Centre of pressure modulations in double support effectively counteract anteroposterior perturbations during gait

Background: Cognitive frailty (CF), defined as the simultaneous presence of cognitive impairment and physical frailty, is a clinical symptom in early-stage dementia with promise in assessing the risk of dementia. The purpose of this study was to use wearables to determine the most sensitive digital gait biomarkers to identify CF. Methods: Of 121 older adults (age = 78.9 ± 8.2 years, body mass index = 26.6 ± 5.5 kg/m2) who were evaluated with a comprehensive neurological exam and the Fried frailty criteria, 41 participants (34%) were identified with CF and 80 participants (66%) were identified without CF. Gait performance of participants was assessed under single task (walking without cognitive distraction) and dual task (walking while counting backward from a random number) using a validated wearable platform. Participants walked at habitual speed over a distance of 10 m. A validated algorithm was used to determine steady-state walking. Gait parameters of interest include steady-state gait speed, stride length, gait cycle time, double support, and gait unsteadiness. In addition, speed and stride length were normalized by height. Results: Our results suggest that compared to the group without CF, the CF group had deteriorated gait performances in both single-task and dual-task walking (Cohen’s effect size d = 0.42–0.97, p < 0.050). The largest effect size was observed in normalized dual-task gait speed (d = 0.97, p < 0.001). The use of dual-task gait speed improved the area under the curve (AUC) to distinguish CF cases to 0.76 from 0.73 observed for the single-task gait speed. Adding both single-task and dual-task gait speeds did not noticeably change AUC. However, when additional gait parameters such as gait unsteadiness, stride length, and double support were included in the model, AUC was improved to 0.87. Conclusions: This study suggests that gait performances measured by wearable sensors are potential digital biomarkers of CF among older adults. Dual-task gait and other detailed gait metrics provide value for identifying CF above gait speed alone. Future studies need to examine the potential benefits of gait performances for early diagnosis of CF and/or tracking its severity over time.

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Effect of centre of pressure and stiffness effect of porous pivoted curved slider bearings using couple stress fluid model

10.1063/5.0025468 ◽

2020 ◽

Author(s):

Nisha ◽

A. Govindarajan

Keyword(s):

Couple Stress ◽

Fluid Model ◽

Couple Stress Fluid ◽

Centre Of Pressure ◽

Slider Bearings

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Effects of Torso Pitch Motion on Energy Efficiency of Biped Robot Walking

Applied Sciences ◽

10.3390/app11052342 ◽

2021 ◽

Vol 11 (5) ◽

pp. 2342

Author(s):

Long Li ◽

Zhongqu Xie ◽

Xiang Luo ◽

Juanjuan Li

Keyword(s):

Energy Efficiency ◽

Energy Consumption ◽

Biped Robot ◽

Gait Pattern ◽

Pattern Generation ◽

Biped Robots ◽

Pitch Motion ◽

Double Support ◽

Gait Parameters ◽

Support Phase

Gait pattern generation has an important influence on the walking quality of biped robots. In most gait pattern generation methods, it is usually assumed that the torso keeps vertical during walking. It is very intuitive and simple. However, it may not be the most efficient. In this paper, we propose a gait pattern with torso pitch motion (TPM) during walking. We also present a gait pattern with torso keeping vertical (TKV) to study the effects of TPM on energy efficiency of biped robots. We define the cyclic gait of a five-link biped robot with several gait parameters. The gait parameters are determined by optimization. The optimization criterion is chosen to minimize the energy consumption per unit distance of the biped robot. Under this criterion, the optimal gait performances of TPM and TKV are compared over different step lengths and different gait periods. It is observed that (1) TPM saves more than 12% energy on average compared with TKV, and the main factor of energy-saving in TPM is the reduction of energy consumption of the swing knee in the double support phase and (2) the overall trend of torso motion is leaning forward in double support phase and leaning backward in single support phase, and the amplitude of the torso pitch motion increases as gait period or step length increases.

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The Feasibility and Effectiveness of Wearable Sensor Technology in the Management of Elderly Diabetics with Foot Ulcer Remission: A Proof-Of-Concept Pilot Study with Six Cases

Gerontology ◽

10.1159/000513729 ◽

2021 ◽

pp. 1-10

Author(s):

Chenzhen Du ◽

Hongyan Wang ◽

Heming Chen ◽

Xiaoyun Fan ◽

Dongliang Liu ◽

...

Keyword(s):

Odds Ratio ◽

Stride Length ◽

Wearable Sensors ◽

Foot Ulcer ◽

Wearable Devices ◽

Foot Ulcers ◽

Diabetic Patients ◽

Wearable Sensor ◽

Double Support ◽

Gait Parameters

Aims: Using specials wearable sensors, we explored changes in gait and balance parameters, over time, in elderly patients at high risk of diabetic foot, wearing different types of footwear. This assessed the relationship between gait and balance changes in elderly diabetic patients and the development of foot ulcers, in a bid to uncover potential benefits of wearable devices in the prognosis and management of the aforementioned complication. Methods: A wearable sensor-based monitoring system was used in middle-elderly patients with diabetes who recently recovered from neuropathic plantar foot ulcers. A total of 6 patients (age range: 55–80 years) were divided into 2 groups: the therapeutic footwear group (n = 3) and the regular footwear (n = 3) group. All subjects were assessed for gait and balance throughout the study period. Walking ability and gait pattern were assessed by allowing participants to walk normally for 1 min at habitual speed. The balance assessment program incorporated the “feet together” standing test and the instrumented modified Clinical Test of Sensory Integration and Balance. Biomechanical information was monitored at least 3 times. Results: We found significant differences in stride length (p < 0.0001), stride velocity (p < 0.0001), and double support (p < 0.0001) between the offloading footwear group (OG) and the regular footwear group on a group × time interaction. The balance test embracing eyes-open condition revealed a significant difference in Hip Sway (p = 0.004), COM Range ML (p = 0.008), and COM Position (p = 0.004) between the 2 groups. Longitudinally, the offloading group exhibited slight improvement in the performance of gait parameters over time. The stride length (odds ratio 3.54, 95% CI 1.34–9.34, p = 0.018) and velocity (odds ratio 3.13, 95% CI 1.19–8.19, p = 0.033) of OG patients increased, converse to the double-support period (odds ratio 6.20, 95% CI 1.97–19.55, p = 0.002), which decreased. Conclusions: Special wearable devices can accurately monitor gait and balance parameters in patients in real time. The finding reveals the feasibility and effectiveness of advanced wearable sensors in the prevention and management of diabetic foot ulcer and provides a solid background for future research. In addition, the development of foot ulcers in elderly diabetic patients may be associated with changes in gait parameters and the nature of footwear. Even so, larger follow-up studies are needed to validate our findings.

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Effects of low back pain on balance performance in elderly people: a systematic review and meta-analysis

European Review of Aging and Physical Activity ◽

10.1186/s11556-021-00263-z ◽

2021 ◽

Vol 18 (1) ◽

Author(s):

Le Ge ◽

Chuhuai Wang ◽

Haohan Zhou ◽

Qiuhua Yu ◽

Xin Li

Keyword(s):

Systematic Review ◽

Low Back Pain ◽

Back Pain ◽

Elderly People ◽

Meta Analysis ◽

Cochrane Library ◽

Original Research ◽

Low Back ◽

Centre Of Pressure ◽

Balance Performance

Abstract Background Research suggests that individuals with low back pain (LBP) may have poorer motor control compared to their healthy counterparts. However, the sample population of almost 90% of related articles are young and middle-aged people. There is still a lack of a systematic review about the balance performance of elderly people with low back pain. This study aimed to conduct a systematic review and meta-analysis to understand the effects of LBP on balance performance in elderly people. Methods This systematic review and meta-analysis included a comprehensive search of PubMed, Embase, and Cochrane Library databases for full-text articles published before January 2020. We included the articles that 1) investigated the elderly people with LBP; 2) assessed balance performance with any quantifiable clinical assessment or measurement tool and during static or dynamic activity; 3) were original research. Two independent reviewers screened the relevant articles, and disagreements were resolved by a third reviewer. Results Thirteen case-control studies comparing balance performance parameters between LBP and healthy subjects were included. The experimental group (LBP group) was associated with significantly larger area of centre of pressure movement (P < 0.001), higher velocity of centre of pressure sway in the anteroposterior and mediolateral directions (P = 0.01 and P = 0.02, respectively), longer path length in the anteroposterior direction (P < 0.001), slower walking speed (P = 0.05), and longer timed up and go test time (P = 0.004) than the control group. Conclusion The results showed that balance performance was impaired in elderly people with LBP. We should pay more attention to the balance control of elderly people with LBP.

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Effects of task difficulty on centre of pressure excursion and its inter-trial variability in acrobatic gymnastics pyramid performance

Sports Biomechanics ◽

10.1080/14763141.2020.1770322 ◽

2020 ◽

pp. 1-16

Author(s):

Pureza Leal del Ojo ◽

Pablo Floría ◽

Andrew J Harrison ◽

Luis Arturo Gómez-Landero

Keyword(s):

Task Difficulty ◽

Centre Of Pressure

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Increased double support variability in elderly female fallers with vestibular asymmetry

Gait & Posture ◽

10.1016/j.gaitpost.2015.02.019 ◽

2015 ◽

Vol 41 (3) ◽

pp. 820-824 ◽

Cited By ~ 6

Author(s):

Johan Larsson ◽

Eva Ekvall Hansson ◽

Michael Miller

Keyword(s):

Double Support ◽

Elderly Female ◽

Vestibular Asymmetry

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‘Mammoth Vessels and Coriolis Force’

Journal of Navigation ◽

10.1017/s0373463300018774 ◽

1971 ◽

Vol 24 (2) ◽

pp. 252-253

Author(s):

G. R. G. Lewison

Keyword(s):

Northern Hemisphere ◽

Coriolis Force ◽

Forward Speed ◽

Centre Of Pressure ◽

Drift Angle ◽

Centre Of Gravity ◽

Resistive Forces ◽

Yaw Angle

Mr. Anneveld's paper (24, 50) would have us believe that the effects of coriolis force on a ship may become appreciable as ship size increases. It is true that the drift angle does increase as the ship's size increases, because the coriolis force given by equation (1) increases as (length)3·5 and the resistive forces increase as (length)3 (on the assumption of geometrically similar ships and Froude scaling). However there is a fundamental flaw in his argument because equation (2) only applies to a vessel with zero forward speed. Moreover the effect of coriolis drift will also be to induce a yaw angle on the ship (because the centre of pressure is forward of the centre of gravity, where the coriolis force may be assumed to act) and this will automatically cause the helmsman or autopilot to apply starboard rudder in the northern hemisphere. This will immediately produce a force on the ship in the port direction, i.e. opposing coriolis force.

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Preliminary study of regionalised centre-of-pressure analysis in patients with juvenile idiopathic arthritis

Journal of Foot and Ankle Research ◽

10.1186/1757-1146-5-s1-o15 ◽

2012 ◽

Vol 5 (S1) ◽

Cited By ~ 1

Author(s):

Gordon J Hendry ◽

Danny Rafferty ◽

Ruth Semple ◽

Janet M Gardner-Medwin ◽

Debbie E Turner ◽

...

Keyword(s):

Juvenile Idiopathic Arthritis ◽

Centre Of Pressure ◽

Preliminary Study ◽

Pressure Analysis

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Split-Belt Treadmill Adaptation Transfers to Overground Walking in Persons Poststroke

Neurorehabilitation and Neural Repair ◽

10.1177/1545968309332880 ◽

2009 ◽

Vol 23 (7) ◽

pp. 735-744 ◽

Cited By ~ 159

Author(s):

Darcy S. Reisman ◽

Robert Wityk ◽

Kenneth Silver ◽

Amy J. Bastian

Keyword(s):

Step Length ◽

Overground Walking ◽

Double Support ◽

Context Switching ◽

Before And After ◽

Partial Transfer ◽

And Gender ◽

Double Support Time ◽

Support Time ◽

Control Locomotion

Background and Objective. Following stroke, subjects retain the ability to adapt interlimb symmetry on the split-belt treadmill. Critical to advancing our understanding of locomotor adaptation and its usefulness in rehabilitation is discerning whether adaptive effects observed on a treadmill transfer to walking over ground. We examined whether aftereffects following split-belt treadmill adaptation transfer to overground walking in healthy persons and those poststroke. Methods. Eleven poststroke and 11 age-matched and gender-matched healthy subjects walked over ground before and after walking on a split-belt treadmill. Adaptation and aftereffects in step length and double support time were calculated. Results. Both groups demonstrated partial transfer of the aftereffects observed on the treadmill ( P < .001) to overground walking ( P < .05), but the transfer was more robust in the subjects poststroke ( P < .05). The subjects with baseline asymmetry after stroke improved in asymmetry of step length and double limb support ( P = .06). Conclusions. The partial transfer of aftereffects to overground walking suggests that some shared neural circuits that control locomotion for different environmental contexts are adapted during split-belt treadmill walking. The larger adaptation transfer from the treadmill to overground walking in the stroke survivors may be due to difficulty adjusting their walking pattern to changing environmental demands. Such difficulties with context switching have been considered detrimental to function poststroke. However, we propose that the persistence of improved symmetry when changing context to overground walking could be used to advantage in poststroke rehabilitation.

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