A pilot observational study of gait changes over time before and after an unplanned hospital visit in long-term care residents with dementia.

BACKGROUND: Older adults with dementia living in long-term care (LTC) have high rates of hospitalization. Two common causes of unplanned hospital visits for LTC residents are deterioration in health status and falls. Early detection of health deterioration or increasing falls risk may present an opportunity to intervene and prevent hospitalization. There is some evidence that impairments in older adults' gait, such as reduced gait speed, increased variability, and poor balance may be associated with hospitalization. However, it is not clear whether changes in gait are observable and measurable before an unplanned hospital visit and whether these changes persist after the acute medical issue has been resolved. The objective of this study was to examine gait changes before and after an unplanned acute care hospital visit in people with dementia. METHODS: We performed a secondary analysis of quantitative gait measures extracted from videos of natural gait captured over time on a dementia care unit and collected information about unplanned hospitalization from health records. RESULTS: Gait changes in study participants before hospital visits were characterized by decreasing stability and step length, and increasing step variability, although these changes were also observed in participants without hospital visits. In an age and sex-adjusted mixed effects model, gait speed and step length declined more quickly in those with a hospital visit compared to those without. CONCLUSIONS: These results provide preliminary evidence that clinically meaningful longitudinal gait changes may be captured by repeated non-invasive gait monitoring, although a larger study is needed to identify changes specific to future medical events.

The Toronto older adults gait archive: video and 3D inertial motion capture data of older adults' walking.

We introduce the Toronto Older Adults Gait Archive, a gait dataset of 14 older adults containing 2D video recordings, and 2D (video pose tracking algorithms) and 3D (inertial motion capture) joint locations of the lower body. Participants walked for 60 seconds. We also collected participants' scores on four clinical assessments of gait and balance, namely the Tinneti performance-oriented mobility assessment (POMA-gait and -balance), the Berg balance scale (BBS), and the timed-up-and-go (TUG). Three human pose tracking models (Alphapose, OpenPose, and Detectron) were used to detect body joint positions in 2D video frames and a number of gait parameters were computed using 2D video-based and 3D motion capture data. To show an example usage of our datasets, we performed a correlation analysis between the gait variables and the clinical scores. Our findings revealed that the temporal but not the spatial or variability gait variables from both systems had high correlations to clinical scores. This dataset can be used to evaluate, or to enhance vision-based pose-tracking models to the specifics of older adults' walking.

Indoor Location Data for Tracking Human Behaviours: A Scoping Review.

Real-time location systems (RTLS) record locations of individuals over time and are valuable sources of spatiotemporal data that can be used to understand patterns of human behaviour. Location data are used in a wide breadth of applications, from locating individuals to contact tracing or monitoring health markers. To support the use of RTLS in many applications, the varied ways location data can describe patterns of human behaviour should be examined. The objective of this review is to investigate behaviours described using indoor location data, and particularly the types of features extracted from RTLS data to describe behaviours. Four major applications were identified: health status monitoring, consumer behaviours, developmental behaviour, and workplace safety/efficiency. RTLS data features used to analyse behaviours were categorized into four groups: dwell time, activity level, trajectory, and proximity. Passive sensors that provide non-uniform data streams and features with lower complexity were common. Few studies analysed social behaviours between more than one individual at once. Less than half the health status monitoring studies examined clinical validity against gold-standard measures. Overall, spatiotemporal data from RTLS technologies are useful to identify behaviour patterns, provided there is sufficient richness in location data, the behaviour of interest is well-characterized, and a detailed feature analysis is undertaken.

Gait changes over time in hospitalized older adults with advanced dementia: Predictors of mobility change.

People with dementia are at risk of mobility decline. In this study, we measured changes in quantitative gait measures over a maximum 10-week period during the course of a psychogeriatric admission in older adults with dementia, with the aims to describe mobility changes over the duration of the admission, and to determine which factors were associated with this change. Fifty-four individuals admitted to a specialized dementia inpatient unit participated in this study. A vision-based markerless motion capture system was used to record participants' natural gait. Mixed effect models were developed with gait measures as the dependent variables and clinical and demographic variables as predictors. We found that gait stability, step time, and step length decreased, and step time variability and step length variability increased over 10 weeks. Gait stability of men decreased more than that of women, associated with an increased sacrum mediolateral range of motion over time. In addition, the sacrum mediolateral range of motion decreased in those with mild neuropsychiatric symptoms over 10 weeks, but increased in those with more severe neuropsychiatric symptoms. Our study provides evidence of worsening of gait mechanics and control over the course of a hospitalization in older adults with dementia. Quantitative gait monitoring in hospital environments may provide opportunities to intervene to prevent adverse events, decelerate mobility decline, and monitor rehabilitation outcomes.

Concurrent validity of human pose tracking in video for measuring gait parameters in older adults: a preliminary analysis with multiple trackers, viewing angles, and walking directions.

BACKGROUND: Many of the available gait monitoring technologies are expensive, require specialized expertise, are time consuming to use, and are not widely available for clinical use. The advent of video-based pose tracking provides an opportunity for inexpensive automated analysis of human walking in older adults using video cameras. However, there is a need to validate gait parameters calculated by these algorithms against gold standard methods for measuring human gait data in this population. METHODS: We compared quantitative gait variables of 11 older adults (mean age = 85.2) calculated from video recordings using three pose trackers (AlphaPose, OpenPose, Detectron) to those calculated from a 3D motion capture system. We performed comparisons for videos captured by two cameras at two different viewing angles, and viewed from the front or back. We also analyzed the data when including gait variables of individual steps of each participant or each participant's averaged gait variables. RESULTS: Our findings revealed that, i) temporal (cadence and step time), but not spatial and variability gait measures (step width, estimated margin of stability, coefficient of variation of step time and width), calculated from the video pose tracking algorithms correlate significantly to that of motion capture system, and ii) there are minimal differences between the two camera heights, and walks viewed from the front or back in terms of correlation of gait variables, and iii) gait variables extracted from AlphaPose and Detectron had the highest agreement while OpenPose had the lowest agreement. CONCLUSIONS: There are important opportunities to evaluate models capable of 3D pose estimation in video data, improve the training of pose-tracking algorithms for older adult and clinical populations, and develop video-based 3D pose trackers specifically optimized for quantitative gait measurement.

A systematic review of center of pressure measures to quantify gait changes in older adults.

Measures of gait center of pressure (COP) can be recorded using simple available technologies in clinical settings and thus can be used to characterize gait quality in older adults and its relationship to falls. The aim of this systematic review was to investigate the association between measures of gait COP and aging and falls. A comprehensive search of electronic databases including MEDLINE, Embase, Cochrane Central Register of Controlled Trials, CINAHL (EBSCO), Ageline (EBSCO) and Scopus was performed. The initial search yielded 2809 papers. After removing duplicates and applying study inclusion/exclusion criteria, 34 papers were included in the review. Gait COP has been examined during three tasks: normal walking, gait initiation, and obstacle negotiation. The majority of studies examined mean COP position and velocity as outcome measures. Overall, gait in older adults was characterized by more medial COP trajectory in normal walking and lower average anterior-posterior and medio-lateral COP displacements and velocity in both gait initiation and obstacle crossing. Moreover, findings suggest that Tai chi training can enhance older adults' balance control during gait initiation as demonstrated by greater COP backward, medial and forward shift in all three phases of gait initiation. These findings should be interpreted cautiously due to inadequacy of evidence as well as methodological limitations of the studies such as small sample size, limited numbers of 'fallers', lack of a control group, and lack of interpretation of COP outcomes with respect to fall risk. COP measures can be adopted to assess fall-related gait changes in older adults but more complex measures of COP that reveal the dynamic nature of COP behavior in step-to-step variations are needed to adequately characterize gait changes in older adults.

Effect of Different Placement of Heel Rockers on Lower-Limb Joint Biomechanics in Healthy Individuals.

BACKGROUND: Rocker shoes are commonly prescribed to healthy and pathologic populations to decrease stress on the lower limbs. An optimal rocker shoe design must consider both toe and heel rockers. Heel rockers are as effective as toe rockers in relieving foot plantar pressures. However, most studies have focused on the position of toe rockers. The aim of this study was to assess the effect of different heel rocker apex placements on lower-limb kinetics and kinematics. METHODS: Eighteen healthy females participated in this study. Three pairs of rocker shoes with rocker apex positions anterior to the medial malleolus (shoe A), at the medial malleolus (shoe B), and posterior to the medial malleolus (shoe C) were fabricated and then compared with a flat shoe (shoe D). Kinetic and kinematic data were collected, and lower-extremity joint ranges of motion and moments were calculated. RESULTS: Ankle range of motion was increased by shoe C ( P = .04) during initial contact and by shoe A ( P = .02) during single-limb support. Peak knee moment was significantly larger for shoes A and B ( P < .05) during single-limb support. CONCLUSIONS: Results showed that forward and backward shifting of the heel rocker apex could change the knee moment and ankle joint range of motion in the stance phase of gait. Therefore, placement of the heel rocker in a rocker-bottom shoe can be manipulated to promote the desired lower-limb motion, at least in healthy individuals.

Influence of heel design in an orthopedic shoe on ground reaction forces during walking.

BACKGROUND: One of the treatments prescribed for musculoskeletal patients is orthopedic shoe. The use of an orthopedic shoe is thought to produce a more typical ground reactive force pattern. OBJECTIVES: This study was designed to determine the influence of three heel designs of an orthopedic shoe on the ground reaction forces during walking in healthy subjects. STUDY DESIGN: Quasi-experimental. METHOD: In total, 30 healthy adults (12 males, 18 females) walked at a self-selected pace for six trials in each of the three shoe conditions having three different heels which included the following: standard heel, beveled heel, and positive posterior heel flare. For each trial, ground reaction force parameters were recorded using a force plate. RESULTS: Repeated measures analysis of variance indicated that the impact force was significantly reduced for the positive posterior heel flare condition by 8% and 13% compared with standard and beveled heels, respectively (p < 0.001). The first peak of vertical force showed a significant reduction in the beveled heel by 5% and 4% compared with the standard heel and the positive posterior heel flare, respectively (p < 0.001). Loading rate was significantly reduced in the beveled heel and the positive posterior heel flare conditions (p < 0.05). CONCLUSION: Positive posterior heel flare reduced impact force due to its geometry flexibility, while a beveled heel reduced first peak of vertical force. The findings of this study show that the shape of the heel therefore has the potential to modify impact loads during walking. CLINICAL RELEVANCE: This study provides new evidence that by changing shape in the heel of orthopedic shoe impact loads are reduced during walking. Thus, these findings indicate that use of heel design may be beneficial for various musculoskeletal disorders, including key public health problems.

Reliability of ultrasound thickness measurement of the abdominal muscles during clinical isometric endurance tests.

The study was designed to evaluate the intra-examiner reliability of ultrasound (US) thickness measurement of abdominal muscles activity when supine lying and during two isometric endurance tests in subjects with and without Low back pain (LBP). A total of 19 women (9 with LBP, 10 without LBP) participated in the study. Within-day reliability of the US thickness measurements at supine lying and the two isometric endurance tests were assessed in all subjects. The intra-class correlation coefficient (ICC) was used to assess the relative reliability of thickness measurement. The standard error of measurement (SEM), minimal detectable change (MDC) and the coefficient of variation (CV) were used to evaluate the absolute reliability. Results indicated high ICC scores (0.73-0.99) and also small SEM and MDC scores for within-day reliability assessment. The Bland-Altman plots of agreement in US measurement of the abdominal muscles during the two isometric endurance tests demonstrated that 95% of the observations fall between the limits of agreement for test and retest measurements. Together the results indicate high intra-tester reliability for the US measurement of the thickness of abdominal muscles in all the positions tested. According to the study's findings, US imaging can be used as a reliable method for assessment of abdominal muscles activity in supine lying and the two isometric endurance tests employed, in participants with and without LBP.

An alternative approach to describing agility in sports through establishment of a relationship between velocity and radius of curvature.

Agility is an essential part of many athletic activities. Currently, agility drill duration is the sole criterion used for evaluation of agility performance. The relationship between drill duration and factors such as acceleration, deceleration and change of direction, however, has not been fully explored. This paper provides a mathematical description of the relationship between velocity and radius of curvatures in an agility drill through implementation of a power law (PL). Two groups of skilled and unskilled participants performed a cyclic forward/backward shuttle agility test. Kinematic data was recorded using motion capture system at a sampling rate of 200 Hz. The logarithmic relationship between tangential velocity and radius of curvature of participant trajectories in both groups was established using the PL. The slope of the regression line was found to be 0.26 and 0.36, for the skilled and unskilled groups, respectively. The magnitudes of regression line slope for both groups were approximately 0.3 which is close to the expected 1/3 value. Results are an indication of how the PL could be implemented in an agility drill thus opening the way for establishment of a more representative measure of agility performance instead of drill duration.

The effect of patellofemoral bracing on walking in individuals with patellofemoral pain syndrome.

BACKGROUND: Although knee braces are used by individuals with patellofemoral pain syndrome, the effect of patellofemoral bracing on knee flexion during walking has not been elucidated. AIM: The purpose of this study was to evaluate the effect of patellofemoral bracing on sagittal plane knee joint kinematics and temporal spatial parameters during walking in individuals with patellofemoral pain syndrome. STUDY DESIGN: Quasi-experimental. METHODS: Ten subjects with a diagnosis of patellofemoral pain syndrome were fitted with a knee brace incorporating an infrapatellar strap. Testing was performed at baseline and after 6 weeks of use. Gait analysis and a visual analog scale were used to assess outcomes in this study. RESULTS: A 59.6% decrease in pain was reported by using bracing. Bracing significantly improved speed of walking (p ≤ 0.001) and step length (p ≤ 0.001). The mean cadence was also increased following 6 weeks of patellofemoral brace use, but this was not significant (p = 0.077). Knee flexion angles improved during initial contact, loading response, and mid-swing (p ≤ 0.001) after 6 weeks of patellofemoral brace use. CONCLUSION: Knee orthoses resulted in decreased pain, improved temporal spatial parameters (speed of walking and step length), and increased knee flexion angles during ambulation in patients with patellofemoral pain syndrome.