The Impact of Different Types of Assistive Devices on Gait Measures and Safety in Huntington's Disease

BACKGROUND: Gait and balance impairments lead to frequent falls and injuries in individuals with Huntington's disease (HD). Assistive devices (ADs) such as canes and walkers are often prescribed to prevent falls, but their efficacy is unknown. We systematically examined the effects of different types of ADs on quantitative gait measures during walking in a straight path and around obstacles. METHODS: Spatial and temporal gait parameters were measured in 21 subjects with HD as they walked across a GAITRite walkway under 7 conditions (i.e., using no AD and 6 commonly prescribed ADs: a cane, a weighted cane, a standard walker, and a 2, 3 or 4 wheeled walker). Subjects also were timed and observed for number of stumbles and falls while walking around two obstacles in a figure-of-eight pattern. RESULTS: Gait measure variability (i.e., coefficient of variation), an indicator of fall risk, was consistently better when using the 4WW compared to other ADs. Subjects also walked the fastest and had the fewest number of stumbles and falls when using the 4WW in the figure-of-eight course. Subjects walked significantly slower using ADs compared to no AD both across the GAITRite and in the figure-of-eight. Measures reflecting gait stability and safety improved with the 4WW but were made worse by some other ADs

Altering gait by way of stimulation of the plantar surface of the foot: the immediate effect of wearing textured insoles in older fallers

Background: Evidence suggests that textured insoles can alter gait and standing balance by way of enhanced plantar tactile stimulation. However, to date, this has not been explored in older people at risk of falling. This study investigated the immediate effect of wearing textured insoles on gait and double-limb standing balance in older fallers.Methods: Thirty older adults >65 years (21 women, mean [SD] age 79.0 [7.1]), with self-reported history of ≥2 falls in the previous year, conducted tests of level-ground walking over 10 m (GAITRite system), and double-limb standing with eyes open and eyes closed over 30 seconds (Kistler force platform) under two conditions: wearing textured insoles (intervention) and smooth (control) insoles in their usual footwear.Results: Wearing textured insoles caused significantly lower gait velocity (P = 0.02), step length (P = 0.04) and stride length (P = 0.03) compared with wearing smooth insoles. No significant differences were found in any of the balance parameters (P > 0.05).Conclusions: A textured insole worn by older adults with a history of falls significantly lowers gait velocity, step length and stride length, suggesting that this population may not have an immediate benefit from this type of intervention. The effects of prolonged wear remain to be investigated

Quantitative gait analysis under dual-task in older people with mild cognitive impairment: a reliability study

<p>Abstract</p> <p>Background</p> <p>Reliability of quantitative gait assessment while dual-tasking (walking while doing a secondary task such as talking) in people with cognitive impairment is unknown. Dual-tasking gait assessment is becoming highly important for mobility research with older adults since better reflects their performance in the basic activities of daily living. Our purpose was to establish the test-retest reliability of assessing quantitative gait variables using an electronic walkway in older adults with mild cognitive impairment (MCI) under single and dual-task conditions.</p> <p>Methods</p> <p>The gait performance of 11 elderly individuals with MCI was evaluated using an electronic walkway (GAITRite^®System) in two sessions, one week apart. Six gait parameters (gait velocity, step length, stride length, step time, stride time, and double support time) were assessed under two conditions: single-task (sG: usual walking) and dual-task (dG: counting backwards from 100 while walking). Test-retest reliability was determined using intra-class correlation coefficient (ICC). Gait variability was measured using coefficient of variation (CoV).</p> <p>Results</p> <p>Eleven participants (average age = 76.6 years, SD = 7.3) were assessed. They were high functioning (Clinical Dementia Rating Score = 0.5) with a mean Mini-Mental Status Exam (MMSE) score of 28 (SD = 1.56), and a mean Montreal Cognitive Assessment (MoCA) score of 22.8 (SD = 1.23). Under dual-task conditions, mean gait velocity (GV) decreased significantly (sGV = 119.11 ± 20.20 cm/s; dGV = 110.88 ± 19.76 cm/s; p = 0.005). Additionally, under dual-task conditions, higher gait variability was found on stride time, step time, and double support time. Test-retest reliability was high (ICC>0.85) for the six parameters evaluated under both conditions.</p> <p>Conclusion</p> <p>In older people with MCI, variability of time-related gait parameters increased with dual-tasking suggesting cognitive control of gait performance. Assessment of quantitative gait variables using an electronic walkway is highly reliable under single and dual-task conditions. The presence of cognitive impairment did not preclude performance of dual-tasking in our sample supporting that this methodology can be reliably used in cognitive impaired older individuals.</p

Can cognitive enhancers reduce the risk of falls in older people with Mild Cognitive Impairment? A protocol for a randomised controlled double blind trial

<p>Abstract</p> <p>Background</p> <p>Older adults with cognitive problems have a higher risk of falls, at least twice that of cognitively normal older adults. The consequences of falls in this population are very serious: fallers with cognitive problems suffer more injuries due to falls and are approximately five times more likely to be admitted to institutional care. Although the mechanisms of increased fall risk in cognitively impaired people are not completely understood, it is known that impaired cognitive abilities can reduce attentional resource allocation while walking. Since cognitive enhancers, such as cholinesterase inhibitors, improve attention and executive function, we hypothesise that cognitive enhancers may reduce fall risk in elderly people in the early stages of cognitive decline by improving their gait and balance performance due to an enhancement in attention and executive function.</p> <p>Method/Design</p> <p>Double blinded randomized controlled trial with 6 months follow-up in 140 older individuals with Mild Cognitive Impairment (MCI). Participants will be randomized to the intervention group, receiving donepezil, and to the control group, receiving placebo. A block randomization by four and stratification based on fall history will be performed. Primary outcomes are improvements in gait velocity and reduction in gait variability. Secondary outcomes are changes in the balance confidence, balance sway, attention, executive function, and number of falls.</p> <p>Discussion</p> <p>By characterizing and understanding the effects of cognitive enhancers on fall risk in older adults with cognitive impairments, we will be able to pave the way for a new approach to fall prevention in this population. This RCT study will provide, for the first time, information regarding the effect of a medication designed to augment cognitive functioning have on the risk of falls in older adults with Mild Cognitive Impairment. We expect a significant reduction in the risk of falls in this vulnerable population as a function of the reduced gait variability achieved by treatment with cognitive enhancers. This study may contribute to a new approach to prevent and treat fall risk in seniors in early stages of dementia.</p> <p>Trial Registration</p> <p>The protocol for this study is registered with the Clinical Trials Registry, identifier number: NCT00934531 <url>http://www.clinicaltrials.gov</url></p

Nesting habitat and nest site characteristics of the white-bellied sea eagle in the Gippsland lakes region of Victoria, Australia

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Using passive acoustic recording and automated call identification to survey koalas in the southern forests of New South Wales

Cost-effective surveys of low density koala populations are challenging, but technological developments in the acoustics field offer great potential for landscape-scale surveys and monitoring. We assessed passive acoustic recording coupled with automated call identification as a survey method for koalas Phascolarctos cinereus. Surveys targeted areas of previously known koala activity based on scat surveys in southern forests of New South Wales where a low density of koalas is suspected.We set 24 Song Meters to record at night over a two week period (~3,696 hours) in the koala breeding season (October/November) in Murrah Flora Reserve. Recordings were scanned by a koala call recogniser and “matches” were manually verified. Across the 24 sites, 522 validated koala bellows were recorded at 21 sites (87.5 % detection rate). Three environmental variables had most influence on detection probability of koalas, including nightly rainfall (-ve), nightly temperature (-ve) and topographic position (lower on ridges). Calling activity peaked at midnight. Sustained site occupancy, at least in the short-term, was apparent as under optimal conditions (no rain) koalas were recorded, on average, for > 50 % of survey nights rather than for just a few nights.We suggest that only a modest survey effort (4-5 nights) in the breeding season, on nights with < 3 mm of rain, is required to achieve 90-95 % probability of koala call detection in an area of low koala density. Comparison with scat surveys at the same sites revealed that detection rates were more than three times greater with acoustic surveys. Technological advances will continue to provide improvements for wildlife survey, and perhaps most importantly, for collecting much needed long-term data to assess trends in occupancy or other population attributes over time.</p