Age and gender differences in seven tests of functional mobility

BACKGROUND: The objective of this study was to examine age and gender differences in seven tests of functional mobility. METHODS: The study included 50 young participants aged 20 to 39 years, and 684 older participants aged 75 to 98 years. Functional mobility measures included the coordinated stability test, the near tandem balance test, the six metre walk test, the sit to stand test with five repetitions, the alternate step test and the stair ascent and descent tests. RESULTS: Older participants performed significantly worse than the younger participants in all of the functional mobility tests (p < 0.001), with the older women performing worse than the older men in all of the tests (p < 0.05). Significant correlations were found within the older group among all the functional mobility tests scores (r = 0.24–0.87, p < 0.001), and between functional mobility performance and age (r = 0.14–0.35, p < 0.001). People with arthritis and stroke performed worse than people without these conditions in these tests. CONCLUSION: This study provides a normative database for performance of young and older community-dwelling people in a battery of validated and reliable functional mobility tests. The results confirm age-related differences in functional mobility between young and older adults

Force-Controlled Balance Perturbations Associated with Falls in Older People: A Prospective Cohort Study

Balance recovery from an unpredictable postural perturbation can be a challenging task for many older people and poor recovery could contribute to their risk of falls. This study examined associations between responses to unpredictable perturbations and fall risk in older people. 242 older adults (80.064.4 years) underwent assessments of stepping responses to multi-directional force-controlled waist-pull perturbations. Participants returned monthly falls calendars for the subsequent 12 months. Future falls were associated with lower force thresholds for stepping in the posterior and lateral but not anterior directions. Those with lower posterior force thresholds for stepping were 68% more likely to fall at home than those with higher force thresholds for stepping. These results suggest that amount of force that can be withstood following an unpredictable balance perturbation predicts future falls in community-dwelling older adults. Perturbations in the posterior direction best discriminated between future fallers and non-fallers

A consensus guide to using functional near-infrared spectroscopy in posture and gait research

BACKGROUND: Functional near-infrared spectroscopy (fNIRS) is increasingly used in the field of posture and gait to investigate patterns of cortical brain activation while people move freely. fNIRS methods, analysis and reporting of data vary greatly across studies which in turn can limit the replication of research, interpretation of findings and comparison across works. RESEARCH QUESTION AND METHODS: Considering these issues, we propose a set of practical recommendations for the conduct and reporting of fNIRS studies in posture and gait, acknowledging specific challenges related to clinical groups with posture and gait disorders. RESULTS: Our paper is organized around three main sections: 1) hardware set up and study protocols, 2) artefact removal and data processing and, 3) outcome measures, validity and reliability; it is supplemented with a detailed checklist. SIGNIFICANCE: This paper was written by a core group of members of the International Society for Posture and Gait Research and posture and gait researchers, all experienced in fNIRS research, with the intent of assisting the research community to lead innovative and impactful fNIRS studies in the field of posture and gait, whilst ensuring standardization of research

Shoes on trial: Does a safe shoe exist for older people?

More than 80% of older people report foot problems and, as a result, tend to wear unstructured footwear that moulds to the shape of their deformed feet. While these unstructured shoes are deemed comfortable, it has been speculated that they contribute to home falls and hip fractures in the older population [1]. However, as walking barefoot or in socks has also been associated with an increased risk of falls in older people [2], we need to design safe but comfortable shoes for older people to wear in and around the home

Optimizing footwear for older people at risk of falls

Footwear influences balance and the subsequent risk of slips, trips, and falls by altering somatosensory feedback to the foot and ankle and modifying frictional conditions at the shoe/floor interface. Walking indoors barefoot or in socks and walking indoors or outdoors in high-heel shoes have been shown to increase the risk of falls in older people. Other footwear characteristics such as heel collar height, sole hardness, and tread and heel geometry also influence measures of balance and gait. Because many older people wear suboptimal shoes, maximizing safe shoe use may offer an effective fall prevention strategy. Based on findings of a systematic literature review, older people should wear shoes with low heels and firm slip-resistant soles both inside and outside the home. Future research should investigate the potential benefits of tread sole shoes for preventing slips and whether shoes with high collars or flared soles can enhance balance when challenging tasks are undertaken

Impaired depth perception and restricted pitch head movement increase obstacle contacts when dual-tasking in older people

Background.Trips are the largest contributor to falls in older people, yet little is known about the underlying physiological mechanisms for safe obstacle negotiation. The aims of the study were to determine (i) the effect of a secondary visual task on obstacle contacts when older people negotiated an obstacle course and (ii) physiological factors associated with obstacle contacts.Methods.Thirty community-living adults aged 65 years and older walked along a 14.5-m walkway containing 21 obstacles with and without a secondary task. The secondary task required participants to call out a series of letters presented in front of them at head height and the suit of a playing card framed on the sidewall. Obstacle contacts, secondary task errors, eye peak-to-peak pitch amplitude and head peak-to-peak pitch amplitude (PA-H), and head angle in pitch were measured. Participants also completed assessments of sensorimotor function and balance.Results.Compared with the obstacle-only trials, participants performed the dual-task trials more slowly (p <. 001), contacted more obstacles (p =. 032), showed greater PA-H (p <. 001), and an extended head position (p <. 001). Most participants also made secondary task errors. Regression analysis revealed that depth perception was the only significant determinant of obstacle contacts (explaining 20.6% of the variance) in the obstacle-only task and that depth perception and PA-H were independent and significant determinants of obstacle contacts (explaining 42.3% of the variance) in the dual task.Conclusion.The findings demonstrate the importance of depth perception and head movement for safe negotiation of obstacles in older people and suggest that depth perception in particular should form part of fall risk assessments

Perception of the postural vertical and falls in older people

Background: Research on the relationship between vestibular function and falls in older people is sparse. The perception of the postural vertical (PPV) provides an indicator measure of vestibular (otolith) function in the absence of visual input and diminished somatosensory feedback. Objective: This study examined whether impaired PPV is associated with falls in this group. Methods: One hundred and ninetyfive people aged 70 plus years stood blindfolded on a motorised platform that could be tilted in the roll plane and attempted to adjust it so that their bodies were aligned to the vertical. Somatosensory feedback was minimised as the base and vertical support surfaces on the tilting platform were covered in thick soft foam rubber. PPV error from true vertical and PPV variability (°) were calculated. Participants also underwent an assessment of distal tactile sensitivity and the physiological profile assessment (PPA); fallers were defined as those who had one or more falls during a prospective 12-month follow-up period. Results: Eighty-eight participants (45%) reported falling in the follow-up year. Increased PPV error and variability were correlated with increased lateral sway in a condition of absent visual input and reduced foot somatosensory feedback (eyes closed/foam; r range = 0.16–0.20, p<0.05) and with composite PPA fall risk scores (r range = 0.22–0.26, p<0.05). PPV variability was a significant and independent predictor of falls after adjusting for the composite PPA scores, age and gender [adjusted RR = 1.42 (1.01–1.98)]. Conclusions: Older people with increased PPV variability are at increased risk of falls. These findings indicate that assessment of PPV may augment fall risk assessments in older people

Gait profiles as indicators of domain-specific impairments in executive control across neurodevelopmental disorders

In neurodevelopmental disorders, unique profiles of executive control and attention appear to co-occur with poor motor coordination. However, less is known about how syndrome-specific cognitive profiles interact with motor control and impact behavioural outcomes in neurodevelopmental disorders such as Williams syndrome (WS) and Down syndrome (DS). Here we aimed to examine the extent to which specific components of executive function interact with gait control when performing cognitive dual-tasks (verbal fluency, digit span) in WS and DS. Spatiotemporal gait characteristics and intra-individual variability of gait were assessed in individuals with WS who were matched on spatial ability to individuals with DS, and chronologically age (CA) matched controls. During the concurrent verbal fluency task, the WS group had greater dual-task costs on spatiotemporal gait parameters and variability than CA controls. Conversely, individuals with DS had selective gait interference during the concurrent digit span task when compared to CA controls, but only under increased demands on cognitive control where there was greater variability in step timing in DS. The interrelationships between cognitive-motor interference and behavioural measures of executive functioning appeared to differentiate between WS and DS, and emphasise the importance of task modality in unpacking the executive control profile in these neurodevelopmental disorders. These findings support the notion that associated cerebellar-cortico abnormalities may produce quite distinct profiles of executive control across cognitive and motor domains that impact on behavioural outcomes in neurodevelopmental disorders.12 page(s

Older people contact more obstacles when wearing multifocal glasses and performing a secondary visual task

OBJECTIVES: To determine whether wearing multifocal glasses affects obstacle avoidance and eye and head movements during walking with and without a secondary visual task in older people. DESIGN: Randomized order, cross-over, controlled comparison. SETTING: Falls laboratory, medical research institute. PARTICIPANTS: Thirty community-living adults aged 65 and older. MEASUREMENTS: Obstacle contacts, secondary-task errors, average head angle (HA) in pitch, and peak-to-peak pitch amplitude of the eye (PA-E) and the head (PA-H) were assessed during obstacle-only and dual-task trials that required participants to read a series of letters presented in front of them at eye level under multifocal and single-lens glasses conditions. RESULTS: When wearing multifocal lens glasses, participants performed the obstacle-only trials more slowly (P=.004) and contacted more obstacles in the dual-task trials (P=.001) than when wearing single-lens glasses. For the dual task trials under the multifocal glasses condition, greater PA-E was associated with more obstacle contacts (ρ=0.409, P=.02) and greater PA-H was associated with more secondary-task errors (ρ=0.583 P=.002). Lower HA was associated with more secondary-task errors (ρ=0.608, P=.002) and increased PA-H (ρ=0.426, P=.02). CONCLUSION: The findings demonstrate that older adults contact more obstacles while walking with their attention divided when wearing multifocal glasses. This is probably because of a failure to adopt a compensatory increase in pitch head movement, resulting in blurred vision of obstacles viewed through the lower segments of multifocal glasses

The effect of lower limb muscle fatigue on obstacle negotiation during walking in older adults

Middle-aged adults with painful hip conditions show balance impairments that are consistent with an increased risk of falls. Pathological changes at the hip, accompanied by pain, may accelerate pre-existing age-related balance deficits present in midlife. To consider the influence of pain alone, we investigated the effects of acute experimental hip muscle pain on dynamic single-limb balance in middle-aged adults. Thirty-four healthy adults aged 40-60 years formed two groups (Group-1: n=16; Group-2: n=18). Participants performed four tasks: Reactive Sideways Stepping (ReactSide); Star Excursion Balance Test (SEBT); Step Test; Single-Limb Squat; before and after an injection of hypertonic saline into the right gluteus medius muscle (Group-1) or ∼5min rest (Group-2). Balance measures included the range and standard deviation of centre of pressure (CoP) movement in mediolateral and anterior-posterior directions, and CoP total path velocity (ReactSide, Squat); reach distance (SEBT); and number of completed steps (Step Test). Data were assessed using three-way analysis of variance. Motor outcomes were altered during the second repetition of tasks irrespective of exposure to experimental hip muscle pain or rest, with reduced SEBT anterior reach (-1.2±4.1cm, P=0.027); greater step number during Step Test (1.5±1.7 steps,