while thickness of the IO + EO stayed relatively constant during the ADIM. Reliability for absolute muscle thickness was generally excellent: ICCs3,1 ranged from 0.95 to 1.00 for intra-image reliability; 0.77 to 0.97 for inter-image reliability. CONCLUSIONS: These findings support symmetrical and preferential activation of the TrA during the ADIM in healthy older adults. Continued research on the use of RUSI as a tool for both assessment and intervention in older adults is needed.