Perceptual Modification of the Built Environment to Influence Behavior Associated with Physical Activity: Quasi-Experimental Field Studies of a Stair Banister Illusion.

PubMed

Masters, Rich; Capio, Catherine; Poolton, Jamie; Uiga, Liis

2018-06-01

Re-engineering the built environment to influence behaviors associated with physical activity potentially provides an opportunity to promote healthier lifestyles at a population level. Here we present evidence from two quasi-experimental field studies in which we tested a novel, yet deceptively simple, intervention designed to alter perception of, and walking behavior associated with, stairs in an urban area. Our objectives were to examine whether adjusting a stair banister has an influence on perceptions of stair steepness or on walking behavior when approaching the stairs. In study 1, we asked participants (n = 143) to visually estimate the steepness of a set of stairs viewed from the top, when the stair banister was adjusted so that it converged with or diverged from the stairs (± 1.91°) or remained neutral (± 0°). In study 2, the walking behavior of participants (n = 36) was filmed as they approached the stairs to descend, unaware of whether the banister converged, diverged, or was neutral. In study 1, participants estimated the stairs to be steeper if the banister diverged from, rather than converged with, the stairs. The effect was greater when participants were unaware of the adjustment. In study 2, walking speed was significantly slower when the banister diverged from, rather than converged with, the stairs. These findings encourage us to speculate about the potential to economically re-engineer features of the built environment to provide opportunities for action (affordances) that invite physical activity behavior or even promote safer navigation of the environment.

Is there sufficient evidence regarding signage-based stair use interventions? A sequential meta-analysis

PubMed Central

Bauman, Adrian; Milton, Karen; Kariuki, Maina; Fedel, Karla; Lewicka, Mary

2017-01-01

Objective The proliferation of studies using motivational signs to promote stair use continues unabated, with their oft-cited potential for increasing population-level physical activity participation. This study examined all stair use promotional signage studies since 1980, calculating pre-estimates and post-estimates of stair use. The aim of this project was to conduct a sequential meta-analysis to pool intervention effects, in order to determine when the evidence base was sufficient for population-wide dissemination. Design Using comparable data from 50 stair-promoting studies (57 unique estimates) we pooled data to assess the effect sizes of such interventions. Results At baseline, median stair usage across interventions was 8.1%, with an absolute median increase of 2.2% in stair use following signage-based interventions. The overall pooled OR indicated that participants were 52% more likely to use stairs after exposure to promotional signs (adjusted OR 1.52, 95% CI 1.37 to 1.70). Incremental (sequential) meta-analyses using z-score methods identified that sufficient evidence for stair use interventions has existed since 2006, with recent studies providing no further evidence on the effect sizes of such interventions. Conclusions This analysis has important policy and practice implications. Researchers continue to publish stair use interventions without connection to policymakers' needs, and few stair use interventions are implemented at a population level. Researchers should move away from repeating short-term, small-scale, stair sign interventions, to investigating their scalability, adoption and fidelity. Only such research translation efforts will provide sufficient evidence of external validity to inform their scaling up to influence population physical activity. PMID:29183924

NorthEast view; Interior view of stair enclosure and stair from ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

North-East view; Interior view of stair enclosure and stair from platform to main passenger terminal - North Philadelphia Station, 2900 North Broad Street, on northwest corner of Broad Street & Glenwood Avenue, Philadelphia, Philadelphia County, PA

Mind Your Step: the Effects of Mobile Phone Use on Gaze Behavior in Stair Climbing.

PubMed

Ioannidou, Flora; Hermens, Frouke; Hodgson, Timothy L

2017-01-01

Stair walking is a hazardous activity and a common cause of fatal and non-fatal falls. Previous studies have assessed the role of eye movements in stair walking by asking people to repeatedly go up and down stairs in quiet and controlled conditions, while the role of peripheral vision was examined by giving participants specific fixation instructions or working memory tasks. We here extend this research to stair walking in a natural environment with other people present on the stairs and a now common secondary task: using one's mobile phone. Results show that using the mobile phone strongly draws one's attention away from the stairs, but that the distribution of gaze locations away from the phone is little influenced by using one's phone. Phone use also increased the time needed to walk the stairs, but handrail use remained low. These results indicate that limited foveal vision suffices for adequate stair walking in normal environments, but that mobile phone use has a strong influence on attention, which may pose problems when unexpected obstacles are encountered.

Computer simulation of stair falls to investigate scenarios in child abuse.

PubMed

Bertocci, G E; Pierce, M C; Deemer, E; Aguel, F

2001-09-01

To demonstrate the usefulness of computer simulation techniques in the investigation of pediatric stair falls. Since stair falls are a common falsely reported injury scenario in child abuse, our specific aim was to investigate the influence of stair characteristics on injury biomechanics of pediatric stair falls by using a computer simulation model. Our long-term goal is to use knowledge of biomechanics to aid in distinguishing between accidents and abuse. A computer simulation model of a 3-year-old child falling down stairs was developed using commercially available simulation software. This model was used to investigate the influence that stair characteristics have on biomechanical measures associated with injury risk. Since femur fractures occur in unintentional and abuse scenarios, biomechanical measures were focused on the lower extremities. The number and slope of steps and stair surface friction and elasticity were found to affect biomechanical measures associated with injury risk. Computer simulation techniques are useful for investigating the biomechanics of stair falls. Using our simulation model, we determined that stair characteristics have an effect on potential for lower extremity injuries. Although absolute values of biomechanical measures should not be relied on in an unvalidated model such as this, relationships between accident-environment factors and biomechanical measures can be studied through simulation. Future efforts will focus on model validation.

Anticipatory kinematics and muscle activity preceding transitions from level-ground walking to stair ascent and descent.

PubMed

Peng, Joshua; Fey, Nicholas P; Kuiken, Todd A; Hargrove, Levi J

2016-02-29

The majority of fall-related accidents are during stair ambulation-occurring commonly at the top and bottom stairs of each flight, locations in which individuals are transitioning to stairs. Little is known about how individuals adjust their biomechanics in anticipation of walking-stair transitions. We identified the anticipatory stride mechanics of nine able-bodied individuals as they approached transitions from level ground walking to stair ascent and descent. Unlike prior investigations of stair ambulation, we analyzed two consecutive "anticipation" strides preceding the transitions strides to stairs, and tested a comprehensive set of kinematic and electromyographic (EMG) data from both the leading and trailing legs. Subjects completed ten trials of baseline overground walking and ten trials of walking to stair ascent and descent. Deviations relative to baseline were assessed. Significant changes in mechanics and EMG occurred in the earliest anticipation strides analyzed for both ascent and descent transitions. For stair descent, these changes were consistent with observed reductions in walking speed, which occurred in all anticipation strides tested. For stair ascent, subjects maintained their speed until the swing phase of the latest anticipation stride, and changes were found that would normally be observed for decreasing speed. Given the timing and nature of the observed changes, this study has implications for enhancing intent recognition systems and evaluating fall-prone or disabled individuals, by testing their abilities to sense upcoming transitions and decelerate during locomotion. Copyright © 2016 Elsevier Ltd. All rights reserved.

A wheelchair with lever propulsion control for climbing up and down stairs.

PubMed

Sasaki, Kai; Eguchi, Yosuke; Suzuki, Kenji

2016-08-01

This study proposes a novel stair-climbing wheelchair based on lever propulsion control using the human upper body. Wheelchairs are widely used as supporting locomotion devices for people with acquired lower limb disabilities. However, steps and stairs are critical obstacles to locomotion, which restrict their activities when using wheelchairs. Previous research focused on power-assisted, stair-climbing wheelchairs, which were large and heavy due to its large actuators and mechanisms. In the previous research, we proposed a wheelchair with lever propulsion mechanism and presented its feasibility of climbing up the stairs. The developed stair-climbing wheelchair consists of manual wheels with casters for planar locomotion and a rotary-leg mechanism based on lever propulsion that is capable of climbing up stairs. The wheelchair also has a passive mechanism powered by gas springs for posture transition to shift the user's center of gravity between the desired positions for planar locomotion and stair-climbing. In this paper, we present an advanced study on both climbing up and going down using lever propulsion control by the user's upper body motion. For climbing down the stairs, we reassembled one-way clutches used for the rotary-leg mechanism to help a user climb down the stairs through lever operation. We also equipped the wheelchair with sufficient torque dampers. The frontal wheels were fixed while climbing down the stairs to ensure safety. Relevant experiments were then performed to investigate its performance and verify that the wheelchair users can operate the proposed lever propulsion mechanism.

Stair Descending Exercise Using a Novel Automatic Escalator: Effects on Muscle Performance and Health-Related Parameters

PubMed Central

Paschalis, Vassilis; Theodorou, Anastasios A.; Panayiotou, George; Kyparos, Antonios; Patikas, Dimitrios; Grivas, Gerasimos V.; Nikolaidis, Michalis G.; Vrabas, Ioannis S.

2013-01-01

A novel automatic escalator was designed, constructed and used in the present investigation. The aim of the present investigation was to compare the effect of two repeated sessions of stair descending versus stair ascending exercise on muscle performance and health-related parameters in young healthy men. Twenty males participated and were randomly divided into two equal-sized groups: a stair descending group (muscle-damaging group) and a stair ascending group (non-muscle-damaging group). Each group performed two sessions of stair descending or stair ascending exercise on the automatic escalator while a three week period was elapsed between the two exercise sessions. Indices of muscle function, insulin sensitivity, blood lipid profile and redox status were assessed before and immediately after, as well as at day 2 and day 4 after both exercise sessions. It was found that the first bout of stair descending exercise caused muscle damage, induced insulin resistance and oxidative stress as well as affected positively blood lipid profile. However, after the second bout of stair descending exercise the alterations in all parameters were diminished or abolished. On the other hand, the stair ascending exercise induced only minor effects on muscle function and health-related parameters after both exercise bouts. The results of the present investigation indicate that stair descending exercise seems to be a promising way of exercise that can provoke positive effects on blood lipid profile and antioxidant status. PMID:23437093

Toe spatiotemporal differences between transition steps when ascending shorter flight stairways of different heights.

PubMed

Ajisafe, Toyin; Wu, Jianhua; Geil, Mark

2017-03-01

Studies have typically treated the first and second floor-to-stair transition steps (TS1 and TS2) as one stride. However, because the foot is devoid of plantar cutaneous input from the stair surface at TS1, these steps may have different toe spatiotemporal profiles, and resultantly, different susceptibilities to a trip and/or a fall. This study compared vertical toe clearance, forward velocity, and their respective variability magnitudes between TS1 and TS2 when ascending stairs of different heights. Twenty young adults (seven males and 13 females) (21.68 ± 2.49 years; 169.70 ± 9.56 cm; 63.91 ± 9.62 kg) negotiated an intervening three-step staircase placed midpoint on a 10 m walkway. There were three stair heights: low stairs (LS), medium stairs (MS), and high stairs (HS). Vertical toe clearance, forward velocity, and their variability magnitudes were calculated. Vertical toe clearance was only higher (P < 0.05) at TS1 than TS2 in the medium and high stairs. Vertical toe clearance was more variable (P < 0.05) in the low compared to medium stairs. Also, forward toe velocity was greater at TS1 than TS2, but was lower in the medium and high stairs. The locomotor system appeared cautious by exaggerating vertical toe clearance at both TS1 and TS2 only in low stairs, possibly due to higher forward toe velocity. If the exaggeration strategy consistently persists, this finding may suggest decreased trip or fall risk at both TS1 and TS2 only when transitioning onto low stairs. Copyright © 2016 Elsevier Ltd. All rights reserved.

Is there sufficient evidence regarding signage-based stair use interventions? A sequential meta-analysis.

PubMed

Bauman, Adrian; Milton, Karen; Kariuki, Maina; Fedel, Karla; Lewicka, Mary

2017-11-28

The proliferation of studies using motivational signs to promote stair use continues unabated, with their oft-cited potential for increasing population-level physical activity participation. This study examined all stair use promotional signage studies since 1980, calculating pre-estimates and post-estimates of stair use. The aim of this project was to conduct a sequential meta-analysis to pool intervention effects, in order to determine when the evidence base was sufficient for population-wide dissemination. Using comparable data from 50 stair-promoting studies (57 unique estimates) we pooled data to assess the effect sizes of such interventions. At baseline, median stair usage across interventions was 8.1%, with an absolute median increase of 2.2% in stair use following signage-based interventions. The overall pooled OR indicated that participants were 52% more likely to use stairs after exposure to promotional signs (adjusted OR 1.52, 95% CI 1.37 to 1.70). Incremental (sequential) meta-analyses using z-score methods identified that sufficient evidence for stair use interventions has existed since 2006, with recent studies providing no further evidence on the effect sizes of such interventions. This analysis has important policy and practice implications. Researchers continue to publish stair use interventions without connection to policymakers' needs, and few stair use interventions are implemented at a population level. Researchers should move away from repeating short-term, small-scale, stair sign interventions, to investigating their scalability, adoption and fidelity. Only such research translation efforts will provide sufficient evidence of external validity to inform their scaling up to influence population physical activity. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Promoting stair use: single versus multiple stair-riser messages.

PubMed

Webb, Oliver J; Eves, Frank F

2005-09-01

Message banners attached to stair risers produced a significant increase in pedestrian stair use, exceeding effects previously reported for conventional posters. Multiple instances of the same message banner, however, were as effective as banners featuring different messages. Therefore, greater visibility, rather than message variety, appears to account for the superiority of the banner format. Our findings indicate the feasibility of simple stair-use promotion campaigns based around the repetition of a single message.

Amount of balance necessary for the independence of transfer and stair-climbing in stroke inpatients.

PubMed

Fujita, Takaaki; Sato, Atsushi; Ohashi, Yuji; Nishiyama, Kazutaka; Ohashi, Takuro; Yamane, Kazuhiro; Yamamoto, Yuichi; Tsuchiya, Kenji; Otsuki, Koji; Tozato, Fusae

2018-05-01

The purpose of this study was to clarify the amount of balance necessary for the independence of transfer and stair-climbing in stroke patients. This study included 111 stroke inpatients. Simple and multiple regression analyses were conducted to establish the association between the FIM ® instrument scores for transfer or stair-climbing and Berg Balance Scale. Furthermore, receiver operating characteristic curves were used to elucidate the amount of balance necessary for the independence of transfer and stair-climbing. Simple and multiple regression analyses showed that the FIM ® instrument scores for transfer and stair-climbing were strongly associated with Berg Balance Scale. On comparison of the independent and supervision-dependent groups, Berg Balance Scale cut-off values for transfer and stair-climbing were 41/40 and 54/53 points, respectively. On comparison of the independent-supervision and dependent groups, the cut-off values for transfer and stair-climbing were 30/29 and 41/40 points, respectively. The calculated cut-off values indicated the amount of balance necessary for the independence of transfer and stair-climbing, with and without supervision, in stroke patients. Berg Balance Scale has a good discriminatory ability and cut-off values are clinically useful to determine the appropriate independence levels of transfer and stair-climbing in hospital wards. Implications for rehabilitation The Berg Balance Scale's (BBS) strong association with transfer and stair-climbing independence and performance indicates that establishing cut-off values is vitally important for the established use of the BBS clinically. The cut-off values calculated herein accurately demonstrate the level of balance necessary for transfer and stair-climbing independence, with and without supervision, in stroke patients. These criteria should be employed clinically for determining the level of independence for transfer and stair-climbing as well as for setting balance training goals aimed at improving transfer and stair-climbing.

Point-of-Decision Signs and Stair Use in a University Worksite Setting: General Versus Specific Messages.

PubMed

Eckhardt, Mary R; Kerr, Jacqueline; Taylor, Wendell C

2015-01-01

This study tested the effectiveness of two point-of-decision signs to increase stair use and investigated message content by comparing signs with general and specific messages. This study used a quasi-experimental time series design, including a 2-week baseline period: 2 weeks with a general message and 2 weeks with a specific message. The signs were placed in an eight-story university building. The subjects comprised all adults entering the building. During the study, 2997 observations of stair/elevator choice were made. A stair-prompt sign with a general message and a sign with a specific message served as the interventions. Observers measured stair/elevator choice, demographics, and traffic volume. Logistic regression analyses were employed, adjusting for covariates. The specific sign intervention showed significantly increased odds of stair use compared to baseline (odds ratio [OR] = 2.04, 95% confidence interval [CI] = 1.46-2.84). The odds of stair use were also significantly greater with the specific sign than the general sign (OR = 1.57, 95% CI = 1.13-2.20). Only the specific sign significantly increased stair use. The results indicate that a specific message may be more effective at promoting stair use.

Can motivational signs prompt increases in incidental physical activity in an Australian health-care facility?

PubMed

Marshall, A L; Bauman, A E; Patch, C; Wilson, J; Chen, J

2002-12-01

This study aimed to evaluate whether a stair-promoting signed intervention could increase the use of the stairs over the elevator in a health-care facility. A time-series design was conducted over 12 weeks. Data were collected before, during and after displaying a signed intervention during weeks 4-5 and 8-9. Evaluation included anonymous counts recorded by an objective unobtrusive motion-sensing device of people entering the elevator or the stairs. Self-report data on stair use by hospital staff were also collected. Stair use significantly increased after the first intervention phase (P = 0.02), but after the intervention was removed stair use decreased back towards baseline levels. Moreover, stair use did not significantly change after the re-introduction of the intervention. Lastly, stair use decreased below the initial baseline level during the final weeks of evaluation. Furthermore, there was no significant change in self-reported stair use by hospital staff. Therefore, the signed intervention aimed at promoting an increase in incidental physical activity produced small brief effects, which were not maintained. Further research is required to find more effective 'point of choice' interventions to increase incidental physical activity participation with more sustainable impact.

7. Photocopied August 1971 from Photo 11480, Stairs Station Special ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. Photocopied August 1971 from Photo 11480, Stairs Station Special Folder, Engineering Department, Utah Power and Light Co., Salt Lake City, Utah. STAIRS HYDRO-ELECTRIC PLANT (1600 KW) STATION AND PENSTOCK, NOVEMBER 1914. - Utah Power & Light Company, Stairs Hydroelectric Station, Holladay, Salt Lake County, UT

SPARKy - Spring Ankle with Regenerative Kinetics to Build a New Generation of Transtibial Prostheses

DTIC Science & Technology

2010-07-01

walking on inclines/declines, and ascending/descending stairs We are able to walk continuously over ground and can walk up and down slopes and... stairs . Walking up a slope and ascending stairs needs to be improved, adding extra propulsion. The propulsion walking down stairs needs to be...bodied subjects walking on flat even surfaces, inclines/declines, and ascending/descending stairs – In Process 4. Using able bodied test data, a

Frontal Joint Dynamics when Initiating Stair Ascent from a Walk versus a Stand

PubMed Central

Vallabhajosula, Srikant; Yentes, Jennifer M.; Stergiou, Nicholas

2011-01-01

Ascending stairs is a challenging activity of daily living for many populations. Frontal plane joint dynamics are critical to understand the mechanisms involved in stair ascension as they contribute to both propulsion and medio-lateral stability. However, previous research is limited to understanding these dynamics while initiating stair ascent from a stand. We investigated if initiating stair ascent from a walk with a comfortable self-selected speed could affect the frontal plane lower-extremity joint moments and powers as compared to initiating stair ascent from a stand and if this difference would exist at consecutive ipsilateral steps on the stairs. Kinematics data using a 3-D motion capture system and kinetics data using two force platforms on the first and third stair treads were recorded simultaneously as ten healthy young adults ascended a custom-built staircase. Data were collected from two starting conditions of stair ascent, from a walk (speed: 1.42±0.21m/s) and from a stand. Results showed that subjects generated greater peak knee abductor moment and greater peak hip abductor moment when initiating stair ascent from a walk. Greater peak joint moments and powers at all joints were also seen while ascending the second ipsilateral step. Particularly, greater peak hip abductor moment was needed to avoid contact of the contralateral limb with the intermediate step by counteracting the pelvic drop on the contralateral side. This could be important for therapists using stair climbing as a testing/training tool to evaluate hip strength in individuals with documented frontal plane abnormalities (i.e. knee and hip osteoarthritis, ACL injury). PMID:22172606

A review of stairway falls and stair negotiation: Lessons learned and future needs to reduce injury.

PubMed

Jacobs, Jesse V

2016-09-01

Stairways are a common location for falls, and they result in a disproportionate risk of death or severe injury. Stairway falls are a significant problem across the lifespan and are often coincident with risky behaviors during stair use. The mechanics of successful stair negotiation for healthy young and older adults have been well described. These studies imply that current stair design does not offer an optimal universal design to meet the needs of older adults or people with health conditions. In addition, impaired stair negotiation associates with more than impaired strength, including functional impairments of cognitive load, sensory function and central motor coordination. Identification of behavioral strategies or stairway environments that assist or hinder recovery from a loss of balance on stairs remains incomplete. Therefore, future studies should investigate the mechanisms of balance recovery on stairs as well as the effectiveness of environmental interventions to mitigate stairway falls and injuries. Potential areas for evaluation may include modifying stair dimensions, surfaces, handrails, visual cues, and removing distractors of attention. Studies should also evaluate combinatorial interventions on person-related factors, such as behavioral interventions to decrease risky behaviors during stair use as well as interventions on cognitive, sensory, and motor functions relevant to stair use. Moreover, future studies should take advantage of new technologies to record stair use outside the laboratory in order to identify people or locations at risk for stairway falls. Such studies would inform the potential for broad-spectrum programs that decrease the risk of stairway falls and injuries. Copyright © 2016 The Author. Published by Elsevier B.V. All rights reserved.

Arena entry stair to left and stair to arena top ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Arena entry stair to left and stair to arena top level entry bridge at right. Drop siding is on second floor of recreation center. - U.S. Naval Base, Pearl Harbor, Bloch Recreation Center & Arena, Between Center Drive & North Road near Nimitz Gate, Pearl City, Honolulu County, HI

The effects of signage and the physical environment on stair usage.

PubMed

Bungum, Tim; Meacham, Mindy; Truax, Nicole

2007-07-01

Physical activity (PA) is a health behavior that most Americans do not participate in at recommended levels. We sought to increase PA by use of motivational signs in selected buildings. Because physical environments are known to influence PA, the relationship of building characteristics and stair usage was also assessed. One pre- and two post-intervention observations were conducted. The proportion of those using the stairs increased from baseline to the second data collection, (chi2 = 39.31, p < 0.01) and baseline to a final data collection (chi2 = 10.1, p < 0.01). Built environment factors, including steps to the next higher floor and the number of floors in the building were consistent predictors of stair use. With signs positioned, the visibility of the stairs while standing in front of elevators became a significant predictor of stair usage. Motivational signs and characteristics of built environments are associated with increased stair usage.

Identification of stair climbing ability levels in community-dwelling older adults based on the geometric mean of stair ascent and descent speed: The GeMSS classifier.

PubMed

Mayagoitia, Ruth E; Harding, John; Kitchen, Sheila

2017-01-01

The aim was to develop a quantitative approach to identify three stair-climbing ability levels of older adults: no, somewhat and considerable difficulty. Timed-up-and-go test, six-minute-walk test, and Berg balance scale were used for statistical comparison to a new stair climbing ability classifier based on the geometric mean of stair speeds (GeMSS) in ascent and descent on a flight of eight stairs with a 28° pitch in the housing unit where the participants, 28 (16 women) urban older adults (62-94 years), lived. Ordinal logistic regression revealed the thresholds between the three ability levels for each functional test were more stringent than thresholds found in the literature to classify walking ability levels. Though a small study, the intermediate classifier shows promise of early identification of difficulties with stairs, in order to make timely preventative interventions. Further studies are necessary to obtain scaling factors for stairs with other pitches. Copyright © 2016 Elsevier Ltd. All rights reserved.

Valgus-varus motion of the knee in normal level walking and stair climbing.

PubMed

Yu, B; Stuart, M J; Kienbacher, T; Growney, E S; An, K-N

1997-07-01

OBJECTIVE: The knee valgus-varus moment and the knee angles were compared between normal level walking and stair climbing. DESIGN: Ten healthy subjects were tested for ascent, descent, and level walking. BACKGROUND: An understanding of the normal valgus-varus motion of the knee during stair climbing is needed to apply biomechanical analysis of stair climbing as a evaluation tool for knee osteoarthritis patients. METHODS: A motion analysis system, three force plates, and a flight of stairs were used to collect kinematic and kinetic data. The knee angles and moments were calculated from the collected kinematic and kinetic data. RESULTS: The knee varus angle for the maximum knee valgus moments in stair climbing was significantly greater than that in level walking. The knee valgus moment was significantly correlated to ground reaction forces and knee valgus-varus angle during stair climbing and level walking. CONCLUSIONS: There is a coupling between the knee valgus-varus motion and flexion-extension motion. Ground reaction forces are the major contributors to the within-subject variation in the knee valgus-varus moment during stair climbing and level walking. The knee valgus-varus angle is a major contributor to the between-subject variation in the knee valgus moment during stair climbing and level walking.

Review Article: Increasing physical activity with point-of-choice prompts--a systematic review.

PubMed

Nocon, Marc; Müller-Riemenschneider, Falk; Nitzschke, Katleen; Willich, Stefan N

2010-08-01

Stair climbing is an activity that can easily be integrated into everyday life and has positive health effects. Point-of-choice prompts are informational or motivational signs near stairs and elevators/escalators aimed at increased stair climbing. The aim of this review was to assess the effectiveness of point-of-choice prompts for the promotion of stair climbing. In a systematic search of the literature, studies that assessed the effectiveness of point-of-choice prompts to increase the rate of stair climbing in the general population were identified. No restrictions were made regarding the setting, the duration of the intervention, or the kind of message. A total of 25 studies were identified. Point-of-choice prompts were predominantly posters or stair-riser banners in public traffic stations, shopping malls or office buildings. The 25 studies reported 42 results. Of 10 results for elevator settings, only three reported a significant increase in stair climbing, whereas 28 of 32 results for escalator settings reported a significant increase in stair climbing. Overall, point-of-choice prompts are able to increase the rate of stair climbing, especially in escalator settings. In elevator settings, point-of-choice prompts seem less effective. The long-term efficacy and the most efficient message format have yet to be determined in methodologically rigorous studies.

Frontal joint dynamics when initiating stair ascent from a walk versus a stand.

PubMed

Vallabhajosula, Srikant; Yentes, Jennifer M; Stergiou, Nicholas

2012-02-02

Ascending stairs is a challenging activity of daily living for many populations. Frontal plane joint dynamics are critical to understand the mechanisms involved in stair ascension as they contribute to both propulsion and medio-lateral stability. However, previous research is limited to understanding these dynamics while initiating stair ascent from a stand. We investigated if initiating stair ascent from a walk with a comfortable self-selected speed could affect the frontal plane lower-extremity joint moments and powers as compared to initiating stair ascent from a stand and if this difference would exist at consecutive ipsilateral steps on the stairs. Kinematics data using a 3-D motion capture system and kinetics data using two force platforms on the first and third stair treads were recorded simultaneously as ten healthy young adults ascended a custom-built staircase. Data were collected from two starting conditions of stair ascent, from a walk (speed: 1.42 ± 0.21 m/s) and from a stand. Results showed that subjects generated greater peak knee abductor moment and greater peak hip abductor moment when initiating stair ascent from a walk. Greater peak joint moments and powers at all joints were also seen while ascending the second ipsilateral step. Particularly, greater peak hip abductor moment was needed to avoid contact of the contralateral limb with the intermediate step by counteracting the pelvic drop on the contralateral side. This could be important for therapists using stair climbing as a testing/training tool to evaluate hip strength in individuals with documented frontal plane abnormalities (i.e. knee and hip osteoarthritis, ACL injury). Copyright © 2011 Elsevier Ltd. All rights reserved.

Effect of health-promoting posters placed on the platforms of two train stations in Copenhagen, Denmark, on the choice between taking the stairs or the escalators: a secondary publication.

PubMed

Iversen, M K; Händel, M N; Jensen, E N; Frederiksen, P; Heitmann, B L

2007-06-01

The purpose of this study was to determine whether posters placed on the platforms of two train stations in Copenhagen, promoting use of the stairs, would encourage people to use the stairs rather than the adjacent escalator. An additional purpose was to see if the effect of the intervention was maintained for a week after the poster was removed. The number of people using stairs and escalators at Copenhagen Central Station and Østerport Train Station in Copenhagen was recorded before and during posters promoting stair use were placed on the platforms, and a week after the posters were removed. Two years after the posters were removed, data were collected for 1 week at Østerport Train Station (long-term post-intervention). At Copenhagen Central Station, the overall stair use increased from 12% before the intervention to 16% (P<0.0001) during the intervention, giving an odds ratio (OR) of 1.5 for stair use. At Østerport Train Station in Copenhagen, the overall stair use increased from 23 to 31% during the intervention (P<0.0001), and dropped to 27% (P<0.0001) after the intervention (during the intervention, OR=1.5 (P<0.0001); after the intervention, OR=1.2 (P<0.0001)). At the long-term post-intervention recording, the overall stair use was 25%, which was not significantly different from the stair use found before the intervention. Posters promoting stair use placed on the platforms of train stations can result in increased stair use, during and after 1 week of intervention, and thereby seem useful only when up and immediately following intervention in changing health-promoting behavior among Danish men and women. These results agree well with results from other countries.

Comparison of metabolic cost and cardiovascular response to stair ascending and descending with walkers and canes in older adults.

PubMed

Foley, Michael; Bowen, Brett

2014-09-01

To compare oxygen cost (mL·kg(-1)·m(-1)) and cardiovascular response (beats/m) and oxygen consumption (mL·kg(-1)·min(-1)) and heart rate (beats/min) to stair ascending and descending with walkers, with canes, and without assistive devices (ADs) in older adults. Descriptive, repeated measures. Indoor stairway. Convenience sample of able-bodied volunteers, non-AD users (N=14; mean age, 63.71 ± 11.7 y; mean body mass, 72.7 ± 14.1 kg; mean height, 165.7 ± 9.2 cm). Participants performed 4 randomized trials of stair ascending and descending at their own self-selected speed with 3 ADs: single-point cane, standard walker (SW), and wheeled walker (WW). They also performed unassisted stair ascending and descending. Each trial consisted of a 5-minute steady-state session followed by a 2-minute data collection period. Steady-state expired ventilations were collected in Douglas bags for metabolic analysis. Oxygen cost (mL·kg(-1)·m(-1)), heart rate (HR) response (beats/m), oxygen consumption (mL·kg(-1)·min(-1)), and HR (beats/min) were compared for each trial of stair ascending and descending using analysis of variance repeated measures (P<.05). Greater oxygen cost (per meter) was found for stair ascending and descending using the single-point cane (121%), SW (217%), and WW (232%) compared with unassisted stair ascending and descending (P<.05). Increased HR response (per meter) was found for stair ascending and descending using the single-point cane (116%), SW (126%), and WW (147%) compared with unassisted stair ascending and descending (P<.05). However, oxygen consumption (per minute) and HR (per minute) were not significantly increased during stair ascending and descending with the ADs compared with unassisted stair ascending and descending. Participants stair ascended and descended at significantly (P<.05) reduced speeds during trials with the ADs. This research should aid clinicians by providing evidence to base recommendations on regarding AD usage when encountering stairs during home and community ambulation. Copyright © 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

A multi-component stair climbing promotional campaign targeting calorific expenditure for worksites; a quasi-experimental study testing effects on behaviour, attitude and intention

PubMed Central

2012-01-01

Background Accumulation of lifestyle physical activity is a current aim of health promotion, with increased stair climbing one public health target. While the workplace provides an opportunity for regular stair climbing, evidence for effectiveness of point-of-choice interventions is equivocal. This paper reports a new approach to worksite interventions, aimed at changing attitudes and, hence, behaviour. Methods Pre-testing of calorific expenditure messages used structured interviews with members of the public (n = 300). Effects of multi-component campaigns on stair climbing were tested with quasi-experimental, interrupted time-series designs. In one worksite, a main campaign poster outlining the amount of calorific expenditure obtainable from stair climbing and a conventional point-of-choice prompt were used (Poster alone site). In a second worksite, additional messages in the stairwell about calorific expenditure reinforced the main campaign (Poster + Stairwell messages site). The outcome variables were automated observations of stair and lift ascent (28,854) and descent (29,352) at baseline and for three weeks after the intervention was installed. Post-intervention questionnaires for employees at the worksites assessed responses to the campaign (n = 253). Analyses employed Analysis of Variance with follow-up Bonferroni t-tests (message pre-testing), logistic regression of stair ascent and descent (campaign testing), and Bonferroni t-tests and multiple regression (follow-up questionnaire). Results Pre-testing of messages based on calorific expenditure suggested they could motivate stair climbing if believed. The new campaign increased stair climbing, with greater effects at the Poster + Stairwell messages site (OR = 1.52, 95% CI = 1.40-1.66) than Posters alone (OR = 1.24, 95% CI = 1.15-1.34). Follow-up revealed higher agreement with two statements about calorific outcomes of stair climbing in the site where they were installed in the stairwell, suggesting more positive attitudes resulted from the intervention. Future intentions for stair use were predicted by motivation by the campaign and beliefs that stair climbing would help weight control. Conclusions Multi-component campaigns that target attitudes and intentions may substantially increase stair climbing at work. PMID:22686243

Step It UP: a multicomponent intervention to increase stair use in a university residence building.

PubMed

Howie, Erin Kaye; Young, Deborah Rohm

2011-01-01

Examine the effects of a multicomponent intervention on stair usage. Nonrandomized controlled intervention. Two multistory university dormitories. Total of 5711 direct observations of university dormitory residents. The 2-week "Step It UP" intervention used poster prompts and fun/competitive challenges with incentives to encourage residents to take the stairs instead of the elevators. Ascending stair and elevator use was directly observed and coded for gender at high traffic times in intervention and control dormitories for 14 nonconsecutive hours over 1 week each at baseline, midintervention, and 1 week postintervention. The proportions of ascending stair and elevator users were compared using χ(2) analyses. Baseline stair use was equal between intervention and control dormitories (24.9% and 27.8%, respectively; χ(2)[1, N  =  1849]  =  .08; p  =  .77). Stair use significantly increased from baseline in the intervention dormitory to 33.24% (χ(2)[1, N  =  2192]  =  18.44; p < .001) compared with no change in the control. Stair use returned to baseline in the intervention dormitory at postintervention (25.4%; χ(2)[1, N  =  2297]  =  .08; p  =  .78). There were no significant differences between genders. This multicomponent, short-duration intervention significantly increased stair usage in a university dormitory relative to the control but was unable to sustain the increase when prompts were removed. Campaigns to sustain stair use are needed. Formative assessment is required to determine what combinations of components may yield the most cost-effective approach for future interventions.

A workplace intervention to promote stair climbing: greater effects in the overweight.

PubMed

Eves, Frank F; Webb, Oliver J; Mutrie, Nanette

2006-12-01

Stair climbing is a lifestyle physical activity that uses more calories per minute than jogging. This study tested an intervention designed to promote stair climbing in a workplace. Because previous studies provide only equivocal evidence of the effects of increased stair climbing in worksites, a formal comparison of the effects of the intervention on stair ascent and descent was made. In a five-story public sector building, a 2-week baseline was followed by 6 weeks of an intervention involving a 23(1/2)- x 16(1/2)-inch poster in the lobby, the same poster and six messages affixed to the stair risers between floors, and an 11(3/4)- x 8(1/4)-inch point-of-choice prompt at the elevators. Stair and elevator choices (n = 26,806) were videotaped throughout and subsequently coded for direction of travel, traveler's sex, and traveler's load. Weight status was coded using silhouettes beside the computer monitor. A significant effect of the intervention on stair climbing was greater in those coded as overweight (+5.4%; odds ratio = 1.33) than in individuals of normal weight (+2.5%; odds ratio = 1.12). Although stair descent was more common than ascent, the intervention had similar effects for both directions of travel. Stair climbing at work has few barriers and seems to be a type of physical activity that is acceptable to overweight individuals. The relatively weak effect of workplace interventions compared with results for public access staircases may reflect uncontrolled effects such as the immediate availability of the elevator for the traveler.

Stair negotiation in women with fibromyalgia: A descriptive correlational study.

PubMed

Collado-Mateo, Daniel; Domínguez-Muñoz, Francisco J; Olivares, Pedro R; Adsuar, José C; Gusi, Narcis

2017-10-01

Walking up and down stairs is a common and important activity of daily living. Women with fibromyalgia often show a reduced ability to perform this task.The objective of this study was to evaluate the test-retest reliability of stair negotiation tasks and to assess the impact of fibromyalgia symptoms on the ability to negotiate stairs.Forty-two women with fibromyalgia participated in this descriptive correlational study. The relevance of the stair negotiation (both walking up and down) was evaluated by assessing its association with the revised version of the fibromyalgia impact questionnaire (FIQ-R) and other health-related variables. Test-retest reliability was also analyzed. The main outcome measures were time spent walking up and down stairs and impact of fibromyalgia, quality of life, number of falls, weight, and lower limb strength and endurance.The intraclass correlation coefficient (ICC) for stair descent was 0.929 whereas that for ascent was 0.972. The score in these tests correlated significantly with the total score for the FIQ-R and the score for many of dimensions and symptoms: that is, physical function, overall impact of fibromyalgia, pain, energy, stiffness, restorative sleep, tenderness, self-perceived balance problems, and sensitivity.Given the importance of the stair negotiation as activity of daily living and the high reliability, both stair ascent and descent tasks may be useful as outcome measures in studies on patients with fibromyalgia.

Stair negotiation in women with fibromyalgia

PubMed Central

Collado-Mateo, Daniel; Domínguez-Muñoz, Francisco J.; Olivares, Pedro R.; Adsuar, José C.; Gusi, Narcis

2017-01-01

Abstract Walking up and down stairs is a common and important activity of daily living. Women with fibromyalgia often show a reduced ability to perform this task. The objective of this study was to evaluate the test–retest reliability of stair negotiation tasks and to assess the impact of fibromyalgia symptoms on the ability to negotiate stairs. Forty-two women with fibromyalgia participated in this descriptive correlational study. The relevance of the stair negotiation (both walking up and down) was evaluated by assessing its association with the revised version of the fibromyalgia impact questionnaire (FIQ-R) and other health-related variables. Test–retest reliability was also analyzed. The main outcome measures were time spent walking up and down stairs and impact of fibromyalgia, quality of life, number of falls, weight, and lower limb strength and endurance. The intraclass correlation coefficient (ICC) for stair descent was 0.929 whereas that for ascent was 0.972. The score in these tests correlated significantly with the total score for the FIQ-R and the score for many of dimensions and symptoms: that is, physical function, overall impact of fibromyalgia, pain, energy, stiffness, restorative sleep, tenderness, self-perceived balance problems, and sensitivity. Given the importance of the stair negotiation as activity of daily living and the high reliability, both stair ascent and descent tasks may be useful as outcome measures in studies on patients with fibromyalgia. PMID:29069023

Autonomous Legged Hill and Stairwell Ascent

DTIC Science & Technology

2011-11-01

environments with little burden to a human operator. Keywords: autonomous robot , hill climbing , stair climbing , sequential composition, hexapod, self...X-RHex robot on a set of stairs with laser scanner, IMU, wireless repeater, and handle payloads. making them useful for both climbing hills and...reconciliation into that more powerful (but restrictive) framework. 1) The Stair Climbing Behavior: RHex robots have been climbing single-flight stairs

Dynamic balance control during stair negotiation for older adults and people with Parkinson disease.

PubMed

Conway, Zachary J; Blackmore, Tim; Silburn, Peter A; Cole, Michael H

2018-06-01

It is well understood that stability during ambulation is reliant upon appropriate control of the trunk segment, but research shows that the rhythmicity of this segment is significantly reduced for people with Parkinson's disease (PD). Given the increased risk associated with stair ambulation, this study investigated whether people with PD demonstrate poorer trunk control during stair ambulation compared with age-matched controls. Trunk accelerations were recorded for twelve PD patients and age-matched controls during stair ascent and descent. Accelerations were used to derive measures of harmonic ratios and root mean square (RMS) acceleration to provide insight into the rhythmicity and amplitude of segmental motion. Compared with what is typically seen during level-ground walking, gait rhythmicity during stair negotiation was markedly reduced for older adults and people with PD. Furthermore, both groups exhibited significantly poorer trunk movements during stair descent compared to stair ascent, suggesting that both populations may face a greater risk of falling during this task. As stair negotiation is a common activity of daily life, the increased risk associated with this task should be considered when working with populations that have an increased risk of falling. Copyright © 2018 Elsevier B.V. All rights reserved.

Proposition of stair climb of a drop using chemical wettability gradient

NASA Astrophysics Data System (ADS)

Seerha, Prabh P. S.; Kumar, Parmod; Das, Arup K.; Mitra, Sushanta K.

2017-07-01

We propose a passive technique for a drop to climb along the staircase textured surface using chemical wettability gradients. The stair structure, droplet configuration, and contact angle gradient are modeled using Lagrangian smoothed particle hydrodynamics. The stair climb efficiency of the droplet is found to be a function of wettability gradient strength. Using analytical balance of actuation and resistive forces across droplets, physical reasons behind stair climbing are established and influencing parameters are identified. Evolution of the droplet shape along with the advancing and the receding contact angles is presented from where instantaneous actuation and hysteresis forces are calculated. Using history of Lagrangian particles, circulation at the foot of stairs and progressing development of the advancing drop front are monitored. Higher efficiency in stair climbing in the case of a bigger sized drop than smaller one is obtained from simulation results and realized from force balance. Difficulty in climbing steeper stairs is also demonstrated to delineate the effect of gravitational pull against the actuation force due to the wettability gradient.

At similar angles, slope walking has a greater fall risk than stair walking.

PubMed

Sheehan, Riley C; Gottschall, Jinger S

2012-05-01

According to the CDC, falls are the leading cause of injury for all age groups with over half of the falls occurring during slope and stair walking. Consequently, the purpose of this study was to compare and contrast the different factors related to fall risk as they apply to these walking tasks. More specifically, we hypothesized that compared to level walking, slope and stair walking would have greater speed standard deviation, greater ankle dorsiflexion, and earlier peak activity of the tibialis anterior. Twelve healthy, young male participants completed level, slope, and stair trials on a 25-m walkway. Overall, during slope and stair walking, medial-lateral stability was less, anterior-posterior stability was less, and toe clearance was greater in comparison to level walking. In addition, there were fewer differences between level and stair walking than there were between level and slope walking, suggesting that at similar angles, slope walking has a greater fall risk than stair walking. Copyright © 2011 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Ground reaction forces on stairs: effects of stair inclination and age.

PubMed

Stacoff, Alex; Diezi, Christian; Luder, Gerhard; Stüssi, Edgar; Kramers-de Quervain, Inès A

2005-01-01

The goals of the study were to compare data of vertical ground reaction force (GRF) parameters during level walking, stair ascent and descent on three different stair inclinations and three different age groups. Twenty healthy subjects of three age groups (young 33.7 years; middle 63.6 years; old 76.5 years) were tested during the seven test conditions with 8-10 repetitions. Vertical forces were measured during two consecutive steps with force plates embedded in the walkway and the staircase. The results showed that during level walking the vertical GRF curves were very regular and repetitive, the trail-to-trial variability and left-right asymmetry of defined test parameters being around 2-5% and 3-5%. During stair ascent the vertical GRF force pattern was found to change slightly compared to level gait, but considerably compared to stair descent. On the steep stair the average vertical load increased up to 1.6 BW, and variability (5-10%) and asymmetry (5-15%) were increased significantly. The steep stair descent condition was found to be the most demanding test showing the largest variability and asymmetry and thus, the least stable gait pattern. Age was found to be a factor which should be considered, because the young age group walked faster and produced larger vertical GRF maxima during level walking and on stair ascent than the middle and old age group. Differences between the middle and old age group were found to be small. The present investigation is the first to provide normative data of GRF parameters on gait variability and symmetry of two consecutive steps during level gait and stair ambulation. It is the intention that the results of this study may be used as a basis for comparison with patient data.

Altered joint moment strategy during stair walking in diabetes patients with and without peripheral neuropathy.

PubMed

Brown, Steven J; Handsaker, Joseph C; Maganaris, Constantinos N; Bowling, Frank L; Boulton, Andrew J M; Reeves, Neil D

2016-05-01

To investigate lower limb biomechanical strategy during stair walking in patients with diabetes and patients with diabetic peripheral neuropathy, a population known to exhibit lower limb muscular weakness. The peak lower limb joint moments of twenty-two patients with diabetic peripheral neuropathy and thirty-nine patients with diabetes and no neuropathy were compared during ascent and descent of a staircase to thirty-two healthy controls. Fifty-nine of the ninety-four participants also performed assessment of their maximum isokinetic ankle and knee joint moment (muscle strength) to assess the level of peak joint moments during the stair task relative to their maximal joint moment-generating capabilities (operating strengths). Both patient groups ascended and descended stairs slower than controls (p<0.05). Peak joint moments in patients with diabetic peripheral neuropathy were lower (p<0.05) at the ankle and knee during stair ascent, and knee only during stair descent compared to controls. Ankle and knee muscle strength values were lower (p<0.05) in patients with diabetic peripheral neuropathy compared to controls, and lower at knee only in patients without neuropathy. Operating strengths were higher (p<0.05) at the ankle and knee in patients with neuropathy during stair descent compared to the controls, but not during stair ascent. Patients with diabetic peripheral neuropathy walk slower to alter gait strategy during stair walking and account for lower-limb muscular weakness, but still exhibit heightened operating strengths during stair descent, which may impact upon fatigue and the ability to recover a safe stance following postural instability. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Does perceived steepness deter stair climbing when an alternative is available?

PubMed

Eves, Frank F; Thorpe, Susannah K S; Lewis, Amanda; Taylor-Covill, Guy A H

2014-06-01

Perception of hill slant is exaggerated in explicit awareness. Proffitt (Perspectives on Psychological Science 1:110-122, 2006) argued that explicit perception of the slant of a climb allows individuals to plan locomotion in keeping with their available locomotor resources, yet no behavioral evidence supports this contention. Pedestrians in a built environment can often avoid climbing stairs, the man-made equivalent of steep hills, by choosing an adjacent escalator. Stair climbing is avoided more by women, the old, and the overweight than by their comparators. Two studies tested perceived steepness of the stairs as a cue that promotes this avoidance. In the first study, participants estimated the steepness of a staircase in a train station (n = 269). Sex, age, height, and weight were recorded. Women, older individuals, and those who were heavier and shorter reported the staircase as steeper than did their comparison groups. In a follow-up study in a shopping mall, pedestrians were recruited from those who chose the stairs and those who avoided them, with the samples stratified for sex, age, and weight status. Participants (n = 229) estimated the steepness of a life-sized image of the stairs they had just encountered, presented on the wall of a vacant shop in the mall. Pedestrians who avoided stair climbing by choosing the escalator reported the stairs as steeper even when demographic differences were controlled. Perceived steepness may to be a contextual cue that pedestrians use to avoid stair climbing when an alternative is available.

The Role of Lower Extremity Joint Powers in Successful Stair Ambulation

DTIC Science & Technology

2011-01-01

written informed consent, all subjects participated in a biomechanical gait assessment during stair ascent walking. A total of 55 markers were used...power generation and vertical COM acceleration (COMA) during stair ascent. Twenty-two healthy individuals underwent a biomechanical gait assessment...DA. An integrated biomechanical analysis of normal stair ascent and descent. J Biomech 1988;21:733–44. [6] Zachazewski JE, Riley PO, Krebs DE

Architectural design and physical activity: an observational study of staircase and elevator use in different buildings.

PubMed

Bassett, David R; Browning, Ray; Conger, Scott A; Wolff, Dana L; Flynn, Jennifer I

2013-05-01

The indoor built environment has the potential to influence levels of physical activity. However, the extent to which architectural design in commercial buildings can influence the percentage of people choosing to use the stairs versus elevators is unknown. The purpose of this study was to determine if buildings with centrally located, accessible, and aesthetically pleasing staircases result in a greater percentage of people taking the stairs. Direct observations of stair and elevator use were conducted in 3 buildings on a university campus. One of the buildings had a bank of 4 centrally located elevators and a fire escape stairwell behind a steel door. The other 2 buildings had centrally located staircases and out-of-the-way elevators. The percentage of people who ascended the stairs was 8.1% in the elevator-centric building, compared with 72.8% and 81.1% in the 2 stair-centric buildings (P < .001). In addition, the percentage of people who descended the stairs was 10.8% in the first building, compared with 89.5% and 93.7% in the stair-centric buildings (P < .001). The results of the current study suggest that if buildings are constructed with centrally located, accessible, and aesthetically pleasing staircases, a greater percentage of people will choose to take the stairs.

Do lower-extremity joint dynamics change when stair negotiation is initiated with a self-selected comfortable gait speed?

PubMed

Vallabhajosula, Srikant; Yentes, Jennifer M; Momcilovic, Mira; Blanke, Daniel J; Stergiou, Nicholas

2012-02-01

Previous research on the biomechanics of stair negotiation has ignored the effect of the approaching speed. We examined if initiating stair ascent with a comfortable self-selected speed can affect the lower-extremity joint moments and powers as compared to initiating stair ascent directly in front of the stairs. Healthy young adults ascended a custom-built staircase instrumented with force platforms. Kinematics and kinetics data were collected simultaneously for two conditions: starting from farther away and starting in front of the stairs and analyzed at the first and second ipsilateral steps. Results showed that for the first step, participants produced greater peak knee extensor moment, peak hip extensor and flexor moments and peak hip positive power while starting from farther away. Also, for both the conditions combined, participants generated lesser peak ankle plantiflexor, greater peak knee flexor moment, lesser peak ankle negative power and greater peak hip negative power while encountering the first step. These results identify the importance of the starting position in experiments dealing with biomechanics of stair negotiation. Further, these findings have important implications for studying stair ascent characteristics of other populations such as older adults. Copyright © 2011 Elsevier B.V. All rights reserved.

Assessing psychosocial correlates of parental safety behaviour using Protection Motivation Theory: stair gate presence and use among parents of toddlers.

PubMed

Beirens, T M J; Brug, J; van Beeck, E F; Dekker, R; den Hertog, P; Raat, H

2008-08-01

Unintentional injury due to falls is one of the main reasons for hospitalization among children 0-4 years of age. The goal of this study was to assess the psychosocial correlates of parental safety behaviours to prevent falls from a staircase due to the lack of or the lack of adequate use of a stair gate. Data were collected from a cross-sectional survey using self-administered questionnaires mailed to a population sample of 2470 parents with toddlers. Associations between self-reported habits on the presence and use of stair gates and family and psychosocial factors were analysed, using descriptive statistics and multiple regression models, based on Protection Motivation Theory. The presence of stair gates was associated with family situation, perceived vulnerability, response efficacy, social norms and descriptive norms. The use of stair gates was associated with family situation, response efficacy, self-efficacy and perceived advantages of safe behaviour. The full model explained 32 and 24% of the variance in the presence of stair gates and the use of stair gates, respectively, indicating a large and medium effect size. Programmes promoting the presence and adequate use of stair gates should address the family situation, personal cognitive factors as well as social factors.

Assessing psychosocial correlates of parental safety behaviour using Protection Motivation Theory: stair gate presence and use among parents of toddlers

PubMed Central

Beirens, T. M. J.; Brug, J.; van Beeck, E. F.; Dekker, R.; den Hertog, P.; Raat, H.

2008-01-01

Unintentional injury due to falls is one of the main reasons for hospitalization among children 0–4 years of age. The goal of this study was to assess the psychosocial correlates of parental safety behaviours to prevent falls from a staircase due to the lack of or the lack of adequate use of a stair gate. Data were collected from a cross-sectional survey using self-administered questionnaires mailed to a population sample of 2470 parents with toddlers. Associations between self-reported habits on the presence and use of stair gates and family and psychosocial factors were analysed, using descriptive statistics and multiple regression models, based on Protection Motivation Theory. The presence of stair gates was associated with family situation, perceived vulnerability, response efficacy, social norms and descriptive norms. The use of stair gates was associated with family situation, response efficacy, self-efficacy and perceived advantages of safe behaviour. The full model explained 32 and 24% of the variance in the presence of stair gates and the use of stair gates, respectively, indicating a large and medium effect size. Programmes promoting the presence and adequate use of stair gates should address the family situation, personal cognitive factors as well as social factors. PMID:17947245

Forward stair descent with hybrid neuroprosthesis after paralysis: Single case study demonstrating feasibility

PubMed Central

Bulea, Thomas C.; Kobetic, Rudi; Audu, Musa L.; Schnellenberger, John R.; Pinault, Gilles; Triolo, Ronald J.

2015-01-01

The ability to negotiate stairs is important for community access and independent mobility but requires more effort and strength than level walking. For this reason, previous attempts to utilize functional neuromuscular stimulation (FNS) to restore stair navigation after spinal cord injury (SCI) have had limited success and are not readily generalizable. Stair descent is particularly challenging because it requires energy absorption via eccentric muscle contractions, a task not easily accomplished with FNS. This article presents the design and initial testing of a hybrid neuroprosthesis with a variable impedance knee mechanism (VIKM-HNP) for stair descent. Using a 16-channel percutaneous FNS system, a muscle activation pattern was synthesized to descend stairs with the VIKM-HNP in a step-by-step fashion. A finite state control system was implemented to deactivate knee extensor stimulation and utilize the VIKM-HNP to absorb energy and regulate descent speed. Feasibility testing was performed on one individual with complete thoracic-level SCI. Stair descent was achieved with maximum upper-limb forces of less than 45% body weight compared with previously reported value of 70% with FNS only. The experiments also provided insight into design requirements for future hybrid systems for stair navigation, the implications of which are discussed. PMID:25437932

Volitional control of ankle plantar flexion in a powered transtibial prosthesis during stair-ambulation.

PubMed

Kannape, Oliver A; Herr, Hugh M

2014-01-01

Although great advances have been made in the design and control of lower extremity prostheses, walking on different terrains, such as ramps or stairs, and transitioning between these terrains remains a major challenge for the field. In order to generalize biomimetic behaviour of active lower-limb prostheses top-down volitional control is required but has until recently been deemed unfeasible due to the difficulties involved in acquiring an adequate electromyographic (EMG) signal. In this study, we hypothesize that a transtibial amputee can extend the functionality of a hybrid controller, designed for level ground walking, to stair ascent and descent by volitionally modulating powered plantar-flexion of the prosthesis. We here present data illustrating that the participant is able to reproduce ankle push-off behaviour of the intrinsic controller during stair ascent as well as prevent inadvertent push-off during stair descent. Our findings suggest that EMG signal from the residual limb muscles can be used to transition between level-ground walking and stair ascent/descent within a single step and significantly improve prosthesis performance during stair-ambulation.

Motivational signage increases physical activity on a college campus.

PubMed

Ford, M Allison; Torok, Donald

2008-01-01

The authors evaluated whether motivational signage influenced rates of stair use relative to elevator use on a college campus. In March and April 2004, the authors observed students, faculty, staff, and any visitors accessing a college campus building. During Phase I, the authors monitored ascending stair and elevator use at the same time each weekday (Monday-Friday). During Phase II, the authors placed motivational signs encouraging stair use at the bottom of the stairs and outside and inside the elevators. During the third week (Phase III), the authors removed the signs. The authors observed 18,389 ascending trips during the 3 weeks of the study. Motivational signs significantly contributed to an 18.6% increase in stair use in the second week, which was maintained in the following week. The signage intervention successfully enhanced physical activity on a college campus by providing educational health tips that may have served as motivation to choose the stairs.

Gender differences of sagittal knee and ankle biomechanics during stair-to-ground descent transition.

PubMed

Hong, Yoon No Gregory; Shin, Choongsoo S

2015-12-01

Falls on stairs often result in severe injury and occur twice as frequently in women. However, gender differences in kinetics and kinematics during stair descent are unknown. Thus, this study aimed to determine whether gender differences of knee and ankle biomechanics exist in the sagittal plane during the stair-to-ground descending transition. It was hypothesized that 1) women would reveal higher ground-toe-trochanter angle and lower ground-toe length during stair-to-ground descent transition than men; and 2) women would reveal lower peak knee extension moment during stair-to-ground descent transition than men. Fifteen men and fifteen women were recruited and performed a stair descent activity. Kinetic and kinematic data were obtained using a force plate and motion capture system. The women performed the stair descent with a lower peak knee extension moment and a peak knee power at the early weight acceptance phase. The women also revealed a higher ground-toe-trochanter angle and a lower ground-toe length, which indicated a more forward position of the lower extremity relative to the toe contact point at both the initial contact and at the time of peak kinematic and kinetic events. This study found that knee and ankle kinematics and kinetics differed significantly between the genders due to differences in ground-toe-trochanter angle. Women have a different stair descending strategy that reduces the demand of the lower extremity muscle function, but this strategy seems to increase the risk of falls. Copyright © 2015 Elsevier Ltd. All rights reserved.

Immediate effects of a distal gait modification during stair descent in individuals with patellofemoral pain.

PubMed

Aliberti, Sandra; Mezêncio, Bruno; Amadio, Alberto Carlos; Serrão, Julio Cerca; Mochizuki, Luis

2018-05-23

Knee pain during stair managing is a common complaint among individuals with PFP and can negatively affect their activities of daily living. Gait modification programs can be used to decrease patellofemoral pain. Immediate effects of a stair descent distal gait modification session that intended to emphasize forefoot landing during stair descent are described in this study. To analyze the immediate effects of a distal gait modification session on lower extremity movements and intensity of pain in women with patellofemoral pain during stair descent. Nonrandomized controlled trial. Sixteen women with patellofemoral pain were allocated into two groups: (1) Gait Modification Group (n = 8); and 2) Control Group (n = 8). The intensity of pain (visual analog scale) and kinematics of knee, ankle, and forefoot (multi-segmental foot model) during stair descent were assessed before and after the intervention. After the gait modification session, there was an increase of forefoot eversion and ankle plantarflexion as well as a decrease of knee flexion. An immediate decrease in patellofemoral pain intensity during stair descent was also observed. The distal gait modification session changed the lower extremity kinetic chain strategy of movement, increasing foot and ankle movement contribution and decreasing knee contribution to the task. An immediate decrease in patellofemoral pain intensity during stair descent was also observed. To emphasize forefoot landing may be a useful intervention to immediately relieve pain in patients with patellofemoral pain during stair descent. Clinical studies are needed to verify the gait modification session effects in medium and long terms.

Kinematic analysis of the thoracic limb of healthy dogs during descending stair and ramp exercises.

PubMed

Kopec, Nadia L; Williams, Jane M; Tabor, Gillian F

2018-01-01

OBJECTIVE To compare the kinematics of the thoracic limb of healthy dogs during descent of stairs and a ramp with those during a trot across a flat surface (control). ANIMALS 8 privately owned dogs. PROCEDURES For each dog, the left thoracic limb was instrumented with 5 anatomic markers to facilitate collection of 2-D kinematic data during each of 3 exercises (descending stairs, descending a ramp, and trotting over a flat surface). The stair exercise consisted of 4 steps with a 35° slope. For the ramp exercise, a solid plank was placed over the steps to create a ramp with a 35° slope. For the flat exercise, dogs were trotted across a flat surface for 2 m. Mean peak extension, peak flexion, and range of movement (ROM) of the shoulder, elbow, and carpal joints were compared among the 3 exercises. RESULTS Mean ROM for the shoulder and elbow joints during the stair exercise were significantly greater than during the flat exercise. Mean peak extension of the elbow joint during the flat exercise was significantly greater than that during both the stair and ramp exercises. Mean peak flexion of the elbow joint during the stair exercise was significantly greater than that during the flat exercise. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that descending stairs may be beneficial for increasing the ROM of the shoulder and elbow joints of dogs. Descending stair exercises may increase elbow joint flexion, whereas flat exercises may be better for targeting elbow joint extension.

Does It Really Matter Where You Look When Walking on Stairs? Insights from a Dual-Task Study

PubMed Central

Miyasike-daSilva, Veronica; McIlroy, William E.

2012-01-01

Although the visual system is known to provide relevant information to guide stair locomotion, there is less understanding of the specific contributions of foveal and peripheral visual field information. The present study investigated the specific role of foveal vision during stair locomotion and ground-stairs transitions by using a dual-task paradigm to influence the ability to rely on foveal vision. Fifteen healthy adults (26.9±3.3 years; 8 females) ascended a 7-step staircase under four conditions: no secondary tasks (CONTROL); gaze fixation on a fixed target located at the end of the pathway (TARGET); visual reaction time task (VRT); and auditory reaction time task (ART). Gaze fixations towards stair features were significantly reduced in TARGET and VRT compared to CONTROL and ART. Despite the reduced fixations, participants were able to successfully ascend stairs and rarely used the handrail. Step time was increased during VRT compared to CONTROL in most stair steps. Navigating on the transition steps did not require more gaze fixations than the middle steps. However, reaction time tended to increase during locomotion on transitions suggesting additional executive demands during this phase. These findings suggest that foveal vision may not be an essential source of visual information regarding stair features to guide stair walking, despite the unique control challenges at transition phases as highlighted by phase-specific challenges in dual-tasking. Instead, the tendency to look at the steps in usual conditions likely provides a stable reference frame for extraction of visual information regarding step features from the entire visual field. PMID:22970297

29 CFR 1917.120 - Fixed stairways.

Code of Federal Regulations, 2010 CFR

2010-07-01

... stairs (the angle of which changes with the rise and fall of the base support) or to stairs forming an... nosing shall be straight leading edges. (2) Stair landings shall be at least 20 inches (50.8 cm) in depth...

Fatal falls involving stairs: an anthropological analysis of skeletal trauma.

PubMed

Rowbotham, Samantha K; Blau, Soren; Hislop-Jambrich, Jacqueline; Francis, Victoria

2018-06-01

The skeletal blunt force trauma resulting from fatal falls involving stairs is complex. There are countless ways an individual may fall when stairs are involved, and thus a variety of ways the skeleton may fracture. Therefore anecdotally, it may be said that there is no specific skeletal trauma characteristic of this fall type. In order to scientifically investigate this anecdotal understanding, this study provides a detailed investigation of the skeletal fracture patterns and morphologies resulting from fatal falls involving stairs. Skeletal trauma was analyzed using the full-body postmortem computed tomography scans of 57 individuals who died from a fall involving stairs. Trauma was examined in the context of the variables that potentially influence how an individual falls (i.e. sex, age, body mass index, number of stairs involved, psychoactive drugs, pre-existing conditions, landing surface and manner of the fall) using logistic regression. Skeletal trauma primarily occurred in the axial skeleton. An analysis of fracture patterns showed the cranial base was less likely to fracture in younger individuals and the cervical vertebrae were more likely to fracture in falls that involved more than half a flight of stairs. A total of 56 fracture morphologies were identified. Of these, diastatic fractures were less likely to occur in older individuals. Findings indicate that there are skeletal fracture patterns and morphologies characteristic of a fatal fall involving stairs.

Autonomous motivation is not enough: the role of compensatory health beliefs for the readiness to change stair and elevator use.

PubMed

Radtke, Theda; Rackow, Pamela

2014-11-28

Compensatory health beliefs (CHBs) are beliefs that an unhealthy behavior can be compensated with a healthy behavior. In line with the CHBs model, the aim of this study was twofold. First, the study investigated the relationship between autonomous motivation and CHBs that physical inactivity can be compensated by taking the stairs instead of the elevator. Second, the study focused on the associations between CHBs and readiness to use the stairs more often and stair and elevator use. Thus, a cross-sectional online questionnaire was designed that was filled out by 135 participants. Path analysis showed that individuals with stronger autonomous motivation to use the stairs strongly agreed that sedentary behavior could be compensated by taking the stairs instead of the elevator. Moreover, CHBs were positively related to readiness to change behavior, but not to self-reported stair and elevator use. Even though future research is necessary to replicate these findings, autonomous motivation seems to have a positive impact on CHBs which, in turn, might boost an intended behavior change. Thus, promoting possible compensation of physical inactivity might foster the readiness to change the unhealthy behavior.

Autonomous Motivation Is Not Enough: The Role of Compensatory Health Beliefs for the Readiness to Change Stair and Elevator Use

PubMed Central

Radtke, Theda; Rackow, Pamela

2014-01-01

Compensatory health beliefs (CHBs) are beliefs that an unhealthy behavior can be compensated with a healthy behavior. In line with the CHBs model, the aim of this study was twofold. First, the study investigated the relationship between autonomous motivation and CHBs that physical inactivity can be compensated by taking the stairs instead of the elevator. Second, the study focused on the associations between CHBs and readiness to use the stairs more often and stair and elevator use. Thus, a cross-sectional online questionnaire was designed that was filled out by 135 participants. Path analysis showed that individuals with stronger autonomous motivation to use the stairs strongly agreed that sedentary behavior could be compensated by taking the stairs instead of the elevator. Moreover, CHBs were positively related to readiness to change behavior, but not to self-reported stair and elevator use. Even though future research is necessary to replicate these findings, autonomous motivation seems to have a positive impact on CHBs which, in turn, might boost an intended behavior change. Thus, promoting possible compensation of physical inactivity might foster the readiness to change the unhealthy behavior. PMID:25464134

4. EXTERIOR OF EAST SIDE SHOWING STAIRS TO CATWALK AND ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

4. EXTERIOR OF EAST SIDE SHOWING STAIRS TO CATWALK AND OPEN UTILITY ROOM DOOR. OPEN DOOR AT BOTTOM OF STAIRS LEADS TO BASEMENT. VIEW TO SOUTHWEST. - Big Creek Hydroelectric System, Powerhouse 8, Operator Cottage, Big Creek, Big Creek, Fresno County, CA

INTERIOR VIEW OF SECOND FLOOR STAIR HALL. SHOWING THE IRON ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

INTERIOR VIEW OF SECOND FLOOR STAIR HALL. SHOWING THE IRON STAIR RAILS AND NEWEL POSTS WITH INCISED LINES. NOTE THE TONGUE-AND-GROOVE WOOD FLOORING. VIEW FACING EAST. - Hickam Field, Officers' Housing Type L, 702 Julian Avenue, Honolulu, Honolulu County, HI

Biomechanics of the Ankle-Foot System during Stair Ambulation: Implications for Design of Advanced Ankle-Foot Prostheses

DTIC Science & Technology

2011-12-15

Biomechanics of the ankle–foot system during stair ambulation: Implications for design of advanced ankle–foot prostheses$ Emily H. Sinitski a, Andrew...Wilken). Please cite this article as: Sinitski, E.H., et al., Biomechanics of the ankle–foot system during stair ambulation: Implications for design of...REPORT TYPE 3. DATES COVERED 00-00-2011 to 00-00-2011 4. TITLE AND SUBTITLE Biomechanics Of The Ankle-Foot System During Stair Ambulation

Robotics Systems Joint Project Office (RSJPO) Interoperability Profiles (IOPS) 101

DTIC Science & Technology

2012-07-01

interoperability, although they are supported by some interoperability attributes  For example, stair climbing » Stair climbing is not something that...IOPs need to specify » However, the mobility & actuation related interoperable messages can be used to provide stair climbing » Also...interoperability can enable management of different poses or modes, one of which may be stair climbing R O B O T IC S Y S T E M S J P O L e a d e r s h i p

Development of Minimum Physical Fitness Standards for the Canadian Armed Forces. Phase 3

DTIC Science & Technology

1988-03-01

while mounting stairs more than tripled their energy expenditures . Similarly, Astrand and Rodahl (1977) determined that continuous stair climbing...evacuation tasks were restructured to be one-person tasks (i.e., wheels on the land stretcher; a push-skid for the sea evacuation stairs stretcher). Other...kg stoker stretcher 12.5 m to the base of a flight of stairs . The subject then pushed a skid carrying one subject’s share of the mass up and down a

Single-leg squats identify independent stair negotiation ability in older adults referred for a physiotherapy mobility assessment at a rural hospital.

PubMed

Hockings, Rowena L; Schmidt, David D; Cheung, Christopher W

2013-07-01

To determine whether single-leg squats identify ability to negotiate stairs in older adults at a rural hospital. Cross-sectional analytical study. Acute wards and emergency department of a rural hospital in Australia. A systematic sample of 143 older adults (72 men, 71 women, 80.0 ± 6.8 years) from the emergency department or acute wards of Shoalhaven Hospital referred for a physiotherapy mobility assessment. Ability to complete up to three single-leg squats and negotiate up to three steps were measured. Covariates and demographic variables were collected. The squat test had 86% sensitivity, 100% specificity, 100% positive predictive value, and 49% negative predictive value in correctly identifying stair negotiation ability. Participants who could complete single-leg squats were 57 times more likely to be able to independently negotiate stairs than participants who could not complete squats. Multivariate regression analysis indicated that walker use, pain severity and whether participants lived alone were significant and independent predictors of ability to negotiate stairs independently. Single-leg squats may be an accurate identifier of stair negotiation ability in older adults admitted to the hospital for an acute illness or injury. A traditional stairs assessment would be required if older adults were unable to complete the squat test or had moderate to severe pain, used a walker to ambulate, or did not live alone. The squat test is a potentially more-efficient assessment tool than traditional stair assessments in determining an individual's ability to negotiate stairs and suitability for discharge where poor mobility is a problem. © 2013, Copyright the Authors Journal compilation © 2013, The American Geriatrics Society.

Aging may negatively impact movement smoothness during stair negotiation.

PubMed

Dixon, P C; Stirling, L; Xu, X; Chang, C C; Dennerlein, J T; Schiffman, J M

2018-05-26

Stairs represent a barrier to safe locomotion for some older adults, potentially leading to the adoption of a cautious gait strategy that may lack fluidity. This strategy may be characterized as unsmooth; however, stair negotiation smoothness has yet to be quantified. The aims of this study were to assess age- and task-related differences in head and body center of mass (COM) acceleration patterns and smoothness during stair negotiation and to determine if smoothness was associated with the timed "Up and Go" (TUG) test of functional movement. Motion data from nineteen older and twenty young adults performing stair ascent, stair descent, and overground straight walking trials were analyzed and used to compute smoothness based on the log-normalized dimensionless jerk (LDJ) and the velocity spectral arc length (SPARC) metrics. The associations between TUG and smoothness measures were evaluated using Pearson's correlation coefficient (r). Stair tasks increased head and body COM acceleration pattern differences across groups, compared to walking (p < 0.05). LDJ smoothness for the head and body COM decreased in older adults during stair descent, compared to young adults (p ≤ 0.015) and worsened with increasing TUG for all tasks (-0.60 ≤ r ≤ -0.43). SPARC smoothness of the head and body COM increased in older adults, regardless of task (p < 0.001), while correlations showed improved SPARC smoothness with increasing TUG for some tasks (0.33 ≤ r ≤ 0.40). The LDJ outperforms SPARC in identifying age-related stair negotiation adaptations and is associated with performance on a clinical test of gait. Copyright © 2018 Elsevier B.V. All rights reserved.

Northwester upstairs room of northwest wing looking southeast through stair ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Northwester upstairs room of northwest wing looking southeast through stair landing and hallway to southeast room. note far floorboard with smoke damage between historic joists; modern joists in stair landing. - Scheetz Farm, House, 7161 Camp Hill Road, Fort Washington, Montgomery County, PA

Whole-body angular momentum during stair ascent and descent.

PubMed

Silverman, Anne K; Neptune, Richard R; Sinitski, Emily H; Wilken, Jason M

2014-04-01

The generation of whole-body angular momentum is essential in many locomotor tasks and must be regulated in order to maintain dynamic balance. However, angular momentum has not been investigated during stair walking, which is an activity that presents a biomechanical challenge for balance-impaired populations. We investigated three-dimensional whole-body angular momentum during stair ascent and descent and compared it to level walking. Three-dimensional body-segment kinematic and ground reaction force (GRF) data were collected from 30 healthy subjects. Angular momentum was calculated using a 13-segment whole-body model. GRFs, external moment arms and net joint moments were used to interpret the angular momentum results. The range of frontal plane angular momentum was greater for stair ascent relative to level walking. In the transverse and sagittal planes, the range of angular momentum was smaller in stair ascent and descent relative to level walking. Significant differences were also found in the ground reaction forces, external moment arms and net joint moments. The sagittal plane angular momentum results suggest that individuals alter angular momentum to effectively counteract potential trips during stair ascent, and reduce the range of angular momentum to avoid falling forward during stair descent. Further, significant differences in joint moments suggest potential neuromuscular mechanisms that account for the differences in angular momentum between walking conditions. These results provide a baseline for comparison to impaired populations that have difficulty maintaining dynamic balance, particularly during stair ascent and descent. Copyright © 2014 Elsevier B.V. All rights reserved.

Difference in knee rotation between total and unicompartmental knee arthroplasties during stair climbing.

PubMed

Jung, Myung-Chul; Chung, Jun Young; Son, Kwang-Hyun; Wang, Hui; Hwang, Jaejin; Kim, Jay Joong; Kim, Joon Ho; Min, Byoung-Hyun

2014-08-01

The purpose of this study was to compare knee kinematics during stair walking in patients with simultaneous total knee arthroplasty (TKA) and unicompartmental knee arthroplasties (UKA). It was hypothesized that UKA would reproduce more normalized knee kinematics than TKA during stair ascent and descent. Six patients who received UKA in one knee and TKA in the other knee were included in the study. For this study, a four-step staircase was assembled with two force platforms being positioned at the centre of the second and third steps. Each patient was attached with 16 reflective markers at both lower extremities and was asked to perform five roundtrip trials of stair climbing. Kinematic parameters including stance duration, knee angle, vertical ground reaction force (GRF), joint reaction force, and moments were obtained and analysed using a10-camera motion system (VICON, Oxford, UK). Nonparametric Friedman test was used to compare the results between two arthroplasty methods and between stair ascent and descent. Compared to TKA, UKA knees exhibited significantly greater degree of rotation in transverse planes (5.0 degrees during ascent and 6.0 degrees during descent on average), but showed no difference in terms of the other parameters. When comparing the results during stair ascent with descent, overall greater knee angle, vertical GRF, joint reaction force, and moment were observed during stair descent. Both UKA and TKA knees have shown overall similar knee kinematics, though UKA knee may allow greater degree of rotation freedom, which resembles normal knee kinematics during stair walking.

Boosting workplace stair utilization: a study of incremental reinforcement.

PubMed

Schumacher, Joseph E; Utley, Janice; Sutton, Lindsay; Horton, Trudi; Hamer, Trey; You, Zhiying; Klapow, Joshua C

2013-02-01

This study was designed to determine whether engagement in stair taking can be increased in a worksite setting through the provision of an employer-sponsored, behavior-based incentive system in which employees (members) accumulate points that can be redeemed for merchandise. ChipRewards implemented stair utilization in one employer as a part of a larger health incentive engagement program. Using an AB (baseline-intervention) design, members (N = 216) were observed for 6 months (6.17.10 to 12.14.10 or 129 weekdays after excluding 52 weekend days) before the intervention (baseline) and after 6 months (1.1.11 to 6.30.11 with the same number of weekdays) of implementation. Members were 84% female, 51% Caucasian, 48% African American, 3% Hispanic, and 45 years average age. The number of total stair transactions for all members for all days monitored increased from 5,070 to 38,900, and the average number of stair transactions per day rose from 39 to 301, representing over a 600% increase. The overall cost of incentives for stair utilization was $3,739.30 or $17.55 per member on average. This study supports that stair usage in the workplace is a viable way to increase physical activity. This study adds to existing research that attempted to increase stair utilization through promotion only by adding a behavioral reinforcement strategy. Finally, this study demonstrates that a physical activity among employees at the worksite can be increased with minimal relative cost.

29 CFR 1910.24 - Fixed industrial stairs.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 29 Labor 5 2012-07-01 2012-07-01 false Fixed industrial stairs. 1910.24 Section 1910.24 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR OCCUPATIONAL SAFETY AND HEALTH STANDARDS Walking-Working Surfaces § 1910.24 Fixed industrial stairs. (a...

21 CFR 890.3890 - Stair-climbing wheelchair.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Stair-climbing wheelchair. 890.3890 Section 890.3890 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3890 Stair-climbing...

21 CFR 890.3890 - Stair-climbing wheelchair.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Stair-climbing wheelchair. 890.3890 Section 890.3890 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3890 Stair-climbing...

21 CFR 890.3890 - Stair-climbing wheelchair.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Stair-climbing wheelchair. 890.3890 Section 890.3890 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3890 Stair-climbing...

21 CFR 890.3890 - Stair-climbing wheelchair.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Stair-climbing wheelchair. 890.3890 Section 890.3890 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3890 Stair-climbing...

21 CFR 890.3890 - Stair-climbing wheelchair.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Stair-climbing wheelchair. 890.3890 Section 890.3890 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3890 Stair-climbing...

Take Steps Toward a Healthier Life | Poster

Cancer.gov

The National Institutes of Health (NIH) is promoting wellness by encouraging individuals to take the stairs. In an effort to increase participation in this program, NIH has teamed up with Occupational Health Services (OHS). OHS is placing NIH-sponsored “Take the Stairs” stickers on stair entrances, stair exits, and elevators.

29 CFR 1910.24 - Fixed industrial stairs.

Code of Federal Regulations, 2011 CFR

2011-07-01

... machinery, tanks, and other equipment, and stairs leading to or from floors, platforms, or pits. This..., the angle of which changes with the rise and fall of the base support. (b) Where fixed stairs are... providing the leading edge can be readily identified by personnel descending the stairway and provided the...

12. Battery Richmond, emplacement no. 1, iron stair from terreplein ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

12. Battery Richmond, emplacement no. 1, iron stair from terreplein up to loading platform. Beneath stair is doorway to powder room, at left is an entrance to the shot gallery; at center is entance to guard room - Forth Wadsworth Battery Richmond, Fort Wadsworth, Staten Island, New York County, NY

Evaluation and modification of exercise patterns in the natural environment.

PubMed

Brownell, K D; Stunkard, A J; Albaum, J M

1980-12-01

Using a new experimental paradigm to evaluate physical activity in the natural environment, the authors made of 45,694 observations of persons using stairs or an adjacent escalator at a shopping mall, train station, and bus terminal. In study 1, stair use more than doubled for both obese and nonobese persons during two-week periods when a colorful sign encouraging use of the stairs was positioned at the stairs/escalator choice point. In study 2, stair use remained elevated for 15 consecutive days while the sign was present, decreased during a 1-month follow-up period, and returned to baseline by 3 months. These results not only demonstrate the usefulness of this paradigm, but also suggest the strength of simple, inexpensive public health interventions to increase physical activity.

Musical Stairs: A motivational therapy tool for children with disabilities featuring automated detection of stair-climbing gait events via inertial sensors.

PubMed

Khan, Ajmal; Biddiss, Elaine

2017-02-01

Stair-climbing is a key component of rehabilitation therapies for children with physical disabilities. This paper reports on the design of a system, Musical Stairs, to provide auditory feedback during stair-climbing therapies. Musical Stairs is composed of two foot-mounted inertial sensors, a step detection algorithm, and an auditory feedback response. In Phase 1, we establish its clinical feasibility via a Wizard-of-Oz AB/BA cross-over design with 17 children, aged 4-6 years, having diverse diagnoses and gait abilities. Self-, therapist- and blinded-observer reports indicated increased motivation with auditory feedback. Phase 2 describes the construction of a database comprised of synchronized video and inertial data associated with 1568 steps up and down stairs completed by 26 children aged 4-6 years with diverse diagnoses and gait. Lastly, in Phase 3, data from 18 children in the database were used to train a rule-based step detection algorithm based on local minima in the acceleration profile and the foot's swing angle. A step detection rate of 96% [SD=3%] and false positive rate of 6% [SD=5%] were achieved with an independent test set (n=8). Recommendations for future development and evaluation are discussed. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.

The use of point-of-decision prompts to increase stair climbing in Singapore.

PubMed

Sloan, Robert Alan; Haaland, Benjamin Adam; Leung, Carol; Müller-Riemenschneider, Falk

2013-01-07

Physical inactivity is a significant contributor to worldwide mortality and morbidity associated with non-communicable diseases. An excellent avenue to incorporate lifestyle physical activity into regular routine is to encourage the use of stairs during daily commutes. We evaluated the effectiveness of point-of-decision prompts (PODPs) in promoting the use of stairs instead of the escalators in a Singapore Mass Rapid Transit (MRT) station. We measured the number of stair climbers before the PODPs were put up, during the 4 weeks that they were in use, and 2 weeks after they were removed. Measurements at a no intervention control site were additionally taken. The use of stair-riser banners was associated with an increase in the number of people using the stairs by a factor of 1.49 (95% CI 1.34-1.64). After the banners were removed, the number of stair climbers at the experimental station dropped to slightly below baseline levels. The Singapore MRT serves a diverse multi-ethnic population with an average daily ridership of over 2 million and 88 stations island-wide. An increase of physical activity among these MRT commuters would have a large impact at the population level. Our findings can be translated into part of the national strategy to encourage an active lifestyle in Singaporeans.

The Use of Point-of-Decision Prompts to Increase Stair Climbing in Singapore

PubMed Central

Sloan, Robert Alan; Haaland, Benjamin Adam; Leung, Carol; Müller-Riemenschneider, Falk

2013-01-01

Physical inactivity is a significant contributor to worldwide mortality and morbidity associated with non-communicable diseases. An excellent avenue to incorporate lifestyle physical activity into regular routine is to encourage the use of stairs during daily commutes. We evaluated the effectiveness of point-of-decision prompts (PODPs) in promoting the use of stairs instead of the escalators in a Singapore Mass Rapid Transit (MRT) station. We measured the number of stair climbers before the PODPs were put up, during the 4 weeks that they were in use, and 2 weeks after they were removed. Measurements at a no intervention control site were additionally taken. The use of stair-riser banners was associated with an increase in the number of people using the stairs by a factor of 1.49 (95% CI 1.34–1.64). After the banners were removed, the number of stair climbers at the experimental station dropped to slightly below baseline levels. The Singapore MRT serves a diverse multi-ethnic population with an average daily ridership of over 2 million and 88 stations island-wide. An increase of physical activity among these MRT commuters would have a large impact at the population level. Our findings can be translated into part of the national strategy to encourage an active lifestyle in Singaporeans. PMID:23296208

Influence of restricted vision and knee joint range of motion on gait properties during level walking and stair ascent and descent.

PubMed

Demura, Tomohiro; Demura, Shin-ich

2011-01-01

Because elderly individuals experience marked declines in various physical functions (e.g., vision, joint function) simultaneously, it is difficult to clarify the individual effects of these functional declines on walking. However, by imposing vision and joint function restrictions on young men, the effects of these functional declines on walking can be clarified. The authors aimed to determine the effect of restricted vision and range of motion (ROM) of the knee joint on gait properties while walking and ascending or descending stairs. Fifteen healthy young adults performed level walking and stair ascent and descent during control, vision restriction, and knee joint ROM restriction conditions. During level walking, walking speed and step width decreased, and double support time increased significantly with vision and knee joint ROM restrictions. Stance time, step width, and walking angle increased only with knee joint ROM restriction. Stance time, swing time, and double support time were significantly longer in level walking, stair descent, and stair ascent, in that order. The effects of vision and knee joint ROM restrictions were significantly larger than the control conditions. In conclusion, vision and knee joint ROM restrictions affect gait during level walking and stair ascent and descent. This effect is marked in stair ascent with knee joint ROM restriction.

Carrying asymmetric loads during stair negotiation.

PubMed

Wang, Junsig; Gillette, Jason

2017-03-01

Individuals often carry items in one hand instead of both hands during activities of daily living. The combined effects of carrying asymmetric loads and stair negotiation may create even higher demands on the low back and lower extremity. The purpose of this study was to investigate the effect of symmetric and asymmetric loading conditions on L5/S1 and lower extremity moments during stair negotiation. Twenty-two college students performed stair ascent and stair descent on a three-step staircase (step height 18.5cm, tread depth 29.5cm) at preferred pace under five load conditions: no load, 10% body weight (BW) unilateral load, 20% BW unilateral load, 10% BW bilateral load, and 20% BW bilateral load. Video cameras and force platforms were used to collect kinematic and kinetic data. Inverse dynamics was used to calculate frontal plane moments for the L5/S1 and lower extremity. A 20% BW unilateral load resulted in significantly higher peak L5/S1 lateral bending, hip abduction, and external knee varus moments than nearly all other loading conditions during stair ascent and stair descent. Therefore, we suggest potential benefits when carrying symmetrical loads as compared to an asymmetric load in order to decrease the frontal joint moments, particularly at 20% BW load. Copyright © 2017 Elsevier B.V. All rights reserved.

Ascending and Descending in Virtual Reality: Simple and Safe System Using Passive Haptics.

PubMed

Nagao, Ryohei; Matsumoto, Keigo; Narumi, Takuji; Tanikawa, Tomohiro; Hirose, Michitaka

2018-04-01

This paper presents a novel interactive system that provides users with virtual reality (VR) experiences, wherein users feel as if they are ascending/descending stairs through passive haptic feedback. The passive haptic stimuli are provided by small bumps under the feet of users; these stimuli are provided to represent the edges of the stairs in the virtual environment. The visual stimuli of the stairs and shoes, provided by head-mounted displays, evoke a visuo-haptic interaction that modifies a user's perception of the floor shape. Our system enables users to experience all types of stairs, such as half-turn and spiral stairs, in a VR setting. We conducted a preliminary user study and two experiments to evaluate the proposed technique. The preliminary user study investigated the effectiveness of the basic idea associated with the proposed technique for the case of a user ascending stairs. The results demonstrated that the passive haptic feedback produced by the small bumps enhanced the user's feeling of presence and sense of ascending. We subsequently performed an experiment to investigate an improved viewpoint manipulation method and the interaction of the manipulation and haptics for both the ascending and descending cases. The experimental results demonstrated that the participants had a feeling of presence and felt a steep stair gradient under the condition of haptic feedback and viewpoint manipulation based on the characteristics of actual stair walking data. However, these results also indicated that the proposed system may not be as effective in providing a sense of descending stairs without an optimization of the haptic stimuli. We then redesigned the shape of the small bumps, and evaluated the design in a second experiment. The results indicated that the best shape to present haptic stimuli is a right triangle cross section in both the ascending and descending cases. Although it is necessary to install small protrusions in the determined direction, by using this optimized shape the users feeling of presence of the stairs and the sensation of walking up and down was enhanced.

Influence of non-level walking on pedometer accuracy.

PubMed

Leicht, Anthony S; Crowther, Robert G

2009-05-01

The YAMAX Digiwalker pedometer has been previously confirmed as a valid and reliable monitor during level walking, however, little is known about its accuracy during non-level walking activities or between genders. Subsequently, this study examined the influence of non-level walking and gender on pedometer accuracy. Forty-six healthy adults completed 3-min bouts of treadmill walking at their normal walking pace during 11 inclines (0-10%) while another 123 healthy adults completed walking up and down 47 stairs. During walking, participants wore a YAMAX Digiwalker SW-700 pedometer with the number of steps taken and registered by the pedometer recorded. Pedometer difference (steps registered-steps taken), net error (% of steps taken), absolute error (absolute % of steps taken) and gender were examined by repeated measures two-way ANOVA and Tukey's post hoc tests. During incline walking, pedometer accuracy indices were similar between inclines and gender except for a significantly greater step difference (-7+/-5 steps vs. 1+/-4 steps) and net error (-2.4+/-1.8% for 9% vs. 0.4+/-1.2% for 2%). Step difference and net error were significantly greater during stair descent compared to stair ascent while absolute error was significantly greater during stair ascent compared to stair descent. The current study demonstrated that the YAMAX Digiwalker SW-700 pedometer exhibited good accuracy during incline walking up to 10% while it overestimated steps taken during stair ascent/descent with greater overestimation during stair descent. Stair walking activity should be documented in field studies as the YAMAX Digiwalker SW-700 pedometer overestimates this activity type.

Differences Between Gait on Stairs and Flat Surfaces in Relation to Fall Risk and Future Falls.

PubMed

Wang, Kejia; Delbaere, Kim; Brodie, Matthew A D; Lovell, Nigel H; Kark, Lauren; Lord, Stephen R; Redmond, Stephen J

2017-11-01

We used body-worn inertial sensors to quantify differences in semi-free-living gait between stairs and on normal flat ground in older adults, and investigated the utility of assessing gait on these terrains for predicting the occurrence of multiple falls. Eighty-two community-dwelling older adults wore two inertial sensors, on the lower back and the right ankle, during several bouts of walking on flat surfaces and up and down stairs, in between rests and activities of daily living. Derived from the vertical acceleration at the lower back, step rate was calculated from the signal's fundamental frequency. Step rate variability was the width of this fundamental frequency peak from the signal's power spectral density. Movement vigor was calculated at both body locations from the signal variance. Partial Spearman correlations between gait parameters and physiological fall risk factors (components from the Physiological Profile Assessment) were calculated while controlling for age and gender. Overall, anteroposterior vigor at the lower back in stair descent was lower in subjects with longer reaction times. Older adults walked more slowly on stairs, but they were not significantly slower on flat surfaces. Using logistic regression, faster step rate in stair descent was associated with multiple prospective falls over 12 months. No significant associations were shown from gait parameters derived during walking upstairs or on flat surfaces. These results suggest that stair descent gait may provide more insight into fall risk than regular walking and stair ascent, and that further sensor-based investigation into unsupervised gait on different terrains would be valuable.

49 CFR 214.519 - Floors, decks, stairs, and ladders of on-track roadway maintenance machines.

Code of Federal Regulations, 2010 CFR

2010-10-01

... roadway maintenance machines. 214.519 Section 214.519 Transportation Other Regulations Relating to... SAFETY On-Track Roadway Maintenance Machines and Hi-Rail Vehicles § 214.519 Floors, decks, stairs, and ladders of on-track roadway maintenance machines. Floors, decks, stairs, and ladders of on-track roadway...

49 CFR 214.519 - Floors, decks, stairs, and ladders of on-track roadway maintenance machines.

Code of Federal Regulations, 2011 CFR

2011-10-01

... roadway maintenance machines. 214.519 Section 214.519 Transportation Other Regulations Relating to... SAFETY On-Track Roadway Maintenance Machines and Hi-Rail Vehicles § 214.519 Floors, decks, stairs, and ladders of on-track roadway maintenance machines. Floors, decks, stairs, and ladders of on-track roadway...

Stairs or escalator? Using theories of persuasion and motivation to facilitate healthy decision making.

PubMed

Suri, Gaurav; Sheppes, Gal; Leslie, Sara; Gross, James J

2014-12-01

To encourage an increase in daily activity, researchers have tried a variety of health-related communications, but with mixed results. In the present research-using the stair escalator choice context-we examined predictions derived from the Heuristic Systematic Model (HSM), Self Determination Theory (SDT), and related theories. Specifically, we tested whether (as predicted by HSM) signs that encourage heuristic processing ("Take the Stairs") would have greatest impact when placed at the stair/escalator point of choice (when processing time is limited), whereas signs that encourage systematic processing ("Will You Take the Stairs?") would have greatest impact when placed at some distance from the point of choice (when processing time is less limited). We also tested whether (as predicted by SDT) messages promoting autonomy would be more likely to result in sustained motivated behavior (i.e., stair taking at subsequent uncued choice points) than messages that use commands. A series of studies involving more than 9,000 pedestrians provided support for these predictions. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

Increased Difficulties in Managing Stairs in Visually Impaired Older Adults: A Community-Based Survey.

PubMed

Pan, Chen-Wei; Liu, Hu; Sun, Hong-Peng; Xu, Yong

2015-01-01

Managing stairs is a challenging aspect of daily activities of living for older people. We assessed whether older adults with visual impairment (VI) have greater difficulties of managing stairs in daily lives. The study was designed as a community-based cross-sectional study based on a Chinese cohort aged 60 years and older in rural China. Visual acuity (VA) was measured in both eyes using a retro-illuminated Snellen chart with tumbling-E optotypes. VI (including blindness) was defined as presenting VA of worse than 20/60 in either eye. Having any difficulties in managing stairs was self-reported based on a question drawn from the Barthel Index. Information on participants' socioeconomic status, lifestyle-related factors, diseases histories and medication intake was collected using a questionnaire. The Barthel Index, Activities of Daily Living questionnaire was completed by 4597 (99.7%) participants including 2218 men and 2379 women. The age of the participants ranged from 60 to 93 years with a mean of 67.6 ± 6.3 years. In age and gender adjusted models, adults with VI had a higher likelihood of having difficulties in managing stairs (odds ratio [OR] = 2.7; 95% confidence interval [CI] 2.0, 3.7) compared with those without. The association of VI with the likelihood of having difficulties in managing stairs was stronger in older adults who lived alone (OR = 3.2; 95%CI 1.8, 4.5) compared with those who lived with other family members (OR = 2.0; 95%CI 1.3, 4.3). Compared with hypertension, diabetes, obesity and cognitive dysfunction, VI had the greatest impact on people's abilities of managing stairs. VI was associated with an increased likelihood of having difficulties in managing stairs, especially in those who lived alone. However, whether the finding could be extrapolated to other populations warrants further studies as different environmental exposures such as illumination and types of stairs may alter the association observed in this study.

A simple health sign increases stair use in a shopping mall and two train stations in Flanders, Belgium.

PubMed

Boen, Filip; Maurissen, Katrien; Opdenacker, Joke

2010-06-01

The aim of this study was to test the impact of a simple health-promotion sign on stair use in three community settings in Flanders, Belgium. A health sign was placed at the junction between the stairs and an escalator in a shopping mall and two train stations. Observations took place on four days: baseline, first intervention, post-intervention and second intervention. In the second station, a second post-intervention phase was added. In total, 1437 choices of shoppers were registered in the mall, while 2869 and 2025 choices of commuters were recorded in the two stations, respectively. Despite the different baselines of stair use, the introduction of the health sign in the first intervention phase resulted in a significant increase in all three settings: 10.0% increase in the mall, 8.6% in the first station and 18.0% in the second station. In the second station, the increase during the second intervention exceeded that of the first intervention. Moreover, in this station stair use in the second post-intervention phase was significantly higher than at baseline. An inexpensive health-promoting sign has a substantial effect on the proportion of stair users among shoppers and commuters. Preliminary evidence was found that repeated exposure to a health sign might have a longer term effect on stair use.

Do Simple Warning Signs Enhance the Use of Stairs?

ERIC Educational Resources Information Center

Aksay, Ebubekir

2014-01-01

Objective: The aim of this study was to investigate the use of stairways/moving stairways in shopping malls and examine the extent to which simple warning signs determined whether people took the stairs. Design: Large posters that could readily be seen by mall visitors were situated between the stairs and moving stairways in shopping malls.…

29 CFR 1917.120 - Fixed stairways.

Code of Federal Regulations, 2011 CFR

2011-07-01

... be positioned within the range of 30 degrees to 50 degrees to the horizontal with uniform riser.... Riser height shall be from 6 to 7.5 inches (15.24 to 19.05 cm), stair width a minimum of 22 inches (55... stairs having four or more risers shall have stair railings or handrails complying with § 1917.112(c)(1...

29 CFR 1917.120 - Fixed stairways.

Code of Federal Regulations, 2013 CFR

2013-07-01

... be positioned within the range of 30 degrees to 50 degrees to the horizontal with uniform riser.... Riser height shall be from 6 to 7.5 inches (15.24 to 19.05 cm), stair width a minimum of 22 inches (55... stairs having four or more risers shall have stair railings or handrails complying with § 1917.112(c)(1...

29 CFR 1917.120 - Fixed stairways.

Code of Federal Regulations, 2012 CFR

2012-07-01

... be positioned within the range of 30 degrees to 50 degrees to the horizontal with uniform riser.... Riser height shall be from 6 to 7.5 inches (15.24 to 19.05 cm), stair width a minimum of 22 inches (55... stairs having four or more risers shall have stair railings or handrails complying with § 1917.112(c)(1...

29 CFR 1917.120 - Fixed stairways.

Code of Federal Regulations, 2014 CFR

2014-07-01

... be positioned within the range of 30 degrees to 50 degrees to the horizontal with uniform riser.... Riser height shall be from 6 to 7.5 inches (15.24 to 19.05 cm), stair width a minimum of 22 inches (55... stairs having four or more risers shall have stair railings or handrails complying with § 1917.112(c)(1...

Clomiphene citrate 'stair-step' protocol vs. traditional protocol in patients with polycystic ovary syndrome: a randomized controlled trial.

PubMed

Deveci, Canan Dura; Demir, Berfu; Sengul, Ozlem; Dilbaz, Berna; Goktolga, Umit

2015-01-01

To evaluate the efficacy of the stair-step protocol using clomiphene citrate (CC) and to assess the uterine and systemic side effects in patients with polycystic ovary syndrome (PCOS). A total of 60 PCOS patients who failed to respond to 50 mg/day for 5 days of CC treatment within the cycle were randomly allocated to the control (traditional protocol) and study (stair-step protocol) groups. In the stair-step protocol,patients were treated with CC 50 mg/day for 5 days and then in nonresponsive patients, the dosage was increased to 100 mg/day for 5 days in the same cycle. Patients who failed the 50 mg/day CC treatment in the previous cycle were stimulated with 100 mg/day CC and were accepted as the control group. Ovulation and pregnancy rates, duration of treatment and uterine and systemic side effects were evaluated. Ovulation and pregnancy rates were similar between the stair-step and the control group (43.3 vs. 33.3 %, respectively) (16.7 vs. 10 %, respectively). The duration of treatment was significantly shorter in stair-step compared to traditional protocol (20.5 ± 2.0 vs. 48.6 ± 2.4 days, respectively). There were no significant differences in the systemic side effects between the groups. Uterine side effects were evaluated with endometrial thickness and uterine artery Doppler ultrasound; no significant differences were observed in stair-step compared to traditional protocol. The stair-step protocol was determined to have a significantly shorter treatment period without any detrimental effect on the ovulation and pregnancy rates.

Crossover study of amputee stair ascent and descent biomechanics using Genium and C-Leg prostheses with comparison to non-amputee control.

PubMed

Lura, Derek J; Wernke, Matthew W; Carey, Stephanie L; Kahle, Jason T; Miro, Rebecca M; Highsmith, M Jason

2017-10-01

This study was a randomized crossover of stair ambulation of Transfemoral Amputees (TFAs) using the Genium and C-Leg prosthetic knees. TFAs typically have difficulty ascending and descending stairs, limiting community mobility. The objective of this study was to determine the relative efficacy of the Genium and C-Leg prostheses for stair ascent and descent, and their absolute efficacy relative to non-amputees. Twenty TFAs, and five non-amputees participated in the study. TFAs were randomized to begin the study with the Genium or C-Leg prosthesis. Informed consent was obtained from all participants prior to data collection and the study was listed on clinicaltrials.gov (#NCT01473662). After fitting, accommodation, and training, participants were asked to demonstrate their preferred gait pattern for stair ascent and descent and a step-over-step pattern if able. TFAs then switched prosthetic legs and repeated fitting, accommodation, training, and testing. An eight camera Vicon optical motion analysis system, and two AMTI force plates were used to track and analyze the participants' gait patterns, knee flexion angles, knee moment normalized by body weight, and swing time. For stair descent, no significant differences were found between prostheses. For stair ascent, Genium use resulted in: increased ability to use a step-over-step gait pattern (p=0.03), increased prosthetic side peak knee flexion (p<0.01), and increased swing duration (p<0.01). Changes in contralateral side outcomes and in knee moment were not significant. Overall the Genium knee decreased deficiency in gait patterns for stair ascent relative to the C-Leg, by enabling gait patterns that more closely resembled non-amputees. Copyright © 2017 Elsevier B.V. All rights reserved.

Innovative gait robot for the repetitive practice of floor walking and stair climbing up and down in stroke patients

PubMed Central

2010-01-01

Background Stair climbing up and down is an essential part of everyday's mobility. To enable wheelchair-dependent patients the repetitive practice of this task, a novel gait robot, G-EO-Systems (EO, Lat: I walk), based on the end-effector principle, has been designed. The trajectories of the foot plates are freely programmable enabling not only the practice of simulated floor walking but also stair climbing up and down. The article intended to compare lower limb muscle activation patterns of hemiparetic subjects during real floor walking and stairs climbing up, and during the corresponding simulated conditions on the machine, and secondly to demonstrate gait improvement on single case after training on the machine. Methods The muscle activation pattern of seven lower limb muscles of six hemiparetic patients during free and simulated walking on the floor and stair climbing was measured via dynamic electromyography. A non-ambulatory, sub-acute stroke patient additionally trained on the G-EO-Systems every workday for five weeks. Results The muscle activation patterns were comparable during the real and simulated conditions, both on the floor and during stair climbing up. Minor differences, concerning the real and simulated floor walking conditions, were a delayed (prolonged) onset (duration) of the thigh muscle activation on the machine across all subjects. Concerning stair climbing conditions, the shank muscle activation was more phasic and timely correct in selected patients on the device. The severely affected subject regained walking and stair climbing ability. Conclusions The G-EO-Systems is an interesting new option in gait rehabilitation after stroke. The lower limb muscle activation patterns were comparable, a training thus feasible, and the positive case report warrants further clinical studies. PMID:20584307

Innovative gait robot for the repetitive practice of floor walking and stair climbing up and down in stroke patients.

PubMed

Hesse, Stefan; Waldner, Andreas; Tomelleri, Christopher

2010-06-28

Stair climbing up and down is an essential part of everyday's mobility. To enable wheelchair-dependent patients the repetitive practice of this task, a novel gait robot, G-EO-Systems (EO, Lat: I walk), based on the end-effector principle, has been designed. The trajectories of the foot plates are freely programmable enabling not only the practice of simulated floor walking but also stair climbing up and down. The article intended to compare lower limb muscle activation patterns of hemiparetic subjects during real floor walking and stairs climbing up, and during the corresponding simulated conditions on the machine, and secondly to demonstrate gait improvement on single case after training on the machine. The muscle activation pattern of seven lower limb muscles of six hemiparetic patients during free and simulated walking on the floor and stair climbing was measured via dynamic electromyography. A non-ambulatory, sub-acute stroke patient additionally trained on the G-EO-Systems every workday for five weeks. The muscle activation patterns were comparable during the real and simulated conditions, both on the floor and during stair climbing up. Minor differences, concerning the real and simulated floor walking conditions, were a delayed (prolonged) onset (duration) of the thigh muscle activation on the machine across all subjects. Concerning stair climbing conditions, the shank muscle activation was more phasic and timely correct in selected patients on the device. The severely affected subject regained walking and stair climbing ability. The G-EO-Systems is an interesting new option in gait rehabilitation after stroke. The lower limb muscle activation patterns were comparable, a training thus feasible, and the positive case report warrants further clinical studies.

The Use of Prompts, Increased Accessibility, Visibility, and Aesthetics of the Stairwell to Promote Stair Use in a University Building

ERIC Educational Resources Information Center

van Nieuw-Amerongen, M. E.; Kremers, S. P. J.; de Vries, N. K.; Kok, G.

2011-01-01

Physical activity in the form of consistently opting for stair use instead of elevator use can have important health benefits. The article discusses a study assessing whether increasing the attractiveness and accessibility of a stairwell had an impact on stair use among students and employees of Maastricht University, the Netherlands. The…

Investigation of deformation mechanisms of staggered nanocomposites using molecular dynamics

NASA Astrophysics Data System (ADS)

Mathiazhagan, S.; Anup, S.

2016-08-01

Biological materials with nanostructure of regularly or stair-wise staggered arrangements of hard platelets reinforced in a soft protein matrix have superior mechanical properties. Applications of these nanostructures to ceramic matrix composites could enhance their toughness. Using molecular dynamics simulations, mechanical behaviour of the bio-inspired nanocomposites is studied. Regularly staggered model shows better flow behaviour compared to stair-wise staggered model due to the symmetrical crack propagation along the interface. Though higher stiffness and strength are obtained for stair-wise staggered models, rapid crack propagation reduces the toughness. Arresting this crack propagation could lead to superior mechanical properties in stair-wise staggered models.

Foot clearance and variability in mono- and multifocal intraocular lens users during stair navigation.

PubMed

Renz, Erik; Hackney, Madeleine; Hall, Courtney

2016-01-01

Intraocular lenses (IOLs) provide distance and near refraction and are becoming the standard for cataract surgery. Multifocal glasses increase variability of toe clearance in older adults navigating stairs and increase fall risk; however, little is known about the biomechanics of stair navigation in individuals with multifocal IOLs. This study compared clearance while ascending and descending stairs in individuals with monofocal versus multifocal IOLs. Eight participants with multifocal IOLs (4 men, 4 women; mean age = 66.5 yr, standard deviation [SD] = 6.26) and fifteen male participants with monofocal IOLs (mean age = 69.9 yr, SD = 6.9) underwent vision and mobility testing. Motion analysis recorded kinematic and custom software-calculated clearances in three-dimensional space. No significant differences were found between groups on minimum clearance or variability. Clearance differed for ascending versus descending stairs: the first step onto the stair had the greatest toe clearance during ascent, whereas the final step to the floor had the greatest heel clearance during descent. This preliminary study indicates that multifocal IOLs have similar biomechanic characteristics to monofocal IOLs. Given that step characteristics are related to fall risk, we can tentatively speculate that multifocal IOLs may carry no additional fall risk.

Stair-climbing capabilities of USU's T3 ODV mobile robot

NASA Astrophysics Data System (ADS)

Robinson, D. Reed; Wood, Carl G.

2001-09-01

A six-wheeled autonomous omni-directional vehicle (ODV) called T3 has been developed at Utah State University's (USU) Center for Self-Organizing and Intelligent Systems (CSOIS). This paper focuses on T3's ability to climb stairs using its unique configuration of 6 independently driven and steered wheels and active suspension height control. The ability of T3, or any similar vehicle, to climb stairs is greatly dependent on the chassis orientation relative to the stairs. Stability criteria is developed for any vehicle dimensions and orientation, on any staircase. All possible yaw and pitch angles on various staircases are evaluated to find vehicle orientations that will allow T3 to climb with the largest margin of stability. Different controller types are investigated for controlling vertical wheel movement with the objective of keeping all wheels in contact with the stairs, providing smooth load transfer between loaded and unloaded wheels, and maintaining optimum chassis pitch and roll angles. A controller is presented that uses feedback from wheel loading, vertical wheel position, and chassis orientation sensors. The implementation of the controller is described, and T3's stair climbing performance is presented and evaluated.

Influences of exit and stair conditions on human evacuation in a dormitory

NASA Astrophysics Data System (ADS)

Lei, Wenjun; Li, Angui; Gao, Ran; Wang, Xiaowei

2012-12-01

Evacuation processes of students are investigated by experiment and simulation. The experiment is performed for students evacuating from a dormitory with an exit and stairs. FDS+Evac is proposed to simulate the exit and stair dynamics of occupant evacuation. Concerning the exit and stair widths, we put forward some useful standpoints. Good agreement is achieved between the predicted results and experimental results. With the increase of exit width, a significant stratification phenomenon will be found in flow rate. Stratification phenomenon is that two different stable flow rates will emerge during the evacuation. And the flow rate curve looks like a ladder. The larger the exit width, the earlier the stratification phenomenon appears. When exit width is more than 2.0 m, the flow rate of each exit width is divided into two stable stages, and the evacuation times show almost no change. The judgment that the existence of stairs causes flow stratification is reasonable. By changing the width of the stairs, we proved that judgment. The smaller the width of BC, the earlier the stratification appears. We found that scenario 5 is the most adverse circumstance. Those results are helpful in performance-based design of buildings.

Acute Effects of Walking Exercise on Stair Negotiation in Sedentary and Physically Active Older Adults.

PubMed

Kunzler, Marcos R; da Rocha, Emmanuel S; Bobbert, Maarten F; Duysens, Jacques; Carpes, Felipe P

2017-07-01

In negotiating stairs, low foot clearance increases the risk of tripping and a fall. Foot clearance may be related to physical fitness, which differs between active and sedentary participants, and be acutely affected by exercise. Impaired stair negotiation could be an acute response to exercise. Here we determined acute changes in foot clearances during stair walking in sedentary (n = 15) and physically active older adults (n = 15) after prolonged exercise. Kinematic data were acquired during negotiation with a 3-steps staircase while participants walked at preferred speed, before and after 30 min walking at preferred speed and using a treadmill. Foot clearances were compared before and after exercise and between the groups. Sedentary older adults presented larger (0.5 cm for lead and 2 cm for trail leg) toe clearances in ascent, smaller (0.7 cm) heel clearance in the leading foot in descent, and larger (1 cm) heel clearance in the trailing foot in descent than physically active. Sedentary older adults negotiate stairs in a slightly different way than active older adults, and 30 min walking at preferred speed does not affect clearance in stair negotiation.

Markerless Knee Joint Position Measurement Using Depth Data during Stair Walking

PubMed Central

Mita, Akira; Yorozu, Ayanori; Takahashi, Masaki

2017-01-01

Climbing and descending stairs are demanding daily activities, and the monitoring of them may reveal the presence of musculoskeletal diseases at an early stage. A markerless system is needed to monitor such stair walking activity without mentally or physically disturbing the subject. Microsoft Kinect v2 has been used for gait monitoring, as it provides a markerless skeleton tracking function. However, few studies have used this device for stair walking monitoring, and the accuracy of its skeleton tracking function during stair walking has not been evaluated. Moreover, skeleton tracking is not likely to be suitable for estimating body joints during stair walking, as the form of the body is different from what it is when it walks on level surfaces. In this study, a new method of estimating the 3D position of the knee joint was devised that uses the depth data of Kinect v2. The accuracy of this method was compared with that of the skeleton tracking function of Kinect v2 by simultaneously measuring subjects with a 3D motion capture system. The depth data method was found to be more accurate than skeleton tracking. The mean error of the 3D Euclidian distance of the depth data method was 43.2 ± 27.5 mm, while that of the skeleton tracking was 50.4 ± 23.9 mm. This method indicates the possibility of stair walking monitoring for the early discovery of musculoskeletal diseases. PMID:29165396

Comparison between microprocessor-controlled ankle/foot and conventional prosthetic feet during stair negotiation in people with unilateral transtibial amputation.

PubMed

Agrawal, Vibhor; Gailey, Robert S; Gaunaurd, Ignacio A; O'Toole, Christopher; Finnieston, Adam A

2013-01-01

Contrary to stance-phase dorsiflexion of conventional prosthetic feet, the microprocessor-controlled Proprio foot permits swing-phase dorsiflexion on stairs. The purpose of this study was to compare Symmetry in External Work (SEW) between a microprocessor-controlled foot and conventional prosthetic feet in two groups with unilateral transtibial amputation (Medicare Functional Classification Levels K-Level-2 and K-Level-3) during stair ascent and descent. Ten subjects were evaluated while wearing three conventional prosthetic feet- solid ankle cushion heel (SACH), stationary attachment flexible endoskeleton (SAFE), and Talux-and the Proprio foot using a study socket and were given a 10- to 14-day accommodation period with each foot. Ground reaction forces were collected using F-scan sensors during stair ascent and descent. The SEW between the intact and amputated limbs was calculated for each foot. During stair ascent, the Proprio foot resulted in a higher interlimb symmetry than conventional prosthetic feet, with significant differences between the Pro prio and SACH/SAFE feet. The swing-phase dorsiflexion appeared to promote greater interlimb symmetry because it facilitated forward motion of the body, resulting in a heel-to-toe center of pressure trajectory. During stair descent, all feet had low symmetry without significant differences between feet. The movement strategy used when descending stairs, which is to roll over the edge of a step, had a greater influence on symmetry than the dorsiflexion features of prosthetic feet.

Stair negotiation as a rehabilitation intervention for enhancing recovery following total hip and knee replacement surgery.

PubMed

Gavin, James P; Immins, Tikki; Wainwright, Thomas

2017-05-01

Total hip replacement (THR) and total knee replacement (TKR) are common orthopaedic procedures. However, an optimal programme for post-operative rehabilitation has yet to be established. Stair negotiation is a challenging, habitual task, regularly used as a post-operative functional outcome measure; yet as a physical rehabilitation intervention it appears to be rarely used. The review purpose was to investigate the effectiveness of stair climbing as a rehabilitation intervention for THR and TKR patients. MEDLINE, PsycINFO, Science Citation Index, CINAHL, SPORTDiscus and the Cochrane Database of Systematic Reviews were searched. The systematic review targeted studies using stair negotiation as a rehabilitation intervention. Randomised and non-randomised controlled trials, pilot studies, and case studies were included; systematic reviews and meta-analyses were excluded. Of 650 articles identified, ten studies were eligible for review. A predefined data table to extract information from selected studies was used. Of the ten identified reports, two prehabilitation and eight rehabilitation studies included stair negotiation exercises as part of multi-modal physical interventions. Outcome measures were classified as: functional self-reported, perceptual, psychological and those relating to quality of life. Studies were methodologically heterogeneous and typically lacked adequate control groups. It was not possible to determine the impact of stair negotiation exercise on the positive outcomes of interventions. Stair negotiation warrants further investigation as a rehabilitation activity. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

Delayed Collapse of Wooden Folding Stairs

NASA Astrophysics Data System (ADS)

Krentowski, Janusz; Chyzy, Tadeusz

2017-10-01

During operation of folding stairs, a fastener joining the ladder hanger with the frame was torn off. A person using the stairs sustained serious injury. In several dozen other locations similar accidents were observed. As a result of inspections, some threaded parts of the screws were found in the gaps between the wooden elements of the stairs’ flaps. In the construction a hatch made of wooden strips is attached to an external frame by means of metal hangers. Laboratory strength tests were conducted on three samples made of wooden elements identical to the ones used in the damaged stairs. Due to complex load distribution mechanism acting on the base of the structure, a three-dimensional FEM model was created. An original software was used for calculations. Five computational model variants were considered. As a result of the numerical analyses, it was unquestionably shown that faulty connections were the cause of the destruction of the stairs. The weakest link in the load transmission chain were found to have been the screws connecting the hatch board with the hangers.

Specific effects of a calorie-based intervention on stair climbing in overweight commuters.

PubMed

Lewis, Amanda L; Eves, Frank F

2011-10-01

Point-of-choice prompts consistently increase stair climbing; a greater increase in overweight than normal weight individuals was reported in a multi-component worksite campaign. The purpose of this study is to investigate effects of a multi-component campaign, on stair climbing, in a public access setting. In an interrupted-time-series-design, baseline observations (2 weeks) preceded a 2-week point-of-choice prompt. An additional message, positioned at the top of the climb for a further 6-week period, summarised the calorific consequences of a single ascent. Inconspicuous observers recorded traveller's methods of ascent, coded by sex and weight status, twice a week between 08:00 and 09:59. At baseline, the overweight chose stairs less than normal weight individuals. The multi-component campaign targeting weight control reversed this bias, increasing stair climbing only in overweight individuals. The specificity of the effect confirms the appeal of this lifestyle activity for the overweight. The discussion focuses on how intentions to control weight may be converted into behaviour.

Novel knee joint mechanism of transfemoral prosthesis for stair ascent.

PubMed

Inoue, Koh; Wada, Takahiro; Harada, Ryuchi; Tachiwana, Shinichi

2013-06-01

The stability of a transfemoral prosthesis when walking on flat ground has been established by recent advances in knee joint mechanisms and their control methods. It is, however, difficult for users of a transfemoral prosthesis to ascend stairs. This difficulty is mainly due to insufficient generation of extension moment around the knee joint of the prosthesis to lift the body to the next step on the staircase and prevent any unexpected flexion of the knee joint in the stance phase. Only a prosthesis with an actuator has facilitated stair ascent using a step-over-step gait (1 foot is placed per step). However, its use has issues associated with the durability, cost, maintenance, and usage environment. Therefore, the purpose of this research is to develop a novel knee joint mechanism for a prosthesis that generates an extension moment around the knee joint in the stance phase during stair ascent, without the use of any actuators. The proposed mechanism is based on the knowledge that the ground reaction force increases during the stance phase when the knee flexion occurs. Stair ascent experiments with the prosthesis showed that the proposed prosthesis can realize stair ascent without any undesirable knee flexion. In addition, the prosthesis is able to generate a positive knee joint moment power in the stance phase even without any power source.

Whole-body angular momentum during stair walking using passive and powered lower-limb prostheses.

PubMed

Pickle, Nathaniel T; Wilken, Jason M; Aldridge, Jennifer M; Neptune, Richard R; Silverman, Anne K

2014-10-17

Individuals with a unilateral transtibial amputation have a greater risk of falling compared to able-bodied individuals, and falling on stairs can lead to serious injuries. Individuals with transtibial amputations have lost ankle plantarflexor muscle function, which is critical for regulating whole-body angular momentum to maintain dynamic balance. Recently, powered prostheses have been designed to provide active ankle power generation with the goal of restoring biological ankle function. However, the effects of using a powered prosthesis on the regulation of whole-body angular momentum are unknown. The purpose of this study was to use angular momentum to evaluate dynamic balance in individuals with a transtibial amputation using powered and passive prostheses relative to able-bodied individuals during stair ascent and descent. Ground reaction forces, external moment arms, and joint powers were also investigated to interpret the angular momentum results. A key result was that individuals with an amputation had a larger range of sagittal-plane angular momentum during prosthetic limb stance compared to able-bodied individuals during stair ascent. There were no significant differences in the frontal, transverse, or sagittal-plane ranges of angular momentum or maximum magnitude of the angular momentum vector between the passive and powered prostheses during stair ascent or descent. These results indicate that individuals with an amputation have altered angular momentum trajectories during stair walking compared to able-bodied individuals, which may contribute to an increased fall risk. The results also suggest that a powered prosthesis provides no distinct advantage over a passive prosthesis in maintaining dynamic balance during stair walking. Copyright © 2014 Elsevier Ltd. All rights reserved.

Trunk and lower limb biomechanics during stair climbing in people with and without symptomatic femoroacetabular impingement.

PubMed

Hammond, Connor A; Hatfield, Gillian L; Gilbart, Michael K; Garland, S Jayne; Hunt, Michael A

2017-02-01

Femoroacetabular impingement is a pathomechanical hip condition leading to pain and impaired physical function. It has been shown that those with femoroacetabular impingement exhibit altered gait characteristics during level walking and stair climbing, and decreased muscle force production during isometric muscle contractions. However, no studies to-date have looked at trunk kinematics or muscle activation during dynamic movements such as stair climbing in this patient population. The purpose of this study was to compare biomechanical outcomes (trunk and lower limb kinematics as well as lower limb kinetics and muscle activation) during stair climbing in those with and without symptomatic femoroacetabular impingement. Trunk, hip, knee and ankle kinematics, as well as hip, knee and ankle kinetics and muscle activity of nine lower limb muscles were collected during stair climbing for 20 people with clinical and radiographic femoroacetabular impingement and compared to 20 age- and sex-matched pain-free individuals. Those with femoroacetabular impingement ascended the stairs slower (effect size=0.82), had significantly increased peak trunk forward flexion angles (effect size=0.99) and external hip flexion moments (effect size=0.94) and had decreased peak external knee flexion moments (effect size=0.90) compared to the control group. Findings from this study indicate that while those with and without femoroacetabular impingement exhibit many biomechanical similarities when ascending stairs, differences in trunk forward flexion and joint kinetics indicate some important differences. Further longitudinal research is required to elucidate the cause of these differences as well as the clinical relevance. Copyright © 2017 Elsevier Ltd. All rights reserved.

Criterion-related validity of self-reported stair climbing in older adults.

PubMed

Higueras-Fresnillo, Sara; Esteban-Cornejo, Irene; Gasque, Pablo; Veiga, Oscar L; Martinez-Gomez, David

2018-02-01

Stair climbing is an activity of daily living that might contribute to increase levels of physical activity (PA). To date, there is no study examining the validity of climbing stairs assessed by self-report. The aim of this study was, therefore, to examine the validity of estimated stair climbing from one question included in a common questionnaire compared to a pattern-recognition activity monitor in older adults. A total of 138 older adults (94 women), aged 65-86 years (70.9 ± 4.7 years), from the IMPACT65 + study participated in this validity study. Estimates of stair climbing were obtained from the European Prospective Investigation into Cancer and Nutrition (EPIC) PA questionnaire. An objective assessment of stair climbing was obtained with the Intelligent Device for Energy Expenditure and Activity (IDEEA) monitor. The correlation between both methods to assess stair climbing was fair (ρ = 0.22, p = 0.008 for PA energy expenditure and ρ = 0.26, p = 0.002 for duration). Mean differences between self-report and the IDEEA were 7.96 ± 10.52 vs. 9.88 ± 3.32 METs-min/day for PA energy expenditure, and 0.99 ± 1.32 vs. 1.79 ± 2.02 min/day for duration (both Wilcoxon test p < 0.001). Results from the Bland-Altman analysis indicate that bias between both instruments were -1.91 ± 10.30 METs-min/day and -0.80 ± 1.99 min/day, and corresponding limits of agreement for the two instruments were from 18.27 to -22.10 METs-min/day and from 3.09 to -4.70 min/day, respectively. Our results indicate that self-reported stair climbing has modest validity to accurately rank old age participants, and underestimates both PAEE and its duration, as compared with an objectively measured method.

Metabolics of stair ascent with a powered transfemoral prosthesis.

PubMed

Ledoux, E D; Lawson, B E; Shultz, A H; Bartlett, H L; Goldfarb, M

2015-01-01

This paper evaluates the effectiveness of a powered knee and ankle prosthesis for stair ascent through a metabolic assessment comparing energy expenditure of a single transfemoral amputee subject while ascending stairs with the powered prosthesis relative to his passive daily use device, as well as comparing the kinematics and kinetics obtained with the passive prosthesis to healthy biomechanics. The subject wore a portable system that measured pulmonary gaseous exchange rates of oxygen and carbon dioxide while he ascended stairs with each of the prostheses in alternating tests. The results indicated that the amputee's energy expenditure decreased by 32 percent while climbing with the powered prosthesis as compared to his passive one, and the kinematics and kinetics achieved were representative of healthy biomechanics.

Mirror, Mirror by the Stairs: The Impact of Mirror Exposure on Stair versus Elevator Use in College Students.

PubMed

Hodgin, Katie L; Graham, Dan J

2016-01-01

Previous research has indicated that self-awareness-inducing mirrors can successfully incite behaviors that align with one's personal values, such as helping others. Other research has found a large discrepancy between the high percentage of young adults who report valuing the healthfulness of physical activity (PA) and the low percentage who actually meet PA participation standards. However, few studies have examined how mirror exposure and both perceived and actual body size influence highly valued PA participation among college students. The present study assessed stair versus elevator use on a western college campus and hypothesized that mirror exposure would increase the more personally healthy transportation method of stair use. In accordance with previous research, it was also hypothesized that males and those with a lower body mass index (BMI) would be more likely to take the stairs, and that body size distorting mirrors would impact the stair-elevator decision. One hundred sixty-seven students (51% male) enrolled in an introductory psychology course were recruited to take a survey about their "transportation choices" at an indoor campus parking garage. Participants were individually exposed to either no mirror, a standard full-length mirror, or a full-length mirror manipulated to make the reflected body size appear either slightly thinner or slightly wider than normal before being asked to go to the fourth floor of the garage for a survey. Participants' choice of floor-climbing method (stairs or elevator) was recorded, and they were administered an Internet-based survey assessing demographic information, BMI, self-awareness, perceived body size, and other variables likely to be associated with stair use. Results from logistic regression analyses revealed that participants who were not exposed to a mirror [odds ratios (OR) = 0.37, 95% CI: 0.14-0.96], males (OR = 0.33, 95% CI: 0.13-0.85), those with lower BMI (OR = 0.84, 95% CI: 0.71-0.99), those with higher exercise participation (OR = 1.09, 95% CI: 1.02-1.18), and those engaging in more unhealthy weight-control behaviors (OR = 1.55, 95% CI: 1.14-2.11) showed increased odds of taking the stairs. Implications and future directions are discussed.

A multistage controlled intervention to increase stair climbing at work: effectiveness and process evaluation.

PubMed

Bellicha, Alice; Kieusseian, Aurélie; Fontvieille, Anne-Marie; Tataranni, Antonio; Copin, Nane; Charreire, Hélène; Oppert, Jean-Michel

2016-04-11

Stair climbing helps to accumulate short bouts of physical activity throughout the day as a strategy for attaining recommended physical activity levels. There exists a need for effective long-term stair-climbing interventions that can be transferred to various worksite settings. The aims of this study were: 1) to evaluate short- and long-term effectiveness of a worksite stair-climbing intervention using an objective measurement of stair climbing and a controlled design; and 2) to perform a process evaluation of the intervention. We performed a controlled before-and-after study. The study was conducted in two corporate buildings of the same company located in Paris (France), between September, 2013 and September, 2014. The status of either "intervention site" or "control site" was assigned by the investigators. Participants were on-site employees (intervention site: n = 783; control site: n = 545 at baseline). Two one-month intervention phases using signs (intervention phase 1) and enhancement of stairwell aesthetics (intervention phase 2) were performed. The main outcome was the change in stair climbing, measured with automatic counters and expressed in absolute counts/day/100 employees and percent change compared to baseline. Qualitative outcomes were used to describe the intervention process. Stair climbing significantly increased at the intervention site (+18.7%) but decreased at the control site (-13.3%) during the second intervention phase (difference between sites: +4.6 counts/day/100 employees, p < 0.001). After the intervention and over the long term, stair climbing returned to baseline levels at the intervention site, but a significant difference between sites was found (intervention site vs. control site: +2.9 counts/day/100 employees, p < 0.05). Some important facets of the intervention were implemented as intended but other aspects had to be adapted. The main difficulty reported by the company's staff members lay in matching the internal communications rules with critical intervention criteria. The program was maintained at the setting level after the end of the study. This study shows a successful stair-climbing intervention at the worksite. The main barriers to adoption and implementation were related to location and visibility of posters. Process evaluation was useful in identifying these barriers throughout the study, and in finding appropriate solutions.

Stair-shaped Achilles tendon lengthening in continuity - A new method to treat equinus deformity in patients with spastic cerebral palsy.

PubMed

Li, Zhengxun; Zhang, Ning; Wang, Yang; Cao, Songhua; Huang, Zheng; Hu, Yong

2017-10-27

Equinus of the ankle is a common deformity in spastic cerebral palsy. Achilles tendon lengthening is one of the effective options for the treatment of equinus deformity. In the study, a new stair-shaped Achilles tendon lengthening (ATL) procedure that preserves of the tendon continuity was performed in 28 tendons with equinus deformity (20 patients, mean age=10.5±2.6 years). The results were compared with a group of patients treated with the Z-lengthening procedure. During the latest follow-up visit, the American Orthopaedic Foot & Ankle Society (AOFAS) Ankle-Hindfoot scale score was much higher in the stair-shaped ATL group than in the Z-lengthening group (p<0.05). The two groups showed similar surgical correction angle after ATL(37.2±3.5° for stair-shaped ATL and 36.1±4.5° for Z-lengthening). During the latest follow-up visit, the correction angle in the Z-lengthening group decreased to 21.6±4.3°, which was lower than in the stair-shaped ATL group (29.0±3.1°; p<0.05). In addition, the data regarding the time required by each patient before being able to start rehabilitation and walking as well as gaining better stability for running indicated that the stair-shaped ATL group recovered significantly quicker than the Z-lengthening group. The stair-shaped ATL procedure resulted in a successful correction of the equinus deformity in spastic cerebral palsy, with the advantage of preserving a degree of continuity without a complete section of the tendon. This confers greater antigravity stability and quicker recovery in patients. Copyright © 2017 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

Hip biomechanics during stair ascent and descent in people with and without hip osteoarthritis.

PubMed

Hall, Michelle; Wrigley, Tim V; Kean, Crystal O; Metcalf, Ben R; Bennell, Kim L

2017-07-01

Hip osteoarthritis (OA) is often associated with pain and impaired function. Understanding biomechanical alterations in patients with hip OA during challenging activities such as stair use is important to inform treatments. The aim of this study was to determine whether kinematics and kinetics during stair ambulation differed between people with hip OA and healthy controls. Fifteen participants with symptomatic and radiographic hip OA and 15 asymptomatic healthy controls underwent 3-D motion analysis during stair ascent and descent. Trunk, pelvis, and hip kinematics as well as hip kinetics were evaluated. Analyses were performed unadjusted and adjusted for speed and leg length. In both the unadjusted and adjusted analyses, participants with hip OA ascended stairs with less hip range of motion in all three planes and a lower peak external rotation moment compared to controls. In the unadjusted analysis, hip OA participants descended stairs with greater ipsilateral trunk lean, less sagittal plane range of motion, lower peak extension moment, lower peak external rotation moment, and greater hip adduction moment impulse compared to controls. In the adjusted results, peak internal rotation moment and hip adduction moment impulse were greater in hip OA participants compared to controls. Findings show that individuals with hip OA display limited range of hip joint movement, particularly during stair ascent, and overall indicate the use of strategies (e.g., trunk lean; lower peak external rotation moment; higher adduction moment impulse) that implicate altered hip abductor function. Future research is required to further understand the implications of these findings on hip OA. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1505-1514, 2017. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Toward Autonomous Multi-floor Exploration: Ascending Stairway Localization and Modeling

DTIC Science & Technology

2013-03-01

robots have traditionally been restricted to single floors of a building or outdoor areas free of abrupt elevation changes such as curbs and stairs ...solution to this problem and is motivated by the rich potential of an autonomous ground robot that can climb stairs while exploring a multi-floor...parameters of the stairways, the robot could plan a path that traverses the stairs in order to explore the frontier at other elevations that were previously

Ascending Stairway Modeling: A First Step Toward Autonomous Multi-Floor Exploration

DTIC Science & Technology

2012-10-01

Many robotics platforms are capable of ascending stairways, but all existing approaches for autonomous stair climbing use stairway detection as a...the rich potential of an autonomous ground robot that can climb stairs while exploring a multi-floor building. Our proposed solution to this problem is...over several steps. However, many ground robots are not capable of traversing tight spiral stairs , and so we do not focus on these types. The stairway is

Analysis of foot clearance in firefighters during ascent and descent of stairs.

PubMed

Kesler, Richard M; Horn, Gavin P; Rosengren, Karl S; Hsiao-Wecksler, Elizabeth T

2016-01-01

Slips, trips, and falls are a leading cause of injury to firefighters with many injuries occurring while traversing stairs, possibly exaggerated by acute fatigue from firefighting activities and/or asymmetric load carriage. This study examined the effects that fatigue, induced by simulated firefighting activities, and hose load carriage have on foot clearance while traversing stairs. Landing and passing foot clearances for each stair during ascent and descent of a short staircase were investigated. Clearances decreased significantly (p < 0.05) post-exercise for nine of 12 ascent parameters and increased for two of eight descent parameters. Load carriage resulted in significantly decreased (p < 0.05) clearance over three ascent parameters, and one increase during descent. Decreased clearances during ascent caused by fatigue or load carriage may result in an increased trip risk. Increased clearances during descent may suggest use of a compensation strategy to ensure stair clearance or an increased risk of over-stepping during descent. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Day-to-day consistency of lower extremity kinematics during stair ambulation in 24-45 years old athletes.

PubMed

Husa-Russell, Johanna; Ukelo, Thomas; List, Renate; Lorenzetti, Silvio; Wolf, Peter

2011-04-01

Before making interpretations on the effects of interventions or on the features of pathological gait patterns during stair ambulation, the day-to-day consistency of the investigated variables must be established. In this article, the day-to-day consistency was determined for kinematic variables during barefoot stair ambulation. Ten healthy athletes performed two gait analysis sessions, at least one week apart, utilizing a marker set of 47 skin markers, and a functional joint center/axes determination. Being found on limits of agreement and mean differences between the repeated stair ambulation sessions, totally 43 ranges of motions were examined at the hip, knee, ankle, and midfoot joints. The day-to-day consistency was generally in the magnitude of three degrees, irrespective of test condition, investigated joint, or regarded cardinal body plane. The reported values of the day-to-day consistency provide guidelines to distinguish between pathological and healthy gait patterns, and thresholds to determine minimal effects of interventions during stair ambulation. Copyright © 2011 Elsevier B.V. All rights reserved.

Does a microprocessor-controlled prosthetic knee affect stair ascent strategies in persons with transfemoral amputation?

PubMed

Aldridge Whitehead, Jennifer M; Wolf, Erik J; Scoville, Charles R; Wilken, Jason M

2014-10-01

Stair ascent can be difficult for individuals with transfemoral amputation because of the loss of knee function. Most individuals with transfemoral amputation use either a step-to-step (nonreciprocal, advancing one stair at a time) or skip-step strategy (nonreciprocal, advancing two stairs at a time), rather than a step-over-step (reciprocal) strategy, because step-to-step and skip-step allow the leading intact limb to do the majority of work. A new microprocessor-controlled knee (Ottobock X2(®)) uses flexion/extension resistance to allow step-over-step stair ascent. We compared self-selected stair ascent strategies between conventional and X2(®) prosthetic knees, examined between-limb differences, and differentiated stair ascent mechanics between X2(®) users and individuals without amputation. We also determined which factors are associated with differences in knee position during initial contact and swing within X2(®) users. Fourteen individuals with transfemoral amputation participated in stair ascent sessions while using conventional and X2(®) knees. Ten individuals without amputation also completed a stair ascent session. Lower-extremity stair ascent joint angles, moment, and powers and ground reaction forces were calculated using inverse dynamics during self-selected strategy and cadence and controlled cadence using a step-over-step strategy. One individual with amputation self-selected a step-over-step strategy while using a conventional knee, while 10 individuals self-selected a step-over-step strategy while using X2(®) knees. Individuals with amputation used greater prosthetic knee flexion during initial contact (32.5°, p = 0.003) and swing (68.2°, p = 0.001) with higher intersubject variability while using X2(®) knees compared to conventional knees (initial contact: 1.6°, swing: 6.2°). The increased prosthetic knee flexion while using X2(®) knees normalized knee kinematics to individuals without amputation during swing (88.4°, p = 0.179) but not during initial contact (65.7°, p = 0.002). Prosthetic knee flexion during initial contact and swing were positively correlated with prosthetic limb hip power during pull-up (r = 0.641, p = 0.046) and push-up/early swing (r = 0.993, p < 0.001), respectively. Participants with transfemoral amputation were more likely to self-select a step-over-step strategy similar to individuals without amputation while using X2(®) knees than conventional prostheses. Additionally, the increased prosthetic knee flexion used with X2(®) knees placed large power demands on the hip during pull-up and push-up/early swing. A modified strategy that uses less knee flexion can be used to allow step-over-step ascent in individuals with less hip strength.

7. INTERIOR, VIEW FROM ENTRANCE TOWARD ENCLOSED STAIRS AND REAR ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. INTERIOR, VIEW FROM ENTRANCE TOWARD ENCLOSED STAIRS AND REAR DOOR - Mulliken-Spragins Tenant House, National Museum of American History, Smithsonian Institution, Washington, District of Columbia, DC

16. ENTRANCE HALL, VIEW OF HALLWAY LOOKING TOWARD STAIR, NOTE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

16. ENTRANCE HALL, VIEW OF HALLWAY LOOKING TOWARD STAIR, NOTE PEDIMENTED DOORWAYS, CHINESE WALLPAPER, DENTICULATED CORNICE, PANELED DADO - Mt. Harmon Plantation at World's End, Earleville, Cecil County, MD

Clomiphene Stair-Step Protocol for Women With Polycystic Ovary Syndrome.

PubMed

Jones, Tiffanny; Ho, Jacqueline R; Gualtieri, Marc; Bruno-Gaston, Janet; Chung, Karine; Paulson, Richard J; Bendikson, Kristin A

2018-01-01

To compare time to ovulation, ovulation rates, and side effect profile of traditional and the stair-step protocol for ovulation induction using clomiphene citrate in women with polycystic ovary syndrome (PCOS). We performed a retrospective study of women seeking care for infertility with a diagnosis of PCOS at a university-based infertility clinic from July 2012 to July 2014. We included patients who were resistant to the initial starting dose of 50 mg clomiphene. The primary outcome was time to ovulation. Secondary outcomes included ovulation rates, clinical pregnancy rates, and mild and moderate-to-severe side effects based on dose. For the traditional protocol, higher doses of clomiphene were used each subsequent month if no ovulation occurred. For the stair-step protocol, higher doses of clomiphene were given 7 days after the last dose if no dominant follicles were seen on ultrasonography. Our study had 80% power to detect a 20% difference in ovulation. One hundred nine patients were included in the analysis with 66 (60.6%) in the traditional and 43 (39.4%) in the stair-step protocol. Age and body mass index were similar between groups. The time to ovulation was decreased in the stair-step protocol group compared with the traditional protocol group (23.1±0.9 days vs 47.5±6.3 days). Ovulation rates were increased in the stair-step group compared with the traditional group at 150 mg (16 [37%] vs 8 [12%], P=.004) and at 200 mg (9 [21%] vs 3 [5%], P=.01). Pregnancy rates were similar between groups once ovulation was achieved (12 [18.1%] vs 7 [16.3%], P=.08). The stair-step protocol had an increased incidence of mild side effects (vasomotor flushes, headaches, gastrointestinal disturbance, mastalgia, changes in mood; 18 [41%] vs 8 [12%]), but there was no difference in the incidence of severe side effects (headaches, visual disturbances). For women with PCOS, the stair-step clomiphene protocol is associated with decreased time to ovulation and increased ovulation rates at higher doses when compared with the traditional protocol.

14. DETAIL VIEW OF STAIRS AND OVERLOOK AT SOUTH APPROACH, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

14. DETAIL VIEW OF STAIRS AND OVERLOOK AT SOUTH APPROACH, VIEW LOOKING NORTHEAST - Crooked River High Bridge, Spanning Crooked River Gorge at Dalles-California Highway, Terrebonne, Deschutes County, OR

20. VIEW, LOOKING NORTH FROM BOSTON, SHOWING RAILING, PEDESTRIAN STAIR, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

20. VIEW, LOOKING NORTH FROM BOSTON, SHOWING RAILING, PEDESTRIAN STAIR, AND '10 SMOOT' MARKER (see data pages) - Harvard Bridge, Spanning Charles River at Massachusetts Avenue, Boston, Suffolk County, MA

Hallway, bunkhouse, second floor interior. Looking east showing the stair ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Hallway, bunkhouse, second floor interior. Looking east showing the stair railing, light from skylight above, and original 5 panel wood doors. - Sespe Ranch, Bunkhouse, 2896 Telegraph Road, Fillmore, Ventura County, CA

17. Missile mural, third flight of stairs. Lyon Whiteman ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

17. Missile mural, third flight of stairs. Lyon - Whiteman Air Force Base, Minuteman Missile Launch Facility Trainer T-12, Northeast of Oscar-01 Missile Alert Facility, Knob Noster, Johnson County, MO

29 CFR 1910.24 - Fixed industrial stairs.

Code of Federal Regulations, 2010 CFR

2010-07-01

... OCCUPATIONAL SAFETY AND HEALTH STANDARDS Walking-Working Surfaces § 1910.24 Fixed industrial stairs. (a... load anticipated but never of less strength than to carry safely a moving concentrated load of 1,000...

5. Light tower, newel post and stairs, looking east ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. Light tower, newel post and stairs, looking east - Great Duck Island Light Station, At southern tip of Great Duck Island southeast of Bass Harbor & northeast of Frenchboro, Frenchboro, Hancock County, ME

Patterns in the knee flexion-extension moment profile during stair ascent and descent in patients with total knee arthroplasty.

PubMed

McClelland, Jodie A; Feller, Julian A; Menz, Hylton B; Webster, Kate E

2014-06-03

The aim of this study was to investigate the prevalence of abnormal knee biomechanical patterns in 40 patients with a modern TKA prosthesis, compared to 40 matched control participants when ascending and descending stairs. Fewer patients were able to ascend (65%) or descend stairs (53%) unassisted than controls (83%). Of the participants who could ascend and descend, cluster analysis classified most patients (up to 77%) as demonstrating a similar knee moment pattern as all controls. A small subgroup of patients who completed the tasks did so with distinctly abnormal biomechanics compared to other patients and controls. These findings suggest that recovery of normal stair climbing is possible. However, rehabilitation might be more effective if it were tailored to account for these differences between patients. Copyright © 2014 Elsevier Ltd. All rights reserved.

Performance of women with fibromyalgia in walking up stairs while carrying a load.

PubMed

Collado-Mateo, Daniel; Adsuar, José C; Olivares, Pedro R; Dominguez-Muñoz, Francisco J; Maestre-Cascales, Cristina; Gusi, Narcis

2016-01-01

Background. Fibromyalgia is a chronic disease characterized by widespread pain and other associated symptoms. It has a relevant impact on physical fitness and the ability to perform daily living tasks. The objective of the study was to analyze the step-by-step-performance and the trunk tilt of women with fibromyalgia in the 10-step stair climbing test compared with healthy controls. Methods. A cross-sectional study was carried out. Twelve women suffering from fibromyalgia and eight healthy controls were recruited from a local association. Participants were asked to climb 10 stairs without carrying a load and 10 stairs carrying a load of 5 kg in each hand. Mediolateral trunk tilt was assessed using the "Functional Assessment of Biomechanics (FAB)" wireless motion capture device, and the time between steps was assessed via weight-bearing insoles. Results. Trunk tilt in the stair-climbing task carrying a load was significantly higher in women with fibromyalgia when compared to the healthy controls (2.31 (0.63) vs. 1.69 (0.51) respectively). The effect of carrying a load was significantly higher for women with fibromyalgia compared with healthy controls at the intermediate and final part of the task. Discussion. Trunk tilt during stair climbing while carrying a load was higher in women with FM, which could increase the risk of falling. Additionally, women with FM experienced a higher pace slowdown as a consequence of the load, which supports the need of including specific strength and resistance training to physical therapies for this population.

Influence of AZO stair-like transparent layers on GaN-based light-emitting diodes

NASA Astrophysics Data System (ADS)

Liou, Syuan-Hao; Tsai, Jung-Hui; Liu, Wen-Chau; Lin, Pao-Sheng; Chen, Yu-Chi

2017-10-01

The GaN-based light-emitting diodes (LEDs) with various height ratios of aluminum-doped zinc oxide (AZO) stair-like transparent layers are fabricated and comparatively investigated. The characteristics of the LEDs with conventional plane AZO transparent layer (device A) and AZO stair-like transparent layers having height ratios of 1:1:1 (device B), 1.5:1:0.5 (device C), and 0.5:1:1.5 (device D) are compared. Attributed that the lower resistance is formed in the thinner AZO film of the stair-like structure, the current crowding effect is improved for extending the whole current-spreading area. Experimentally, the forward turn-on voltages of the LEDs are reduced from 3.68 V to 3.42 V as the plane AZO transparent layer is processed to form the stair-like transparent layers with height ratio of 1:1:1. In addition, the light luminous flux, output power, external quantum efficiency, and wall-plug efficiency of the device B are enhanced by 30.5, 12.1, 22.2, and 20.7%, respectively, as compared to the traditional device with plane AZO transparent layer.

Stair ascent with an innovative microprocessor-controlled exoprosthetic knee joint.

PubMed

Bellmann, Malte; Schmalz, Thomas; Ludwigs, Eva; Blumentritt, Siegmar

2012-12-01

Climbing stairs can pose a major challenge for above-knee amputees as a result of compromised motor performance and limitations to prosthetic design. A new, innovative microprocessor-controlled prosthetic knee joint, the Genium, incorporates a function that allows an above-knee amputee to climb stairs step over step. To execute this function, a number of different sensors and complex switching algorithms were integrated into the prosthetic knee joint. The function is intuitive for the user. A biomechanical study was conducted to assess objective gait measurements and calculate joint kinematics and kinetics as subjects ascended stairs. Results demonstrated that climbing stairs step over step is more biomechanically efficient for an amputee using the Genium prosthetic knee than the previously possible conventional method where the extended prosthesis is trailed as the amputee executes one or two steps at a time. There is a natural amount of stress on the residual musculoskeletal system, and it has been shown that the healthy contralateral side supports the movements of the amputated side. The mechanical power that the healthy contralateral knee joint needs to generate during the extension phase is also reduced. Similarly, there is near normal loading of the hip joint on the amputated side.

72. 451 MADISON AVENUE, GRAND STAIR, ZODIAC CLOCK WITH DECORATIVE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

72. 451 MADISON AVENUE, GRAND STAIR, ZODIAC CLOCK WITH DECORATIVE CARVING BY STANFORD WHITE AND AUGUSTUS SAINT-GAUDENS - Villard Houses, 451-457 Madison Avenue & 24 East Fifty-first Street, New York County, NY

80. GOVERNOR'S ELEVATOR, LOOKING SOUTH WITH STAIRS TO ATTIC IN ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

80. GOVERNOR'S ELEVATOR, LOOKING SOUTH WITH STAIRS TO ATTIC IN BACKGROUND (NOTE TIFFANY STAINED GLASS SKYLIGHT ABOVE AND GLASS FLOOR TILE BELOW - Maryland State House, State Circle, Annapolis, Anne Arundel County, MD

Detail of front entry stairs showing original boot scrape set ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Detail of front entry stairs showing original boot scrape set in concrete, facing northwest. - Albrook Air Force Station, Company Officer's Quarters, East side of Canfield Avenue, Balboa, Former Panama Canal Zone, CZ

36. NORTH AND EAST SIDES OF MAIN STAIR HALL SHOWING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

36. NORTH AND EAST SIDES OF MAIN STAIR HALL SHOWING STAIRWAY, NORTH SCULPTURE PANEL, AND CEILING VAULT; LOOKING NORTHEAST (Harms & Wieskamp) - Dairy Industry Building, Iowa State University campus, Ames, Story County, IA

33. Third floor, looking north, elevator and central stair to ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

33. Third floor, looking north, elevator and central stair to the right (original ice manufacturing floor) - Sheffield Farms Milk Plant, 1075 Webster Avenue (southwest corner of 166th Street), Bronx, Bronx County, NY

VIEW OF FIRST FLOOR HALL AND STAIRS LEADING TO SECOND ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW OF FIRST FLOOR HALL AND STAIRS LEADING TO SECOND FLOOR OF PAULINE KILKER HOUSE, FACING SOUTHWEST. - Pauline Kilker House, 1410 North Lincoln Avenue-3300 West Laurel Street, Tampa, Hillsborough County, FL

Wa-Chair: A concept for development of economical stair-climbing wheelchair

NASA Astrophysics Data System (ADS)

Jyoti Baishya, Nayan; Ogai, Harutoshi

2018-02-01

In this paper, a concept for development of cost effective and reliable stair climbing wheelchair is being proposed. Slider-crank mechanism is being used to compensate for any variation in inclination angle of the wheelchair during ascent or descent on stairs. Controlling wheelchair’s inclination angle can reduce risk for the rider as it prevents the wheelchair from toppling. A prototype is being developed to validate proposed mechanism. Proposed mechanism allows rider to view in the direction of progress which adds additional safety to the rider.

Reducing the stair step effect of layer manufactured surfaces by ball burnishing

NASA Astrophysics Data System (ADS)

Hiegemann, Lars; Agarwal, Chiranshu; Weddeling, Christian; Tekkaya, A. Erman

2016-10-01

The layer technology enables fast and flexible additive manufacturing of forming tools. The disadvantages of this system is the formation of stair steps in the range of tool radii. Within this work a new method to smooth this stair steps by ball burnishing is introduced. This includes studies on the general feasibility of the process and the determination of the influence of the rolling parameters. The investigations are carried out experimentally and numerically. Ultimately, the gained knowledge is applied to finish a deep drawing tool which is manufactured by layer technology.

Planning paths through a spatial hierarchy - Eliminating stair-stepping effects

NASA Technical Reports Server (NTRS)

Slack, Marc G.

1989-01-01

Stair-stepping effects are a result of the loss of spatial continuity resulting from the decomposition of space into a grid. This paper presents a path planning algorithm which eliminates stair-stepping effects induced by the grid-based spatial representation. The algorithm exploits a hierarchical spatial model to efficiently plan paths for a mobile robot operating in dynamic domains. The spatial model and path planning algorithm map to a parallel machine, allowing the system to operate incrementally, thereby accounting for unexpected events in the operating space.

Peak oxygen consumption measured during the stair-climbing test in lung resection candidates.

PubMed

Brunelli, Alessandro; Xiumé, Francesco; Refai, Majed; Salati, Michele; Di Nunzio, Luca; Pompili, Cecilia; Sabbatini, Armando

2010-01-01

The stair-climbing test is commonly used in the preoperative evaluation of lung resection candidates, but it is difficult to standardize and provides little physiologic information on the performance. To verify the association between the altitude and the V(O2peak) measured during the stair-climbing test. 109 consecutive candidates for lung resection performed a symptom-limited stair-climbing test with direct breath-by-breath measurement of V(O2peak) by a portable gas analyzer. Stepwise logistic regression and bootstrap analyses were used to verify the association of several perioperative variables with a V(O2peak) <15 ml/kg/min. Subsequently, multiple regression analysis was also performed to develop an equation to estimate V(O2peak) from stair-climbing parameters and other patient-related variables. 56% of patients climbing <14 m had a V(O2peak) <15 ml/kg/min, whereas 98% of those climbing >22 m had a V(O2peak) >15 ml/kg/min. The altitude reached at stair-climbing test resulted in the only significant predictor of a V(O2peak) <15 ml/kg/min after logistic regression analysis. Multiple regression analysis yielded an equation to estimate V(O2peak) factoring altitude (p < 0.0001), speed of ascent (p = 0.005) and body mass index (p = 0.0008). There was an association between altitude and V(O2peak) measured during the stair-climbing test. Most of the patients climbing more than 22 m are able to generate high values of V(O2peak) and can proceed to surgery without any additional tests. All others need to be referred for a formal cardiopulmonary exercise test. In addition, we were able to generate an equation to estimate V(O2peak), which could assist in streamlining the preoperative workup and could be used across different settings to standardize this test. Copyright (c) 2010 S. Karger AG, Basel.

Influence of working memory and executive function on stair ascent and descent in young and older adults.

PubMed

Gaillardin, Florence; Baudry, Stéphane

2018-06-01

This study assessed the influence of attention division, working memory and executive function on stair ascent and descent in young and older adults. Twenty young (25.5 ± 2.1 yrs) and 20 older adults (68.4 ± 5.4 yrs) ascended and descended a 3-step staircase with no simultaneous cognitive task (single-motor task) or while performing a cognitive task (dual-task condition). The cognitive task involved either 1) recalling a word list of the subject's word-span minus 2 words (SPAN-2) to assess the attention division effect, 2) a word list of subject's word-span (SPAN-O) to assess the working memory effect, or 3) recalling in alphabetical order, a word list of the subject's word-span (SPAN-A) to assess the executive function effect. Word-span corresponds to the longest string of words that can be recalled correctly. The duration of ascent and descent of stairs was used to assess the cognitive-motor interaction. Stair ascent and descent duration did not differ between age groups for the single-motor task, and was similar between single-motor task and SPAN-2 in both groups (p > 0.05). In contrast, stair ascent and descent duration increased with SPAN-O compared with SPAN-2 for both groups (p < 0.01). Stair ascent (p = 0.017) and descent (p = 0.008) were longer in SPAN-A than SPAN-O only in older adults. Healthy aging was not associated with a decrease in the capacity to perform motor-cognitive dual tasks that involved ascending and descending of stairs when the cognitive task only required working memory. However, the decrease in dual-task performance involving executive functioning may reflect a subclinical cognitive decline in healthy older adults. Copyright © 2018 Elsevier Inc. All rights reserved.

DETAIL OF ENTRY HALL AND STAIR ON SOUTH SIDE, VIEW ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

DETAIL OF ENTRY HALL AND STAIR ON SOUTH SIDE, VIEW FACING NORTH (with scale stick). - Naval Air Station Barbers Point, Telephone Exchange, Coral Sea Road north of Bismarck Sea Road, Ewa, Honolulu County, HI

1. EAST ELEVATION, SHOWING PENTHOUSE, STAIRS, AND SHED USED TO ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. EAST ELEVATION, SHOWING PENTHOUSE, STAIRS, AND SHED USED TO TREAT HELICOPTER COMPONENTS. SOUTHEAST DOOR TO BUILDING 10 AT RIGHT. - Hughes Aircraft Company, Garage & Maintenance Building, 6775 Centinela Avenue, Los Angeles, Los Angeles County, CA

15. STAIR, NOTE WOODEN WEARING SURFACE ON FLOOR, AND POSITIVELY ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

15. STAIR, NOTE WOODEN WEARING SURFACE ON FLOOR, AND POSITIVELY NO BOYS ALLOWED UPSTAIRS SIGN LOOKING EAST. - W. A. Young & Sons Foundry & Machine Shop, On Water Street along Monongahela River, Rices Landing, Greene County, PA

6. Light tower, detail of stairs leading from first landing ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. Light tower, detail of stairs leading from first landing to cupola, looking east - Baker Island Light, Lightkeeper's House, Just east of Cranberry Isles, at entrance to Frenchman Bay, Bar Harbor, Hancock County, ME

DETAIL ELEVATION VIEW OF EXTERIOR STAIRS ON THE EAST END ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

DETAIL ELEVATION VIEW OF EXTERIOR STAIRS ON THE EAST END OF BUILDING 63, FACING SOUTH. - Naval Computer & Telecommunications Area Station, Enlisted Men's Barracks, West corner of Central Street & Midway Drive, Wahiawa, Honolulu County, HI

7. Historic American Buildings Survey, August, 1966 EXTERIOR STAIR TO ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. Historic American Buildings Survey, August, 1966 EXTERIOR STAIR TO SECOND FLOOR, SHOWING PASSAGE BETWEEN MAIN BLOCK AND REAR ELL. - Andrews-Taylor House, State Route 43, Farm Road 2862 Vicinity, Karnack, Harrison County, TX

13. DETAIL, IRON STAIR RAILING, STREET LEVEL TO GROUND FLOOR ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

13. DETAIL, IRON STAIR RAILING, STREET LEVEL TO GROUND FLOOR LEVEL (2 x 2 negative; 5 x 7 print) - Patent Office Building, Bounded by Seventh, Ninth, F & G Streets, Northwest, Washington, District of Columbia, DC

VIEW OF SOUTHWEST CORNER OF SECOND FLOOR STAIR HALL OF ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW OF SOUTHWEST CORNER OF SECOND FLOOR STAIR HALL OF PAULINE KILKER HOUSE SHOWING ARCHED OPENING IN FOREGROUND, FACING SOUTHWEST. - Pauline Kilker House, 1410 North Lincoln Avenue-3300 West Laurel Street, Tampa, Hillsborough County, FL

VIEW OF NORTH WALL OF SECOND FLOOR STAIR HALL OF ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW OF NORTH WALL OF SECOND FLOOR STAIR HALL OF PAULINE KILKER HOUSE SHOWING DETAIL OF CLOSET DOOR, FACING NORTH. - Pauline Kilker House, 1410 North Lincoln Avenue-3300 West Laurel Street, Tampa, Hillsborough County, FL

12. Interior view of main cabin showing stairs to loft ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

12. Interior view of main cabin showing stairs to loft area, note construction of balcony and roof - Dean E. Call Property, Big Springs Summer Home Area, Lot 5, Block D, Island Park, Fremont County, ID

Musical stairs: the impact of audio feedback during stair-climbing physical therapies for children.

PubMed

Khan, Ajmal; Biddiss, Elaine

2015-05-01

Enhanced biofeedback during rehabilitation therapies has the potential to provide a therapeutic environment optimally designed for neuroplasticity. This study investigates the impact of audio feedback on the achievement of a targeted therapeutic goal, namely, use of reciprocal steps. Stair-climbing therapy sessions conducted with and without audio feedback were compared in a randomized AB/BA cross-over study design. Seventeen children, aged 4-7 years, with various diagnoses participated. Reports from the participants, therapists, and a blinded observer were collected to evaluate achievement of the therapeutic goal, motivation and enjoyment during the therapy sessions. Audio feedback resulted in a 5.7% increase (p = 0.007) in reciprocal steps. Levels of participant enjoyment increased significantly (p = 0.031) and motivation was reported by child participants and therapists to be greater when audio feedback was provided. These positive results indicate that audio feedback may influence the achievement of therapeutic goals and promote enjoyment and motivation in young patients engaged in rehabilitation therapies. This study lays the groundwork for future research to determine the long term effects of audio feedback on functional outcomes of therapy. Stair-climbing is an important mobility skill for promoting independence and activities of daily life and is a key component of rehabilitation therapies for physically disabled children. Provision of audio feedback during stair-climbing therapies for young children may increase their achievement of a targeted therapeutic goal (i.e., use of reciprocal steps). Children's motivation and enjoyment of the stair-climbing therapy was enhanced when audio feedback was provided.

Performance of women with fibromyalgia in walking up stairs while carrying a load

PubMed Central

Adsuar, José C.; Olivares, Pedro R.; Dominguez-Muñoz, Francisco J.; Maestre-Cascales, Cristina; Gusi, Narcis

2016-01-01

Background. Fibromyalgia is a chronic disease characterized by widespread pain and other associated symptoms. It has a relevant impact on physical fitness and the ability to perform daily living tasks. The objective of the study was to analyze the step-by-step-performance and the trunk tilt of women with fibromyalgia in the 10-step stair climbing test compared with healthy controls. Methods. A cross-sectional study was carried out. Twelve women suffering from fibromyalgia and eight healthy controls were recruited from a local association. Participants were asked to climb 10 stairs without carrying a load and 10 stairs carrying a load of 5 kg in each hand. Mediolateral trunk tilt was assessed using the “Functional Assessment of Biomechanics (FAB)” wireless motion capture device, and the time between steps was assessed via weight-bearing insoles. Results. Trunk tilt in the stair-climbing task carrying a load was significantly higher in women with fibromyalgia when compared to the healthy controls (2.31 (0.63) vs. 1.69 (0.51) respectively). The effect of carrying a load was significantly higher for women with fibromyalgia compared with healthy controls at the intermediate and final part of the task. Discussion. Trunk tilt during stair climbing while carrying a load was higher in women with FM, which could increase the risk of falling. Additionally, women with FM experienced a higher pace slowdown as a consequence of the load, which supports the need of including specific strength and resistance training to physical therapies for this population. PMID:26855878

Evidence of compensatory joint kinetics during stair ascent and descent in Parkinson's disease.

PubMed

Conway, Zachary J; Silburn, Peter A; Blackmore, Tim; Cole, Michael H

2017-02-01

Stair ambulation is a challenging activity of daily life that requires larger joint moments than walking. Stabilisation of the body and prevention of lower limb collapse during this task depends upon adequately-sized hip, knee and ankle extensor moments. However, people with Parkinson's disease (PD) often present with strength deficits that may impair their capacity to control the lower limbs and ultimately increase their falls risk. To investigate hip, knee and ankle joint moments during stair ascent and descent and determine the contribution of these joints to the body's support in people with PD. Twelve PD patients and twelve age-matched controls performed stair ascent and descent trials. Data from an instrumented staircase and a three-dimensional motion analysis system were used to derive sagittal hip, knee and ankle moments. Support moment impulses were calculated by summing all extensor moment impulses and the relative contribution of each joint was calculated. Linear mixed model analyses indicated that PD patients walked slower and had a reduced cadence relative to controls. Although support moment impulses were typically not different between groups during stair ascent or descent, a reduced contribution by the ankle joint required an increased knee joint contribution for the PD patients. Despite having poorer knee extensor strength, people with PD rely more heavily on these muscles during stair walking. This adaptation could possibly be driven by the somewhat restricted mobility of this joint, which may provide these individuals with an increased sense of stability during these tasks. Copyright © 2016 Elsevier B.V. All rights reserved.

Age-related differences in dynamic balance control during stair descent and effect of varying step geometry.

PubMed

Novak, A C; Komisar, V; Maki, B E; Fernie, G R

2016-01-01

The incidence of stairway falls and related injuries remains persistently high; however, the risk of stair injuries could be reduced through improved stairway design. The current study investigated dynamic balance control during stair descent and the effects of varying the step geometry. Data were collected from 20 healthy young and 20 older adults as they descended three staircases (riser heights of 7, 7.5 and 8 inches (178, 190 and 203 mm, respectively)). At each riser height, the tread run length was varied between 8 and 14 inches (203 mm and 356 mm) in one-inch (25 mm) increments. Kinematic data provided measures of segmental and whole-body dynamic control. Results demonstrated that older adults had greater lateral tilt of the upper body than young adults, but actually had larger margins of stability than the young in the antero-posterior direction as a result of their slower cadence. Nonetheless, for both age groups, the longer run lengths were found to provide the largest margins of stability. In addition, increase in run length and decrease in riser height tended to reduce forward upper body tilt. These results help to explain the underlying biomechanical factors associated with increased risk of falls and the relationship with step geometry. Considering the importance of stair ambulation in maintaining independence and activity in the community, this study highlights the definite need for safer stair design standards to minimize the risk of falls and increase stair safety across the lifespan. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Kinematic alterations of the lower limbs and pelvis during an ascending stairs task are associated with the degree of knee osteoarthritis severity.

PubMed

Gonçalves, Glaucia Helena; Selistre, Luiz Fernando Approbato; Petrella, Marina; Mattiello, Stela Márcia

2017-03-01

Individuals with knee osteoarthritis (OA) generally demonstrate great difficulty in ascending stairs. The strategies and compensations used by these individuals in stair activities have not been fully established. The purpose of this study was to investigate the joint kinematics of the pelvis, hip, knee and ankle throughout the gait cycle, in the sagittal and frontal planes, in individuals with mild and moderate knee OA, during an ascending stairs task. Thirty-one individuals with knee OA and 19 controls were subjected to clinical and radiographic analysis, divided into three groups: control, mild knee OA, and moderate knee OA. Participants answered a self-reported questionnaire, carried out performance-based tests, and their kinematic data were recorded during an ascending stairs task using an eight-camera Qualisys 3D-Motion analysis system. The individuals with moderate degrees of knee OA demonstrated kinematic alterations in the pelvis, hip, knee, and ankle in the sagittal plane. The individuals with mild degrees of knee OA demonstrated kinematic alterations of the hip in the frontal plane, and kinematic alterations of the ankle in the sagittal plane. The ascending stairs task allowed verification of meaningful information regarding gait strategies used by individuals with mild and moderate knee OA. The strategies of these two groups of individuals are different for this task, although more pronounced in individuals with moderate knee OA. The findings should be taken into account in the development of rehabilitation programs. Copyright © 2017 Elsevier B.V. All rights reserved.

36. OVERALL VIEW OF PATTERN SHOP FORM TOP OF STAIR, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

36. OVERALL VIEW OF PATTERN SHOP FORM TOP OF STAIR, SHEET METAL AREA AND OFFICE IN FOREGROUND-LOOKING WEST. - W. A. Young & Sons Foundry & Machine Shop, On Water Street along Monongahela River, Rices Landing, Greene County, PA

36. Basement, cellar beneath main stairway, with skylight in stair ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

36. Basement, cellar beneath main stairway, with skylight in stair riser, and adjacent storage room, view to east - Portsmouth Naval Hospital, Hospital Building, Rixey Place, bounded by Williamson Drive, Holcomb Road, & The Circle, Portsmouth, Portsmouth, VA

Shallow Water Propagation

DTIC Science & Technology

2014-09-30

improvements in single-scattering treatments at stair-step risers in approximations for range dependence; non-uniform depth gridding to treat thin layers...turns out for such problems that preserving accuracy requires conceptually splitting a stair- riser interface into two interfaces separated by a very

6. VIEW OF LAUNCHER BUILDING 28402 SHOWING STEEL STAIRS LEADING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. VIEW OF LAUNCHER BUILDING 28402 SHOWING STEEL STAIRS LEADING UP TO LAUNCH DECK; VIEW TO NORTHWEST. - Cape Canaveral Air Station, Launch Complex 17, Facility 28402, East end of Lighthouse Road, Cape Canaveral, Brevard County, FL

Mirror, Mirror by the Stairs: The Impact of Mirror Exposure on Stair versus Elevator Use in College Students

PubMed Central

Hodgin, Katie L.; Graham, Dan J.

2016-01-01

Previous research has indicated that self-awareness-inducing mirrors can successfully incite behaviors that align with one’s personal values, such as helping others. Other research has found a large discrepancy between the high percentage of young adults who report valuing the healthfulness of physical activity (PA) and the low percentage who actually meet PA participation standards. However, few studies have examined how mirror exposure and both perceived and actual body size influence highly valued PA participation among college students. The present study assessed stair versus elevator use on a western college campus and hypothesized that mirror exposure would increase the more personally healthy transportation method of stair use. In accordance with previous research, it was also hypothesized that males and those with a lower body mass index (BMI) would be more likely to take the stairs, and that body size distorting mirrors would impact the stair–elevator decision. One hundred sixty-seven students (51% male) enrolled in an introductory psychology course were recruited to take a survey about their “transportation choices” at an indoor campus parking garage. Participants were individually exposed to either no mirror, a standard full-length mirror, or a full-length mirror manipulated to make the reflected body size appear either slightly thinner or slightly wider than normal before being asked to go to the fourth floor of the garage for a survey. Participants’ choice of floor-climbing method (stairs or elevator) was recorded, and they were administered an Internet-based survey assessing demographic information, BMI, self-awareness, perceived body size, and other variables likely to be associated with stair use. Results from logistic regression analyses revealed that participants who were not exposed to a mirror [odds ratios (OR) = 0.37, 95% CI: 0.14–0.96], males (OR = 0.33, 95% CI: 0.13–0.85), those with lower BMI (OR = 0.84, 95% CI: 0.71–0.99), those with higher exercise participation (OR = 1.09, 95% CI: 1.02–1.18), and those engaging in more unhealthy weight-control behaviors (OR = 1.55, 95% CI: 1.14–2.11) showed increased odds of taking the stairs. Implications and future directions are discussed. PMID:27200333

34. VAL, DETAIL OF STAIRS ON COUNTERWEIGHT SLAB WITH COUNTERWEIGHT ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

34. VAL, DETAIL OF STAIRS ON COUNTERWEIGHT SLAB WITH COUNTERWEIGHT CAR RAILS ON RIGHT AND PERSONNEL CAR RAILS ON LEFT. - Variable Angle Launcher Complex, Variable Angle Launcher, CA State Highway 39 at Morris Reservior, Azusa, Los Angeles County, CA

Detail of west corner of front entry stair showing mission ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Detail of west corner of front entry stair showing mission scrolls and sill of former living porch opening, facing east. - Albrook Air Force Station, Company Officer's Quarters, East side of Canfield Avenue, Balboa, Former Panama Canal Zone, CZ

46. DETAILS OF PLATFORMS & STAIRS, Y&D No. 107724 Scales ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

46. DETAILS OF PLATFORMS & STAIRS, Y&D No. 107724 Scales 3/4' = 1' and as indicated; July 2, 1929 - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT

14. DETAIL, IRON STAIR RAILING, STREET LEVEL TO GROUND FLOOR ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

14. DETAIL, IRON STAIR RAILING, STREET LEVEL TO GROUND FLOOR LEVEL, SHOWING NEWEL POST (2 x 2 negative; 5 x 7 print) - Patent Office Building, Bounded by Seventh, Ninth, F & G Streets, Northwest, Washington, District of Columbia, DC

Room 202, a small laboratory between the west stairs on ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Room 202, a small laboratory between the west stairs on the left, and faculty offices to the right. View to north. - San Bernardino Valley College, Life Science Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

View shows stairs to second floor machine shop and belts ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

View shows stairs to second floor machine shop and belts from main shaft going down into basement where they power machinery for elevator. - Thomas A. Edison Laboratories, Building No. 5, Main Street & Lakeside Avenue, West Orange, Essex County, NJ

INTERIOR DETAIL, WINDOW OPENING ONTO THE SERVICE STAIR FROM DINING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

INTERIOR DETAIL, WINDOW OPENING ONTO THE SERVICE STAIR FROM DINING ROOM PASSAGE. OPENINGS LIKE THESE ARE PRESENT IN A NUMBER OF PLACES, “BORROWING LIGHT” FOR OTHERWISE DARK INTERIOR SPACES - The Woodlands, 4000 Woodlands Avenue, Philadelphia, Philadelphia County, PA

Promotion of Physical Activity Using Point-of-Decision Prompts in Berlin Underground Stations

PubMed Central

Müller-Riemenschneider, Falk; Nocon, Marc; Reinhold, Thomas; Willich, Stefan N.

2010-01-01

To evaluate point-of-decision prompts in the promotion of stair use in Germany, motivational posters were placed at three underground stations in Berlin. The proportion of passengers using stairs or stairways was counted before, during installation, and two weeks after removal of posters. In total, 5,467 passersby were counted. Stair use increased significantly in women, but not in men. The present pilot study thereby shows that the use of point-of-decision prompts is also feasible in Germany and it provides some evidence of effectiveness. Methodologically rigorous studies are warranted to confirm these findings. PMID:20948947

Association between body composition and stair negotiation ability among individuals >55 years of age: a cross-sectional study

PubMed Central

Dip, Renata Maciulis; Cabrera, Marcos AS; Prato, Sabrina Ferrari

2017-01-01

Background Loss of muscle strength exerts a considerable impact on the quality of life and mortality of older adults. The present household survey study measured body composition and muscle strength with the aim of analyzing the roles of low lean mass, low muscle strength and obesity in stair negotiation ability and the effect of comorbidities on the relationship between body composition and functional capacity. Methods Body composition was assessed using bioelectrical impedance analysis and muscle strength was assessed with a hand grip dynamometer. The study population comprised individuals >55 years of age from a medium-sized Brazilian municipality. The sample included 451 participants. Results A total of 368 subjects were interviewed; their ages varied from 56 to 91 years. Among males, low muscle strength was associated with stair negotiation difficulty independent of muscle mass, age and obesity but muscle mass was not. However, when we analyzed comorbidities and body composition jointly, chronic lower limb pain and obesity were independently associated with stair negotiation difficulty but body composition and age were not. Among women, after comorbidities were included into the model, low muscle strength and obesity remained associated with stair negotiation difficulty as chronic lower limb pain and depression. The relationship between muscle function and comorbidities is discussed in this article. PMID:28860730

Association between body composition and stair negotiation ability among individuals >55 years of age: a cross-sectional study.

PubMed

Dip, Renata Maciulis; Cabrera, Marcos As; Prato, Sabrina Ferrari

2017-01-01

Loss of muscle strength exerts a considerable impact on the quality of life and mortality of older adults. The present household survey study measured body composition and muscle strength with the aim of analyzing the roles of low lean mass, low muscle strength and obesity in stair negotiation ability and the effect of comorbidities on the relationship between body composition and functional capacity. Body composition was assessed using bioelectrical impedance analysis and muscle strength was assessed with a hand grip dynamometer. The study population comprised individuals >55 years of age from a medium-sized Brazilian municipality. The sample included 451 participants. A total of 368 subjects were interviewed; their ages varied from 56 to 91 years. Among males, low muscle strength was associated with stair negotiation difficulty independent of muscle mass, age and obesity but muscle mass was not. However, when we analyzed comorbidities and body composition jointly, chronic lower limb pain and obesity were independently associated with stair negotiation difficulty but body composition and age were not. Among women, after comorbidities were included into the model, low muscle strength and obesity remained associated with stair negotiation difficulty as chronic lower limb pain and depression. The relationship between muscle function and comorbidities is discussed in this article.

Enhancing the Trajectory Generation of a Stair-Climbing Mobility System

PubMed Central

Chocoteco, Jose Abel

2017-01-01

Recent advances in mobile robotic technologies have enabled significant progress to be made in the development of Stair-Climbing Mobility Systems (SCMSs) for people with mobility impairments and limitations. These devices are mainly characterized by their ability to negotiate those architectural barriers associated with climbing stairs (curbs, ramps, etc.). The development of advanced trajectory generators with which to surpass such architectural barriers is one of the most important aspects of SCMSs that has not yet been appropriately exploited. These advanced trajectory generators have a considerable influence on the time invested in the stair climbing process and on passenger comfort and, consequently, provide people with physical disabilities with greater independence and a higher quality of life. In this paper, we propose a new nonlinear trajectory generator for an SCMS. This generator balances the stair-climbing time and the user’s comfort and includes the most important constraints inherent to the system behavior: the geometry of the architectural barrier, the reconfigurable nature of the SCMS (discontinuous states), SCMS state-transition diagrams, comfort restrictions and physical limitations as regards the actuators, speed and acceleration. The SCMS was tested on a real two-step staircase using different time-comfort combinations and different climbing strategies to verify the effectiveness and the robustness of the proposed approach.

Gender difference in older adult's utilization of gravitational and ground reaction force in regulation of angular momentum during stair descent.

PubMed

Singhal, Kunal; Kim, Jemin; Casebolt, Jeffrey; Lee, Sangwoo; Han, Ki-Hoon; Kwon, Young-Hoo

2015-06-01

Angular momentum of the body is a highly controlled quantity signifying stability, therefore, it is essential to understand its regulation during stair descent. The purpose of this study was to investigate how older adults use gravity and ground reaction force to regulate the angular momentum of the body during stair descent. A total of 28 participants (12 male and 16 female; 68.5 years and 69.0 years of mean age respectively) performed stair descent from a level walk in a step-over-step manner at a self-selected speed over a custom made three-step staircase with embedded force plates. Kinematic and force data were used to calculate angular momentum, gravitational moment, and ground reaction force moment about the stance foot center of pressure. Women show a significantly greater change in normalized angular momentum (0.92Nms/Kgm; p=.004) as compared to men (0.45Nms/Kgm). Women produce higher normalized GRF (p=.031) during the double support phase. The angular momentum changes show largest backward regulation for Step 0 and forward regulation for Step 2. This greater difference in overall change in the angular momentum in women may explain their increased risk of fall over the stairs. Copyright © 2015 Elsevier B.V. All rights reserved.

Noninvasive EEG correlates of overground and stair walking.

PubMed

Brantley, Justin A; Luu, Trieu Phat; Ozdemir, Recep; Zhu, Fangshi; Winslow, Anna T; Huang, Helen; Contreras-Vidal, Jose L

2016-08-01

Automated walking intention detection remains a challenge in lower-limb neuroprosthetic systems. Here, we assess the feasibility of extracting motor intent from scalp electroencephalography (EEG). First, we evaluated the corticomuscular coherence between central EEG electrodes (C1, Cz, C2) and muscles of the shank and thigh during walking on level ground and stairs. Second, we trained decoders to predict the linear envelope of the surface electromyogram (EMG). We observed significant EEG-led corticomuscular coupling between electrodes and sEMG (tibialis anterior) in the high delta (3-4 Hz) and low theta (4-5 Hz) frequency bands during level walking, indicating efferent signaling from the cortex to peripheral motor neurons. The coherence was increased between EEG and vastus lateralis and tibialis anterior in the delta band (<; 2 Hz) during stair ascent, indicating a task specific modulation in corticomuscular coupling. However, EMG was the leading signal for biceps femoris and gastrocnemius coherence during stair ascent, possibly representing afferent feedback loops from periphery to the motor cortex. Decoder validation showed that EEG signals contained information about the sEMG patterns during over ground walking, however, the accuracy of the predicted sEMG patterns decreased during the stair condition. Overall, these initial findings support the feasibility of integrating sEMG and EEG into a hybrid decoder for volitional control of lower limb neuroprostheses.

Stair and entry room, bunkhouse, first floor interior. Door from ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Stair and entry room, bunkhouse, first floor interior. Door from entry hall leads to toilets and bathing rooms. A coat and hat rack is on each side of the door. - Sespe Ranch, Bunkhouse, 2896 Telegraph Road, Fillmore, Ventura County, CA

Effects of obesity on the biomechanics of stair-walking in children.

PubMed

Strutzenberger, G; Richter, A; Schneider, M; Mündermann, A; Schwameder, H

2011-05-01

Anthropometric characteristics, particularly body mass, are important factors in the development and progression of varus/valgus angular deformities of the knee and have long-term implications including increased risk of osteoarthritis. However, information on how excessive body weight affects the biomechanics of dynamic activities in children is limited. The purpose of this study was to test the hypothesis that during stair-walking lower extremity joint moments normalized to body mass in obese children are greater than those in normal-weight children. Eighteen obese children (10.5±1.5 years, 148±10cm, 56.6±8.4kg) and 17 normal-weight children (10.4±1.3 years, 143±9cm, 36.7±7.5kg) were recruited. A Vicon system and two AMTI force plates were used to record and analyze the kinematics and kinetics of ascending and descending stairs. Significant differences in spatio-temporal, kinematic and kinetic parameters during ascending and descending stairs between obese and normal-weight children were detected. For stair ascent, greater hip abduction moments (+23%; p=0.001) and greater knee extension moments (+20%; p=0.008) were observed. For stair descent, smaller hip extension moment (-52%; p=0.031), and greater hip flexion moments (+25%; p=0.016) and knee extension moments (+15%, p=0.008) were observed for obese subjects. To date, it is unclear if and how the body may adapt to greater joint moments in obese children. Nevertheless, these differences in joint moments may contribute to a cumulative overloading of the joint through adolescence into adulthood, and potentially result in a greater risk of developing knee and hip osteoarthritis. Copyright © 2011 Elsevier B.V. All rights reserved.

Knee strength, power and stair performance of the elderly 5 years after unicompartmental knee arthroplasty.

PubMed

Li, Yumeng; Kakar, Rumit S; Fu, Yang-Chieh; Mahoney, Ormonde M; Kinsey, Tracy L; Simpson, Kathy J

2018-04-13

Unicompartmental knee arthroplasty (UKA) has been shown to demonstrate some satisfactory short-term outcomes. However, to our knowledge, there have been no reports on midterm or long-term knee extensor strength and leg extensor power post-UKA. Therefore, the purposes of this study were: (1) to assess the isokinetic knee extensor strength, leg extensor power and stair performance of elderly participants at 5 years UKA post-operation; (2) to compare the differences in knee extensor strength and leg extensor power between the UKA and contralateral healthy limbs. Nineteen elderly participants (75 ± 5 years) who had a medial or a lateral compartment UKA at 5 years post-operation were recruited. The isokinetic knee extensor strength and leg extensor power were measured. The stair performance was tested on a 4-step stair, and ascent and descent velocities were calculated. The pain level was assessed. The UKA limbs' knee extensor strength and leg extensor power were 1.01 ± 0.39 Nm/kg and 0.98 ± 0.27 W/kg, respectively. The stair ascent and descent velocities were 0.37 ± 0.07 and 0.38 ± 0.11 m/s, respectively. In addition, the UKA limbs exhibited comparable knee strength and leg power relative to the contralateral limbs. In general, the knee extensor strength and leg extensor power exhibited by the UKA limbs at 5 years post-operation may be typical in comparison with the normative data. We suggest that UKA is a satisfactory treatment in regard to the recovery of knee strength, leg power and ability to climb up and down stairs.

Quantifying stair gait stability in young and older adults, with modifications to insole hardness.

PubMed

Antonio, Patrick J; Perry, Stephen D

2014-07-01

Stair gait falls are prevalent in older adults aged 65 years and older. Extrinsic variables such as changes to insole hardness are important factors that can compromise the balance control system and increase the incidence of falls, especially since age-related decline in the cutaneous sensation is common. Balance measurements such as the minimum center of mass/base of support (COM-BOS, termed 'stability margin') and COM-BOS medial/lateral range provide information about stability during stair gait. This study was conducted to investigate stair gait stability of young and older adults, with modifications to insole hardness. Twenty healthy adults (10 young adults, 10 older adults) were recruited (mean age = 23.1, SD 2.1; mean age = 73.2, SD 5.5) and instructed to descend a 4 step staircase, for a total of 40 trials. All participants wore similar canvas shoes of varying sizes, and corresponding insole hardnesses (barefoot, soft, medium, hard). Kinematic equipment utilized 12 infrared markers anteriorly placed on the individual to record COM motion and BOS location. The findings from the study demonstrated that older adults were less stable during stair descent. Consequently, insole conditions revealed that the barefoot condition may increase the likelihood of falls, as opposed to the other insole hardnesses (soft, medium and hard). These results suggest that older adults while barefoot are putting themselves at a great risk of falling during stair descent. Since age-related changes are inevitable and the preferred footwear of choice inside the home is bare feet, this is a crucial issue that should be addressed. Copyright © 2014 Elsevier B.V. All rights reserved.

Correlates of physical function among stroke survivors: an examination of the 2015 BRFSS.

PubMed

Ilunga Tshiswaka, D; Seals, S R; Raghavan, P

2018-02-01

To identify the characteristics of stroke survivors with poor physical function. Cross-sectional. Secondary data analyses were performed with the 2015 Behavioral Risk Factor Surveillance System data set. Unadjusted and adjusted logistic regressions were employed to determine the correlates of poor physical function in stroke survivors. Self-reported difficulty with walking and stairs was used as a proxy for physical function. Characteristics such as age, race, sex, difficulty doing errands alone, difficult dressing or bathing alone, health care coverage, time since last routine checkup, and reported financial difficulty with regard to health care access were examined as contributing factors to physical function. Approximately half of all stroke survivors reported having difficulty with walking and stairs (50.3%). As expected, the odds of reporting difficulty with walking and stairs were higher among stroke survivors aged 40 years and above (p < 0.0001). Interestingly, black/African American and multiracial respondents had higher odds of reporting difficulty with walking and stairs than whites, whereas Hispanic respondents had lower odds of reporting difficulty with walking and stairs than whites (p < 0.0001). Further analyses revealed that the disparity of physical function was preserved (p < 0.0001) after adjusting for age, race, sex, education level, family income, marital status, employment status, health insurance status, affordability of healthcare, and length of time from last doctor's visit. There were racial/ethnic disparities in physical function. Specifically, blacks/ African Americans had a 5.6% increase in the odds of reporting difficulty with walking and stairs than whites. Moreover, Hispanics reported significantly fewer problems than whites. Overall, similar sociocultural patterns in non-stroke and stroke populations were observed in this study. Copyright © 2017 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

Variations in plantar pressure variables across five cardiovascular exercises.

PubMed

Burnfield, Judith M; Jorde, Amy G; Augustin, Tanner R; Augustin, Tate A; Bashford, Gregory R

2007-11-01

To quantify variations in plantar pressure variables in healthy adults across five cardiovascular exercises. Ten young (19-35 yr old) and 10 middle-aged (45-60 yr old) individuals participated. After equipment familiarization, plantar pressure data were recorded during walking, running, elliptical training, stair climbing, and recumbent biking. Separate one-way analyses of variance with repeated measures identified significant differences in pressure variables across exercises and between age groups under the forefoot, arch, and heel. Forefoot: Peak pressures were higher during walking (253 kPa), running (251 kPa), and elliptical training (213 kPa) than stair climbing (130 kPa) and recumbent biking (41 kPa; P < or = 0.001). Biking pressures were lower than all other conditions (P < 0.001). Arch: Pressures were higher during running (144 kPa) compared with all other conditions (P < or = 0.001). Intermediate-level pressures during walking (119 kPa) and elliptical training (102 kPa) exceeded those during stair climbing (80 kPa; P < or = 0.002). Pressures were lowest during recumbent biking (33 kPa; P < 0.001). Heel: Pressures were highest during walking (215 kPa) and running (188 kPa), exceeding those recorded during all other activities (P < 0.001). Moderate elliptical training pressures (94 kPa) surpassed stair climbing values (66 kPa; P = 0.014). Pressures were lowest during recumbent biking (25 kPa; P < 0.001). The only significant difference identified between age groups was a larger arch contact area in the young compared with middle-aged, when averaged across exercises (P = 0.011). When protection of the forefoot is important (e.g., diabetic foot neuropathies), biking and stair climbing offer optimal pressure reductions. If protecting the heel from high pressures and forces is warranted, recumbent biking, stair climbing, and elliptical training provide greater relief.

42. INTERIOR, FIRST FLOOR, NORTHWEST CORNER OF GRAND STAIRCASE (STAIRS ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

42. INTERIOR, FIRST FLOOR, NORTHWEST CORNER OF GRAND STAIRCASE (STAIRS G), SIDE AISLE, WEST WALL, THE NEGRO'S CONTRIBUTION IN THE SOCIAL AND CULTURAL DEVELOPMENT OF AMERICA: SCIENCE MURAL - U.S. Department of the Interior, Eighteenth & C Streets Northwest, Washington, District of Columbia, DC

37. Closeup of stairs in previous photo, leading up to ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

37. Close-up of stairs in previous photo, leading up to El Macho and down to Plaza de Armas, from Santa Barbara Bastion, viewed from northwest - Castillo de San Felipe del Morro, Northwest end of San Juan, San Juan, San Juan Municipio, PR

45. INTERIOR, FIRST FLOOR, SOUTHEAST CORNER OF GRAND STAIRCASE (STAIRS ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

45. INTERIOR, FIRST FLOOR, SOUTHEAST CORNER OF GRAND STAIRCASE (STAIRS G), SIDE AISLE, EAST WALL, THE NEGRO'S CONTRIBUTION IN THE SOCIAL AND CULTURAL DEVELOPMENT OF AMERICA: EDUCATION MURAL - U.S. Department of the Interior, Eighteenth & C Streets Northwest, Washington, District of Columbia, DC

Battery Carpenter Observation Station, view down from tower stair landing ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Battery Carpenter Observation Station, view down from tower stair landing on west side; view northwest - Fort McKinley, Battery Carpenter Observation Station, West side of East Side Drive, approximately 275 feet south of Weymouth Way, Great Diamond Island, Portland, Cumberland County, ME

INTERIOR VIEW OF THE ENTRY HALL AND STAIRS TO SECOND ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

INTERIOR VIEW OF THE ENTRY HALL AND STAIRS TO SECOND FLOOR. TAKEN FROM THE DINING ROOM. NOTE THE TONGUE-AND-GROOVE WOOD FLOORING AND THE TELEPHONE NICHE. VIEW FACING NORTHWEST. - Hickam Field, Officers' Housing Type L, 702 Julian Avenue, Honolulu, Honolulu County, HI

22. Float located adjacent to entry stair in filtration bed. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

22. Float located adjacent to entry stair in filtration bed. The float actuates a valve that maintains water level over the bed. - Lake Whitney Water Filtration Plant, Filtration Plant, South side of Armory Street between Edgehill Road & Whitney Avenue, Hamden, New Haven County, CT

INTERIOR VIEW, WEST CHAMBER OVER THE SALOON FROM THE EAST. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

INTERIOR VIEW, WEST CHAMBER OVER THE SALOON FROM THE EAST. THE SIX-PANEL DOOR VISIBLE IN THE MAIN PASSAGE OPENS ONTO THE ATTIC STAIRS. THE SERVICE STAIR DOES NOT EXTEND CONTINUOUSLY FROM CELLAR TO ATTIC - The Woodlands, 4000 Woodlands Avenue, Philadelphia, Philadelphia County, PA

INTERIOR DETAIL, DINING ROOM PASSAGE AND SERVICE STAIR. THE VISIBLE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

INTERIOR DETAIL, DINING ROOM PASSAGE AND SERVICE STAIR. THE VISIBLE RETRACTABLE DOOR PANEL AND ITS OPPOSING MATE, NOT VISIBLE IN THE PHOTOGRAPH, COULD BE CLOSED IN ORDER TO CREATE A DISCRETE STAGING AREA FOR SERVICE FUNCTIONS - The Woodlands, 4000 Woodlands Avenue, Philadelphia, Philadelphia County, PA

30. VAL LOOKING DOWN THE LAUNCHER SLAB STAIRS AT THE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

30. VAL LOOKING DOWN THE LAUNCHER SLAB STAIRS AT THE PROJECTILE LOADING CAR AND LOADING PLATFORM ADJACENT TO THE PROJECTILE LOADING DECK AND LAUNCHER BRIDGE. - Variable Angle Launcher Complex, Variable Angle Launcher, CA State Highway 39 at Morris Reservior, Azusa, Los Angeles County, CA

43. INTERIOR, FIRST FLOOR, SOUTHWEST CORNER OF GRAND STAIRCASE (STAIRS ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

43. INTERIOR, FIRST FLOOR, SOUTHWEST CORNER OF GRAND STAIRCASE (STAIRS G), SIDE AISLE, WEST WALL, THE NEGRO'S CONTRIBUTION IN THE SOCIAL AND CULTURAL DEVELOPMENT OF AMERICA: THE ARTS MURAL - U.S. Department of the Interior, Eighteenth & C Streets Northwest, Washington, District of Columbia, DC

Robot-assisted practice of gait and stair climbing in nonambulatory stroke patients.

PubMed

Hesse, Stefan; Tomelleri, Christopher; Bardeleben, Anita; Werner, Cordula; Waldner, Andreas

2012-01-01

A novel gait robot enabled nonambulatory patients the repetitive practice of gait and stair climbing. Thirty nonambulatory patients with subacute stroke were allocated to two groups. During 60 min sessions every workday for 4 weeks, the experimental group received 30 min of robot training and 30 min of physiotherapy and the control group received 60 min of physiotherapy. The primary variable was gait and stair climbing ability (Functional Ambulation Categories [FAC] score 0-5); secondary variables were gait velocity, Rivermead Mobility Index (RMI), and leg strength and tone blindly assessed at onset, intervention end, and follow-up. Both groups were comparable at onset and functionally improved over time. The improvements were significantly larger in the experimental group with respect to the FAC, RMI, velocity, and leg strength during the intervention. The FAC gains (mean +/- standard deviation) were 2.4 +/- 1.2 (experimental group) and 1.2 +/- 1.5 (control group), p = 0.01. At the end of the intervention, seven experimental group patients and one control group patient had reached an FAC score of 5, indicating an ability to climb up and down one flight of stairs. At follow-up, this superior gait ability persisted. In conclusion, the therapy on the novel gait robot resulted in a superior gait and stair climbing ability in nonambulatory patients with subacute stroke; a higher training intensity was the most likely explanation. A large randomized controlled trial should follow.

Kinetic comparison of older men and women during walk-to-stair descent transition.

PubMed

Singhal, Kunal; Kim, Jemin; Casebolt, Jeffrey; Lee, Sangwoo; Han, Ki Hoon; Kwon, Young-Hoo

2014-09-01

Stair walking is one of the most challenging tasks for older adults, with women reporting higher incidence of falls. The purpose of this study was to investigate the gender differences in kinetics during stair descent transition. Twenty-eight participants (12 male and 16 female; 68.5 and 69.0 years of mean age, respectively) performed stair descent from level walking in a step-over-step manner at a self-selected speed over a custom-made three-step staircase with embedded force plates. Kinematic and force data were combined using inverse dynamics to generate kinetic data for gender comparison. The top and the first step on the staircase were chosen for analysis. Women showed a higher trail leg peak hip abductor moment (-1.0 Nm/kg), lower trail leg peak knee extensor moment and eccentric power (0.74 Nm/kg and 3.15 W/kg), and lower peak concentric power at trail leg ankle joint (1.29 W/kg) as compared to men (p<0.05; -0.82 Nm/kg, 0.89 Nm/kg, 3.83 W/kg, and 1.78 W/kg, respectively). The lead leg knee eccentric power was also lower in women (p<0.05). This decreased ability to exert knee control during stair descent transition may predispose women to a higher risk of fall. Copyright © 2014 Elsevier B.V. All rights reserved.

The BIOSIS data base: Evaluation of its indexes and the STRATBLDR, CHEMFILE, STAIRS and DIALOG systems for on-line searching

NASA Technical Reports Server (NTRS)

Nees, M.; Green, H. O.

1977-01-01

An IBM-developed program, STAIRS, was selected for performing a search on the BIOSIS file. The evaluation of the hardware and search systems and the strategies used are discussed. The searches are analyzed by type of end user.

FACILITY 89. INTERIOR OF ENTRY AND STAIR, WITH DINING ROOM ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

FACILITY 89. INTERIOR OF ENTRY AND STAIR, WITH DINING ROOM TO LEFT, AS SEEN FROM LIVING ROOM. VIEW FACING SOUTHEAST. - U.S. Naval Base, Pearl Harbor, Naval Housing Area Makalapa, Junior Officers' Quarters Type K, Makin Place, & Halawa, Makalapa, & Midway Drives, Pearl City, Honolulu County, HI

78 FR 39649 - Physical Medicine Devices; Reclassification of Stair-Climbing Wheelchairs; Correction

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-02

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration 21 CFR Part 890 [Docket No. FDA-2013-N-0568] Physical Medicine Devices; Reclassification of Stair-Climbing Wheelchairs; Correction AGENCY: Food and Drug Administration, HHS. ACTION: Proposed order; correction. SUMMARY: The Food and Drug...

Culturally Responsive Teaching: The Harlem Renaissance in an Urban English Class

ERIC Educational Resources Information Center

Stairs, Andrea J.

2007-01-01

Andrea J. Stairs advocates culturally responsive teaching, a practice that explicitly highlights "issues of race, ethnicity, and culture as central to teaching, learning, and schooling," and emphasizes the necessity of interrogating the themes of race, power, and privilege in the urban classroom. Stairs observes two student teachers as…

29 CFR 1926.1052 - Stairways.

Code of Federal Regulations, 2011 CFR

2011-07-01

...° from horizontal. (3) Riser height and tread depth shall be uniform within each flight of stairs, including any foundation structure used as one or more treads of the stairs. Variations in riser height or... having four or more risers or rising more than 30 inches (76 cm), whichever is less, shall be equipped...

29 CFR 1926.1052 - Stairways.

Code of Federal Regulations, 2012 CFR

2012-07-01

...° from horizontal. (3) Riser height and tread depth shall be uniform within each flight of stairs, including any foundation structure used as one or more treads of the stairs. Variations in riser height or... having four or more risers or rising more than 30 inches (76 cm), whichever is less, shall be equipped...

29 CFR 1926.1052 - Stairways.

Code of Federal Regulations, 2010 CFR

2010-07-01

...° from horizontal. (3) Riser height and tread depth shall be uniform within each flight of stairs, including any foundation structure used as one or more treads of the stairs. Variations in riser height or... having four or more risers or rising more than 30 inches (76 cm), whichever is less, shall be equipped...

29 CFR 1926.1052 - Stairways.

Code of Federal Regulations, 2013 CFR

2013-07-01

...° from horizontal. (3) Riser height and tread depth shall be uniform within each flight of stairs, including any foundation structure used as one or more treads of the stairs. Variations in riser height or... having four or more risers or rising more than 30 inches (76 cm), whichever is less, shall be equipped...

29 CFR 1926.1052 - Stairways.

Code of Federal Regulations, 2014 CFR

2014-07-01

...° from horizontal. (3) Riser height and tread depth shall be uniform within each flight of stairs, including any foundation structure used as one or more treads of the stairs. Variations in riser height or... having four or more risers or rising more than 30 inches (76 cm), whichever is less, shall be equipped...

Motivational Signage Increases Physical Activity on a College Campus

ERIC Educational Resources Information Center

Ford, M. Allison; Torok, Donald

2008-01-01

Objective: The authors evaluated whether motivational signage influenced rates of stair use relative to elevator use on a college campus. Participants: In March and April 2004, the authors observed students, faculty, staff, and any visitors accessing a college campus building. Methods: During Phase I, the authors monitored ascending stair and…

StairStepper: An Adaptive Remedial iSTART Module

ERIC Educational Resources Information Center

Perret, Cecile A.; Johnson, Amy M.; McCarthy, Kathryn S.; Guerrero, Tricia A.; Dai, Jianmin; McNamara, Danielle S.

2017-01-01

This paper introduces StairStepper, a new addition to Interactive Strategy Training for Active Reading and Thinking (iSTART), an intelligent tutoring system (ITS) that provides adaptive self-explanation training and practice. Whereas iSTART focuses on improving comprehension at levels geared toward answering challenging questions associated with…

46. Historic American Buildings Survey L. C. Durette, Photographer CHIMNEY ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

46. Historic American Buildings Survey L. C. Durette, Photographer CHIMNEY BASE LOOKING N.E. NOTE ORIGINAL HEWN TIMBER FRAMING THE STAIR, AND BEHIND IT A LATER SAWN TIMBER FOR PRESENT STAIR. BRICK UNDERPINNING OF CELLAR WALL COMPARATIVELY RECENT. - Doe Garrison, Lamprey River & Great Bay, Newmarket, Rockingham County, NH

Taken from ell into house, northeast looking southwest. Original back ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Taken from ell into house, northeast looking southwest. Original back stairs (now have a floor covering the opening at the top), board and batten door at base of old stairs, and closed off fireplaces behind radiators on both left and right. - Samuel P. Grindle House, 13 School Street, Castine, Hancock County, ME

6. VIEW DESCENDING THE NORTH STAIRS OF THE HEADWALL, LEADING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. VIEW DESCENDING THE NORTH STAIRS OF THE HEADWALL, LEADING FROM THE EAST END OF FORECOURT TERRACE LEVEL TO THE LOWER LEVEL, AND DIRECTLY ONTO THE RADIAL PAVING OF COLORED MARBLE COBBLES ARRANGED TO REPRESENT THE TWELVE SIGNS OF THE ZODIAC - Kykuit, 200 Lake Road, Pocantico Hills, Westchester County, NY

Stair Types and Mathematics, Carpentry: 901896.

ERIC Educational Resources Information Center

Dade County Public Schools, Miami, FL.

The curriculum guide outlines a course for grades 11 and 12 designed to provide instruction in the layout and construction of various types of stairs. Students completing the course will be expected to have skills and knowledge of building construction plans, concrete forms, walls, roofs and doors, in addition to a basic knowledge of mathematics…

61. View of TR spiral access stair system from transmitter ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

61. View of TR spiral access stair system from transmitter building no. 102 mezzanine level; note elevator door on right. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

VIEW OF WIDE STAIR TO SECOND FLOOR FROM GROUND FLOOR. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW OF WIDE STAIR TO SECOND FLOOR FROM GROUND FLOOR. VIEW FACING SOUTH - U.S. Naval Base, Pearl Harbor, Ford Island Polaris Missile Lab & U.S. Fleet Ballistic Missile Submarine Training Center, Between Lexington Boulvevard and the sea plane ramps on the southwest side of Ford Island, Pearl City, Honolulu County, HI

46 CFR 116.438 - Stairtowers, stairways, ladders, and elevators.

Code of Federal Regulations, 2012 CFR

2012-10-01

... landings of all stairways shall be composed of steel, and risers must be of approved incombustible material... of riser of stairs in different flights of stairs in a stairway or stairtower must be minimized. In... riser shall not have a variance exceeding 5 millimeters (0.19685 inches). (h) In a stairway or...

46 CFR 116.438 - Stairtowers, stairways, ladders, and elevators.

Code of Federal Regulations, 2011 CFR

2011-10-01

... landings of all stairways shall be composed of steel, and risers must be of approved incombustible material... of riser of stairs in different flights of stairs in a stairway or stairtower must be minimized. In... riser shall not have a variance exceeding 5 millimeters (0.19685 inches). (h) In a stairway or...

46 CFR 116.438 - Stairtowers, stairways, ladders, and elevators.

Code of Federal Regulations, 2013 CFR

2013-10-01

... landings of all stairways shall be composed of steel, and risers must be of approved incombustible material... of riser of stairs in different flights of stairs in a stairway or stairtower must be minimized. In... riser shall not have a variance exceeding 5 millimeters (0.19685 inches). (h) In a stairway or...

46 CFR 116.438 - Stairtowers, stairways, ladders, and elevators.

Code of Federal Regulations, 2014 CFR

2014-10-01

... landings of all stairways shall be composed of steel, and risers must be of approved incombustible material... of riser of stairs in different flights of stairs in a stairway or stairtower must be minimized. In... riser shall not have a variance exceeding 5 millimeters (0.19685 inches). (h) In a stairway or...

44. INTERIOR, FIRST FLOOR, NORTHEAST CORNER OF GRAND STAIRCASE (STAIRS ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

44. INTERIOR, FIRST FLOOR, NORTHEAST CORNER OF GRAND STAIRCASE (STAIRS G), SIDE AISLE, EAST WALL, THE NEGRO'S CONTRIBUTION IN THE SOCIAL AND CULTURAL DEVELOPMENT OF AMERICA: RELIGION MURAL (4' x 5' negative; 8' x 10' print) - U.S. Department of the Interior, Eighteenth & C Streets Northwest, Washington, District of Columbia, DC

78 FR 66942 - Orthopaedic and Rehabilitation Devices Panel of the Medical Devices Advisory Committee; Notice of...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-07

...., polyetheretherketone) materials. They are intended to be inserted between the vertebral bodies into the disc space from... mobility in confined spaces, at an elevated height, climb curbs, ascend/descend stairs, traverse obstacles, travel over a wider variety of terrain, and negotiate uneven/inclined surfaces. Stair-climbing...

Stair evacuation simulation based on cellular automata considering evacuees’ walk preferences

NASA Astrophysics Data System (ADS)

Ding, Ning; Zhang, Hui; Chen, Tao; Peter, B. Luh

2015-06-01

As a physical model, the cellular automata (CA) model is widely used in many areas, such as stair evacuation. However, existing CA models do not consider evacuees’ walk preferences nor psychological status, and the structure of the basic model is unapplicable for the stair structure. This paper is to improve the stair evacuation simulation by addressing these issues, and a new cellular automata model is established. Several evacuees’ walk preference and how evacuee’s psychology influences their behaviors are introduced into this model. Evacuees’ speeds will be influenced by these features. To validate this simulation, two fire drills held in two high-rise buildings are video-recorded. It is found that the simulation results are similar to the fire drill results. The structure of this model is simple, and it is easy to further develop and utilize in different buildings with various kinds of occupants. Project supported by the National Basic Research Program of China (Grant No. 2012CB719705) and the National Natural Science Foundation of China (Grant Nos. 91224008, 91024032, and 71373139).

Should we consider steps with variable height for a safer stair negotiation in older adults?

PubMed

Kunzler, Marcos R; da Rocha, Emmanuel S; Dos Santos, Christielen S; Ceccon, Fernando G; Priario, Liver A; Carpes, Felipe P

2018-01-01

Effects of exercise on foot clearances are important. In older adults variations in foot clearances during walking may lead to a fall, but there is a lack of information concerning stair negotiation in older adults. Whether a condition of post exercise changes foot clearances between steps of a staircase in older adults still unknown. To determine differences in clearances when older adults negotiate different steps of a staircase before and after a session of aerobic exercise. Kinematics data from 30 older adults were acquired and the toe and heel clearances were determined for each step. Clearances were compared between the steps. Smaller clearances were found at the highest step during ascending and descending, which was not changed by exercise. Smaller clearances suggest higher risk of tripping at the top of the staircase, regardless of exercise. A smaller step at the top of a short flight of stairs could reduce chances of tripping in older adults. It suggests that steps with variable height could make stair negotiation safer in older adults. This hypothesis should be tested in further studies.

Double closed-loop resonant micro optic gyro using hybrid digital phase modulation.

PubMed

Ma, Huilian; Zhang, Jianjie; Wang, Linglan; Jin, Zhonghe

2015-06-15

It is well-known that the closed-loop operation in optical gyros offers wider dynamic range and better linearity. By adding a stair-like digital serrodyne wave to a phase modulator can be used as a frequency shifter. The width of one stair in this stair-like digital serrodyne wave should be set equal to the optical transmission time in the resonator, which is relaxed in the hybrid digital phase modulation (HDPM) scheme. The physical mechanism for this relaxation is firstly indicated in this paper. Detailed theoretical and experimental investigations are presented for the HDPM. Simulation and experimental results show that the width of one stair is not restricted by the optical transmission time, however, it should be optimized according to the rise time of the output of the digital-to-analogue converter. Based on the optimum parameters of the HDPM, a bias stability of 0.05°/s for the integration time of 400 seconds in 1 h has been carried out in an RMOG with a waveguide ring resonator with a length of 7.9 cm and a diameter of 2.5 cm.

Enhancing the development and approval of acute stroke therapies: Stroke Therapy Academic Industry roundtable.

PubMed

Fisher, Marc; Albers, Gregory W; Donnan, Geoffrey A; Furlan, Anthony J; Grotta, James C; Kidwell, Chelsea S; Sacco, Ralph L; Wechsler, Lawrence R

2005-08-01

Previous Stroke Therapy Academic Industry Roundtable (STAIR) meetings focused on preclinical evidence of drug efficacy and enhancing acute stroke trial design and performance. A fourth (STAIR-IV) was held to discuss relevant issues related to acute stroke drug development and regulatory approval. The STAIR-IV meeting had 3 main focus areas. The first topic was novel approaches to statistical design of acute stroke trials and appropriate outcome measures. The second focus was the need for better cooperation among participants in stroke therapy development that may be addressed through a national consortium of stroke trial centers in the United States and elsewhere. Lastly, regulatory issues related to the approval of novel mono and multiple acute stroke therapies were discussed. The development of additional acute stroke therapies represents a large unmet need with many remaining challenges and also opportunities to incorporate novel approaches to clinical trial design that will lead to regulatory approval. The STAIR-IV meeting explored new concepts of trial methodology and data analysis, initiatives for implementing a US clinical trialist consortium, and pertinent regulatory issues to expedite approval of novel therapies.

Biomechanics of stair walking and jumping.

PubMed

Loy, D J; Voloshin, A S

1991-01-01

Physical activities such as stair walking and jumping result in increased dynamic loading on the human musculoskeletal system. Use of light weight, externally attached accelerometers allows for in-vivo monitoring of the shock waves invading the human musculoskeletal system during those activities. Shock waves were measured in four subjects performing stair walking up and down, jumping in place and jumping off a fixed elevation. The results obtained show that walking down a staircase induced shock waves with amplitude of 130% of that observed in walking up stairs and 250% of the shock waves experienced in level gait. The jumping test revealed levels of the shock waves nearly eight times higher than that in level walking. It was also shown that the shock waves invading the human musculoskeletal system may be generated not only by the heel strike, but also by the metatarsal strike. To moderate the risk of degenerative joint disorders four types of viscoelastic insoles were utilized to reduce the impact generated shock waves. The insoles investigated were able to reduce the amplitude of the shock wave by between 9% and 41% depending on the insole type and particular physical activity. The insoles were more effective in the reduction of the heel strike impacts than in the reduction of the metatarsal strike impacts. In all instances, the shock attenuation capacities of the insoles tested were greater in the jumping trials than in the stair walking studies. The insoles were ranked in three groups on the basis of their shock absorbing capacity.

Avoiding Stair-Step Artifacts in Image Registration for GOES-R Navigation and Registration Assessment

NASA Technical Reports Server (NTRS)

Grycewicz, Thomas J.; Tan, Bin; Isaacson, Peter J.; De Luccia, Frank J.; Dellomo, John

2016-01-01

In developing software for independent verification and validation (IVV) of the Image Navigation and Registration (INR) capability for the Geostationary Operational Environmental Satellite R Series (GOES-R) Advanced Baseline Imager (ABI), we have encountered an image registration artifact which limits the accuracy of image offset estimation at the subpixel scale using image correlation. Where the two images to be registered have the same pixel size, subpixel image registration preferentially selects registration values where the image pixel boundaries are close to lined up. Because of the shape of a curve plotting input displacement to estimated offset, we call this a stair-step artifact. When one image is at a higher resolution than the other, the stair-step artifact is minimized by correlating at the higher resolution. For validating ABI image navigation, GOES-R images are correlated with Landsat-based ground truth maps. To create the ground truth map, the Landsat image is first transformed to the perspective seen from the GOES-R satellite, and then is scaled to an appropriate pixel size. Minimizing processing time motivates choosing the map pixels to be the same size as the GOES-R pixels. At this pixel size image processing of the shift estimate is efficient, but the stair-step artifact is present. If the map pixel is very small, stair-step is not a problem, but image correlation is computation-intensive. This paper describes simulation-based selection of the scale for truth maps for registering GOES-R ABI images.

Gaze shifts during dual-tasking stair descent.

PubMed

Miyasike-daSilva, Veronica; McIlroy, William E

2016-11-01

To investigate the role of vision in stair locomotion, young adults descended a seven-step staircase during unrestricted walking (CONTROL), and while performing a concurrent visual reaction time (RT) task displayed on a monitor. The monitor was located at either 3.5 m (HIGH) or 0.5 m (LOW) above ground level at the end of the stairway, which either restricted (HIGH) or facilitated (LOW) the view of the stairs in the lower field of view as participants walked downstairs. Downward gaze shifts (recorded with an eye tracker) and gait speed were significantly reduced in HIGH and LOW compared with CONTROL. Gaze and locomotor behaviour were not different between HIGH and LOW. However, inter-individual variability increased in HIGH, in which participants combined different response characteristics including slower walking, handrail use, downward gaze, and/or increasing RTs. The fastest RTs occurred in the midsteps (non-transition steps). While gait and visual task performance were not statistically different prior to the top and bottom transition steps, gaze behaviour and RT were more variable prior to transition steps in HIGH. This study demonstrated that, in the presence of a visual task, people do not look down as often when walking downstairs and require minimum adjustments provided that the view of the stairs is available in the lower field of view. The middle of the stairs seems to require less from executive function, whereas visual attention appears a requirement to detect the last transition via gaze shifts or peripheral vision.

Effects of Descending Stair Walking on Health and Fitness of Elderly Obese Women.

PubMed

Chen, Trevor C; Hsieh, Chung-Chan; Tseng, Kuo-Wei; Ho, Chih-Chiao; Nosaka, Kazunori

2017-08-01

Eccentric exercise training produces positive fitness and health outcomes, but whether this is also the case for descending stair walking (DSW) is unknown. This study investigated the hypothesis that DSW would improve insulin sensitivity, lipid profiles and physical fitness better than ascending stair walking (ASW). Elderly (≥60 yr) obese women were placed to either DSW or ASW group (n = 15 per group). An elevator was used to eliminate ascending stairs for DSW, and descending stairs for ASW. Descending stair walking and ASW were performed twice a week for 12 wk by increasing the repetitions gradually. Overnight fasting blood samples were taken 3 d before the first training session and 4 d after the last training session, and analyzed for insulin sensitivity and lipid profile markers. Resting HR, systolic blood pressure, and diastolic blood pressure, bone mineral density, knee extensor maximal voluntary isometric contraction strength and several functional physical fitness measures were taken before and after the intervention. Average HR during DSW (88.6 ± 7.8 bpm) was lower (P < 0.05) than that of ASW (113.7 ± 10.9 bpm). Resting HR (-10%) and systolic blood pressure (-9%) decreased greater after DSW than ASW (-4% for both), and bone mineral density increased (6%) only for DSW (P < 0.05). Decreases in serum triacylglycerols, total and low-density lipoprotein cholesterols, glucose, insulin, homeostasis model assessment and whole blood glycosylated hemoglobin, and increases in high-density lipoprotein cholesterols were greater (P < 0.05) after DSW than ASW. Maximal voluntary isometric contraction strength increased greater for DSW (34%) than ASW (15%), and many of functional physical fitness measures showed greater (P < 0.05) improvement for DSW than ASW. These results supported the hypothesis and suggest that DSW is an effective exercise intervention for elderly obese women to improve their health and fitness.

Patients With Insertional Achilles Tendinopathy Exhibit Differences in Ankle Biomechanics as Opposed to Strength and Range of Motion.

PubMed

Chimenti, Ruth L; Flemister, A Samuel; Tome, Joshua; McMahon, James M; Houck, Jeff R

2016-12-01

Study Design Controlled laboratory study; cross-sectional. Background Little is known about ankle range of motion (ROM) and strength among patients with insertional Achilles tendinopathy (IAT) and whether limited ankle ROM and plantar flexor weakness impact IAT symptom severity. Objectives The purposes of the study were (1) to examine whether participants with IAT exhibit limited non-weight-bearing dorsiflexion ROM, reduced plantar flexor strength, and/or altered ankle biomechanics during stair ascent; and (2) to determine which impairments are associated with symptom severity. Methods Participants included 20 patients with unilateral IAT (mean ± SD age, 59 ± 8 years; 55% female) and 20 individuals without tendinopathy (age, 58.2 ± 8.5 years; 55% female). A dynamometer was used to measure non-weight-bearing ROM and isometric plantar flexor strength. Three-dimensional motion analysis was used to quantify ankle biomechanics during stair ascent. End-range dorsiflexion was quantified as the percentage of non-weight-bearing dorsiflexion used during stair ascent. Group differences were compared using 2-way and 1-way analyses of variance. Pearson correlations were used to test for associations among dependent variables and symptom severity. Results Groups differed in ankle biomechanics, but not non-weight-bearing ROM or strength. During stair ascent, the IAT group used greater end-range dorsiflexion (P = .03), less plantar flexion (P = .02), and lower peak ankle plantar flexor power (P = .01) than the control group. Higher end-range dorsiflexion and lower ankle power during stair ascent were associated with greater symptom severity (P<.05). Conclusion Patients with IAT do not experience restrictions in non-weight-bearing dorsiflexion ROM or isometric plantar flexor strength. However, altered ankle biomechanics during stair ascent were linked with greater symptom severity and likely contribute to decreased function. J Orthop Sports Phys Ther 2016;46(12):1051-1060. Epub 29 Oct 2016. doi:10.2519/jospt.2016.6462.

Powered ankle-foot prosthesis to assist level-ground and stair-descent gaits.

PubMed

Au, Samuel; Berniker, Max; Herr, Hugh

2008-05-01

The human ankle varies impedance and delivers net positive work during the stance period of walking. In contrast, commercially available ankle-foot prostheses are passive during stance, causing many clinical problems for transtibial amputees, including non-symmetric gait patterns, higher gait metabolism, and poorer shock absorption. In this investigation, we develop and evaluate a myoelectric-driven, finite state controller for a powered ankle-foot prosthesis that modulates both impedance and power output during stance. The system employs both sensory inputs measured local to the external prosthesis, and myoelectric inputs measured from residual limb muscles. Using local prosthetic sensing, we first develop two finite state controllers to produce biomimetic movement patterns for level-ground and stair-descent gaits. We then employ myoelectric signals as control commands to manage the transition between these finite state controllers. To transition from level-ground to stairs, the amputee flexes the gastrocnemius muscle, triggering the prosthetic ankle to plantar flex at terminal swing, and initiating the stair-descent state machine algorithm. To transition back to level-ground walking, the amputee flexes the tibialis anterior muscle, triggering the ankle to remain dorsiflexed at terminal swing, and initiating the level-ground state machine algorithm. As a preliminary evaluation of clinical efficacy, we test the device on a transtibial amputee with both the proposed controller and a conventional passive-elastic control. We find that the amputee can robustly transition between the finite state controllers through direct muscle activation, allowing rapid transitioning from level-ground to stair walking patterns. Additionally, we find that the proposed finite state controllers result in a more biomimetic ankle response, producing net propulsive work during level-ground walking and greater shock absorption during stair descent. The results of this study highlight the potential of prosthetic leg controllers that exploit neural signals to trigger terrain-appropriate, local prosthetic leg behaviors.

Self-efficacy, pain, and quadriceps capacity at baseline predict changes in mobility performance over 2 years in women with knee osteoarthritis.

PubMed

Brisson, Nicholas M; Gatti, Anthony A; Stratford, Paul W; Maly, Monica R

2018-02-01

This study examined the extent to which baseline measures of quadriceps strength, quadriceps power, knee pain and self-efficacy for functional tasks, and their interactions, predicted 2-year changes in mobility performance (walking, stair ascent, stair descent) in women with knee osteoarthritis. We hypothesized that lesser strength, power and self-efficacy, and higher pain at baseline would each be independently associated with reduced mobility over 2 years, and each of pain and self-efficacy would interact with strength and power in predicting 2-year change in stair-climbing performance. This was a longitudinal, observational study of women with clinical knee osteoarthritis. At baseline and follow-up, mobility was assessed with the Six-Minute Walk Test, and stair ascent and descent tasks. Quadriceps strength and power, knee pain, and self-efficacy for functional tasks were also collected at baseline. Multiple linear regression examined the extent to which 2-year changes in mobility performances were predicted by baseline strength, power, pain, and self-efficacy, after adjusting for covariates. Data were analyzed for 37 women with knee osteoarthritis over 2 years. Lower baseline self-efficacy predicted decreased walking (β = 1.783; p = 0.030) and stair ascent (β = -0.054; p < 0.001) performances over 2 years. Higher baseline pain intensity/frequency predicted decreased walking performance (β = 1.526; p = 0.002). Lower quadriceps strength (β = 0.051; p = 0.015) and power (β = 0.022; p = 0.022) interacted with lesser self-efficacy to predict worsening stair ascent performance. Strategies to sustain or improve mobility in women with knee osteoarthritis must focus on controlling pain and boosting self-efficacy. In those with worse self-efficacy, developing knee muscle capacity is an important target.

6. VIEW OF THE BUILDING THAT HOUSED THE STAIRS TO ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. VIEW OF THE BUILDING THAT HOUSED THE STAIRS TO THE MINE, LOOKING NORTH. THIS BUILDING STANDS APPROXIMATELY 7.62 METERS (25 FEET) FROM THE SOUTHWEST CORNER OF THE LAMP HOUSE. - Tower Hill No. 2 Mine, Approximately 0.47 mile Southwest of intersection of Stone Church Road & Township Route 561, Hibbs, Fayette County, PA

A Comparison of the DISASTER (Trademark) Scheduling Software with a Simultaneous Scheduling Algorithm for Minimizing Maximum Tardiness in Job Shops

DTIC Science & Technology

1993-09-01

goal ( Heizer , Render , and Stair, 1993:94). Integer Prgronmming. Integer programming is a general purpose approach used to optimally solve job shop...Scheduling," Operations Research Journal. 29, No 4: 646-667 (July-August 1981). Heizer , Jay, Barry Render and Ralph M. Stair, Jr. Production and Operations

Stair-rod dislocation cores acting as one-dimensional charge channels in GaAs nanowires

NASA Astrophysics Data System (ADS)

Bologna, Nicolas; Agrawal, Piyush; Campanini, Marco; Knödler, Moritz; Rossell, Marta D.; Erni, Rolf; Passerone, Daniele

2018-01-01

Aberration-corrected scanning transmission electron microscopy and density-functional theory calculations have been used to investigate the atomic and electronic structure of stair-rod dislocations connected via stacking faults in GaAs nanowires. At the apexes, two distinct dislocation cores consisting of single-column pairs of either gallium or arsenic were identified. Ab initio calculations reveal an overall reduction in the energy gap with the development of two bands of filled and empty localized states at the edges of valence and conduction bands in the Ga core and in the As core, respectively. Our results suggest the behavior of stair-rod dislocations along the nanowire as one-dimensional charge channels, which could host free carriers upon appropriate doping.

Self-Adaptive Correction of Heading Direction in Stair Climbing for Tracked Mobile Robots Using Visual Servoing Approach

NASA Astrophysics Data System (ADS)

Ji, Peng; Song, Aiguo; Song, Zimo; Liu, Yuqing; Jiang, Guohua; Zhao, Guopu

2017-02-01

In this paper, we describe a heading direction correction algorithm for a tracked mobile robot. To save hardware resources as far as possible, the mobile robot’s wrist camera is used as the only sensor, which is rotated to face stairs. An ensemble heading deviation detector is proposed to help the mobile robot correct its heading direction. To improve the generalization ability, a multi-scale Gabor filter is used to process the input image previously. Final deviation result is acquired by applying the majority vote strategy on all the classifiers’ results. The experimental results show that our detector is able to enable the mobile robot to correct its heading direction adaptively while it is climbing the stairs.

Psychometric properties of a new short version of the State-Trait Anxiety Inventory (STAI) for the assessment of anxiety in the elderly.

PubMed

Fernández-Blázquez, M A; Ávila-Villanueva, M; López-Pina, J A; Zea-Sevilla, M A; Frades-Payo, B

2015-01-01

Anxiety has negative effects on the cognitive performance and psychosocial adjustment of elderly people. Given the high prevalence of anxiety symptoms in patients suffering from cognitive impairment, it has been suggested that these symptoms may be an early marker of dementia. The State-Trait Anxiety Inventory (STAI) is one of the most widely-used scales for evaluating anxiety in elderly people. However, inasmuch as the STAI may be difficult to apply to older people, having a short form of it would be desirable. The participants comprised 489 community-dwelling individuals aged 68 years and over. All of them were volunteers in a longitudinal study for early detection of Alzheimer' Disease (Proyecto Vallecas). The full sample was divided in two homogeneous subgroups: Group A, used to reduce the number of items and response options, and Group B, the group used to determine the psychometric properties of the new short form (STAIr). A dichotomous Rasch model was used to obtain the STAIr. No statistically significant differences for STAIr scores were found with respect to sociodemographic variables. Psychometric properties and normative data were obtained for the new short version. The STAIr is composed of 13 items and data fits the model well. Since it is short and easy to apply to elderly people, STAIr will be very useful in clinical and research settings. Copyright © 2013 Sociedad Española de Neurología. Published by Elsevier España, S.L.U. All rights reserved.

13. Concrete stairs at north end of east wall of ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

13. Concrete stairs at north end of east wall of South Section, as viewed from floor of drydock. Depth measure on far left is same as in photo WA-116-E-12. Camera is pointed E. This photo makes a panorama with photo WA-116-E-3. - Puget Sound Naval Shipyard, Drydock No. 3, Farragut Avenue, Bremerton, Kitsap County, WA

Quetzal or not Quetzal, that is the question... . On the stairs of the Castillo monument in Chichen Itza

NASA Astrophysics Data System (ADS)

Elizondo-Garza, Fernando J.

2002-11-01

Some speculation will be presented about the hypothesis that states that the reflected sounds in the stairs of the Castillo building in Chichen Itza, Mexico, imitates the song of the quetzal bird. Some aspects of construction, both technical and social, are discussed as well as issues related with myth and fantasies.

19. MAIN MEETING ROOM LOOKING SOUTH FROM GALLERY. Note coved ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

19. MAIN MEETING ROOM LOOKING SOUTH FROM GALLERY. Note coved extension of gallery, erected when offices were built on gallery for the use of the Friends Service Committee in 1936. Note also the short stair balusters resulting from the wide modesty stair stringer provided for the women's side. - Twelfth Street Meeting House, 20 South Twelfth Street, Philadelphia, Philadelphia County, PA

95. VIEW OF ZINC FEEDER FROM SOUTHEAST. NOTE FEEDER CONE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

95. VIEW OF ZINC FEEDER FROM SOUTHEAST. NOTE FEEDER CONE AND PIPING FROM VACUUM RECEIVER ON LEFT. PRECIPITATE PUMP MOTOR MOUNT VISIBLE BELOW FEEDER STAIRS, PUMP AND MOTOR MISSING. SUMPS ARE LOCATED UNDER THIS FLOOR, WITH ACCESS TO HATCH TO THE RIGHT OF FEEDER STAIR. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

17. Interior of upper level (Turf Club level) of south ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

17. Interior of upper level (Turf Club level) of south and west additions to the Clubhouse. Camera pointed W. Stairs in foreground lead to the 'Gallery' room. Stairs in background lead to the 'Callahan' room. 'Broderick' room (not shown) is entered from south side of 'Gallery' room. (July 1993) - Longacres, Clubhouse & Additions, 1621 Southwest Sixteenth Street, Renton, King County, WA

Biomechanics of the ankle-foot system during stair ambulation: implications for design of advanced ankle-foot prostheses.

PubMed

Sinitski, Emily H; Hansen, Andrew H; Wilken, Jason M

2012-02-02

Unilateral lower limb prosthesis users display temporal, kinematic, and kinetic asymmetries between limbs while ascending and descending stairs. These asymmetries are due, in part, to the inability of current prosthetic devices to effectively mimic normal ankle function. The purpose of this study was to provide a comprehensive set of biomechanical data for able-bodied and unilateral transtibial amputee (TTA) ankle-foot systems for level-ground (LG), stair ascent (SA), and stair descent (SD), and to characterize deviations from normal performance associated with prosthesis use. Ankle joint kinematics, kinetics, torque-angle curves, and effective shapes were calculated for twelve able-bodied individuals and twelve individuals with TTA. The data from this study demonstrated the prosthetic limb can more effectively mimic the range of motion and power output of a normal ankle-foot during LG compared to SA and SD. There were larger differences between the prosthetic and able-bodied limbs during SA and SD, most evident in the torque-angle curves and effective shapes. These data can be used by persons designing ankle-foot prostheses and provide comparative data for assessment of future ankle-foot prosthesis designs. Published by Elsevier Ltd.

Kinematic analyses during stair descent in young women with patellofemoral pain.

PubMed

Grenholm, Anton; Stensdotter, Ann-Katrin; Häger-Ross, Charlotte

2009-01-01

Compensatory movement strategies may develop in response to pain to avoid stress on the affected area. Patellofemoral pain is characterised by intermittent periods of pain and the present study addresses whether long-term pain leads to compensatory movement strategies that remain even when the pain is absent. Lower extremity kinematics in three dimensions was studied in stair descent in 17 women with patellofemoral and in 17 matched controls. A two-dimensional geometric model was constructed to normalise kinematic data for subjects with varying anthropometrics when negotiating stairs of fixed proportions. There were minor differences in movement patterns between groups. Knee joint angular velocity in the stance leg at foot contact was lower and the movement trajectory tended to be jerkier in the patellofemoral group. The two-dimensional model showed greater plantar flexion in the swing leg in preparation for foot placement in the patellofemoral group. The results indicate that an altered stair descent strategy in the patellofemoral group may remain also in the absence of pain. The biomechanical interpretation presumes that the strategy is aimed to reduce knee joint loading by less knee joint moment and lower impact force.

Experimental Validation of Motor Primitive-Based Control for Leg Exoskeletons during Continuous Multi-Locomotion Tasks

PubMed Central

Ruiz Garate, Virginia; Parri, Andrea; Yan, Tingfang; Munih, Marko; Molino Lova, Raffaele; Vitiello, Nicola; Ronsse, Renaud

2017-01-01

An emerging approach to design locomotion assistive devices deals with reproducing desirable biological principles of human locomotion. In this paper, we present a bio-inspired controller for locomotion assistive devices based on the concept of motor primitives. The weighted combination of artificial primitives results in a set of virtual muscle stimulations. These stimulations then activate a virtual musculoskeletal model producing reference assistive torque profiles for different locomotion tasks (i.e., walking, ascending stairs, and descending stairs). The paper reports the validation of the controller through a set of experiments conducted with healthy participants. The proposed controller was tested for the first time with a unilateral leg exoskeleton assisting hip, knee, and ankle joints by delivering a fraction of the computed reference torques. Importantly, subjects performed a track involving ground-level walking, ascending stairs, and descending stairs and several transitions between these tasks. These experiments highlighted the capability of the controller to provide relevant assistive torques and to effectively handle transitions between the tasks. Subjects displayed a natural interaction with the device. Moreover, they significantly decreased the time needed to complete the track when the assistance was provided, as compared to wearing the device with no assistance. PMID:28367121

Performance Evaluation of a Lower Limb Exoskeleton for Stair Ascent and Descent with Paraplegia*

PubMed Central

Farris, Ryan J.; Quintero, Hugo A.; Goldfarb, Michael

2013-01-01

This paper describes the application of a powered lower limb exoskeleton to aid paraplegic individuals in stair ascent and descent. A brief description of the exoskeleton hardware is provided along with an explanation of the control methodology implemented to allow stair ascent and descent. Tests were performed with a paraplegic individual (T10 complete injury level) and data is presented from multiple trials, including the hip and knee joint torque and power required to perform this functionality. Joint torque and power requirements are summarized, including peak hip and knee joint torque requirements of 0.75 Nm/kg and 0.87 Nm/kg, respectively, and peak hip and knee joint power requirements of approximately 0.65 W/kg and 0.85 W/kg, respectively. PMID:23366287

iPhone Sensors in Tracking Outcome Variables of the 30-Second Chair Stand Test and Stair Climb Test to Evaluate Disability: Cross-Sectional Pilot Study

PubMed Central

Samaan, Michael A; Schultz, Brooke; Popovic, Tijana; Souza, Richard B; Majumdar, Sharmila

2017-01-01

Background Performance tests are important to characterize patient disabilities and functional changes. The Osteoarthritis Research Society International and others recommend the 30-second Chair Stand Test and Stair Climb Test, among others, as core tests that capture two distinct types of disability during activities of daily living. However, these two tests are limited by current protocols of testing in clinics. There is a need for an alternative that allows remote testing of functional capabilities during these tests in the osteoarthritis patient population. Objective Objectives are to (1) develop an app for testing the functionality of an iPhone’s accelerometer and gravity sensor and (2) conduct a pilot study objectively evaluating the criterion validity and test-retest reliability of outcome variables obtained from these sensors during the 30-second Chair Stand Test and Stair Climb Test. Methods An iOS app was developed with data collection capabilities from the built-in iPhone accelerometer and gravity sensor tools and linked to Google Firebase. A total of 24 subjects performed the 30-second Chair Stand Test with an iPhone accelerometer collecting data and an external rater manually counting sit-to-stand repetitions. A total of 21 subjects performed the Stair Climb Test with an iPhone gravity sensor turned on and an external rater timing the duration of the test on a stopwatch. App data from Firebase were converted into graphical data and exported into MATLAB for data filtering. Multiple iterations of a data processing algorithm were used to increase robustness and accuracy. MATLAB-generated outcome variables were compared to the manually determined outcome variables of each test. Pearson’s correlation coefficients (PCCs), Bland-Altman plots, intraclass correlation coefficients (ICCs), standard errors of measurement, and repeatability coefficients were generated to evaluate criterion validity, agreement, and test-retest reliability of iPhone sensor data against gold-standard manual measurements. Results App accelerometer data during the 30-second Chair Stand Test (PCC=.890) and gravity sensor data during the Stair Climb Test (PCC=.865) were highly correlated to gold-standard manual measurements. Greater than 95% of values on Bland-Altman plots comparing the manual data to the app data fell within the 95% limits of agreement. Strong intraclass correlation was found for trials of the 30-second Chair Stand Test (ICC=.968) and Stair Climb Test (ICC=.902). Standard errors of measurement for both tests were found to be within acceptable thresholds for MATLAB. Repeatability coefficients for the 30-second Chair Stand Test and Stair Climb Test were 0.629 and 1.20, respectively. Conclusions App-based performance testing of the 30-second Chair Stand Test and Stair Climb Test is valid and reliable, suggesting its applicability to future, larger-scale studies in the osteoarthritis patient population. PMID:29079549

22. Photocopy of Drawing (November 1934 Architectural Drawings by Burge ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

22. Photocopy of Drawing (November 1934 Architectural Drawings by Burge and Stevens, in Possession of the Engineering and Capital Improvements Department of the Atlanta Housing Authority, Atlanta, Georgia). SECTION AND ELEVATION, TYPE 'A' STAIR AND ENTRY, SECTION AND ELEVATION, TYPE 'C' AND 'D' STAIR AND ENTRY, TECHWOOD PROJECT #1101, SHEET A-50. - Techwood Homes, Building No. 1, 575-579 Techwood Drive, Atlanta, Fulton County, GA

37. ENGINE ROOM, FROM PORT SIDE OF CONTROL CONSOLE, LOOKING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

37. ENGINE ROOM, FROM PORT SIDE OF CONTROL CONSOLE, LOOKING TOWARDS STERN, PORT ENGINE AT RIGHT, STARBOARD ENGINE AT LEFT, BOTH ARE DIESEL ENGINES, IN BACKGROUND IS STAIRS UP TO CREWS' BERTHING, BEYONE THE STAIRS IS THE DOOR TO AFT ENGINE ROOM & MACHINE SHOP. - U.S. Coast Guard Cutter WHITE HEATH, USGS Integrated Support Command Boston, 427 Commercial Street, Boston, Suffolk County, MA

Quasi-Static Viscoelasticity Loading Measurements of an Aircraft Tire

NASA Technical Reports Server (NTRS)

Mason, Angela J.; Tanner, John A.; Johnson, Arthur R.

1997-01-01

Stair-step loading, cyclic loading, and long-term relaxation tests were performed on an aircraft tire to observe the quasi-static viscoelastic response of the tire. The data indicate that the tire continues to respond viscoelastically even after it has been softened by deformation. Load relaxation data from the stair-step test at the 15,000-lb loading was fit to a monotonically decreasing Prony series.

Knee Kinematics and Joint Moments During Stair Negotiation in Participants With Anterior Cruciate Ligament Deficiency and Reconstruction: A Systematic Review and Meta-Analysis.

PubMed

Hajizadeh, Maryam; Hashemi Oskouei, Alireza; Ghalichi, Farzan; Sole, Gisela

2016-06-01

Biomechanical changes have been reported for patients with anterior cruciate ligament deficiency (ACLD) and anterior cruciate ligament (ACL reconstruction) (ACLR), likely due to loss of stability and changes in proprioception and neuromotor control. This review evaluated kinematics and kinetics of ACLD and ACLR knees, compared with those on the contralateral uninjured sides, as well as and those in asymptomatic controls during stair navigation. This is a systematic review and meta-analysis. Electronic database searches were conducted from their original available dates to January 2015. Studies that included participants with ACLD or ACLR and reported knee joint angles or moments during stair ascent or descent were included. Nine studies met the inclusion criteria, and the methodological quality of these was assessed with a modified Downs and Black checklist. Effect sizes for differences between injured leg and uninjured contralateral leg or controls were calculated, and meta-analyses were performed if two or more studies considered the same variable. Quality assessment showed an average (± standard deviation) of 70.3% ± 7.2%. Meta-analysis showed less knee flexion at initial contact for ACLR knees compared with that in contralateral knees during stair ascent, with a moderate effect size and minimal heterogeneity. Knees with ACLD showed less peak knee flexion compared with that on contralateral sides during stair ascent, with minimal heterogeneity. External knee flexion moments were lower for ACLR compared with those in controls and contralateral sides during ascent and descent, whereas these moments were decreased for the ACLD compared with controls only during ascent. Meta-analysis results exhibited moderate/high heterogeneity or small/trivial effect sizes. Differences for kinematics and kinetics for the ACL-injured knees indicate long-term compensatory and asymmetric movement patterns while ascending and descending stairs. Due to the heterogeneity as well as the small numbers of available studies, the consequences of these differences in terms of long-term function or posttraumatic osteoarthritis need further exploration. Copyright © 2016. Published by Elsevier Inc.

Validity of FitBit, Jawbone UP, Nike+ and other wearable devices for level and stair walking.

PubMed

Huang, Yangjian; Xu, Junkai; Yu, Bo; Shull, Peter B

2016-07-01

Increased physical activity can provide numerous health benefits. The relationship between physical activity and health assumes reliable activity measurements including step count and distance traveled. This study assessed step count and distance accuracy for Nike+ FuelBand, Jawbone UP 24, Fitbit One, Fitbit Flex, Fitbit Zip, Garmin Vivofit, Yamax CW-701, and Omron HJ-321 during level, upstairs, and downstairs walking in healthy adults. Forty subjects walked on flat ground (400m), upstairs (176 steps), and downstairs (176 steps), and a subset of 10 subjects performed treadmill walking trials to assess the influence of walking speed on accuracy. Activity monitor measured step count and distance values were compared with actual step count (determined from video recordings) and distance to determine accuracy. For level walking, step count errors in Yamax CW-701, Fitbit Zip, Fitbit One, Omron HJ-321, and Jawbone UP 24 were within 1% and distance errors in Fitbit Zip and Yamax CW-701 were within 5%. Garmin Vivofit and Omron HJ-321 were the most accurate in estimating step count for stairs with errors less than 4%. An important finding is that all activity monitors overestimated distance for stair walking by at least 45%. In general, there were not accuracy differences among activity monitors for stair walking. Accuracy did not change between moderate and fast walking speeds, though slow walking increased errors for some activity monitors. Nike+ FuelBand was the least accurate step count estimator during all walking tasks. Caution should be taken when interpreting step count and distance estimates for activities involving stairs. Copyright © 2016 Elsevier B.V. All rights reserved.

Gait and muscle activation changes in men with knee osteoarthritis.

PubMed

Liikavainio, Tuomas; Bragge, Timo; Hakkarainen, Marko; Karjalainen, Pasi A; Arokoski, Jari P

2010-01-01

The aim was to examine the biomechanics of level- and stair-walking in men with knee osteoarthritis (OA) at different pre-determined gait speeds and to compare the results with those obtained from healthy control subjects. Special emphasis was placed on the estimation of joint loading. Fifty-four men with knee OA (50-69 years) and 53 healthy age- and sex-matched controls were enrolled in the study. The participants walked barefoot in the laboratory (1.2 m/s+/-5%), corridor (1.2; 1.5 and 1.7 m/s+/-5%), and climbing and coming down stairs (0.5 and 0.8 m/s+/-5%) separately. Joint loading was assessed with skin mounted accelerometers (SMAs) attached just above and below the more affected knee joint. The 3-D ground reaction forces (GRFs) and muscle activation with surface-electromyography (EMG) from vastus medialis (VM) and biceps femoris (BF) were also measured simultaneously. There were no differences in SMA variables between groups during level-walking, but maximal loading rate (LR(max)) was higher bilaterally in the controls (P<.05). Patients loaded their lower extremity more forcefully especially during stair descent at faster speed. The distinctions in muscle activation both at level- and stair ambulation in VM and BF muscles revealed that the patients used different strategies to execute the same walking tasks. It is concluded that the differences in measured SMA and GRF parameters between the knee OA patients and the controls were only minor at constant gait speeds. It is speculated that the faster speeds in the stair descent subjected the compensatory mechanisms to the maximum highlighting the differences between groups.

Ground reaction forces on stairs. Part II: knee implant patients versus normals.

PubMed

Stacoff, Alex; Kramers-de Quervain, Inès A; Luder, Gerhard; List, Renate; Stüssi, Edgar

2007-06-01

The goal of this study was to compare selected parameters of vertical ground reaction forces (GRF) of good outcome patients with different prosthesis designs with a matched control group during level walking, stair ascent and descent. Forty subjects, 29 with three main implant designs (including four subjects with a passive knee flexion restriction), and 11 healthy controls were measured with 8-10 repetitions. Vertical ground reaction forces were measured during two consecutive steps with force plates embedded in the walkway and the staircase. Defined parameters of the force signals were used to compare the results of the test groups. The results show, that, postoperatively, good outcome patients produce gait patterns of the vertical ground reaction force which are comparable to normal healthy subjects with the exception of a few distinct differences: a significant reduction (p<0.05) in the vertical loading on the operated side during level walking at take-off, at weight acceptance and take-off during stair ascent of the normal stair. During stair descent, the patients did not reduce load on the operated side, but increased load variation and side-to-side asymmetry; thus, the mechanical loads on the implants were high, which may be important information with respect to loading protocols of knee implant simulators. No systematic differences in any of the test parameters were found between posterior cruciate-retaining (LCS MB and Innex CR) versus non-retaining (LCS RP and Innex UCOR) implant designs. The restricted group showed significant reductions (p<0.05) of several loading parameters as well as an increased side-to-side asymmetry. About one third of the force parameters of the good outcome patients showed a side-to-side asymmetry between two consecutive steps, which was over a proposed level of acceptance.

Bracing of the Reconstructed and Osteoarthritic Knee during High Dynamic Load Tasks.

PubMed

Hart, Harvi F; Crossley, Kay M; Collins, Natalie J; Ackland, David C

2017-06-01

Lateral compartment osteoarthritis accompanied by abnormal knee biomechanics is frequently reported in individuals with knee osteoarthritis after anterior cruciate ligament reconstruction (ACLR). The aim of this study was to evaluate changes in knee biomechanics produced by an adjusted and unadjusted varus knee brace during high dynamic loading activities in individuals with lateral knee osteoarthritis after ACLR and valgus malalignment. Nineteen participants who had undergone ACLR 5 to 20 yr previously and had symptomatic and radiographic lateral knee osteoarthritis with valgus malalignment were assessed. Quantitative motion analysis experiments were conducted during hopping, stair ascent, and descent under three test conditions: (i) no brace, (ii) unadjusted brace with sagittal plane support and neutral frontal plane alignment, and (iii) adjusted brace with sagittal plane support and varus realignment (valgus to neutral). Sagittal, frontal, and transverse plane knee kinematics, external joint moment, and angular impulse data were calculated. Relative to an unbraced knee, braced conditions significantly increased knee flexion and adduction angles during hopping (P = 0.003 and P = 0.005; respectively), stair ascent (P = 0.003 and P < 0.001, respectively), and descent (P = 0.009 and P < 0.001, respectively). In addition, the brace conditions increased knee flexion (P < 0.001) and adduction (P = 0.001) angular impulses and knee stiffness (P < 0.001) during hopping, as well as increased knee adduction moments during stair ascent (P = 0.008) and flexion moments during stair descent (P = 0.006). There were no significant differences between the adjusted and the unadjusted brace conditions (P > 0.05). A knee brace, with or without varus alignment, can modulate knee kinematics and external joint moments during hopping, stairs ascent, and descent in individuals with predominant lateral knee osteoarthritis after ACLR. Longer-term use of a brace may have implications in slowing osteoarthritis progression.

Eye Movement Patterns of the Elderly during Stair Descent:Effect of Illumination

NASA Astrophysics Data System (ADS)

Kasahara, Satoko; Okabe, Sonoko; Nakazato, Naoko; Ohno, Yuko

The relationship between the eye movement pattern during stair descent and illumination was studied in 4 elderly people in comparison with that in 5 young people. The illumination condition was light (85.0±30.9 lx) or dark (0.7±0.3 lx), and data of eye movements were obtained using an eye mark recorder. A flight of 15 steps was used for the experiment, and data on 3 steps in the middle, on which the descent movements were stabilized, were analyzed. The elderly subjects pointed their eyes mostly directly in front in the facial direction regardless of the illumination condition, but the young subjects tended to look down under the light condition. The young subjects are considered to have confirmed the safety of the front by peripheral vision, checked the stepping surface by central vision, and still maintained the upright position without leaning forward during stair descent. The elderly subjects, in contrast, always looked at the visual target by central vision even under the light condition and leaned forward. The range of eye movements was larger vertically than horizontally in both groups, and a characteristic eye movement pattern of repeating a vertical shuttle movement synchronous with descent of each step was observed. Under the dark condition, the young subjects widened the range of vertical eye movements and reduced duration of fixation. The elderly subjects showed no change in the range of eye movements but increased duration of fixation during stair descent. These differences in the eye movements are considered to be compensatory reactions to narrowing of the vertical visual field, reduced dark adaptation, and reduced dynamic visual acuity due to aging. These characteristics of eye movements of the elderly lead to an anteriorly leaned posture and lack of attention to the front during stair descent.

Improved Training Method for Rapid Rehabilitation of Amputees

DTIC Science & Technology

2012-03-01

amputees must be able to manage uneven terrain, crowded environments, stairs , ramps, and hills. The largest problem for a lower extremity amputee is...objective biomechanical variables that are causally related to the success or failure in avoiding a fall after a trip, objective tests to quantify...crowded environments, stairs , ramps, and hills. The key factor that limits the ability of amputees to achieve maximum functional capabilities is falls

iPhone Sensors in Tracking Outcome Variables of the 30-Second Chair Stand Test and Stair Climb Test to Evaluate Disability: Cross-Sectional Pilot Study.

PubMed

Adusumilli, Gautam; Joseph, Solomon Eben; Samaan, Michael A; Schultz, Brooke; Popovic, Tijana; Souza, Richard B; Majumdar, Sharmila

2017-10-27

Performance tests are important to characterize patient disabilities and functional changes. The Osteoarthritis Research Society International and others recommend the 30-second Chair Stand Test and Stair Climb Test, among others, as core tests that capture two distinct types of disability during activities of daily living. However, these two tests are limited by current protocols of testing in clinics. There is a need for an alternative that allows remote testing of functional capabilities during these tests in the osteoarthritis patient population. Objectives are to (1) develop an app for testing the functionality of an iPhone's accelerometer and gravity sensor and (2) conduct a pilot study objectively evaluating the criterion validity and test-retest reliability of outcome variables obtained from these sensors during the 30-second Chair Stand Test and Stair Climb Test. An iOS app was developed with data collection capabilities from the built-in iPhone accelerometer and gravity sensor tools and linked to Google Firebase. A total of 24 subjects performed the 30-second Chair Stand Test with an iPhone accelerometer collecting data and an external rater manually counting sit-to-stand repetitions. A total of 21 subjects performed the Stair Climb Test with an iPhone gravity sensor turned on and an external rater timing the duration of the test on a stopwatch. App data from Firebase were converted into graphical data and exported into MATLAB for data filtering. Multiple iterations of a data processing algorithm were used to increase robustness and accuracy. MATLAB-generated outcome variables were compared to the manually determined outcome variables of each test. Pearson's correlation coefficients (PCCs), Bland-Altman plots, intraclass correlation coefficients (ICCs), standard errors of measurement, and repeatability coefficients were generated to evaluate criterion validity, agreement, and test-retest reliability of iPhone sensor data against gold-standard manual measurements. App accelerometer data during the 30-second Chair Stand Test (PCC=.890) and gravity sensor data during the Stair Climb Test (PCC=.865) were highly correlated to gold-standard manual measurements. Greater than 95% of values on Bland-Altman plots comparing the manual data to the app data fell within the 95% limits of agreement. Strong intraclass correlation was found for trials of the 30-second Chair Stand Test (ICC=.968) and Stair Climb Test (ICC=.902). Standard errors of measurement for both tests were found to be within acceptable thresholds for MATLAB. Repeatability coefficients for the 30-second Chair Stand Test and Stair Climb Test were 0.629 and 1.20, respectively. App-based performance testing of the 30-second Chair Stand Test and Stair Climb Test is valid and reliable, suggesting its applicability to future, larger-scale studies in the osteoarthritis patient population. ©Gautam Adusumilli, Solomon Eben Joseph, Michael A Samaan, Brooke Schultz, Tijana Popovic, Richard B Souza, Sharmila Majumdar. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 27.10.2017.

14. LION SCULPTURE, AT THE PHILADELPHIA MUSEUM OF ART, MOVED ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

14. LION SCULPTURE, AT THE PHILADELPHIA MUSEUM OF ART, MOVED FROM MERCHANTS' EXCHANGE, WHERE IT RESTED ON THE STAIR WALL OF SIDE ENTRANCE STAIRS. (A REPLACEMENT LION HAS BEEN PLACED IN THE ORIGINAL SITE, AS DID ANOTHER REPLACEMENT IN THE OTHER SIDE OF THE BUILDING. FOR THIS LATTER REPLACEMENT SEE PA-1028-15). A VIEW OF THE MUSEUM IS IN THE BACKGROUND - Philadelphia Exchange Company, 143 South Third Street, Philadelphia, Philadelphia County, PA

Influence of Total Knee Arthroplasty on Gait Mechanics of the Replaced and Non-Replaced Limb During Stair Negotiation.

PubMed

Standifird, Tyler W; Saxton, Arnold M; Coe, Dawn P; Cates, Harold E; Reinbolt, Jeffrey A; Zhang, Songning

2016-01-01

This study compared biomechanics during stair ascent in replaced and non-replaced limbs of total knee arthroplasty (TKA) patients with control limbs of healthy participants. Thirteen TKA patients and fifteen controls performed stair ascent. Replaced and non-replaced knees of TKA patients were less flexed at contact compared to controls. The loading response peak knee extension moment was greater in control and non-replaced knees compared with replaced. The push-off peak knee abduction moment was elevated in replaced limbs compared to controls. Loading and push-off peak hip abduction moments were greater in replaced limbs compared to controls. The push-off peak hip abduction moment was greater in non-replaced limbs compared to controls. Future rehabilitation protocols should consider the replaced knee and also the non-replaced knee and surrounding joints. Copyright © 2016 Elsevier Inc. All rights reserved.

Alterations in knee kinematics after partial medial meniscectomy are activity dependent.

PubMed

Edd, Shannon N; Netravali, Nathan A; Favre, Julien; Giori, Nicholas J; Andriacchi, Thomas P

2015-06-01

Alterations in knee kinematics after partial meniscectomy have been linked to the increased risk of osteoarthritis in this population. Understanding differences in kinematics during static versus dynamic activities of increased demand can provide important information regarding the possible underlying mechanisms of these alterations. Differences in the following 2 kinematics measures will increase with activity demand: (1) the offset toward external tibial rotation for the meniscectomized limb compared with the contralateral limb during stance and (2) the difference in knee flexion angle at initial foot contact between the meniscectomized and contralateral limbs. Controlled laboratory study. This study compared side-to-side differences in knee flexion and rotation angles during static and dynamic activities. Thirteen patients (2 female) were tested in a motion capture laboratory at 6 ± 2 months after unilateral, arthroscopic, partial medial meniscectomy during a static reference pose and during 3 dynamic activities: walking, stair ascent, and stair descent. The meniscectomized limb demonstrated more external tibial rotation compared with the contralateral limb during dynamic activities, and there was a trend that this offset increased with activity demand (repeated-measures analysis of variance [ANOVA] for activity, P = .07; mean limb difference: static pose, -0.1° ± 3.3°, P = .5; walking, 1.2° ± 3.8°, P = .1; stair ascent, 2.0° ± 3.2°, P = .02; stair descent, 3.0° ± 3.5°, P = .005). Similarly, the meniscectomized knee was more flexed at initial contact than the contralateral limb during dynamic activities (repeated-measures ANOVA for activity P = .006; mean limb difference: reference pose, 1.0° ± 2.5°, P = .09; walking, 2.0° ± 3.9°, P = .05; stair ascent, 5.9° ± 5.3°, P = .009; stair descent, 3.5° ± 4.0°, P = .004). These results suggest both a structural element and a potential muscular element for the differences in kinematics after partial medial meniscectomy and highlight the importance of challenging the knee with activities of increased demands to detect differences in kinematics from the contralateral limb. With further investigation, these findings could help guide clinical rehabilitation of patients with torn meniscus tissue, especially in the context of the patients' increased risk of joint degeneration. © 2015 The Author(s).

Which is the best predictor of excessive hip internal rotation in women with patellofemoral pain: Rearfoot eversion or hip muscle strength? Exploring subgroups.

PubMed

Ferreira, Amanda Schenatto; de Oliveira Silva, Danilo; Briani, Ronaldo Valdir; Ferrari, Deisi; Aragão, Fernando Amâncio; Pazzinatto, Marcella Ferraz; de Azevedo, Fábio Mícolis

2018-03-26

Patellofemoral pain (PFP) has been linked to increased patellofemoral joint stress as a result of excessive hip internal rotation. Lower hip strength and/or excessive rearfoot eversion have been used to explain such altered movement pattern; however, it is unknown which one is the best predictor of excessive hip internal rotation. To investigate if peak rearfoot eversion and/or peak concentric hip abductor strength can predict peak hip internal rotation during stair ascent in women with PFP. This cross-sectional study included thirty-seven women with PFP which underwent three-dimensional kinematic analysis during stair ascent and hip abductor strength analysis in an isokinetic dynamometer. A forced entry linear regression model analysis was carried out to determine which independent variables present the best capability to predict the hip internal rotation. Peak concentric hip abductor strength significantly predicted peak hip internal rotation during stair ascent (R 2  = 0.27, p = 0.001). Peak rearfoot eversion did not predict peak hip internal rotation during stair ascent (R 2  < 0.01, p = 0.62). A Post-hoc analysis was conducted to explore if a subgroup with excessive rearfoot eversion would predict hip internal rotation. Based on a previous reported cut-off point, 48.6% of the participants were classified as excessive rearfoot eversion. For the subgroup with excessive rearfoot eversion, peak concentric hip abductor strength and peak rearfoot eversion significantly predicted peak hip internal rotation during stair ascent (R 2  = 0.26, p = 0.02; R 2  = 0.42, p = 0.003, respectively). For non-excessive rearfoot eversion subgroup, peak concentric hip abductor strength significantly predicted peak hip internal rotation during stair ascent (R 2  = 0.53; p < 0.001); and peak rearfoot eversion did not (R 2  = 0.01; p = 0.65). Findings indicate that hip muscle strength seems to be related with hip internal rotation in all women with PFP. Rearfoot eversion seems to be related with hip internal rotation only in a subgroup with excessive rearfoot eversion. Copyright © 2018. Published by Elsevier B.V.

Astronaut Brian Duffy, mission commander for the STS-72 mission, prepares to ascend stairs to the

NASA Technical Reports Server (NTRS)

1996-01-01

STS-72 TRAINING VIEW --- Astronaut Brian Duffy, mission commander for the STS-72 mission, prepares to ascend stairs to the flight deck of the fixed base Shuttle Mission Simulator (SMS) at the Johnson Space Center (JSC). Duffy will be joined by four other NASA astronauts and an international mission specialist aboard the Space Shuttle Endeavour for a scheduled nine-day mission, now set for the winter of this year.

Section AA through main entrance gates & west stairs. San ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Section AA through main entrance gates & west stairs. San Bernardino Valley Union Junior College, Science Building. Also includes plans and sections of boys' and girls' toilets. Howard E. Jones, Architect, San Bernardino, California. Sheet 5, job no. 311. Scales 1/4 inch to the foot (section AA) and 1/2 inch to the foot (toilet rooms). February 15, 1927. - San Bernardino Valley College, Life Science Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

Characteristics of a Maritime Interdiction Operations Unmanned Ground Vehicle

DTIC Science & Technology

2012-04-01

obstacles taller than its height. It comes with a suite of software that provides behaviors such as automatic self-righting and stair climbing (although the...unit we tested was a prototype and the stair climbing behavior had not been perfected). It also has a small wrist-mounted OCU with a touch screen...operations, often in hostile environments. There is a need for a small tactical robot that can be deployed ahead of the team to provide enhanced

Repeated 3-minute stair climbing-descending exercise after a meal over 2 weeks increases serum 1,5-anhydroglucitol levels in people with type 2 diabetes

PubMed Central

Honda, Hiroto; Igaki, Makoto; Hatanaka, Yuki; Komatsu, Motoaki; Tanaka, Shin-Ichiro; Miki, Tetsuo; Matsuki, Yumika; Takaishi, Tetsuo; Hayashi, Tatsuya

2017-01-01

[Purpose] The purpose of this study was to examine the hypoglycemic effect of a postprandial exercise program using brief stair climbing-descending exercise in people with type 2 diabetes. [Subjects and Methods] Seven males with uncomplicated type 2 diabetes (age 68.0 ± 3.7 years) performed two sets of stair climbing-descending exercise 60 and 120 min after each meal for the first 2 weeks but not for the following 2 weeks. Each set of exercise comprised 3-min of continuous repetition of climbing briskly to the second floor followed by slow waking down to the first floor in their home. A rest period of 1–2 min was allowed between each set. [Results] Serum 1,5-anhydroglucitol level was significantly higher by 11.5% at the end of the 2-week exercise period than at the baseline. By contrast, the 1,5-anhydroglucitol level at the end of the following 2-week period did not differ from the baseline value. Fasting blood glucose level and insulin resistance index at the end of the exercise period did not differ from the baseline value. [Conclusion] Repeated 3-min bouts of stair climbing-descending exercise after a meal may be a promising method for improving postprandial glycemic control in people with type 2 diabetes. PMID:28210043

Evaluation of left-right difference of impulse in impact forces at stance phase: comparison of measurements on flat land and stairs

PubMed Central

Tasato, Hiroshi; Kida, Noriyuki

2018-01-01

[Purpose] The purpose of this study was to investigate the measurement method and parameters to simply evaluate the condition of the knee that are necessary for preventing locomotive syndrome as advocated by the Japan Orthopedic Association. [Subjects and Methods] The subjects installed acceleration sensors in lateral condyles of the tibia and measured acceleration and load under the conditions of walking on a flat ground and walking using stairs; the difference between the impulse of impact forces (acceleration × load) of the two knees was defined as a simple evaluation parameter. [Results] Simple evaluation parameters were not correlated with age during walking on a flat ground, but during walking using stairs, it was almost flat up to the age of 20–40 years, and after the age of 49 years, based on the quadratic curve approximation (R2=0.99), a correlation of simple evaluation parameters with age could be confirmed. [Conclusion] The simple evaluation parameter during walking using stairs was highly correlated with age, suggesting a contribution to preventing locomotive syndrome by improving reliability. In the future, we plan to improve reliability by increasing the data, and establish it as a simple evaluation parameter that can be used for preventing locomotive syndrome in elderly people and those with KL classification grades 0–1. PMID:29706699

[How to make your own custom cutting guides for both mandibular and fibular stair step osteotomies?

PubMed

Rem, K; Bosc, R; De Kermadec, H; Hersant, B; Meningaud, J-P

2017-12-01

Using tailored cutting guides for osteocutaneous free fibula flap in complex mandibular reconstruction after cancer resection surgery constitutes a substantial improvement. Autonomously conceiving and manufacturing the cutting guides within a plastic surgery department with computer-aided design (CAD) and three-dimensional (3D) printing allows planning more complex osteotomies, such as stair-step osteotomies, in order to achieve more stable internal fixations. For the past three years, we have been producing by ourselves patient-tailored cutting guides using CAD and 3D printing. Osteotomies were virtually planned, making the cutting lines more complex in order to optimize the internal fixation stability. We also printed reconstructed mandible templates and shaped the reconstruction plates on them. We recorded data including manufacturing techniques and surgical outcomes. Eleven consecutive patients were operated on for an oral cavity cancer. For each patient, we planned the fibular and mandibular stair-step osteotomies and we produced tailored cutting guides. In all patients, we achieved to get immediately stable internal fixations and in 10 patients, a complete bone consolidation after 6 months. Autonomously manufacturing surgical cutting guides for mandibular reconstruction by free fibula flap is a significant improvement, regarding ergonomics and precision. Planning stair-step osteotomies to perform complementary internal fixation increases contact surface and congruence between the bone segments, thus improving the reconstructed mandible stability. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Depression as a moderator of STAIR Narrative Therapy for women with post-traumatic stress disorder related to childhood abuse.

PubMed

Cloitre, Marylene; Garvert, Donn W; Weiss, Brandon J

2017-01-01

Background : Depression among those who have experienced childhood abuse is associated with earlier onset, more persistent and severe symptoms, more frequent relapse, and poorer treatment outcomes across a variety of psychiatric disorders. In addition, individuals with a history of childhood abuse are more likely to develop post-traumatic stress disorder (PTSD) co-occurring with depression. Objective : This study evaluated whether severity of depression moderated the outcome in a PTSD treatment for childhood abuse survivors. Specifically, we assessed whether individuals with significant depression obtained better outcomes when provided with a two-module treatment which included a skills training component with behavioral activation interventions, Skills Training in Affective and Interpersonal Regulation (STAIR) followed by a trauma-focused component, Narrative Therapy, as compared to two control conditions where one component (STAIR or Narrative Therapy) was replaced with Supportive Counseling. Method : Participants were 104 women with PTSD related to childhood abuse. Participants were randomized into three conditions: (1) STAIR plus Narrative Therapy (SNT), (2) STAIR plus Supportive Counseling (SSC), and (3) Supportive Counseling plus Narrative Therapy (SCNT). Clinician-Administered PTSD Scale for DSM-IV (CAPS-IV) PTSD symptom severity was assessed at pre-treatment, post-treatment, and 3 and 6 month follow-up. Results : Participants with severe depression showed superior PTSD symptom reduction following SNT, while those in the other two conditions experienced a loss of improvement after treatment ended. A similar finding was obtained among those with moderate depression, while among those with low levels of depression, outcomes did not differ across the three treatment conditions. Conclusions : Childhood abuse survivors with severe depression obtained superior outcomes in a treatment that combined skills training with trauma-focused work. Skills packages which contain behavioral activation interventions in combination with trauma-focused work may be particularly beneficial for patients with childhood abuse and severe depression.

Combined versus individual effects of a valgus knee brace and lateral wedge foot orthotic during stair use in patients with knee osteoarthritis.

PubMed

Moyer, Rebecca; Birmingham, Trevor; Dombroski, Colin; Walsh, Robert; Giffin, J Robert

2017-05-01

The aim of this study was to investigate the combined and individual biomechanical effects of a valgus knee brace and a lateral wedge foot orthotic during stair ascent and descent in patients with knee osteoarthritis (OA). Thirty-five patients with varus alignment and medial knee OA were prescribed a custom valgus knee brace and lateral wedge foot orthotic. Knee angles and moments in the frontal and sagittal planes were determined from 3D gait analysis completed under four randomized conditions: (1) control (no knee brace or foot orthotic), (2) knee brace, (3) foot orthotic, and (4) combined knee brace and foot orthotic. Additional measures included the vertical ground reaction force, trunk lean, toe out and gait speed. During the combined use of a knee brace and foot orthotic, significant decreases in the knee adduction angle (2.17, 95%CI: 0.50-3.84, p=0.013) and 2nd peak EKAM (0.35, 95%CI: 0.17-0.52, p<0.001) were observed during stair descent; and significant increases in the EKFM were observed during stair ascent (0.54, 95%CI: 0.30-0.78, p<0.001) and descent (1stpk: 0.48, 95%CI: 0.15-0.80, p=0.005; 2ndpk: 0.55, 95%CI: 0.34-0.76, p<0.001). Fewer gait compensations were observed between conditions during stair descent compared to ascent, except for toe out. Findings suggest greater effects on gait when both knee brace and foot orthotic are used together, resulting in a more normal gait pattern. However, whether or not a true change in knee joint load can be inferred when using these orthoses remains unclear. Further research is required to determine the clinical importance of the observed changes. Copyright © 2017. Published by Elsevier B.V.

Joint loading decreased by inexpensive and minimalist footwear in elderly women with knee osteoarthritis during stair descent.

PubMed

Sacco, I C N; Trombini-Souza, F; Butugan, M K; Pássaro, A C; Arnone, A C; Fuller, R

2012-03-01

Previous studies indicate that flexible footwear, which mimics the biomechanics of walking barefoot, results in decreased knee loads in patients with knee osteoarthritis (OA) during walking. However, the effect of flexible footwear on other activities of daily living, such as descending stairs, remains unclear. Our objective was to evaluate the influence of inexpensive and minimalist footwear (Moleca) on knee adduction moment (KAM) during stair descent of elderly women with and without knee OA. Thirty-four elderly women were equally divided into an OA group and a control group (CG). Stair descent was evaluated in barefoot condition, while wearing the Moleca, and while wearing heeled shoes. Kinematics and ground reaction forces were measured to calculate KAM by using inverse dynamics. The OA group experienced a higher KAM during midstance under the barefoot condition (233.3%; P = 0.028), the Moleca (379.2%; P = 0.004), and heeled shoes (217.6%; P = 0.007). The OA group had a similar knee load during early, mid, and late stance with the Moleca compared with the barefoot condition. Heeled shoes increased the knee loads during the early-stance (versus barefoot [16.7%; P < 0.001] and versus the Moleca [15.5%; P < 0.001]), midstance (versus barefoot [8.6%; P = 0.014] and versus the Moleca [9.5%; P = 0.010]), and late-stance phase (versus barefoot [10.6%; P = 0.003] and versus the Moleca [9.2%; P < 0.001]). In the CG, the Moleca produced a knee load similar to the barefoot condition only during the early-stance phase. Besides the general foot protection, the inexpensive and minimalist footwear contributes to decreasing knee loads in elderly women with OA during stair descent. The loads are similar to the barefoot condition and effectively decreased when compared with heeled shoes. Copyright © 2012 by the American College of Rheumatology.

Development of a Mobile Robot with Wavy Movement by Rotating Bars

NASA Astrophysics Data System (ADS)

Kitagawa, Ato; Zhang, Liang; Eguchi, Takashi; Tsukagoshi, Hideyuki

A mobile robot with a new type of movement called wavy movement is proposed in this paper. Wavy movement can be readily realized by many bars or crosses which are rotating at equivalent speeds, and the robot with simple structure and easy control method is able to ascend and descend stairs by covering the corners of stairs within separate wave shapes between touching points. The principle of wavy movement, the mechanism, and the experimental result of the proposed robot are discussed.

Development and Testing of a Hybrid Wheg (trademark)-Mobile Platform for Autonomous Surf-Zone Operations

DTIC Science & Technology

2011-12-01

7 Figure 2.1 Force body diagram of a wheel. . . . . . . . . . . . . . . . . . . . . . 9 Figure 2.2 Force body diagram of a person climbing stairs ...person climbing stairs . . . . . 10 Figure 2.4 Plot of the height of center above ground vs. rotation angle for a wheel and Wheg...tail was able to climb an obstacle six centimeters higher than a similar robot with six Whegs [6].The addition of a tail shifted the center of mass

nanoSTAIR: a new strategic proposal to impulse standardization in nanotechnology research

NASA Astrophysics Data System (ADS)

López de Ipiña, J. M.; Salvi, O.; Hazebrouck, B.; Jovanovic, A.; Carre, F.; Saamanen, A.; Brouwer, D.; Schmitt, M.; Martin, S.

2015-05-01

Nanotechnology is considered one of the key technologies of the 21st century within Europe and a Key-Enabling Technology (KET) by Horizon 2020. Standardization has been identified in H2020 as one of the innovation-support measures by bridging the gap between research and the market, and helping the fast and easy transfer of research results to the European and international market. The development of new and improved standards requires high quality technical information, creating a fundamental interdependency between the standardization and research communities. In the frame of project nanoSTAIR (GA 319092), the present paper describes the European scenario on research and standardization in nanotechnology and presents a proposal of a European strategy (nanoSTAIR) to impulse direct “pipelines” between research and standardization. In addition, strategic actions focused on integration of standardization in the R&D projects, from the early stages of the design of a future business (Project Proposal), are also described.

Determining Criteria to Predict Repeatability of Performance in Older Adults: Using Coefficients of Variation for Strength and Functional Measures.

PubMed

Raj, Isaac Selva; Bird, Stephen R; Westfold, Ben A; Shield, Anthony J

2017-01-01

Reliable measures of muscle strength and functional capacity in older adults are essential. The aim of this study was to determine whether coefficients of variation (CVs) of individuals obtained at the first session can infer repeatability of performance in a subsequent session. Forty-eight healthy older adults (mean age 68.6 ± 6.1 years; age range 60-80 years) completed two assessment sessions, and on each occasion undertook: dynamometry for isometric and isokinetic quadriceps strength, 6 meter fast walk (6MFWT), timed up and go (TUG), stair climb and descent, and vertical jump. Significant linear relationships were observed between CVs in session 1 and the percentage difference between sessions 1 and 2 for torque at 60, 120, 240 and 360°/s, 6MFWT, TUG, stair climb, and stair descent. The results of this study could be used to establish criteria for determining an acceptably reliable performance in strength and functional tests.

Design of instructions for evacuating disabled adults.

PubMed

Boyce, Michael W; Al-Awar Smither, Janan; Fisher, Daniel O; Hancock, P A

2017-01-01

We investigated how the design of instructions can affect performance in preparing emergency stair travel devices for the evacuation of disable individuals. We had three hypotheses: 1) Design of instructions would account for a significant portion of explained performance variance, 2) Improvements in design of instructions would reduce time on task across device type and age group, and 3) There would be a performance decrement for older adults compared to younger adults based on the slowing of older adult information processing abilities. Results showed that design of instructions does indeed account for a large portion of explained variance in the operation of emergency stair travel devices, and that improvements in design of instructions can reduce time on task across device type and age group. However, encouragingly for real-world operations, results did not indicate any significant differences between older versus younger adults. We look to explore ways that individuals with disabilities can exploit these insights to enhance the performance of emergency stair travel devices for use. Copyright © 2016 Elsevier Ltd. All rights reserved.

Reduced knee flexion is a possible cause of increased loading rates in individuals with patellofemoral pain.

PubMed

Silva, Danilo de Oliveira; Briani, Ronaldo Valdir; Pazzinatto, Marcella Ferraz; Ferrari, Deisi; Aragão, Fernando Amâncio; Azevedo, Fábio Mícolis de

2015-11-01

Stair ascent is an activity that exacerbates symptoms of individuals with patellofemoral pain. The discomfort associated with this activity usually results in gait modification such as reduced knee flexion in an attempt to reduce pain. Although such compensatory strategy is a logical approach to decrease pain, it also reduces the normal active shock absorption increasing loading rates and may lead to deleterious and degenerative changes of the knee joint. Thus, the aims of this study were (i) to investigate whether there is reduced knee flexion in adults with PFP compared to healthy controls; and (ii) to analyze loading rates in these subjects, during stair climbing. Twenty-nine individuals with patellofemoral pain and twenty-five control individuals (18-30 years) participated in this study. Each subject underwent three-dimensional kinematic and kinetic analyses during stair climbing on two separate days. Between-groups analyses of variance were performed to identify differences in peak knee flexion and loading rates. Intraclass correlation coefficient was performed to verify the reliability of the variables. On both days, the patellofemoral pain group demonstrated significantly reduced peak knee flexion and increased loading rates. In addition, the two variables obtained high to very high reliability. Reduced knee flexion during stair climbing as a strategy to avoid anterior knee pain does not seem to be healthy for lower limb mechanical distributions. Repeated loading at higher loading rates may be damaging to lower limb joints. Copyright © 2015 Elsevier Ltd. All rights reserved.

Clinical and biomechanical assessment of patella resurfacing in total knee arthroplasty.

PubMed

Berti, Lisa; Benedetti, Maria Grazia; Ensini, Andrea; Catani, Fabio; Giannini, Sandro

2006-07-01

Currently there is a limited understanding of the factors influencing range of motion by comparing patellar resurfacing vs non-resurfacing in total knee arthroplasty during activities of daily living. A recent meta-analysis of patellar replacement confirms better outcome with patella resurfacing; however, the result can be influenced by many other factors, such as: component design, surgeon experience, and technical aspects of the surgery. This study compares the biomechanics of the knee in patients after total knee arthroplasty with and without patellar resurfacing during stair climbing. Forty-seven patients with total knee arthroplasty were assessed at the mean follow-up of 24 months. In all of them a posterior stabilised fixed bearing prosthesis (Optetrak PS, Exactech) was implanted. Twenty-six patients were treated without patellar resurfacing and 21 with patellar resurfacing. Clinical evaluations were performed using the International Knee Society and the Hospital for Special Surgery scores. Ten patients with patellar resurfacing and 10 patients without patellar resurfacing were also studied with motion analysis during stair climbing; 10 healthy subjects were studied for statistical comparison. Clinical passive knee flexion, International Knee Society Function and Hospital for Special Surgery scores were significantly higher in the patellar resurfacing group. During stair climbing, active knee joint range of motion during the stance phase was greater in patients with patellar resurfacing. The maximum adduction moment was significantly higher in the group without patellar resurfacing. Patients with patellar resurfacing demonstrated better clinical scores, and kinematic and kinetic data while ascending stairs.

In Vivo Patellar Tracking and Patellofemoral Cartilage Contacts during Dynamic Stair Ascending

PubMed Central

Suzuki, Takashi; Hosseini, Ali; Li, Jing-Sheng; Gill, Thomas J; Li, Guoan

2012-01-01

The knowledge of normal patellar tracking is essential for understanding of the knee joint function and for diagnosis of patellar instabilities. This paper investigated the patellar tracking and patellofemoral joint contact locations during a stair ascending activity using a validated dual-fluoroscopic imaging system. The results showed that the patellar flexion angle decreased from 41.9° to 7.5° with the knee extension during stair ascending. During first 80% of the activity, the patella shifted medially about 3.9 mm and then slightly shifted laterally during the last 20% of the ascending activity. Anterior translation of 13 mm of the patella was measured at the early 80% of the activity and then slightly moved posteriorly by about 2 mm at the last 20% of the activity. The path of the cartilage contact points was slightly lateral on the cartilage surfaces of patella and femur. On the patellar cartilage surface, the cartilage contact locations were about 2 mm laterally from heel strike to 60% of the stair ascending activity and moved laterally and reached 5.3 mm at full extension. However, the cartilage contact locations were relatively constant on the femoral cartilage surface (~5 mm lateral). The patellar tracking pattern was consistent with the patellofemoral cartilage contact location pattern. These data could provide baseline knowledge for understanding of normal physiology of the patellofemoral joint and can be used as a reference for clinical evaluation of patellofemoral disorder symptoms. PMID:22840488

The effectiveness of front fork systems at damping accelerations during isolated aspects specific to cross-country mountain biking.

PubMed

Macdermid, Paul W; Miller, Matthew C; Fink, Philip W; Stannard, Stephen R

2017-11-01

Cross-country mountain bike suspension reportedly enhances comfort and performance through reduced vibration and impact exposure. This study analysed the effectiveness of three different front fork systems at damping accelerations during the crossing of three isolated obstacles (stairs, drop, and root). One participant completed three trials on six separate occasions in a randomised order using rigid, air-sprung, and carbon leaf-sprung forks. Performance was determined by time to cross obstacles, while triaxial accelerometers quantified impact exposure and damping response. Results identified significant main effect of fork type for performance time (p < 0.05). The air-sprung and leaf-sprung forks were significantly slower than the rigid forks for the stairs (p < 0.05), while air-sprung suspension was slower than the rigid for the root protocol (p < 0.05). There were no differences for the drop protocol (p < 0.05). Rigid forks reduced overall exposure (p < 0.05), specifically at the handlebars for the stairs and drop trials. More detailed analysis presented smaller vertical accelerations at the handlebar for air-sprung and leaf-sprung forks on the stairs (p < 0.05), and drop (p < 0.05) but not the root. As such, it appears that the suspension systems tested were ineffective at reducing overall impact exposure at the handlebar during isolated aspects of cross-country terrain features which may be influenced to a larger extent by rider technique.

Probable Earthquake Archaeological Effects in the ancient pyramids of Quetzalcóatl and Sun in Teotihuacán (Central Mexico)

NASA Astrophysics Data System (ADS)

Perez-Lopez, Raul; Rodríguez-Pascua, Miguel Angel; Garduño-Monroy, Victor Hugo; Oliveros, Arturo; Giner-Robles, Jorge L.; Silva, Pablo G.

2010-05-01

Teotihuacán was one of the blooming and greater cities of the Prehispanic cultural period within the central valley of México and one of the best archaeological findings of the Earth. During the period of splendour (Middle-Late Classic Period, 350-650 AD), almost 125.000 inhabitants lived in a vast city with more than 2000 stucco and block buildings, including the great religious and ceremonial pyramids: the Great Sun Pyramid, built between 1- 150 AD, the Moon Pyramid, built during a large time span (1-650 AD) and the outstanding Quetzalcóatl Pyramid (Feathered Snake Temple), built in two phases: the first original edifice built before 350 AD and the second one mainly are repairs of the west side and dated post-350 AD. The Quetzalcóatl Pyramid (Q- pyramid) shows a quadrangular base of ca. 3500 m2 with an extraordinary decoration of feathered snakes (attributed to the God Quetzalcóatl) and lizards. The second phase of construction consisted in a townhouse façade covering the west side of the pyramid (post 350AD), up to now with no evidence to justify such annexed wrapper of this west side. This ceremonial building was built within the Citadel, a complex area of Teotihuacán with residential and common zones as well (i.e. market). A detailed view of the steps of the west side stairs, displays different patterns of deformation affecting the blocks of the stair. The original and ancient stair exhibits rotated, overturned and displaced blocks, being stronger this deformation at the base of the pyramid. Moreover, the upper corners of the blocks appear broken in a similar form than the seismic-related feature defined as dipping broken corners or chipped corners. However, the horizontal disposition of the blocks suggests lateral vibration between them from horizontal shaking propagation. Besides, this feature appears lesser evident affecting the lower blocks of the annexed west façade, the only originally preserved ones. We have carried out a systematic measurement of this feature across the original west stairs of the Q- pyramid and the first stair level of the Sun pyramid. Furthermore, these horizontal dipping broken corners were also described affecting the new stairs of the annexed façade of the Q- pyramid. This suggests that seismic shaking could produce that deformation with a relative date of 350 AD post-quem. More data are necessary to properly test the earthquake occurrence and to bracket a probable intensity value.

Lidar-based door and stair detection from a mobile robot

NASA Astrophysics Data System (ADS)

Bansal, Mayank; Southall, Ben; Matei, Bogdan; Eledath, Jayan; Sawhney, Harpreet

2010-04-01

We present an on-the-move LIDAR-based object detection system for autonomous and semi-autonomous unmanned vehicle systems. In this paper we make several contributions: (i) we describe an algorithm for real-time detection of objects such as doors and stairs in indoor environments; (ii) we describe efficient data structures and algorithms for processing 3D point clouds acquired by laser scanners in a streaming manner, which minimize the memory copying and access. We show qualitative results demonstrating the effectiveness of our approach on runs in an indoor office environment.

Foldable Walker

NASA Technical Reports Server (NTRS)

1979-01-01

Paraplegics, who number about 100,000 in the United States, depend on crutches for their mobility on level ground. But crutches are ineffective on stairways; for climbing or descending, the paraplegic needs a stable pair of rails to push against. Aluminum metal walkers are designed for use on level surfaces, hence they have little utility on stairs; and, although lightweight, they are too heavy to be carried by the paraplegic while walking on crutches. There exists a need for a walker specifically designed for stair use and made of material much lighter than aluminum.

Foot-mounted inertial measurement unit for activity classification.

PubMed

Ghobadi, Mostafa; Esfahani, Ehsan T

2014-01-01

This paper proposes a classification technique for daily base activity recognition for human monitoring during physical therapy in home. The proposed method estimates the foot motion using single inertial measurement unit, then segments the motion into steps classify them by template-matching as walking, stairs up or stairs down steps. The results show a high accuracy of activity recognition. Unlike previous works which are limited to activity recognition, the proposed approach is more qualitative by providing similarity index of any activity to its desired template which can be used to assess subjects improvement.

14. Stairs in far NW corner of the North Section, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

14. Stairs in far NW corner of the North Section, as viewed from atop pier. This photo, along with phot WA-116-E-1, are the only photographs of the North Section of Drydock 3 that were approved by the U.S. Navy for inclusion in this HAER report. The brick building in center distance is the Building 59, the Pattern Shop, which has been documented in the HAER report No. WA-116-A. - Puget Sound Naval Shipyard, Drydock No. 3, Farragut Avenue, Bremerton, Kitsap County, WA

Movement Patterns of the Knee During Gait Following ACL Reconstruction: A Systematic Review and Meta-Analysis.

PubMed

Kaur, Mandeep; Ribeiro, Daniel Cury; Theis, Jean-Claude; Webster, Kate E; Sole, Gisela

2016-12-01

Altered gait patterns follow ing anterior cruciate ligament reconstruction (ACLR) may be associated with long-term impairments and post-traumatic osteoarthritis. This systematic review and meta-analysis compared lower limb kinematics and kinetics of the ACL reconstructed knee with (1) the contralateral limb and (2) healthy age-matched participants during walking, stair climbing, and running. The secondary aim was to describe the differences over time following ACLR for these biomechanical variables. Database searches were conducted from inception to July 2014 and updated in August 2015 for studies exploring peak knee angles and moments following ACLR during walking, stair negotiation, and running. Risk of bias was assessed with a modified Downs and Black quality index for all included studies, and meta-analyses were performed. Forest plots were explored qualitatively for recovery of gait variables over time after surgery. A total of 40 studies were included in the review; 26 of these were rated as low risk and 14 as high risk of bias. The meta-analysis included 27 studies. Strong to moderate evidence indicated no significant difference in peak flexion angles between ACLR and control groups during walking and stair ascent. Strong evidence was found for lower peak flexion moments in participants with ACLR compared with control groups and contralateral limb during walking and stair activities. Strong to moderate evidence was found for lower peak adduction moment in ACLR participants for the injured compared with the contralateral limbs during walking and stair descent. The qualitative assessment for recovery over time indicated a pattern towards restoration of peak knee flexion angle with increasing time from post-surgery. Peak knee adduction moments were lower within the first year following surgery and higher than controls during later phases (5 years). Joint kinematics are restored, on average, 6 years following reconstruction, while knee external flexion moments remain lower than controls. Knee adduction moments are lower during early phases following reconstruction, but are higher than controls, on average, 5 years post-surgery. Findings indicate that knee function is not fully restored following reconstruction, and long-term maintenance programs may be needed.

Occupational Physical Activity Habits of UK Office Workers: Cross-Sectional Data from the Active Buildings Study.

PubMed

Smith, Lee; Sawyer, Alexia; Gardner, Benjamin; Seppala, Katri; Ucci, Marcella; Marmot, Alexi; Lally, Pippa; Fisher, Abi

2018-06-09

Habitual behaviours are learned responses that are triggered automatically by associated environmental cues. The unvarying nature of most workplace settings makes workplace physical activity a prime candidate for a habitual behaviour, yet the role of habit strength in occupational physical activity has not been investigated. Aims of the present study were to: (i) document occupational physical activity habit strength; and (ii) investigate associations between occupational activity habit strength and occupational physical activity levels. A sample of UK office-based workers ( n = 116; 53% female, median age 40 years, SD 10.52) was fitted with activPAL accelerometers worn for 24 h on five consecutive days, providing an objective measure of occupational step counts, stepping time, sitting time, standing time and sit-to-stand transitions. A self-report index measured the automaticity of two occupational physical activities (“being active” (e.g., walking to printers and coffee machines) and “stair climbing”). Adjusted linear regression models investigated the association between occupational activity habit strength and objectively-measured occupational step counts, stepping time, sitting time, standing time and sit-to-stand transitions. Eighty-one per cent of the sample reported habits for “being active”, and 62% reported habits for “stair climbing”. In adjusted models, reported habit strength for “being active” were positively associated with average occupational sit-to-stand transitions per hour (B = 0.340, 95% CI: 0.053 to 0.627, p = 0.021). “Stair climbing” habit strength was unexpectedly negatively associated with average hourly stepping time (B = −0.01, 95% CI: −0.01 to −0.00, p = 0.006) and average hourly occupational step count (B = −38.34, 95% CI: −72.81 to −3.88, p = 0.030), which may reflect that people with stronger stair-climbing habits compensate by walking fewer steps overall. Results suggest that stair-climbing and office-based occupational activity can be habitual. Interventions might fruitfully promote habitual workplace activity, although, in light of potential compensation effects, such interventions should perhaps focus on promoting moderate-intensity activity.

Taking the stairs instead: The impact of workplace design standards on health promotion strategies.

PubMed

McGann, Sarah; Jancey, Jonine; Tye, Marian

2013-01-01

Comprehensive health promotion in Western Australia has been conducted from the point of views of policy development, promotion, education and service delivery. Much of this recent work has been focused on supporting workplaces - but there has yet to be any real focus on the design of the actual physical workplace environment from a health promotion perspective. This paper is aimed at highlighting the gap in health promotion knowledge by addressing how the disciplines of architecture and health promotion can work together to challenge the regulations that dictate design practice and ultimately bridge that gap for long-term change. The overarching aim is to undertake further evidenced-based research that will inform best practice in the planning and design of workplaces to reduce sedentary behaviour and increase opportunities for physical activity. Within this wide objective this paper focuses in particular on the idea of stairs-versus-lift movement strategies within office buildings. By examining building design guidelines from a health promotion perspective we expose a central dichotomy, where health promotion posters say "Take the stairs instead" whereas the language of building design suggests that the lift is best. From a design point of view, the National Codes of Construction (NCC), formally known as the Building Codes of Australia (BCA), the essential technical regulation for all building design and construction, primarily addresses the concepts of 'egress' and 'travel distance' for escape in the event of fire, and building access in terms of universal access. Additionally, The Property Council of Australia's Guide to Office Building Quality prioritises lift performance criteria along with the quality and experience of lift use as a major grading factor. There is no provision in either set of standards for staircase quality and experience. The stairs, despite being promoted as better life choice for better health, is not promoted through these building codes nor, consequently, through the building design in actuality. It is proposed that health promotion strategies could be coupled with design-led movement strategies in workplace design so that the promotional language, such as "take the stairs instead", is balanced by the design language of the building.

Kinematic differences exist between transtibial amputee fallers and non-fallers during downwards step transitioning.

PubMed

Vanicek, Natalie; Strike, Siobhán C; Polman, Remco

2015-08-01

Stair negotiation is biomechanically more challenging than level gait. There are few biomechanical assessments of transtibial amputees descending stairs and none specifically related to falls. Stair descent may elicit more differences than level gait in amputees with and without a previous falls history. The aim of this study was to compare the gait kinematics of fallers and non-fallers during downwards step transitioning in transtibial amputees. Cross-sectional study. Six fallers and five non-fallers completed step transition trials on a three-step staircase at their self-selected pace. Nine participants exhibited a clear preference to lead with the affected limb, while two had no preference. Four participants self-selected a step-to rather than a reciprocal stair descent strategy. The fallers who used a reciprocal strategy walked 44% more quickly than the non-fallers. To compensate for the lack of active plantar flexion of the prosthetic foot, exaggerated range of motion occurred proximally at the pelvis during swing. The step-to group was more reliant on the handrails than the reciprocal group and walked more slowly. As anticipated, the fallers walked faster than the non-fallers despite employing the more difficult 'roll-over' technique. Handrail use could help to improve dynamic control during downwards step transitions. Transtibial amputees are advised to descend steps using external support, such as handrails, for enhanced dynamic control. Hip abductor and knee extensor eccentric strength should be improved through targeted exercise. Prosthetic socket fit should be checked to allow adequate knee range of motion on the affected side. © The International Society for Prosthetics and Orthotics 2014.

Proximal mechanics during stair ascent are more discriminate of females with patellofemoral pain than distal mechanics.

PubMed

de Oliveira Silva, Danilo; Barton, Christian John; Pazzinatto, Marcella Ferraz; Briani, Ronaldo Valdir; de Azevedo, Fábio Mícolis

2016-06-01

Several hypotheses have been proposed to explain the pathomechanisms underlying patellofemoral pain (PFP). Concurrent evaluation of lower limb mechanics in the same PFP population is needed to determine which may be more important to target during rehabilitation. This study aimed to investigate possible differences in rearfoot eversion, hip adduction, and knee flexion during stair ascent; the relationship between these variables; and the discriminatory capability of each in identifying females with PFP. Thirty-six females with PFP and 31 asymptomatic controls underwent three-dimensional kinematic analyses during stair ascent. Between-group comparisons were made for peak rearfoot eversion, hip adduction, and knee flexion. Pearson's correlation coefficients were calculated to evaluate relationships among these parameters. Receiver operating characteristic curves were applied to identify the discriminatory capability of each. Females with PFP ascended stairs with reduced peak knee flexion, greater peak hip adduction and peak rearfoot eversion. Peak hip adduction (>10.6°; sensitivity=67%, specificity=77%) discriminated females with PFP more effectively than rearfoot eversion (>5.0°; sensitivity=58%, specificity=67%). Reduced peak hip adduction was found to be associated with reduced peak knee flexion (r=0.54, p=0.002) in females with PFP. These findings indicate that proximal, local, and distal kinematics should be considered in PFP management, but proximally targeted interventions may be most important. The relationship of reduced knee flexion with reduced hip adduction also indicates a possible compensatory strategy to reduce patellofemoral joint stress, and this may need to be addressed during rehabilitation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of stair-climbing on balance, gait, strength, resting heart rate, and submaximal endurance in healthy seniors.

PubMed

Donath, L; Faude, O; Roth, R; Zahner, L

2014-04-01

Stair-climbing serves as a feasible opportunity to remain physically active within everyday-life. Data on neuromuscular and cardiorespiratory performance after regular stair-climbing in seniors are scarce. Forty-eight seniors were stratified to a one- (taking every step, INT1) or two-step strategy (every second step, INT2) or a control group (CON). Thirty-nine seniors [females: n = 22, males: n = 17; age: 70.5 (SD 5.1) years; BMI: 25.8 (3.1) kg/m(2)] completed the 8-week intervention (three weekly sessions). Before and after the intervention, balance, gait, strength, and submaximal endurance (at different intensities) were assessed. Maximal strength and explosive power did not improve significantly (0.10 < P < 0.78). Resting heart rate was significantly reduced in INT2 (-8/min) compared with INT1 (0/min, P = 0.02) and CON (0/min, P = 0.03). Compared with CON, perceived exertion for all intensities (0.007 < P < 0.03) and submaximal exercise heart rate during moderate uphill walking significantly decreased (-11/min; P < 0.05) in INT2. Step counts for forward beam balancing (4.5 cm width) increased in INT2 (P = 0.007) compared with CON. With more pronounced effects in INT2, stair-climbing significantly improved resting and exercise heart rates, perceived exertion, and dynamic balance performance in healthy seniors and may contribute to better overall fitness, reduced fall risk, and less perceived strain during daily life activities. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Mechanical energy transfers across lower limb segments during stair ascent and descent in young and healthy older adults.

PubMed

Novak, Alison C; Li, Qingguo; Yang, Shuozhi; Brouwer, Brenda

2011-07-01

Older adults present with altered movement patterns during stair negotiation although the extent to which modifications in pattern and speed influence mechanical efficiency is unknown. This study evaluated mechanical energy transfers attributed to active force production during stair negotiation in young and older adults to provide insight into age-related changes in mechanical efficiency. Secondary analysis on data obtained from 23 young (23.7±3.0 years) and 32 older adults (67.0±8.2 years) during self-paced stair ascent and descent was conducted. Mechanical energy expenditures (MEE) during concentric transfer, eccentric transfer and no-transfer phases were determined for the ankle, knee and hip power profiles in the sagittal plane. Mechanical energy compensations (MEC) were also determined at each joint. During ascent, MEEs were similar for young and older adults although older adults compensated ankle muscles to a lesser extent during concentric muscle action. Controlling for cadence eliminated this difference. During descent, older adults demonstrated lower energy expenditures at the ankle and hip and similar expenditures at the knee compared to young adults. Changes in joint MEE in the older group resulted in reduced energy compensation at the ankle during concentric and eccentric activity and at the knee during eccentric activity. These age-related differences in mechanical energy transfers and related adjustments in MEC were not a function of the slower cadence in older adults and suggest a loss in mechanical efficiency. These results provide a benchmark against which physical impairments in older adults may be explored. Copyright © 2011 Elsevier B.V. All rights reserved.

The VSPA Foot: A Quasi-Passive Ankle-Foot Prosthesis With Continuously Variable Stiffness.

PubMed

Shepherd, Max K; Rouse, Elliott J

2017-12-01

Most commercially available prosthetic feet do not exhibit a biomimetic torque-angle relationship, and are unable to modulate their mechanics to assist with other mobility tasks, such as stairs and ramps. In this paper, we present a quasi-passive ankle-foot prosthesis with a customizable torque-angle curve and an ability to quickly modulate ankle stiffness between tasks. The customizable torque-angle curve is obtained with a cam-based transmission and a fiberglass leaf spring. To achieve variable stiffness, the leaf spring's support conditions can be actively modulated by a small motor, shifting the torque-angle curve to be more or less stiff. We introduce the design, characterize the available torque-angle curves, and present kinematics from a transtibial amputee subject performing level-ground walking, stair ascent/descent, and ramp ascent/descent. The subject exhibited a more normative range of motion on stairs and ramps at lower stiffness levels, and preferred different stiffness levels for each task. Paired with an appropriate intent recognition system, our novel ankle prosthesis could improve gait biomechanics during walking and many other mobility tasks.

Computational Modelling and Movement Analysis of Hip Joint with Muscles

NASA Astrophysics Data System (ADS)

Siswanto, W. A.; Yoon, C. C.; Salleh, S. Md.; Ngali, M. Z.; Yusup, Eliza M.

2017-01-01

In this study, the model of hip joint and the main muscles are modelled by finite elements. The parts included in the model are hip joint, hemi pelvis, gluteus maximus, quadratus femoris and gamellus inferior. The materials that used in these model are isotropic elastic, Mooney Rivlin and Neo-hookean. The hip resultant force of the normal gait and stair climbing are applied on the model of hip joint. The responses of displacement, stress and strain of the muscles are then recorded. FEBio non-linear solver for biomechanics is employed to conduct the simulation of the model of hip joint with muscles. The contact interfaces that used in this model are sliding contact and tied contact. From the analysis results, the gluteus maximus has the maximum displacement, stress and strain in the stair climbing. Quadratus femoris and gamellus inferior has the maximum displacement and strain in the normal gait however the maximum stress in the stair climbing. Besides that, the computational model of hip joint with muscles is produced for research and investigation platform. The model can be used as a visualization platform of hip joint.

A study on a wheel-based stair-climbing robot with a hopping mechanism

NASA Astrophysics Data System (ADS)

Kikuchi, Koki; Sakaguchi, Keisuke; Sudo, Takayuki; Bushida, Naoki; Chiba, Yasuhiro; Asai, Yuji

2008-08-01

In this study, we propose a simple hopping mechanism using the vibration of a two-degree-of-freedom system for a wheel-based stair-climbing robot. The robot, consisting of two bodies connected by springs and a wire, hops by releasing energy stored in the springs and quickly travels using wheels mounted in its lower body. The trajectories of the bodies during hopping change in accordance with the design parameters, such as the reduced mass of the two bodies, the mass ratio between the upper and lower bodies, the spring constant, the control parameters such as the initial contraction of the spring and the wire tension. This property allows the robot to quickly and economically climb up and down stairs, leap over obstacles, and landing softly without complex control. In this paper, the characteristics of hopping motion for the design and control parameters are clarified by both numerical simulations and experiments. Furthermore, using the robot design based on the results the abilities to hop up and down a step, leap over a cable, and land softly are demonstrated.

Patellofemoral pain syndrome: electromyography in a frequency domain analysis

NASA Astrophysics Data System (ADS)

Catelli, D. S.; Kuriki, H. U.; Polito, L. F.; Azevedo, F. M.; Negrão Filho, R. F.; Alves, N.

2011-09-01

The Patellofemoral Pain Syndrome (PFPS), has a multifactorial etiology and affects approximately 7 to 15% of the population, mostly women, youth, adults and active persons. PFPS causes anterior or retropatelar pain that is exacerbated during functional motor gestures, such as up and down stairs or spending long periods of time sitting, squatting or kneeling. As the diagnostic evaluation of this syndrome is still indirect, different mechanisms and methodologies try to make a classification that distinguishes patients with PFPS in relation to asymptomatic. Thereby, the purpose of this investigation was to determine the characteristics of the electromyographic (EMG) signal in the frequency domain of the vastus medialis oblique (VMO) and vastus lateralis (VL) in patients with PFPS, during the ascent of stairs. 33 young women (22 control group and 11 PFPS group), were evaluated by EMG during ascent of stairs. The VMO mean power frequency (MPF) and the VL frequency 95% (F95) were lower in symptomatic individuals. This may be related to the difference in muscle recruitment strategy exerted by each muscle in the PFPS group compared to the control group.

Inertial measurements of free-living activities: assessing mobility to predict falls.

PubMed

Wang, Kejia; Lovell, Nigel H; Del Rosario, Michael B; Liu, Ying; Wang, Jingjing; Narayanan, Michael R; Brodie, Matthew A D; Delbaere, Kim; Menant, Jasmine; Lord, Stephen R; Redmond, Stephen J

2014-01-01

An exploratory analysis was conducted into how simple features, from acceleration at the lower back and ankle during simulated free-living walking, stair ascent and descent, correlate with age, the overall fall risk from a clinically validated Physiological Profile Assessment (PPA), and its sub-components. Inertial data were captured from 92 older adults aged 78-95 (42 female, mean age 84.1, standard deviation 3.9 years). The dominant frequency, peak width from Welch's power spectral density estimate, and signal variance along each axis, from each sensor location and for each activity were calculated. Several correlations were found between these features and the physiological risk factors. The strongest correlations were from the dominant frequency at the ankle along the mediolateral direction during stair ascent (Spearman's correlation coefficient p = - 0.45) with anterioposterior sway, and signal variance of the anterioposterior acceleration at the lower back during stair descent (p = - 0.45) with age. These findings should aid future attempts to classify activities and predict falls in older adults, based on true free-living data from a range of activities.

Cardiovascular Health Effects of Internet-Based Encouragements to Do Daily Workplace Stair-Walks: Randomized Controlled Trial

PubMed Central

Sundstrup, Emil; Boysen, Marianne; Jakobsen, Markus Due; Mortensen, Ole Steen; Persson, Roger

2013-01-01

Background Although the hazardous health effects of a sedentary lifestyle are well known, many adults struggle with regular physical activity. Simple and efficient encouragements for increased physical activity are needed. Objective To determine the effect on cardiovascular health of email-based encouragements to do daily stair-walks at work together with colleagues among adults in sedentary occupations. Methods A single-blind randomized controlled trial was performed at a large administrative company in Copenhagen, Denmark. Participants were 160 office workers (125 women, 35 men; mean age 42 years, SD 10; sitting 89.5% of work time). At baseline, aerobic fitness was 37 mL/min/kg (SD 9), mean blood pressure was 118/79 mmHg (SD 14/9), and mean body mass index (BMI) was 23 kg/m2 (SD 4). Participants were randomly assigned (2:1 ratio) to an email group receiving weekly email-based encouragements to walk the stairs for 10 minutes a day or to a control group receiving weekly reminders to continue their usual physical activities. The primary outcome was the change from baseline to 10-week follow-up in aerobic fitness determined from a maximal cycle test. The examiner was blinded to group allocation. Results Adherence to the email encouragements was fairly high with 82.7% of the participants performing at least 3 sessions of 10-minute stair-walks per week (mean 3.3, SD 1.3). Mean heart rate reached 167 beats/min (SD 10) during stair-walks. In the intention-to-treat analysis, aerobic fitness increased 1.45 mL/min/kg (95% CI 0.64-2.27) at 10-week follow-up in the email group compared with the control group. In participants with low aerobic fitness at baseline (n=56), aerobic fitness increased 1.89 mL/min/kg (95% CI 0.53-3.24), and systolic and diastolic blood pressure decreased 4.81 mmHg (95% CI 0.47-9.16) and 2.67 mmHg (95% CI 0.01-5.32), respectively, in the email group compared with the control group. Body weight decreased in the email group of those with low aerobic fitness compared with the control group, but this was not statistically significant. Conclusions Simple and inexpensive email-based encouragements to do daily stair-walks together with colleagues at work improves cardiovascular health among adults in sedentary occupations. There exists an enormous potential to prevent the hazardous health effects of a sedentary lifestyle through the use of email-based encouragements to do short bouts of physical activity at the workplace. Trial Registration Clinicaltrials.gov NCT01293253; http://clinicaltrials.gov/ct2/show/NCT01293253 (Archived by WebCite at http://www.webcitation.org/6HWG2jw68). PMID:23793032

Cardiovascular health effects of internet-based encouragements to do daily workplace stair-walks: randomized controlled trial.

PubMed

Andersen, Lars Louis; Sundstrup, Emil; Boysen, Marianne; Jakobsen, Markus Due; Mortensen, Ole Steen; Persson, Roger

2013-06-21

Although the hazardous health effects of a sedentary lifestyle are well known, many adults struggle with regular physical activity. Simple and efficient encouragements for increased physical activity are needed. To determine the effect on cardiovascular health of email-based encouragements to do daily stair-walks at work together with colleagues among adults in sedentary occupations. A single-blind randomized controlled trial was performed at a large administrative company in Copenhagen, Denmark. Participants were 160 office workers (125 women, 35 men; mean age 42 years, SD 10; sitting 89.5% of work time). At baseline, aerobic fitness was 37 mL/min/kg (SD 9), mean blood pressure was 118/79 mmHg (SD 14/9), and mean body mass index (BMI) was 23 kg/m(2) (SD 4). Participants were randomly assigned (2:1 ratio) to an email group receiving weekly email-based encouragements to walk the stairs for 10 minutes a day or to a control group receiving weekly reminders to continue their usual physical activities. The primary outcome was the change from baseline to 10-week follow-up in aerobic fitness determined from a maximal cycle test. The examiner was blinded to group allocation. Adherence to the email encouragements was fairly high with 82.7% of the participants performing at least 3 sessions of 10-minute stair-walks per week (mean 3.3, SD 1.3). Mean heart rate reached 167 beats/min (SD 10) during stair-walks. In the intention-to-treat analysis, aerobic fitness increased 1.45 mL/min/kg (95% CI 0.64-2.27) at 10-week follow-up in the email group compared with the control group. In participants with low aerobic fitness at baseline (n=56), aerobic fitness increased 1.89 mL/min/kg (95% CI 0.53-3.24), and systolic and diastolic blood pressure decreased 4.81 mmHg (95% CI 0.47-9.16) and 2.67 mmHg (95% CI 0.01-5.32), respectively, in the email group compared with the control group. Body weight decreased in the email group of those with low aerobic fitness compared with the control group, but this was not statistically significant. Simple and inexpensive email-based encouragements to do daily stair-walks together with colleagues at work improves cardiovascular health among adults in sedentary occupations. There exists an enormous potential to prevent the hazardous health effects of a sedentary lifestyle through the use of email-based encouragements to do short bouts of physical activity at the workplace. Clinicaltrials.gov NCT01293253; http://clinicaltrials.gov/ct2/show/NCT01293253 (Archived by WebCite at http://www.webcitation.org/6HWG2jw68).

Study on stair-step liquid triggered capillary valve for microfluidic systems

NASA Astrophysics Data System (ADS)

Zhang, Lei; Jones, Ben; Majeed, Bivragh; Nishiyama, Yukari; Okumura, Yasuaki; Stakenborg, Tim

2018-06-01

In lab-on-a-chip systems, various microfluidic technologies are being developed to handle fluids at very small quantities, e.g. in the scale of nano- or pico-liter. To achieve autonomous fluid handling at a low cost, passive fluidic control, based on the capillary force between the liquid and microchannel surface, is of the utmost interest in the microsystem. Valves are an essential component for flow control in many microfluidic systems, which enables a sequence of fluidic operations to be performed. In this paper, we present a new passive valve structure for a capillary driven microfluidic device. It is a variation of a capillary trigger valve that is amenable to silicon microfabrication; it will be referred to as a stair-step liquid triggered valve. In this paper, the valve functionality and its dependencies on channel geometry, surface contact angle, and surface roughness are studied both experimentally and with numerical modeling. The effect of the contact angle was explored in experiments on the silicon microfabricated valve structure; a maximal working contact angle, above which the valve fails to be triggered, was demonstrated. The fluidic behavior in the stair-step channel structure was further explored computationally using the finite volume method with the volume-of-fluid approach. Surface roughness due to scalloping of the sidewall during the Bosch etch process was hypothesized to reduce the sidewall contact angle. The reduced contact angle has considerable impacts on the capillary pressure as the liquid vapor interface traverses the stair-step structure of the valve. An improved match in the maximal working contact angle between the experiments and model was obtained when considering this surface roughness effect.

Towards Real-Time Detection of Gait Events on Different Terrains Using Time-Frequency Analysis and Peak Heuristics Algorithm.

PubMed

Zhou, Hui; Ji, Ning; Samuel, Oluwarotimi Williams; Cao, Yafei; Zhao, Zheyi; Chen, Shixiong; Li, Guanglin

2016-10-01

Real-time detection of gait events can be applied as a reliable input to control drop foot correction devices and lower-limb prostheses. Among the different sensors used to acquire the signals associated with walking for gait event detection, the accelerometer is considered as a preferable sensor due to its convenience of use, small size, low cost, reliability, and low power consumption. Based on the acceleration signals, different algorithms have been proposed to detect toe off (TO) and heel strike (HS) gait events in previous studies. While these algorithms could achieve a relatively reasonable performance in gait event detection, they suffer from limitations such as poor real-time performance and are less reliable in the cases of up stair and down stair terrains. In this study, a new algorithm is proposed to detect the gait events on three walking terrains in real-time based on the analysis of acceleration jerk signals with a time-frequency method to obtain gait parameters, and then the determination of the peaks of jerk signals using peak heuristics. The performance of the newly proposed algorithm was evaluated with eight healthy subjects when they were walking on level ground, up stairs, and down stairs. Our experimental results showed that the mean F1 scores of the proposed algorithm were above 0.98 for HS event detection and 0.95 for TO event detection on the three terrains. This indicates that the current algorithm would be robust and accurate for gait event detection on different terrains. Findings from the current study suggest that the proposed method may be a preferable option in some applications such as drop foot correction devices and leg prostheses.

Towards Real-Time Detection of Gait Events on Different Terrains Using Time-Frequency Analysis and Peak Heuristics Algorithm

PubMed Central

Zhou, Hui; Ji, Ning; Samuel, Oluwarotimi Williams; Cao, Yafei; Zhao, Zheyi; Chen, Shixiong; Li, Guanglin

2016-01-01

Real-time detection of gait events can be applied as a reliable input to control drop foot correction devices and lower-limb prostheses. Among the different sensors used to acquire the signals associated with walking for gait event detection, the accelerometer is considered as a preferable sensor due to its convenience of use, small size, low cost, reliability, and low power consumption. Based on the acceleration signals, different algorithms have been proposed to detect toe off (TO) and heel strike (HS) gait events in previous studies. While these algorithms could achieve a relatively reasonable performance in gait event detection, they suffer from limitations such as poor real-time performance and are less reliable in the cases of up stair and down stair terrains. In this study, a new algorithm is proposed to detect the gait events on three walking terrains in real-time based on the analysis of acceleration jerk signals with a time-frequency method to obtain gait parameters, and then the determination of the peaks of jerk signals using peak heuristics. The performance of the newly proposed algorithm was evaluated with eight healthy subjects when they were walking on level ground, up stairs, and down stairs. Our experimental results showed that the mean F1 scores of the proposed algorithm were above 0.98 for HS event detection and 0.95 for TO event detection on the three terrains. This indicates that the current algorithm would be robust and accurate for gait event detection on different terrains. Findings from the current study suggest that the proposed method may be a preferable option in some applications such as drop foot correction devices and leg prostheses. PMID:27706086

Does it pay to have a damper in a powered ankle prosthesis? A power-energy perspective.

PubMed

Eslamy, Mahdy; Grimmer, Martin; Rinderknecht, Stephan; Seyfarth, Andre

2013-06-01

In this paper we investigated on peak power (PP) and energy (ER) requirements for different active ankle actuation concepts that can have both elasticity and damping characteristics. A lower PP or ER requirement is an important issue because it will lead to a smaller motor or battery. In addition to spring, these actuation concepts are assumed to have (passive) damper in series (series elastic-damper actuator SEDA) or parallel (parallel elastic-damper actuator PEDA) to the motor. For SEA (series elastic actuator), SEDA and PEDA, we calculated the required minimum motor PP and ER in different human gaits: normal level walking, ascending and descending the stairs. We found that for level walking and ascending the stairs, the SEA concept, and for descending, the SEDA, were the favorable concepts to reduce required minimum PP and ER in comparison to a DD (direct drive) concept. In SEDA concept, the minimum PP could be reduced to half of what SEA would require. Nevertheless, it was found that spring was always required, however damper showed 'task specific' advantages. As a result, if a simple design perspective is in mind, from PP-ER viewpoint, SEA could be the best compromise to be used for different above-mentioned gaits. For SEDA or PEDA concepts, a controllable damper should be used. In addition, our results show that it is beneficial to select spring stiffness in SEA, based on level walking gait. The PP and ER requirements would increase very slightly for stairs ascending, and to some extent (10.5%) for descending as a consequence of this selection. In contrast, stiffness selection based on stair ascending or descending, increases the PP requirements of level walking more noticeably (17-24%).

Contributory factors to unsteadiness during walking up and down stairs in patients with diabetic peripheral neuropathy.

PubMed

Handsaker, Joseph C; Brown, Steven J; Bowling, Frank L; Cooper, Glen; Maganaris, Constantinos N; Boulton, Andrew J M; Reeves, Neil D

2014-11-01

Although patients with diabetic peripheral neuropathy (DPN) are more likely to fall than age-matched controls, the underlying causative factors are not yet fully understood. This study examines the effects of diabetes and neuropathy on strength generation and muscle activation patterns during walking up and down stairs, with implications for fall risk. Sixty-three participants (21 patients with DPN, 21 diabetic controls, and 21 healthy controls) were examined while walking up and down a custom-built staircase. The speed of strength generation at the ankle and knee and muscle activation patterns of the ankle and knee extensor muscles were analyzed. Patients with neuropathy displayed significantly slower ankle and knee strength generation than healthy controls during stair ascent and descent (P < 0.05). During ascent, the ankle and knee extensor muscles were activated significantly later by patients with neuropathy and took longer to reach peak activation (P < 0.05). During descent, neuropathic patients activated the ankle extensors significantly earlier, and the ankle and knee extensors took significantly longer to reach peak activation (P < 0.05). Patients with DPN are slower at generating strength at the ankle and knee than control participants during walking up and down stairs. These changes, which are likely caused by altered activations of the extensor muscles, increase the likelihood of instability and may be important contributory factors for the increased risk of falling. Resistance exercise training may be a potential clinical intervention for improving these aspects and thereby potentially reducing fall risk. © 2014 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

Effects of mid-foot contact area ratio on lower body kinetics/kinematics in sagittal plane during stair descent in women.

PubMed

Lee, Jinkyu; Hong, Yoon No Gregory; Shin, Choongsoo S

2016-07-01

The mid-foot contact area relative to the total foot contact area can facilitate foot arch structure evaluation. A stair descent motion consistently provides initial fore-foot contact and utilizes the foot arch more actively for energy absorption. The purpose of this study was to compare ankle and knee joint angle, moment, and work in sagittal plane during stair descending between low and high Mid-Foot-Contact-Area (MFCA) ratio group. The twenty-two female subjects were tested and classified into two groups (high MFCA and low MFCA) using their static MFCA ratios. The ground reaction force (GRF) and kinematics of ankle and knee joints were measured while stair descending. During the period between initial contact and the first peak in vertical GRF (early absorption phase), ankle negative work for the low MFCA ratio group was 33% higher than that for the high MFCA ratio group (p<0.05). However, ankle negative work was not significantly different between the two groups during the period between initial contact and peak dorsiflexion angle (early absorption phase+late absorption phase). The peak ankle dorsiflexion angle was smaller in the low MFCA ratio group (p<0.05). Our results suggest that strategy of energy absorption at the ankle and foot differs depending upon foot arch types classified by MFCA. The low MFCA ratio group seemed to absorb more impact energy using strain in the planar fascia during early absorption phase, whereas the high MFCA ratio group absorbed more impact energy using increased dorsiflexion during late absorption phase. Copyright © 2016 Elsevier B.V. All rights reserved.

Trunk and Lower Extremity Kinematics During Stair Descent in Women With or Without Patellofemoral Pain.

PubMed

Schwane, Brandi G; Goerger, Benjamin M; Goto, Shiho; Blackburn, J Troy; Aguilar, Alain J; Padua, Darin A

2015-07-01

There is limited evidence indicating the contribution of trunk kinematics to patellofemoral pain (PFP). A better understanding of the interaction between trunk and lower extremity kinematics in this population may provide new avenues for interventions to treat PFP. To compare trunk and lower extremity kinematics between participants with PFP and healthy controls during a stair-descent task. Cross-sectional study. Research laboratory. Twenty women with PFP (age = 22.2 ± 3.1 years, height = 164.5 ± 9.2 cm, mass = 63.5 ± 13.6 kg) and 20 healthy women (age = 21.0 ± 2.6 years, height = 164.5 ± 7.1 cm, mass = 63.8 ± 12.7 kg). Kinematics were recorded as participants performed stair descent at a controlled velocity. Three-dimensional joint displacement of the trunk, hip, and knee during the stance phase of stair descent for the affected leg was measured using a 7-camera infrared optical motion-capture system. Pretest and posttest pain were assessed using a visual analogue scale. Kinematic differences between groups were determined using independent-samples t tests. A 2 × 2 mixed-model analysis of variance (group = PFP, control; time = pretest, posttest) was used to compare knee pain. We observed greater knee internal-rotation displacement for the PFP group (12.8° ± 7.2°) as compared with the control group (8.9° ± 4.4°). No other between-groups differences were observed for the trunk, hip, or other knee variables. We observed no difference in trunk kinematics between groups but did note differences in knee internal-rotation displacement. These findings contribute to the current knowledge of altered movement in those with PFP and provide direction for exercise interventions.

Stop the escalators: using the built environment to increase usual daily activity.

PubMed

Westfall, John M; Fernald, Doug H

2010-01-01

Obesity is an epidemic in the United States. Two-thirds of the population is overweight and does not get enough exercise. Eastern cities are full of escalators that transport obese Americans to and from the subway. Walking stairs is a moderate activity requiring 3-6 metabolic equivalent tasks (METS) and burning 3.5-7 kcal/min. We determined the caloric expenditure and potential weight change of the population of one eastern city if all the subway riders walked the stairs rather than ride the escalators. There are 5,000,000 daily journeys made on the New York City Subway. Subway entrances include a stairway or escalator of approximately 25 steps. Each step up requires 0.11-0.15 kcals; each step down requires 0.05 kcals. To lose one pound requires burning 3500 kcals. We assumed each rider made a round trip so about 2.5 million individual people ride the subway each day. By walking stairs rather than riding escalators, the riders of the New York Subway would lose more than 2.6 million pounds per year. The average subway rider would lose about one pound per year. While this may sound insignificant, in one decade the average subway rider would lose 10 pounds, effectively reversing the trend in the United States of gaining 10 pounds per decade. This conservative estimate of the number of stairs ascended daily means that subway riders might lose even more weight. We believe that this novel approach might lead to other public and private efforts to increase physical activity such as elevators that only stop on even numbered floors, making stairwells more attractive and well lit, and stopping moving sidewalks. The built environment may support small, incremental changes in usual daily physical activity that can have significant impact on populations and individuals.

Invariance of wearing location of Omron-BI pedometers: a validation study.

PubMed

Zhu, Weimo; Lee, Miyoung

2010-11-01

The purpose of this study was to investigate the validity and reliability evidences of the Omron BI pedometer, which could count steps taken even when worn at different locations on the body. Forty (20 males and 20 females) adults were recruited to walk wearing 5 sets, 1 set at a time, of 10 BI pedometers during testing, 1 each at 10 different locations. For comparison, they also wore 2 Yamax Digi-Walker SW-200 pedometers and a Dynastream AMP 331 activity monitor. The subjects walked in 3 free-living conditions: a flat sidewalk, stairs, and mixed conditions. Except for a slight decrease in accuracy in the pant pocket locations, Omron BI pedometers counted steps accurately across other locations when subjects walked on the flat sidewalk, and the performance was consistent across devices and trials. When the subjects climbed up stairs, however, the absolute error % of the pant pocket locations increased significantly (P < .05) and similar or higher error rates were found in the AMP 331 and SW-200s. The Omron BI pedometer can accurately count steps when worn at various locations on the body in free-living conditions except for front pant pocket locations, especially when climbing stairs.

Management of chronic ankle pain using joint mobilization and ASTYM® treatment: a case report.

PubMed

Slaven, Emily J; Mathers, Jessie

2011-05-01

Treatment of ankle sprains predominately focuses on the acute management of this condition; less emphasis is placed on the treatment of ankle sprains in the chronic phase of recovery. Manual therapy, in the form of joint mobilization and manipulation, has been shown to be effective in the management of this condition, but the combination of joint mobilization and manipulation in tandem with ASTYM® treatment has not been explored. The purpose of this case report is to chronicle the management of a patient with chronic ankle pain who was treated with manual therapy including manipulation and ASTYM treatment. As a result of a fall down stairs 6 months previously, the patient sustained a severe ankle sprain. The soft tissue damage was accompanied by bony disruptions which warranted the patient spending 3 weeks in a walking boot. At the initial evaluation, the patient reported difficulty with descending stairs reciprocally and not being able to run more than 4 minutes on the treadmill before the pain escalated to the level that she had to stop running. After five sessions of therapy consisting of joint mobilization, manipulation and ASTYM, the patient was able to descend stairs and run 40 minutes without pain.

Pulmonary function tests in the preoperative evaluation of lung cancer surgery candidates. A review of guidelines.

PubMed

Trzaska-Sobczak, Marzena; Skoczyński, Szymon; Pierzchała, Władysław

2014-09-01

Before planned surgical treatment of lung cancer, the patient's respiratory system function should be evaluated. According to the current guidelines, the assessment should start with measurements of FEV1 (forced expiratory volume in 1 second) and DLco (carbon monoxide lung diffusion capacity). Pneumonectomy is possible when FEV1 and DLco are > 80% of the predicted value (p.v.). If either of these parameters is < 80%, an exercise test with VO2 max (oxygen consumption during maximal exercise) measurement should be performed. When VO2 max is < 35 % p.v. or < 10 ml/kg/min, resection is associated with high risk. If VO2 max is in the range of 35-75% p.v. or 10-20 ml/kg/min, the postoperative values of FEV1 and DLco (ppoFEV1, ppoDLco) should be determined. The exercise test with VO2 max measurement may be replaced with other tests such as the shuttle walk test and the stair climbing test. The distance covered during the shuttle walk test should be > 400 m. Patients considered for lobectomy should be able to climb 3 flights of stairs (12 m) and for pneumonectomy 5 flights of stairs (22 m).

Reproducibility of the kinematics and kinetics of the lower extremity during normal stair-climbing.

PubMed

Yu, B; Kienbacher, T; Growney, E S; Johnson, M E; An, K N

1997-05-01

The purpose of this study was to examine the intrasubject reproducibility of the kinematic and kinetic measures of the lower extremity during normal stair-climbing. Three-dimensional video and force-plate data were collected for three trials per subject during each of three conditions: ascending, descending, and level walking. Three-dimensional angles and moments of the ankle, knee, and hip joints were calculated. The coefficient of multiple correlation was used to determine the intrasubject reproducibility of joint angles and resultant moments. Analysis of variance with repeated measures was conducted to compare the magnitudes of the coefficients between different steps, different joints, and different joint functions. The results showed that (a) generally, the kinematic and kinetic measures of normal subjects climbing stairs were reproducible; (b) the kinetic measures during the transition steps from level walking to ascending and from descending to level walking were significantly less reproducible than those during the other steps; (c) the data from the sagittal plane were more reproducible than those from the other two planes; and (d) the kinetic measures were more reproducible than the kinematic measures, especially for abduction-adduction and internal-external rotation.

Evaluation of function, performance, and preference as transfemoral amputees transition from mechanical to microprocessor control of the prosthetic knee.

PubMed

Hafner, Brian J; Willingham, Laura L; Buell, Noelle C; Allyn, Katheryn J; Smith, Douglas G

2007-02-01

To evaluate differences in function, performance, and preference between mechanical and microprocessor prosthetic knee control technologies. A-B-A-B reversal design. Home, community, and laboratory environments. Twenty-one unilateral, transfemoral amputees. Mechanical control prosthetic knee versus microprocessor control prosthetic knee (Otto Bock C-Leg). Stair rating, hill rating and time, obstacle course time, divided attention task accuracy and time, Amputee Mobility Predictor score, step activity, Prosthesis Evaluation Questionnaire score, Medical Outcomes Study 36-Item Short-Form Health Survey score, self-reported frequency of stumbles and falls, and self-reported concentration required for ambulation. Stair descent score, hill descent time, and hill sound-side step length showed significant (P<.01) improvement with the C-Leg. Users reported a significant (P<.05) decrease in frequency of stumbles and falls, frustration with falling, and difficulty in multitasking while using the microprocessor knee. Subject satisfaction with the C-Leg was significantly (P<.001) greater than the mechanical control prosthesis. The study population showed improved performance when negotiating stairs and hills, reduced frequency of stumbling and falling, and a preference for the microprocessor control C-Leg as compared with the mechanical control prosthetic knee.

Promoting physical activity: fertile ground for rehabilitation psychology.

PubMed

Uswatte, Gitendra

2013-02-01

Comments on the article by Schmacher et al. (see record 2013-06066-009). Readers of Rehabilitation Psychology might be surprised, or maybe even alarmed, to find an article on promoting physical activity in able-bodied people between the covers of their latest issue. This commentary contends that this area of research and practice might be one into which rehabilitation psychologists want to venture. Schumacher and coworkers describe a field test (N = 216) of a token system for reinforcing stair taking. The setting was an eight-story office building housing a single company in a midsized city in the southeastern United States. Schumacher et al. report an increase from 39 stair transactions per day by all study participants in the 6 months before implementation of the intervention to 301 transactions in the 6 months after the implementation of the intervention, which represents a 600% increase. The cost of the intervention was only $17 per person. Although replication of these results in a study with additional sources of control would increase confidence in the validity of the findings, the size of the gains in stair taking, the number of participants in the study, the length of the baseline and implementation periods, and the objective measurement of outcome warrant attention.

Physiologic responses to forward and retrograde simulated stair stepping.

PubMed

Ryan, P T; Plowman, S A; Ball, T E; Looney, M A

1994-07-01

This study compared the physiologic responses to forward and retrograde simulated stair stepping on the StairMaster 4000 PT. Twenty male subjects (mean age 23.65 +/- 1.63 years) volunteered for this study. Subjects completed a practice trial of 6 minutes of both forward and retrograde stepping at Level 5. Each experimental trial was divided into four 3-minute stages: Level 3, Level 5, Level 7, and Level 9. Heart rate, blood pressure, and rating of perceived exertion (RPE) were recorded during the second minute of each stage. Expired gases were analyzed and averaged over the last 2 minutes of each stage. Caloric expenditure and delta efficiency were later calculated. Data were analyzed using a 2 x 4 ANOVA (direction by level) and 2 x 3 ANOVA (for delta efficiency). Compared to forward responses, retrograde heart rates were significantly higher at Levels 7 and 9 (p < 0.01). Retrograde responses for RPE, metabolic equivalents (METS), and caloric expenditure were significantly higher at (p < 0.01) Levels 5, 7, and 9 when compared to forward responses. However, the results of this study show that these differences between forward and retrograde stepping are not practically meaningful.

Validity and reliability of the Omron HJ-303 tri-axial accelerometer-based pedometer.

PubMed

Steeves, Jeremy A; Tyo, Brian M; Connolly, Christopher P; Gregory, Douglas A; Stark, Nyle A; Bassett, David R

2011-09-01

This study compared the validity of a new Omron HJ-303 piezoelectric pedometer and 2 other pedometers (Sportline Traq and Yamax SW200). To examine the effect of speed, 60 subjects walked on a treadmill at 2, 3, and 4 mph. Twenty subjects also ran at 6, 7, and 8 mph. To test lifestyle activities, 60 subjects performed front-back-side-side stepping, elliptical machine and stair climbing/descending. Twenty others performed ballroom dancing. Sixty participants completed 5 100-step trials while wearing 5 different sets of the devices tested device reliability. Actual steps were determined using a hand tally counter. Significant differences existed among pedometers (P < .05). For walking, the Omron pedometers were the most valid. The Sportline overestimated and the Yamax underestimated steps (P < .05). Worn on the waist or in the backpack, the Omron device and Sportline were valid for running. The Omron was valid for 3 activities (elliptical machine, ascending and descending stairs). The Sportline overestimated all of these activities, and Yamax was only valid for descending stairs. The Omron andYamax were both valid and reliable in the 100-step trials. The Omron HJ-303, worn on the waist, appeared to be the most valid of the 3 pedometers.

Understanding the etiology of the posteromedial tibial stress fracture.

PubMed

Milgrom, Charles; Burr, David B; Finestone, Aharon S; Voloshin, Arkady

2015-09-01

Previous human in vivo tibial strain measurements from surface strain gauges during vigorous activities were found to be below the threshold value of repetitive cyclical loading at 2500 microstrain in tension necessary to reduce the fatigue life of bone, based on ex vivo studies. Therefore it has been hypothesized that an intermediate bone remodeling response might play a role in the development of tibial stress fractures. In young adults tibial stress fractures are usually oblique, suggesting that they are the result of failure under shear strain. Strains were measured using surface mounted unstacked 45° rosette strain gauges on the posterior aspect of the flat medial cortex just below the tibial midshaft, in a 48year old male subject while performing vertical jumps, staircase jumps and running up and down stadium stairs. Shear strains approaching 5000 microstrain were recorded during stair jumping and vertical standing jumps. Shear strains above 1250 microstrain were recorded during runs up and down stadium steps. Based on predictions from ex vivo studies, stair and vertical jumping tibial shear strain in the test subject was high enough to potentially produce tibial stress fracture subsequent to repetitive cyclic loading without necessarily requiring an intermediate remodeling response to microdamage. Copyright © 2015 Elsevier Inc. All rights reserved.

Subject-Specific Modeling of Muscle Force and Knee Contact in Total Knee Arthroplasty

PubMed Central

Navacchia, Alessandro; Rullkoetter, Paul J.; Schütz, Pascal; List, Renate B.; Fitzpatrick, Clare K.; Shelburne, Kevin B.

2017-01-01

Understanding the mechanical loading environment and resulting joint mechanics for activities of daily living in total knee arthroplasty is essential to continuous improvement in implant design. Although survivorship of these devices is good, a substantial number of patients report dissatisfaction with the outcome of their procedure. Knowledge of in vivo kinematics and joint loading will enable improvement in preclinical assessment and refinement of implant geometry. The purpose of this investigation was to describe the mechanics of total knee arthroplasty during a variety of activities of daily living (gait, walking down stairs, and chair rise/sit). Estimates of muscle forces, tibial contact load, location, and pressure distribution was performed through a combination of mobile fluoroscopy data collection, musculoskeletal modeling, and finite element simulation. For the activities evaluated, joint compressive load was greatest during walking down stairs; however, the highest contact pressure occurred during chair rise/sit. The joint contact moment in the frontal plane was mainly varus for gait and walking down stairs, while it was valgus during chair rise/sit. Excursion of the center of pressure on the tibial component was similar during each activity and between the medial and lateral sides. The main determinants of center of pressure location were internal–external rotation, joint load, and tibial insert conformity. PMID:26792665

The detailed measurement of foot clearance by young adults during stair descent.

PubMed

Telonio, A; Blanchet, S; Maganaris, C N; Baltzopoulos, V; McFadyen, B J

2013-04-26

Foot clearance is an important variable for understanding safe stair negotiation, but few studies have provided detailed measures of it. This paper presents a new method to calculate minimal shoe clearance during stair descent and compares it to previous literature. Seventeen healthy young subjects descended a five step staircase with step treads of 300 mm and step heights of 188 mm. Kinematic data were collected with an Optotrak system (model 3020) and three non-colinear infrared markers on the feet. Ninety points were digitized on the foot sole prior to data collection using a 6 marker probe and related to the triad of markers on the foot. The foot sole was reconstructed using the Matlab (version 7.0) "meshgrid" function and minimal distance to each step edge was calculated for the heel, toe and foot sole. Results showed significant differences in minimum clearance between sole, heel and toe, with the shoe sole being the closest and the toe the furthest. While the hind foot sole was closest for 69% of the time, the actual minimum clearance point on the sole did vary across subjects and staircase steps. This new method, and the findings on healthy young subjects, can be applied to future studies of other populations and staircase dimensions. Copyright © 2013 Elsevier Ltd. All rights reserved.

Diffusion-weighted MR imaging of the liver at 3.0 Tesla using TRacking Only Navigator echo (TRON): a feasibility study.

PubMed

Ivancevic, Marko K; Kwee, Thomas C; Takahara, Taro; Ogino, Tetsuo; Hussain, Hero K; Liu, Peter S; Chenevert, Thomas L

2009-11-01

To assess the feasibility of TRacking Only Navigator echo (TRON) for diffusion-weighted magnetic resonance imaging (DWI) of the liver at 3.0T. Ten volunteers underwent TRON, respiratory triggered, and free breathing DWI of the liver at 3.0 Tesla (T). Scan times were measured. Image sharpness, degree of stair-step and stripe artifacts for the three methods were assessed by two observers. Mean scan times of TRON and respiratory triggered DWI relative to free breathing DWI were 34% and 145% longer respectively. In four of eight comparisons (two observers, two b-values, two slice orientations), TRON DWI image sharpness was significantly better than free breathing DWI, but inferior to respiratory triggered DWI. In two of four comparisons (two observers, two b-values), degree of stair-step artifacts in TRON DWI was significantly lower than in respiratory triggered DWI. Degree of stripe artifacts between the three methods was not significantly different. DWI of the liver at 3.0T using TRON is feasible. Image sharpness in TRON DWI is superior to that in free breathing DWI. Although image sharpness of respiratory triggered DWI is still better, TRON DWI requires less scan time and reduces stair-step artifacts.

Detection of Prosthetic Knee Movement Phases via In-Socket Sensors: A Feasibility Study

PubMed Central

El-Sayed, Amr M.; Tan, Kenneth Y. S.; Abu Osman, Noor Azuan

2015-01-01

This paper presents an approach of identifying prosthetic knee movements through pattern recognition of mechanical responses at the internal socket's wall. A quadrilateral double socket was custom made and instrumented with two force sensing resistors (FSR) attached to specific anterior and posterior sites of the socket's wall. A second setup was established by attaching three piezoelectric sensors at the anterior distal, anterior proximal, and posterior sites. Gait cycle and locomotion movements such as stair ascent and sit to stand were adopted to characterize the validity of the technique. FSR and piezoelectric outputs were measured with reference to the knee angle during each phase. Piezoelectric sensors could identify the movement of midswing and terminal swing, pre-full standing, pull-up at gait, sit to stand, and stair ascent. In contrast, FSR could estimate the gait cycle stance and swing phases and identify the pre-full standing at sit to stand. FSR showed less variation during sit to stand and stair ascent to sensitively represent the different movement states. The study highlighted the capacity of using in-socket sensors for knee movement identification. In addition, it validated the efficacy of the system and warrants further investigation with more amputee subjects and different sockets types. PMID:25945365

Duration and frequency of every day activities in total hip patients.

PubMed

Morlock, M; Schneider, E; Bluhm, A; Vollmer, M; Bergmann, G; Müller, V; Honl, M

2001-07-01

Little knowledge about frequency and duration of daily activities in patients after total hip arthroplasty is available. Such information is required for the definition of realistic load collectives for pre-clinical testing of prostheses. It could also be helpful for the quantitative evaluation of surgery outcome with different prosthesis types. The purpose of this study was to develop and apply a system for the determination of frequency and duration of patient activities in their habitual environment and to compare the results to a clinical outcome score (Harris hip score).A portable activity monitoring system (weight 1.6 kg including batteries) was designed using a Palm top computer, 2 inclination sensors for the thigh and calf and one goniometer positioned at the knee joint. An algorithm was developed to identify frequency and duration of the activities lying, sitting, standing, walking and stair climbing from the signals of the 3 sensors. 42 patients participated in the study and were equipped with the system in the morning at their home. Datasets of 31 patients (age 62.5+/-11.5 y) covered more than 6h (9.8 +/- 1.6 h) and were included in the analysis. Prosthesis specific data as well as the Harris hip score were collected. The most frequent patient activity was sitting (44.3% of the time), followed by standing (24.5%), walking (10.2%), lying (5.8%) and stair climbing (0.4%). The median number of steps/stairs was 6048/164. The number of step cycles representing one year in vivo use should, consequently, be increased to 1.1 million. The Harris hip score (91.4 +/- 9.8) correlated significantly with the number of stairs (r(2) = 0.26, p = 0.003) and showed a positive tendency with the number of steps per day. No differences in activity levels between prosthesis specific factors were found.

A functional comparison of conventional knee-ankle-foot orthoses and a microprocessor-controlled leg orthosis system based on biomechanical parameters.

PubMed

Schmalz, Thomas; Pröbsting, Eva; Auberger, Roland; Siewert, Gordon

2016-04-01

The microprocessor-controlled leg orthosis C-Brace enables patients with paretic or paralysed lower limb muscles to use dampened knee flexion under weight-bearing and speed-adapted control of the swing phase. The objective of the present study was to investigate the new technical functions of the C-Brace orthosis, based on biomechanical parameters. The study enrolled six patients. The C-Brace orthosis is compared with conventional leg orthoses (four stance control orthoses, two locked knee-ankle-foot orthoses) using biomechanical parameters of level walking, descending ramps and descending stairs. Ground reaction forces, joint moments and kinematic parameters were measured for level walking as well as ascending and descending ramps and stairs. With the C-Brace, a nearly natural stance phase knee flexion was measured during level walking (mean value 11° ± 5.6°). The maximum swing phase knee flexion angle of the C-Brace approached the normal value of 65° more closely than the stance control orthoses (66° ± 8.5° vs 74° ± 6.4°). No significant differences in the joint moments were found between the C-Brace and stance control orthosis conditions. In contrast to the conventional orthoses, all patients were able to ambulate ramps and stairs using a step-over-step technique with C-Brace (flexion angle 64.6° ± 8.2° and 70.5° ± 12.4°). The results show that the functions of the C-Brace for situation-dependent knee flexion under weight bearing have been used by patients with a high level of confidence. The functional benefits of the C-Brace in comparison with the conventional orthotic mechanisms could be demonstrated most clearly for descending ramps and stairs. The C-Brace orthosis is able to combine improved orthotic function with sustained orthotic safety. © The International Society for Prosthetics and Orthotics 2014.

Kinematics of anterior cruciate ligament-deficient knees in a Chinese population during stair ascent.

PubMed

Zhao, Chang; Lin, Chuangxin; Wang, Wenhao; Zeng, Chun; Fang, Hang; Pan, Jianying; Cai, Daozhang

2016-08-08

The purpose of this study was to measure the tibiofemoral kinematics of anterior cruciate ligament (ACL) deficiency in a Chinese population and compare the kinematics with published data about a Caucasian population. Unilateral knees of 18 Chinese ACL-deficient (ACL-D) subjects were studied while subjects ascended stairs. Kinematic alteration was compared between ACL-D knees and contralateral ACL-intact (ACL-I) knees. The kinematic alteration of ACL deficiency was also compared between the Chinese population and published data about a Caucasian population. A statistical difference was found in the three-dimensional rotations between ACL-D and ACL-I knees. In the sagittal plane, ACL-I knees had a larger flexion angle than ACL-D knees during 40 to 50 % of the activity during stair ascent (P < 0.027) and throughout the gait cycle. A significant difference in rotational motion between ACL-D and ACL-I knees was also observed in the frontal plane during 40 to 60 % (P < 0.017) of the activity and in the transverse plane during 70 to 80 % (P < 0.028) of the activity. A greater tibial varus was demonstrated in the Chinese population while the published data revealed external tibial rotation and a statistical difference in translation in the Caucasian population. ACL-D knees show different kinematics than ACL-I knees in the Chinese population. ACL-I knees had a larger flexion angle than ACL-D knees in the middle stage of the activity during stair ascent. A significant difference in rotational motion between ACL-D and ACL-I knees was also observed in the frontal plane during the middle phase and in the transverse plane during the terminal phase of the activity. A greater tibial varus was demonstrated in the Caucasian population while the published data revealed external tibial rotation and a statistical difference in translation in the Caucasian population.

The Influence of Task Complexity on Knee Joint Kinetics Following ACL Reconstruction

PubMed Central

Schroeder, Megan J.; Krishnan, Chandramouli; Dhaher, Yasin Y.

2015-01-01

Background Previous research indicates that subjects with anterior cruciate ligament reconstruction exhibit abnormal knee joint movement patterns during functional activities like walking. While the sagittal plane mechanics have been studied extensively, less is known about the secondary planes, specifically with regard to more demanding tasks. This study explored the influence of task complexity on functional joint mechanics in the context of graft-specific surgeries. Methods In 25 participants (10 hamstring tendon graft, 6 patellar tendon graft, 9 matched controls), three-dimensional joint torques were calculated using a standard inverse dynamics approach during level walking and stair descent. The stair descent task was separated into two functionally different sub-tasks—step-to-floor and step-to-step. The differences in external knee moment profiles were compared between groups; paired differences between the reconstructed and non-reconstructed knees were also assessed. Findings The reconstructed knees, irrespective of graft type, typically exhibited significantly lower peak knee flexion moments compared to control knees during stair descent, with the differences more pronounced in the step-to-step task. Frontal plane adduction torque deficits were graft-specific and limited to the hamstring tendon knees during the step-to-step task. Internal rotation torque deficits were also primarily limited to the hamstring tendon graft group during stair descent. Collectively, these results suggest that task complexity was a primary driver of differences in joint mechanics between anterior cruciate ligament reconstructed individuals and controls, and such differences were more pronounced in individuals with hamstring tendon grafts. Interpretation The mechanical environment experienced in the cartilage during repetitive, cyclical tasks such as walking and other activities of daily living has been argued to contribute to the development of degenerative changes to the joint and ultimately osteoarthritis. Given the task-specific and graft-specific differences in joint mechanics detected in this study, care should be taken during the rehabilitation process to mitigate these changes. PMID:26101055

Stop the escalators: using the built environment to increase usual daily activity

PubMed Central

Westfall, John M; Fernald, Doug H

2010-01-01

Background Obesity is an epidemic in the United States. Two-thirds of the population is overweight and does not get enough exercise. Eastern cities are full of escalators that transport obese Americans to and from the subway. Walking stairs is a moderate activity requiring 3–6 metabolic equivalent tasks (METS) and burning 3.5–7 kcal/min. We determined the caloric expenditure and potential weight change of the population of one eastern city if all the subway riders walked the stairs rather than ride the escalators. Methods There are 5,000,000 daily journeys made on the New York City Subway. Subway entrances include a stairway or escalator of approximately 25 steps. Each step up requires 0.11–0.15 kcals; each step down requires 0.05 kcals. To lose one pound requires burning 3500 kcals. We assumed each rider made a round trip so about 2.5 million individual people ride the subway each day. Results By walking stairs rather than riding escalators, the riders of the New York Subway would lose more than 2.6 million pounds per year. Discussion The average subway rider would lose about one pound per year. While this may sound insignificant, in one decade the average subway rider would lose 10 pounds, effectively reversing the trend in the United States of gaining 10 pounds per decade. This conservative estimate of the number of stairs ascended daily means that subway riders might lose even more weight. We believe that this novel approach might lead to other public and private efforts to increase physical activity such as elevators that only stop on even numbered floors, making stairwells more attractive and well lit, and stopping moving sidewalks. The built environment may support small, incremental changes in usual daily physical activity that can have significant impact on populations and individuals. PMID:27774003

Short-term effects of customized arch support insoles on symptomatic flexible flatfoot in children: A randomized controlled trial.

PubMed

Hsieh, Ru-Lan; Peng, Hui-Ling; Lee, Wen-Chung

2018-05-01

Limited evidence is available regarding the effects of insoles on pediatric flexible flatfoot because of the heterogeneity and low methodological quality of previous studies. The purpose of this prospective trial is to examine the short-term effects of customized arch support insoles on symptomatic flexible flatfoot in children by using the International Classification of Functioning, randomized controlled Disability, and Health (ICF) framework. This study was conducted in a rehabilitation outpatient clinic of a teaching hospital. Fifty-two children with symptomatic flexible flatfoot were included. The children in the treatment group wore customized arch support insoles for 12 weeks, whereas those in the control group did not wear the insoles. Both clinical and radiographic measurements, including the navicular drop, foot posture index, Beighton hypermobility score, talonavicular coverage angle, calcaneal inclination angle, and calcaneal-first metatarsal angle, were used for diagnosing flexible flatfoot. Physical activity (10-m normal and fast walking, stair ascent, stair descent, and chair rising), physical function, and psychometric properties (Pediatric Outcome Data Collection Instrument and Pediatric Quality of Life Inventory) were evaluated at the baseline and 12 weeks after the intervention. Compared with the control group, the treatment group exhibited significant improvement in pain/comfort (P = .048), physical health (P = .035), stair ascent time (P = .015), upper extremity and physical function (P = .016), and transfer and basic mobility (P = .042) during the intervention period. Children with flexible flatfoot who wore customized arch support insoles for 12 weeks exhibited significantly improved pain/comfort, physical health, stair ascent time, upper extremity and physical function, and transfer and basic mobility. These variables belong to the domains of body functions and structures and activity and participation in the ICF framework. However, because the groups were not comparable, additional studies with larger sample sizes should be conducted.

42 CFR 409.44 - Skilled services requirements.

Code of Federal Regulations, 2011 CFR

2011-10-01

... welfare of beneficiaries (for example, exercises to promote overall fitness) do not constitute physical... eating, swallowing, bathing, dressing, toileting, walking, climbing stairs, or using assistive devices...

Knee Joint Loads and Surrounding Muscle Forces during Stair Ascent in Patients with Total Knee Replacement

PubMed Central

Rasnick, Robert; Standifird, Tyler; Reinbolt, Jeffrey A.; Cates, Harold E.

2016-01-01

Total knee replacement (TKR) is commonly used to correct end-stage knee osteoarthritis. Unfortunately, difficulty with stair climbing often persists and prolongs the challenges of TKR patents. Complete understanding of loading at the knee is of great interest in order to aid patient populations, implant manufacturers, rehabilitation, and future healthcare research. Musculoskeletal modeling and simulation approximates joint loading and corresponding muscle forces during a movement. The purpose of this study was to determine if knee joint loadings following TKR are recovered to the level of healthy individuals, and determine the differences in muscle forces causing those loadings. Data from five healthy and five TKR patients were selected for musculoskeletal simulation. Variables of interest included knee joint reaction forces (JRF) and the corresponding muscle forces. A paired samples t-test was used to detect differences between groups for each variable of interest (p<0.05). No differences were observed for peak joint compressive forces between groups. Some muscle force compensatory strategies appear to be present in both the loading and push-off phases. Evidence from knee extension moment and muscle forces during the loading response phase indicates the presence of deficits in TKR in quadriceps muscle force production during stair ascent. This result combined with greater flexor muscle forces resulted in similar compressive JRF during loading response between groups. PMID:27258086

Stairs and Doors Recognition as Natural Landmarks Based on Clouds of 3D Edge-Points from RGB-D Sensors for Mobile Robot Localization.

PubMed

Souto, Leonardo A V; Castro, André; Gonçalves, Luiz Marcos Garcia; Nascimento, Tiago P

2017-08-08

Natural landmarks are the main features in the next step of the research in localization of mobile robot platforms. The identification and recognition of these landmarks are crucial to better localize a robot. To help solving this problem, this work proposes an approach for the identification and recognition of natural marks included in the environment using images from RGB-D (Red, Green, Blue, Depth) sensors. In the identification step, a structural analysis of the natural landmarks that are present in the environment is performed. The extraction of edge points of these landmarks is done using the 3D point cloud obtained from the RGB-D sensor. These edge points are smoothed through the S l 0 algorithm, which minimizes the standard deviation of the normals at each point. Then, the second step of the proposed algorithm begins, which is the proper recognition of the natural landmarks. This recognition step is done as a real-time algorithm that extracts the points referring to the filtered edges and determines to which structure they belong to in the current scenario: stairs or doors. Finally, the geometrical characteristics that are intrinsic to the doors and stairs are identified. The approach proposed here has been validated with real robot experiments. The performed tests verify the efficacy of our proposed approach.

Stairs and Doors Recognition as Natural Landmarks Based on Clouds of 3D Edge-Points from RGB-D Sensors for Mobile Robot Localization†

PubMed Central

Castro, André; Nascimento, Tiago P.

2017-01-01

Natural landmarks are the main features in the next step of the research in localization of mobile robot platforms. The identification and recognition of these landmarks are crucial to better localize a robot. To help solving this problem, this work proposes an approach for the identification and recognition of natural marks included in the environment using images from RGB-D (Red, Green, Blue, Depth) sensors. In the identification step, a structural analysis of the natural landmarks that are present in the environment is performed. The extraction of edge points of these landmarks is done using the 3D point cloud obtained from the RGB-D sensor. These edge points are smoothed through the Sl0 algorithm, which minimizes the standard deviation of the normals at each point. Then, the second step of the proposed algorithm begins, which is the proper recognition of the natural landmarks. This recognition step is done as a real-time algorithm that extracts the points referring to the filtered edges and determines to which structure they belong to in the current scenario: stairs or doors. Finally, the geometrical characteristics that are intrinsic to the doors and stairs are identified. The approach proposed here has been validated with real robot experiments. The performed tests verify the efficacy of our proposed approach. PMID:28786925

Contextual barriers to lifestyle physical activity interventions in Hong Kong.

PubMed

Eves, Frank F; Masters, Rich S W; McManus, Alison; Leung, Moon; Wong, Peggy; White, Mike J

2008-05-01

Increased lifestyle physical activity, for instance, use of active transport, is a current public health target. Active transport interventions that target stair climbing are consistently successful in English-speaking populations yet unsuccessful in Hong Kong. We report two further studies on active transport in the Hong Kong Chinese. Pedestrians on a mass transit escalator system (study 1) and in an air-conditioned shopping mall (study 2) were encouraged to take the stairs for their cardiovascular health by point-of-choice prompts. Observers coded sex, age, and walking on the mass transit system, with the additional variables of presence of children and bags coded in the shopping mall. In the first study, a 1-wk baseline was followed by 4 wk of intervention (N = 76,710) whereas in the second study (shopping mall) a 2-wk baseline was followed by a 2-wk intervention period (N = 18,257). A small but significant increase in stair climbing (+0.29%) on the mass transit system contrasted with no significant changes in the shopping mall (+0.09%). The active transport of walking on the mass transit system was reduced at higher rates of humidity and temperature, with steeper slopes for the effects of climate variables in men than in women. These studies confirm that lifestyle physical activity interventions do not have universal application. The context in which the behavior occurs (e.g., climate) may act as a barrier to active transport.

Health-related physical fitness measures: reference values and reference equations for use in clinical practice.

PubMed

Tveter, Anne Therese; Dagfinrud, Hanne; Moseng, Tuva; Holm, Inger

2014-07-01

To provide reference values and reference equations for frequently used clinical field tests of health-related physical fitness for use in clinical practice. Cross-sectional design. General community. Convenience sample of volunteers (N=370) between 18 and 90 years of age were recruited from a wide range of settings (ie, work sites, schools, community centers for older adults) and different geographic locations (ie, urban, suburban, rural) in southeastern Norway. Not applicable. The participants conducted 5 clinical field tests (6-minute walk test, stair test, 30-second sit-to-stand test, handgrip test, fingertip-to-floor test). The results of the field tests showed that performance remained unchanged until approximately 50 years of age; after that, performance deteriorated with increasing age. Grip strength (79%), meters walked in 6 minutes (60%), and seconds used on the stair test (59%) could be well predicted by age, sex, height, and weight in participants ≥50 years of age, whereas the performance on all tests was less well predicted in participants <50 years of age. The reference values and reference equations provided in this study may increase the applicability and interpretability of the 6-minute walk test, stair test, 30-second sit-to-stand test, handgrip test, and fingertip-to-floor test in clinical practice. Copyright © 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Altered EMG patterns in diabetic neuropathic and not neuropathic patients during step ascending and descending.

PubMed

Spolaor, Fabiola; Sawacha, Zimi; Guarneri, Gabriella; Del Din, Silvia; Avogaro, Angelo; Cobelli, Claudio

2016-12-01

Diabetic peripheral neuropathy (DPN) causes motor control alterations during daily life activities. Tripping during walking or stair climbing is the predominant cause of falls in the elderly subjects with DPN and without (NoDPN). Surface Electromyography (sEMG) has been shown to be a valid tool for detecting alterations of motor functions in subjects with DPN. This study aims at investigating the presence of functional alterations in diabetic subjects during stair climbing and at exploring the relationship between altered muscle activation and temporal parameter. Lower limb muscle activities, temporal parameters and speed were evaluated in 50 subjects (10 controls, 20 with DPN, 20 without DPN), while climbing up and down a stair, using sEMG, three-dimentional motion capture and force plates. Magnitude and timing of sEMG linear envelopes peaks were extracted. Level walking was used as reference condition for the comparison with step negotiation. sEMG, speed and temporal parameters revealed significant differences among all groups of patients. Results showed an association between earlier activation of lower limb muscles and reduced speed in subjects with DPN. Speed and temporal parameters significantly correlated with sEMG (p<0.05). The findings of this study are encouraging and could be used to improve rehabilitation programs aiming at reducing falls risk in diabetic subjects. Copyright © 2016 Elsevier Ltd. All rights reserved.

Detection of Gait Modes Using an Artificial Neural Network during Walking with a Powered Ankle-Foot Orthosis

PubMed Central

2016-01-01

This paper presents an algorithm, for use with a Portable Powered Ankle-Foot Orthosis (i.e., PPAFO) that can automatically detect changes in gait modes (level ground, ascent and descent of stairs or ramps), thus allowing for appropriate ankle actuation control during swing phase. An artificial neural network (ANN) algorithm used input signals from an inertial measurement unit and foot switches, that is, vertical velocity and segment angle of the foot. Output from the ANN was filtered and adjusted to generate a final data set used to classify different gait modes. Five healthy male subjects walked with the PPAFO on the right leg for two test scenarios (walking over level ground and up and down stairs or a ramp; three trials per scenario). Success rate was quantified by the number of correctly classified steps with respect to the total number of steps. The results indicated that the proposed algorithm's success rate was high (99.3%, 100%, and 98.3% for level, ascent, and descent modes in the stairs scenario, respectively; 98.9%, 97.8%, and 100% in the ramp scenario). The proposed algorithm continuously detected each step's gait mode with faster timing and higher accuracy compared to a previous algorithm that used a decision tree based on maximizing the reliability of the mode recognition. PMID:28070188

Construction and optical properties of infinite Cd and finite Cu molecules stairs

NASA Astrophysics Data System (ADS)

Zhao, Qiang; Mao, Wutao; Shen, Zhi; Wang, Qinghong; Zhou, Qian

2017-02-01

Two coordination complexes, namely [(hpdq)(pta)Cd]n (1) and [(pptp)(pta)Cu2Cl] (2) have been synthesized by solvothermal method based on two polypyridyl ligands, 2,3,6,7,10,11-hexakis- (2-pyridyl)dipyrazino[2,3-f:2‧,3‧-h]quinoxaline) (hpdq), 4‧-(4- (3H-pyrrol-3-yl)phenyl)- 2,2‧:6‧,2″- terpyridine (pptp) and auxiliary ligand p-phthalic acid (pta), respectively. Single crystal x-ray diffraction analyses reveal that complexes 1 and 2 assembled based on distinct asymmetric unit comprising one and two respective polypyridyl ligands but one Cd(II) and two Cu(I)ions, respectively. Among them, The asymmetric units in 1 was extended to one dimensional chain via the link of auxiliary ligand pta, just like infinite layers of stairs that connected by cadmium ions as the node. While that in 2 to Zero dimensional tetranuclear structure via the link of auxiliary ligand pta, just like finite four layers of stairs that Copper ion as the node connection. Furthermore, solid fluorescence spectra properties of two complexes were also investigated, and the result shows the fluorescence intensity of complex 1 is stronger than that of the hpdq ligand, but the fluorescence intensity of complex 2 is weaker than that of the pptp ligand. CCDC number of 1and 2 are 1483301 and 1483302.

Effects of lighting illuminance levels on stair negotiation performance in individuals with visual impairment.

PubMed

Shaheen, Aliah F; Sourlas, Alexandros; Horton, Khim; McLean, Christopher; Ewins, David; Gould, David; Ghoussayni, Salim

2018-04-01

Stair-related falls of older people cause a substantial financial and social burden. Deterioration of the visual system amongst other factors put older people at a high risk of falling. Improved lighting is often recommended. The aim of this study was to investigate the effect of lighting illuminance on stair negotiation performance in older individuals with visual impairment. Eleven participants aged 60 or over with a vision of 6/18 or worse ascended and descended a staircase under: 50 lx, 100 lx, 200 lx, 300 lx and distributed 200 lx lighting. A motion capture system was used to measure movements of the lower limb. Clearance, clearance variability, temporal and spatial parameters and joint/segment kinematics were computed. There was no effect on clearance or clearance variability. Participants had lower speed, cadence, increased cycle time and stance time in the 50 lx compared to 300 lx and distributed 200 lx lighting in descent. The minimum hip angle in ascent was increased in the 200 lx lighting. Clearance was found to be moderately correlated with balance scores. Individuals with visual impairment adopt precautionary gait in dim lighting conditions. This does not always result in improvements in the parameters associated with risk of falling (e.g. clearance). Copyright © 2018 Elsevier Ltd. All rights reserved.

Exercise Habit

MedlinePlus

... and lungs. Examples of aerobic exercise include walking, hiking, running, aerobic dance, biking, rowing, swimming, and cross- ... Examples of weight-bearing exercise include walking, yoga, hiking, climbing stairs, playing tennis, dancing, and strength training. ...

Hip pain

MedlinePlus

... from a chair, walking, climbing stairs, and driving Hamstring strain Iliotibial band syndrome Hip flexor strain Hip ... and cool down afterward. Stretch your quadriceps and hamstrings. Avoid running straight down hills. Walk down instead. ...

2. Historic American Buildings Survey Nathaniel R. Ewan, Photographer August ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. Historic American Buildings Survey Nathaniel R. Ewan, Photographer August 10, 1938 INTERIOR - STAIR AND CUPBOARD DETAIL - General Clinton Headquarters, Evesboro Road, Evesboro, Burlington County, NJ

Feasibility study of current pulse induced 2-bit/4-state multilevel programming in phase-change memory

NASA Astrophysics Data System (ADS)

Liu, Yan; Fan, Xi; Chen, Houpeng; Wang, Yueqing; Liu, Bo; Song, Zhitang; Feng, Songlin

2017-08-01

In this brief, multilevel data storage for phase-change memory (PCM) has attracted more attention in the memory market to implement high capacity memory system and reduce cost-per-bit. In this work, we present a universal programing method of SET stair-case current pulse in PCM cells, which can exploit the optimum programing scheme to achieve 2-bit/ 4state resistance-level with equal logarithm interval. SET stair-case waveform can be optimized by TCAD real time simulation to realize multilevel data storage efficiently in an arbitrary phase change material. Experimental results from 1 k-bit PCM test-chip have validated the proposed multilevel programing scheme. This multilevel programming scheme has improved the information storage density, robustness of resistance-level, energy efficient and avoiding process complexity.

The science behind codes and standards for safe walkways: changes in level, stairways, stair handrails and slip resistance.

PubMed

Nemire, Kenneth; Johnson, Daniel A; Vidal, Keith

2016-01-01

Walkway codes and standards are often created through consensus by committees based on a number of factors, including historical precedence, common practice, cost, and empirical data. The authors maintain that in the formulation of codes and standards that impact pedestrian safety, the results of pertinent scientific research should be given significant weight. This article examines many elements of common walkway codes and standards related to changes in level, stairways, stair handrails, and slip resistance. It identifies which portions are based on or supported by empirical data; and which could benefit from additional scientific research. This article identifies areas in which additional research, codes, and standards may be beneficial to enhance pedestrian safety. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Muscles do more positive than negative work in human locomotion

PubMed Central

DeVita, Paul; Helseth, Joseph; Hortobagyi, Tibor

2008-01-01

Summary Muscle work during level walking and ascent and descent ramp and stairway walking was assessed in order to explore the proposition that muscles perform more positive than negative work during these locomotion tasks. Thirty four healthy human adults were tested while maintaining a constant average walking velocity in the five gait conditions. Ground reaction force and sagittal plane kinematic data were obtained during the stance phases of these gaits and used in inverse dynamic analyses to calculate joint torques and powers at the hip, knee and ankle. Muscle work was derived as the area under the joint power vs time curves and was partitioned into positive, negative and net components. Dependent t-tests were used to compare positive and negative work in level walking and net joint work between ascent and descent gaits on the ramp and stairs (P<0.010). Total negative and positive work in level walking was −34 J and 50 J, respectively, with the difference in magnitude being statistically significant (P<0.001). Level walking was therefore performed with 16 J of net positive muscle work per step. The magnitude of the net work in ramp ascent was 25% greater than the magnitude of net work in ramp descent (89 vs −71 J m−1, P<0.010). Similarly, the magnitude of the net work in stair ascent was 43% greater than the magnitude of net work in stair descent (107 vs −75 J step−1, P<0.000). We identified three potential causes for the reduced negative vs positive work in these locomotion tasks: (1) the larger magnitude of the accelerations induced by the larger ground reaction forces in descending compared to ascending gaits elicited greater energy dissipation in non-muscular tissues, (2) the ground reaction force vector was directed closer to the joint centers in ramp and stair descent compared to ascent, which reduced the load on the muscular tissues and their energy dissipating response, and (3) despite the need to produce negative muscle work in descending gaits, both ramp and stair descent also had positive muscle work to propel the lower extremity upward and forward into the swing phase movement trajectory. We used these data to formulate two novel hypotheses about human locomotion. First, level walking requires muscles to generate a net positive amount of work per gait cycle to overcome energy losses by other tissues. Second, skeletal muscles generate more mechanical energy in gait tasks that raise the center of mass compared to the mechanical energy they dissipate in gait tasks that lower the center of mass, despite equivalent changes in total mechanical energy. PMID:17872990

Muscles do more positive than negative work in human locomotion.

PubMed

DeVita, Paul; Helseth, Joseph; Hortobagyi, Tibor

2007-10-01

Muscle work during level walking and ascent and descent ramp and stairway walking was assessed in order to explore the proposition that muscles perform more positive than negative work during these locomotion tasks. Thirty four healthy human adults were tested while maintaining a constant average walking velocity in the five gait conditions. Ground reaction force and sagittal plane kinematic data were obtained during the stance phases of these gaits and used in inverse dynamic analyses to calculate joint torques and powers at the hip, knee and ankle. Muscle work was derived as the area under the joint power vs time curves and was partitioned into positive, negative and net components. Dependent t-tests were used to compare positive and negative work in level walking and net joint work between ascent and descent gaits on the ramp and stairs (P<0.010). Total negative and positive work in level walking was -34 J and 50 J, respectively, with the difference in magnitude being statistically significant (P<0.001). Level walking was therefore performed with 16 J of net positive muscle work per step. The magnitude of the net work in ramp ascent was 25% greater than the magnitude of net work in ramp descent (89 vs -71 J m(-1), P<0.010). Similarly, the magnitude of the net work in stair ascent was 43% greater than the magnitude of net work in stair descent (107 vs -75 J step(-1), P<0.000). We identified three potential causes for the reduced negative vs positive work in these locomotion tasks: (1) the larger magnitude of the accelerations induced by the larger ground reaction forces in descending compared to ascending gaits elicited greater energy dissipation in non-muscular tissues, (2) the ground reaction force vector was directed closer to the joint centers in ramp and stair descent compared to ascent, which reduced the load on the muscular tissues and their energy dissipating response, and (3) despite the need to produce negative muscle work in descending gaits, both ramp and stair descent also had positive muscle work to propel the lower extremity upward and forward into the swing phase movement trajectory. We used these data to formulate two novel hypotheses about human locomotion. First, level walking requires muscles to generate a net positive amount of work per gait cycle to overcome energy losses by other tissues. Second, skeletal muscles generate more mechanical energy in gait tasks that raise the center of mass compared to the mechanical energy they dissipate in gait tasks that lower the center of mass, despite equivalent changes in total mechanical energy.

19. Historic American Buildings Survey, 1932 measured drawing from old ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

19. Historic American Buildings Survey, 1932 measured drawing from old Philadelphia Survey, photocopy courtesy of the Free Library of Philadelphia DETAILS: MAIN STAIRS. - Woodford, Philadelphia, Philadelphia County, PA

11. Historic American Buildings Survey George Eisenman, Photographer Summer 1967 ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

11. Historic American Buildings Survey George Eisenman, Photographer Summer 1967 STAIRS FROM K STREET ENTRANCE - Capital Traction Company Powerhouse, 3142 K Street Northwest, Washington, District of Columbia, DC

Heart valve surgery - discharge

MedlinePlus

... weeks, or when you can easily climb 2 flights of stairs or walk a half-mile (800 ... vomiting or diarrhea You become pregnant or are planning to become pregnant Alternative Names Aortic valve replacement - ...

Comparative biomechanical analysis of current microprocessor-controlled prosthetic knee joints.

PubMed

Bellmann, Malte; Schmalz, Thomas; Blumentritt, Siegmar

2010-04-01

To investigate and identify functional differences of 4 microprocessor-controlled prosthetic knee joints (C-Leg, Hybrid Knee [also called Energy Knee], Rheo Knee, Adaptive 2). Tested situations were walking on level ground, on stairs and ramps; additionally, the fall prevention potentials for each design were examined. The measuring technology used included an optoelectronic camera system combined with 2 forceplates as well as a mobile spiroergometric system. The study was conducted in a gait laboratory. Subjects with unilateral transfemoral amputations (N=9; mobility grade, 3-4; age, 22-49y) were tested. Participants were fitted and tested with 4 different microprocessor-controlled knee joints. Static prosthetic alignment, time distance parameters, kinematic and kinetic data and metabolic energy consumption. Compared with the Hybrid Knee and the Adaptive 2, the C-Leg offers clear advantages in the provision of adequate swing phase flexion resistances and terminal extension damping during level walking at various speeds, especially at higher walking speeds. The Rheo Knee provides sufficient terminal extension; however, swing phase flexion resistances seem to be too low. The values for metabolic energy consumption show only slight differences during level walking. The joint resistances generated for descending stairs and ramps relieve the contralateral side to varying degrees. When walking on stairs, safety-relevant technical differences between the investigated joint types can be observed. Designs with adequate internal resistances offer stability advantages when the foot is positioned on the step. Stumble recovery tests reveal that the different knee joint designs vary in their effectiveness in preventing the patient from falling. The patient benefits provided by the investigated electronic prosthetic knee joints differ considerably. The C-Leg appears to offer the amputee greater functional and safety-related advantages than the other tested knee joints. Reduced loading of the contralateral side has been demonstrated during ramp and stair descent. Metabolic energy consumption does not vary significantly between the tested knees. Hence, this parameter seems not to be a suitable criterion for assessing microprocessor-controlled knee components. Copyright 2010 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Reliability, Validity, and Minimal Detectable Change of Four-Step Stair Climb Power Test in Community-Dwelling Older Adults.

PubMed

Ni, Meng; Brown, Lorna G; Lawler, Danielle; Bean, Jonathan F

2017-07-01

Stair climb power is an important clinical measure of lower-extremity power. The stair climb power test (SCPT) was validated by requiring individuals to climb a full flight of stairs. A 4-step SCPT (4SCPT) would be more clinically feasible and easier to perform, yet its reliability and validity are unknown. To evaluate reliability, validity, and minimal detectable change of 4SCPT among community-dwelling older adults. This study is a cross-sectional analysis of baseline data from a clinical trial. Fifty older adults ≥65 years of age, at risk for mobility decline, consented to participate in this ancillary study. Test-retest reliability was derived from 2 measurements within each participant measured by a single assessor. Pearson correlation analyses among leg power measures (4SCPT, SCPT, single leg press power at 40% and 70% of the 1-repetition maximum [SLP40, SLP70]) were performed. Separate multivariate linear regressions were conducted evaluating the associations between each leg power measure and 2 mobility outcomes, the Short Physical Performance Battery (SPPB) and habitual gait speed (HGS). Minimal detectable change was based on a 90% confidence interval (MDC 90 ). The 4SCPT had excellent test-retest reliability (ICC(2,1) = 0.951), and strong correlation with SCPT, SLP40, and SLP70 ( r = 0.85-0.96). The 4SCPT explained a greater amount of variance in the SPPB (R 2 = 0.31) than other leg power measurements (R 2 = 0.23-0.25). The 4SCPT (R 2 = 0.41) and SCPT (R 2 = 0.42) described equivalent amounts of variance in HGS, and greater than that with SLP40 (R 2 = 0.28) and SLP70 (R 2 = 0.30). The MDC 90 for 4SCPT was 44.0 watts. This was a cross-sectional analysis within a small, nonrepresentative sample. Interrater reliability was not evaluated. The 4SCPT shows scientific promise as a valid and reliable leg power measurement among community-dwelling older adults. © 2017 American Physical Therapy Association

20. Historic American Buildings Survey, 1932 measured drawing from old ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

20. Historic American Buildings Survey, 1932 measured drawing from old Philadelphia Survey, photocopy courtesy of the Free Library of Philadelphia FURTHER DETAILS: MAIN STAIRS. - Woodford, Philadelphia, Philadelphia County, PA

Tendinitis (image)

MedlinePlus

... fibrous structure that joins muscle to bone. Tendinitis pain in the knee is located in the front of the knee. ... going up and down stairs or inclines. Tendinitis knee pain can happen in runners, skiers, and cyclists.

12. Historic American Buildings Survey E. W. Russell, Photographer, August ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

12. Historic American Buildings Survey E. W. Russell, Photographer, August 4, 1936 EAST SIDE STAIR HEAD (BALCONY FLOOR) - Government Street Presbyterian Church, Government & Jackson Streets, Mobile, Mobile County, AL

13. Historic American Buildings Survey E. W. Russell, Photographer, September ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

13. Historic American Buildings Survey E. W. Russell, Photographer, September 15, 1936 STAIR ON E. WALL OF BASEMENT - Government Street Presbyterian Church, Government & Jackson Streets, Mobile, Mobile County, AL

18. GENERAL VIEW, LOOKING NORTHEAST TO SOUTHWEST, SHOWING RELATIONSHIP TO ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

18. GENERAL VIEW, LOOKING NORTHEAST TO SOUTHWEST, SHOWING RELATIONSHIP TO OFFICE AREA TO STAIRS - Oakland Army Base, Transit Shed, East of Dunkirk Street & South of Burma Road, Oakland, Alameda County, CA

Congenital Heart Defects and Physical Activity

MedlinePlus

... walking, swimming, biking, jogging, rowing, cross-country skiing, hiking or stair climbing. Team or court sports such ... a person is, the greater the anticipated cardiovascular benefit. Guidelines for the general population suggest at least ...

2. PERSPECTIVE VIEW (NORTH) INTO ESPLANADE OF NORTHWEST DEMIBASTION SHOWING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. PERSPECTIVE VIEW (NORTH) INTO ESPLANADE OF NORTHWEST DEMI-BASTION SHOWING REVETMENTS, COUNTERFORTS, GLACIS AND STAIRS - Fort Washington, Fort, 13551 Fort Washington Road, Fort Washington Forest, Prince George's County, MD

3. PERSPECTIVE VIEW (SOUTH) INTO ESPLANADE OF NORTHWEST DEMIBASTION SHOWING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. PERSPECTIVE VIEW (SOUTH) INTO ESPLANADE OF NORTHWEST DEMI-BASTION SHOWING REVETMENTS, COUNTERFORTS, GLACIS AND STAIRS - Fort Washington, Fort, 13551 Fort Washington Road, Fort Washington Forest, Prince George's County, MD

14. PERSPECTIVE VIEW (NORTH) INTO ESPLANADE OF SOUTHWEST DEMIBASTION SHOWING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

14. PERSPECTIVE VIEW (NORTH) INTO ESPLANADE OF SOUTHWEST DEMI-BASTION SHOWING REVETMENTS, RESTORED DOORS, GLACIS AND STAIRS - Fort Washington, Fort, 13551 Fort Washington Road, Fort Washington Forest, Prince George's County, MD

Crutches and children - stairs

MedlinePlus

... Put the good foot on the step and push up. Push down hard on the crutches to help lift ... Updated by: C. Benjamin Ma, MD, Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic ...

40 CFR 745.82 - Applicability.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., such as the individual stair treads and risers of a single staircase, the renovator is required to test... occur in the owner's residence, no child under age 6 resides there, no pregnant woman resides there, the...

Give your heart a workout

MedlinePlus

... mph Hiking uphill Cross-country skiing Stair climbing Soccer Jogging Jumping rope Tennis (singles) Basketball Heavy yard ... us Disclaimers Copyright Privacy Accessibility Quality Guidelines Viewers & Players MedlinePlus Connect for EHRs For Developers U.S. National ...

Research the Gait Characteristics of Human Walking Based on a Robot Model and Experiment

NASA Astrophysics Data System (ADS)

He, H. J.; Zhang, D. N.; Yin, Z. W.; Shi, J. H.

2017-02-01

In order to research the gait characteristics of human walking in different walking ways, a robot model with a single degree of freedom is put up in this paper. The system control models of the robot are established through Matlab/Simulink toolbox. The gait characteristics of straight, uphill, turning, up the stairs, down the stairs up and down areanalyzed by the system control models. To verify the correctness of the theoretical analysis, an experiment was carried out. The comparison between theoretical results and experimental results shows that theoretical results are better agreement with the experimental ones. Analyze the reasons leading to amplitude error and phase error and give the improved methods. The robot model and experimental ways can provide foundation to further research the various gait characteristics of the exoskeleton robot.

7. View (looking west) of the second floor corridor in ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. View (looking west) of the second floor corridor in the south segment of building. The second floor was designed for residential rental rooms. The guardrail, balusters, newel posts, and handrail, as well as the two upper-level door openings with transoms, are original features. The doors, proper, are nonoriginal and probably were installed when the second floor was converted to office use. The pair of doors (one leaf is open and one is closed) is located at the intermediate stair landing. The original exterior doorway (without a door) is located at the bottom of the stair. The upper-level door without a transom is nonoriginal, as are the floor tile and wall paneling. At the time of documentation a suspended ceiling and duct were removed to ... - Stroud Building, 31-33 North Central Avenue, Phoenix, Maricopa County, AZ

Injuries associated with infant walkers.

PubMed

2001-09-01

In 1999, an estimated 8800 children younger than 15 months were treated in hospital emergency departments in the United States for injuries associated with infant walkers. Thirty-four infant walker-related deaths were reported from 1973 through 1998. The vast majority of injuries occur from falls down stairs, and head injuries are common. Walkers do not help a child learn to walk; indeed, they can delay normal motor and mental development. The use of warning labels, public education, adult supervision during walker use, and stair gates have all been demonstrated to be insufficient strategies to prevent injuries associated with infant walkers. To comply with the revised voluntary standard (ASTM F977-96), walkers manufactured after June 30, 1997, must be wider than a 36-in doorway or must have a braking mechanism designed to stop the walker if 1 or more wheels drop off the riding surface, such as at the top of a stairway. Because data indicate a considerable risk of major and minor injury and even death from the use of infant walkers, and because there is no clear benefit from their use, the American Academy of Pediatrics recommends a ban on the manufacture and sale of mobile infant walkers. If a parent insists on using a mobile infant walker, it is vital that they choose a walker that meets the performance standards of ASTM F977-96 to prevent falls down stairs. Stationary activity centers should be promoted as a safer alternative to mobile infant walkers.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abdullah, Abdul Halim; Nor, Mohd Asri Mohd; Saman, Alias Mohd

Aseptic loosening effects are critical issues in encouraging long term stability of cemented hip arthroplasty. Stress shielding is believed to be an important factor that contributes to the aseptic loosening problems. The numerous changes in the prosthesis stem design are intended to minimize the stress shielding and aseptic loosening problems and to improve the long term performance of the implants. In this study, the stress distribution in cemented hip arthroplasty is established using finite element method. The taper of the prosthesis is designed to be 3 deg. at anterior/posterior, 3 deg. at medial/lateral and 10 deg. from wide lateral tomore » narrow medial. Major muscle loads and contact forces are simulated for walking (toe-off phase) and stair climbing load cases. Effects of prosthesis stem tapers on the resulting stress distribution are investigated. Results show that compressive stress dominates in the medial plane while tensile stress in the lateral plane of the femur. The corresponding stress levels of intact femur for walking and stair-climbing load cases are 22 and 29 MPa, respectively. The magnitude of Tresca stress for the THA femur in stair-climbing load case remains higher in the region of 85 MPa while the walking load case induces around 40 MPa. The stress range in the straight and single taper stem prosthesis is lower than 260 MPa, while localized Tresca stress is in the order of the yield strength of Ti-6Al-4V alloy for double and triple taper stem design.« less

Stroke treatment academic industry roundtable: research priorities in the assessment of neurothrombectomy devices.

PubMed

Saver, Jeffrey L; Jovin, Tudor G; Smith, Wade S; Albers, Gregory W; Baron, Jean-Claude; Boltze, Johannes; Broderick, Joseph P; Davis, Lisa A; Demchuk, Andrew M; DeSena, Salvatore; Fiehler, Jens; Gorelick, Philip B; Hacke, Werner; Holt, Bill; Jahan, Reza; Jing, Hui; Khatri, Pooja; Kidwell, Chelsea S; Lees, Kennedy R; Lev, Michael H; Liebeskind, David S; Luby, Marie; Lyden, Patrick; Megerian, J Thomas; Mocco, J; Muir, Keith W; Rowley, Howard A; Ruedy, Richard M; Savitz, Sean I; Sipelis, Vitas J; Shimp, Samuel K; Wechsler, Lawrence R; Wintermark, Max; Wu, Ona; Yavagal, Dileep R; Yoo, Albert J

2013-12-01

The goal of the Stroke Treatment Academic Industry Roundtable (STAIR) meetings is to advance the development of stroke therapies. At STAIR VIII, consensus recommendations were developed for clinical trial strategies to demonstrate the benefit of endovascular reperfusion therapies for acute ischemic stroke. Prospects for success with forthcoming endovascular trials are robust, because new neurothrombectomy devices have superior reperfusion efficacy compared with earlier-generation interventions. Specific recommendations are provided for trial designs in 3 populations: (1) patients undergoing intravenous fibrinolysis, (2) early patients ineligible for or having failed intravenous fibrinolysis, and (3) wake-up and other late-presenting patients. Among intravenous fibrinolysis-eligible patients, key principles are that CT or MRI confirmation of target arterial occlusions should precede randomization; endovascular intervention should be pursued with the greatest rapidity possible; and combined intravenous and neurothrombectomy therapy is more promising than neurothrombectomy alone. Among patients ineligible for or having failed intravenous fibrinolysis, scientific equipoise was affirmed and the need to randomize all eligible patients emphasized. Vessel imaging to confirm occlusion is mandatory, and infarct core and penumbral imaging is desirable in later time windows. Additional STAIR VIII recommendations include approaches to test multiple devices in a single trial, utility weighting of disability end points, and adaptive designs to delineate time and tissue injury thresholds at which benefits from intervention no longer accrue. Endovascular research priorities in acute ischemic stroke are to perform trials testing new, highly effective neuro thrombectomy devices rapidly deployed in patients confirmed to have target vessel occlusions.

Dynamic simulation of knee-joint loading during gait using force-feedback control and surrogate contact modelling.

PubMed

Walter, Jonathan P; Pandy, Marcus G

2017-10-01

The aim of this study was to perform multi-body, muscle-driven, forward-dynamics simulations of human gait using a 6-degree-of-freedom (6-DOF) model of the knee in tandem with a surrogate model of articular contact and force control. A forward-dynamics simulation incorporating position, velocity and contact force-feedback control (FFC) was used to track full-body motion capture data recorded for multiple trials of level walking and stair descent performed by two individuals with instrumented knee implants. Tibiofemoral contact force errors for FFC were compared against those obtained from a standard computed muscle control algorithm (CMC) with a 6-DOF knee contact model (CMC6); CMC with a 1-DOF translating hinge-knee model (CMC1); and static optimization with a 1-DOF translating hinge-knee model (SO). Tibiofemoral joint loads predicted by FFC and CMC6 were comparable for level walking, however FFC produced more accurate results for stair descent. SO yielded reasonable predictions of joint contact loading for level walking but significant differences between model and experiment were observed for stair descent. CMC1 produced the least accurate predictions of tibiofemoral contact loads for both tasks. Our findings suggest that reliable estimates of knee-joint loading may be obtained by incorporating position, velocity and force-feedback control with a multi-DOF model of joint contact in a forward-dynamics simulation of gait. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.

Subject-specific modeling of muscle force and knee contact in total knee arthroplasty.

PubMed

Navacchia, Alessandro; Rullkoetter, Paul J; Schütz, Pascal; List, Renate B; Fitzpatrick, Clare K; Shelburne, Kevin B

2016-09-01

Understanding the mechanical loading environment and resulting joint mechanics for activities of daily living in total knee arthroplasty is essential to continuous improvement in implant design. Although survivorship of these devices is good, a substantial number of patients report dissatisfaction with the outcome of their procedure. Knowledge of in vivo kinematics and joint loading will enable improvement in preclinical assessment and refinement of implant geometry. The purpose of this investigation was to describe the mechanics of total knee arthroplasty during a variety of activities of daily living (gait, walking down stairs, and chair rise/sit). Estimates of muscle forces, tibial contact load, location, and pressure distribution was performed through a combination of mobile fluoroscopy data collection, musculoskeletal modeling, and finite element simulation. For the activities evaluated, joint compressive load was greatest during walking down stairs; however, the highest contact pressure occurred during chair rise/sit. The joint contact moment in the frontal plane was mainly varus for gait and walking down stairs, while it was valgus during chair rise/sit. Excursion of the center of pressure on the tibial component was similar during each activity and between the medial and lateral sides. The main determinants of center of pressure location were internal-external rotation, joint load, and tibial insert conformity. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1576-1587, 2016. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Biomechanical analysis of a novel hemipelvic endoprosthesis during ascending and descending stairs.

PubMed

Liu, Dongxu; Hua, Zikai; Yan, Xinyi; Jin, Zhongmin

2016-10-01

In this study, the biomechanical characteristic of a newly developed adjustable hemipelvic prosthesis under dynamic loading conditions was investigated using explicit finite element method. Both intact and reconstructed pelvis models, including pelvis, femur and soft tissues, were established referring to human anatomic data using a solid geometry of a human pelvic bone. Hip contact forces during ascending stairs and descending stairs were imposed on pelvic models. Results showed that maximum von Mises stresses in reconstructed pelvis were 421.85 MPa for prostheses and 109.12 MPa for cortical bone, which were still within a low and elastic range below the yielding strength of Ti-6Al-4V and cortical bone, respectively. Besides, no significant difference of load transferring paths along pelvic rings was observed between the reconstructed pelvis and natural pelvis models. And good agreement was found between the overall distribution of maximum principal stresses in trabecular bones of reconstructed pelvis and natural pelvis, while at limited stances, principal stresses in trabecular bone of reconstructed pelvis were slightly lower than natural pelvis. The results indicated that the load transferring function of pelvis could be restored by this adjustable hemipelvic prosthesis. Moreover, the prosthesis was predicted to have a reliable short- and long-term performance. However, due to the occurrence of slightly lower principal stresses at a few stances, a porous structure applied on the interface between the prosthesis and bone would be studied in future work to obtain better long-term stability. © IMechE 2016.

Electromyographic preactivation pattern of the gluteus medius during weight-bearing functional tasks in women with and without anterior knee pain.

PubMed

Nakagawa, Theresa H; Muniz, Thiago B; Baldon, Rodrigo M; Maciel, Carlos D; Amorim, César F; Serrão, Fábio V

2011-01-01

Proximal factors have been proposed to influence the biomechanics of the patellofemoral joint. A delayed or diminished gluteus medius (GM) activation, before the foot contact on the ground during functional activities could lead to excessive femur adduction and internal rotation and be associated with anterior knee pain (AKP). There are few studies on this topic and the results were inconclusive, therefore, it is necessary to investigate the GM preactivation pattern during functional activities. To compare the GM electromyographic (EMG) preactivation pattern during walking, descending stairs and in single leg jump task in women with and without AKP. Nine women clinically diagnosed with AKP and ten control subjects with no history of knee injury participated in this study. We evaluated GM EMG linear envelope before the foot contact on the ground during walking and GM onset time and EMG linear envelope during descending stairs as well as in a single leg vertical jump. Mann-Whitney U tests were used to determine the between-group differences in GM EMG preactivation pattern. No between-group differences were observed in GM linear envelope during walking (P=0.41), GM onset time and linear envelope during descending stairs (P=0.17 and P=0.15) and single leg jump (P=0.81 and P=0.33). Women with AKP did not demonstrated altered GM preactivation pattern during functional weight bearing activities. Our results did not support the hypothesis that poor GM preactivation pattern could be associated with AKP.

[Circumscribed palmar hypokeratosis (CPM): The diagnostic value of dermoscopy].

PubMed

Topin-Ruiz, S; Debarre, J-M; Blanchard, E; Kettani, S; Valmier, P-J; Martin, L; Le Corre, Y

2017-03-01

Circumscribed palmar hypokeratosis (CPH) is a rare skin disease, first described in 2002, associated with sudden localized reduction of the corneal layer. In most cases, it presents as an isolated rounded erythematous palmar lesion on the thenar eminence. We describe the dermoscopic semiology of CPH in 3 cases. Three patients between the ages of 59 and 72 presented very limited erythematous lesions suggestive of CPH. Dermoscopic examination of these lesions provided similar findings. Biopsy, which was performed in one patient, confirmed the diagnosis of CPH. Two dermoscopic elements of CPH are characteristic: (1) the sides of the lesion have a "stair step" or "geological strata" type of configuration, and the thickness of the different strata varies; (2) the centre of the lesion showed a homogeneous erythematous area with a vascular pattern composed of dotted vessels of the superficial dermis and sometime vascular loops. These dermoscopic aspects are characteristic and enable CPH to be differentiated from Bowen's disease or porokeratosis of Mibelli. In Bowen's disease, there is no stair step like aspect to the sides of lesions; further, the centre of the lesion shows glomerular vessels (coiled vessels) and/or globular vessels (small red clods). In porokeratosis, peripheral keratotic "white track" structures comprise a single pigmented channel or a double white line. There is no "stair step" or central vascular pattern. The dermoscopic semiology of CPH is highly characteristic and enables differentiation from Bowen's disease and porokeratosis. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

The effects of Navy ship ladder descent on the knee internal joint reaction forces

NASA Astrophysics Data System (ADS)

Coulter, Jonathan D.; Weinhandl, Joshua T.; Bawab, Sebastian Y.; Ringleb, Stacie I.

2017-02-01

Military populations may be at risk for developing knee osteoarthritis and other knee problems when descending a Navy ship ladder, which differs from traditional stairs due to non-overlapping treads, a larger rise and a steeper inclination angle. The purpose of this study was to develop a forward dynamic model of the descent of a Navy ship ladder to determine how this motion affects the internal knee reaction forces and how altering the hamstring/quadriceps ratio affects the internal joint reaction forces in the knee. Kinematic and kinetic data were collected from three male sailors descending a replica of a Navy ship ladder and were used as input into a model constructed in OpenSim. The peak resultant joint reaction force was 6.6 × BW, which was greater than values reported in the literature in traditional stairs. Peak compressive and anterior joint reaction forces, 4.05 × BW and 5.46 × BW, respectively, were greater than reported values for a squat, a motion similar to descending a ship ladder. The average peak vertical and anterior internal joint reaction force at the knee were 4.05 × BW and 5.46 × BW, respectively. The resultant joint reaction forces calculated from the ladder descent were greater than stair descent and squatting. Little effects were found in the joint reaction forces after adjusting the quadriceps to hamstring muscle strength ratios, possibly because these ratios might change the distribution of the contact forces across the joint, not the resultant forces.

Effects of Prosthesis Stem Tapers on Stress Distribution of Cemented Hip Arthroplasty

NASA Astrophysics Data System (ADS)

Abdullah, Abdul Halim; Nor, Mohd Asri Mohd; Saman, Alias Mohd; Tamin, Mohd Nasir; Kadir, Mohammed Rafiq Abdul

2010-10-01

Aseptic loosening effects are critical issues in encouraging long term stability of cemented hip arthroplasty. Stress shielding is believed to be an important factor that contributes to the aseptic loosening problems. The numerous changes in the prosthesis stem design are intended to minimize the stress shielding and aseptic loosening problems and to improve the long term performance of the implants. In this study, the stress distribution in cemented hip arthroplasty is established using finite element method. The taper of the prosthesis is designed to be 3° at anterior/posterior, 3° at medial/lateral and 10° from wide lateral to narrow medial. Major muscle loads and contact forces are simulated for walking (toe-off phase) and stair climbing load cases. Effects of prosthesis stem tapers on the resulting stress distribution are investigated. Results show that compressive stress dominates in the medial plane while tensile stress in the lateral plane of the femur. The corresponding stress levels of intact femur for walking and stair-climbing load cases are 22 and 29 MPa, respectively. The magnitude of Tresca stress for the THA femur in stair-climbing load case remains higher in the region of 85 MPa while the walking load case induces around 40 MPa. The stress range in the straight and single taper stem prosthesis is lower than 260 MPa, while localized Tresca stress is in the order of the yield strength of Ti-6Al-4V alloy for double and triple taper stem design.

9. Historic American Buildings Survey Arthur C. Haskell, Photographer Apr. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

9. Historic American Buildings Survey Arthur C. Haskell, Photographer Apr. 1, 1939 (i) INT.- STAIR HALL, 1st. FLOOR, LOOKING NORTH - M.I.T., Rogers Building, 491 Boylston Street, Boston, Suffolk County, MA

Genetics Home Reference: LAMA2-related muscular dystrophy

MedlinePlus

... weakness of the facial muscles and tongue, but intelligence is usually normal. Heart problems and seizures occasionally ... walk and climb stairs, and life expectancy and intelligence are usually not affected in late-onset LAMA2 - ...

3. Historic American Buildings Survey Alex Bush, Photographer, September 11, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. Historic American Buildings Survey Alex Bush, Photographer, September 11, 1935 HALL AND STAIRS, EAST SIDE OF HALL, SHOWING REAR DOOR - Thomas W. White House, 461 Eustis Avenue, Huntsville, Madison County, AL

50. Historic American Buildings Survey, Donald W. Dickensheets, Photographer. March ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

50. Historic American Buildings Survey, Donald W. Dickensheets, Photographer. March 27, 1940. BURNT BRICK, UNPLASTERED. COFFERED CEILING. STAIR LANDING TO WEST TOWER. - San Xavier del Bac Mission, Mission Road, Tucson, Pima County, AZ

6. Historic American Buildings Survey James Rainey, Photographer May 7, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. Historic American Buildings Survey James Rainey, Photographer May 7, 1936 STAIRS FROM ROOM OF SECRETARY OF STATE SECOND FLOOR (Looking North) - Old State House, Main Street & Central Row, Hartford, Hartford County, CT

Exercise and age

MedlinePlus

... down the stairs STRETCHING Stretching can help your body stay flexible. To stay limber: Learn shoulder, upper arm, and calf stretches Take yoga classes Do everyday activities, such as making your bed or bending over to tie your shoes

29 CFR 1926.851 - Stairs, passageways, and ladders.

Code of Federal Regulations, 2010 CFR

2010-07-01

... building, when a stairwell is being used, it shall be properly illuminated by either natural or artificial... the structure of a building, shall be used. Other access ways shall be entirely closed at all times...

48. Second floor, looking southwest (possibly former multipurpose room) with ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

48. Second floor, looking southwest (possibly former multi-purpose room) with fire stair in center - Sheffield Farms Milk Plant, 1075 Webster Avenue (southwest corner of 166th Street), Bronx, Bronx County, NY

Tandem mobile robot system

DOEpatents

Buttz, James H.; Shirey, David L.; Hayward, David R.

2003-01-01

A robotic vehicle system for terrain navigation mobility provides a way to climb stairs, cross crevices, and navigate across difficult terrain by coupling two or more mobile robots with a coupling device and controlling the robots cooperatively in tandem.

13. Historic American Buildings Survey Alex Bush, Photographer, August 30, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

13. Historic American Buildings Survey Alex Bush, Photographer, August 30, 1936 SOUTH END OF BACK PORCH SHOWING BLINDS AND STAIR RAIL, SECOND FLOOR - Burford House, County Road 33 vicinity, Camden, Wilcox County, AL

31. Fourth floor, looking south at former milkstorage tank room, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

31. Fourth floor, looking south at former milk-storage tank room, spiral stair in right hand corner - Sheffield Farms Milk Plant, 1075 Webster Avenue (southwest corner of 166th Street), Bronx, Bronx County, NY

21. Historic American Buildings Survey, W. Jeter Eason Deputy District ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

21. Historic American Buildings Survey, W. Jeter Eason- Deputy District Officer, Photographer November 21, 1936 DETAIL OF DECORATIVE STAIR RISERS. - The Hermitage, U.S. Highway 70 North (4580 Rachel's Lane), Nashville, Davidson County, TN

71. FIRST FLOOR, ROOM 101, ENTRANCE HALL (SIDE WITH FIRE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

71. FIRST FLOOR, ROOM 101, ENTRANCE HALL (SIDE WITH FIRE DETECTOR), ARCHWAY TO STAIR HALL 100, LOOKING UP, DETAIL OF ARCHWAY SOFFIT. - Octagon House, 1799 (1741) New York Avenue, Northwest, Washington, District of Columbia, DC

53. VIEW OF CRUSHED OXIDIZED ORE BIN FROM EAST. SHOWS ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

53. VIEW OF CRUSHED OXIDIZED ORE BIN FROM EAST. SHOWS ACCESS STAIR TO FEED LEVEL; DUST COLLECTOR ON LEFT. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

30. Historic American Buildings Survey E. W. Russell, Photographer, May ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

30. Historic American Buildings Survey E. W. Russell, Photographer, May 8, 1936 STAIR IN HALL TOWARDS REAR, W. EXTENSION, 1st FLOOR - Spring Hill College, Main Building, Old Shell Road, Spring Hill, Mobile County, AL

7. Historic American Buildings Survey Alex Bush, Photographer, April 8, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. Historic American Buildings Survey Alex Bush, Photographer, April 8, 1935 RIGHT STAIRS TOWARDS WEST IN EAST END OF HALL EAST OF MAIN HALLWAY - Old Southern University, University Avenue (College Street), Greensboro, Hale County, AL

Six weeks of Mat Pilates training are enough to improve functional capacity in elderly women.

PubMed

Bertoli, Josefina; Biduski, Grazieli Maria; de la Rocha Freitas, Cíntia

2017-10-01

The aim of the study was to evaluate the effect of Mat Pilates on the functional capacity (FC) of elderly women before and after six weeks of intervention. Eighteen women aged 62.28 (±2.34) participated in the study. Timed Up and Go test, Timed Up Stairs, Timed Down Stairs, 30-s Chair Stand, Chair Sit-and-Reach and Back Scratch tests were assessed. The results showed significant improvements in all FC tests after six weeks of the Mat Pilates intervention. Summarizing, only six weeks of Mat Pilates training of 60 min per session, three times a week, three series beginning with six repetitions and eight repetitions at the last two weeks of intervention, were enough to improve FC in elderly women. Furthermore, the exercises difficulty increased from beginners to intermediate. Copyright © 2016 Elsevier Ltd. All rights reserved.

Changes in co-contraction during stair descent after manual therapy protocol in knee osteoarthritis: A pilot, single-blind, randomized study.

PubMed

Cruz-Montecinos, Carlos; Flores-Cartes, Rodrigo; Montt-Rodriguez, Agustín; Pozo, Esteban; Besoaín-Saldaña, Alvaro; Horment-Lara, Giselle

2016-10-01

Manual therapy has shown clinical results in patients with knee osteoarthritis. However, the biomechanical aspects during functional tasks have not been explored in depth. Through surface electromyography, the medial and lateral co-contractions of the knee were measured while descending stairs, prior and posterior to applying a manual therapy protocol in the knee, with emphasis on techniques of joint mobilization and soft-tissue management. Sixteen females with slight or moderate knee osteoarthritis were recruited (eight experimental, eight control). It was observed that the lateral co-contraction index of the experimental group, posterior to intervention, increased by 11.7% (p = 0.014). The application of a manual therapy protocol with emphasis on techniques of joint mobilization and soft-tissue management modified lateral co-contraction, which would have a protective effect on the joint. Copyright © 2016 Elsevier Ltd. All rights reserved.

Plastic dynamics of the Al0.5CoCrCuFeNi high entropy alloy at cryogenic temperatures: Jerky flow, stair-like fluctuation, scaling behavior, and non-chaotic state

NASA Astrophysics Data System (ADS)

Guo, Xiaoxiang; Xie, Xie; Ren, Jingli; Laktionova, Marina; Tabachnikova, Elena; Yu, Liping; Cheung, Wing-Sum; Dahmen, Karin A.; Liaw, Peter K.

2017-12-01

This study investigates the plastic behavior of the Al0.5CoCrCuFeNi high-entropy alloy at cryogenic temperatures. The samples are uniaxially compressed at 4.2 K, 7.5 K, and 9 K. A jerky evolution of stress and stair-like fluctuation of strain are observed during plastic deformation. A scaling relationship is detected between the released elastic energy and strain-jump sizes. Furthermore, the dynamical evolution of serrations is characterized by the largest Lyapunov exponent. The largest Lyapunov exponents of the serrations at the three temperatures are all negative, which indicates that the dynamical regime is non-chaotic. This trend reflects an ordered slip process, and this ordered slip process exhibits a more disordered slip process, as the temperature decreases from 9 K to 4.2 K or 7.5 K.

Stair-Step Particle Flux Spectra on the Lunar Surface: Evidence for Nonmonotonic Potentials?

NASA Technical Reports Server (NTRS)

Collier, Michael R.; Newheart, Anastasia; Poppe, Andrew R.; Hills, H. Kent; Farrell, William M.

2016-01-01

We present examples of unusual "stair-step" differential flux spectra observed by the Apollo 14 Suprathermal Ion Detector Experiment on the lunar dayside surface in Earth's magnetotail. These spectra exhibit a relatively constant differential flux below some cutoff energy and then drop off precipitously, by about an order of magnitude or more, at higher energies. We propose that these spectra result from photoions accelerated on the lunar dayside by nonmonotonic potentials (i.e.,potentials that do not decay to zero monotonically) and present a model for the expected differential flux. The energy of the cutoff and the magnitude of the differential flux are related to the properties of the local space environment and are consistent with the observed flux spectra. If this interpretation is correct, these surface-based ion observations provide a unique perspective that both complements and enhances the conclusions obtained by remote-sensing orbiter observations on the Moon's exospheric and electrostatic properties.

Powered AFO for Achilles tendon rupture.

PubMed

Yoshizawa, Nobuyuki

2008-01-01

This paper proposes a powered ankle foot orthosis (AFO) for the treatment of a ruptured Achilles tendon. Usually, conservative orthosis treatment requires about two months, and a motionless ankle degrades activities of daily living (ADL). It is difficult to go to school or work on foot, and a pair of crutches is needed to go up and down stairs. In order to improve the ADL, an electric powered AFO has been designed to improve the ability to walk with a fixed ankle joint. The sole of the proposed AFO is equipped with an electric actuator. The prototype actuator consists of Nd magnets and electromagnets and is lightweight and battery driven. The actuator can switch the upright posture and the stepped forward posture of the patient. In an experiment, the use of this electric AFO made it possible to walk and to ascend and descend stairs with a fixed ankle joint.

Are Physical Activity and Nutrition Indicators of the Checklist of Health Promotion Environments at Worksites (CHEW) Associated with Employee Obesity among Hotel Workers?

PubMed Central

Nigg, Claudio R.; Albright, Cheryl; Williams, Rebecca; Nichols, Carol; Renda, Gloria; Stevens, Victor J.; Vogt, Thomas M.

2010-01-01

Objective Worksites provide opportunities to reach more than 60% of adults in the United States, including populations diverse in race, ethnicity, gender, age, occupation, income, and health status. Employers that provide worksite weight management interventions have the potential to reduce sick leave, healthcare costs, and workers compensation costs, and increase employee morale and worker efficiency. Hotels specifically, represent a broad cross-section of job categories, and most hotels are staffed and operated similarly around the world. However, from our literature review, there have been no investigations of the association between the hotel environment and employees’ obesity. Methods For this study, we tested the relationship between environmental factors in hotels and employees’ body mass index (BMI). Results Overall no substantial correlations were found on any environmental variable. However, hotel size affected some relationships. Higher BMI was related to greater number of stairs, stair facilitation, and the healthy eating facilitation variables (excluding nutrition signs or posters) in medium sized hotels. Lower BMI was found with greater stair facilitation in small hotels; and with greater number of PA signs, lunchroom nutrition signs, and hotel nutrition signsin large hotels. Unionized status affected only two environmental variables. For unionized hotels, BMI was negatively correlated with PA signs and positively correlated with the healthy eating facilitation. Conclusions No logical pattern of association was found between workplace environmental factors and hotel employee BMI levels. Further research should investigate the interaction of the size and structure of the workplace with the impact of environmental efforts to reduce overweight and obesity. PMID:20061886

EFFECTS OF STRENGTH TRAINING ON PHYSICAL FUNCTION: INFLUENCE OF POWER, STRENGTH, AND BODY COMPOSITION

PubMed Central

Hanson, Erik D.; Srivatsan, Sindhu R.; Agrawal, Siddhartha; Menon, Kalapurakkal S.; Delmonico, Matthew J.; Wang, Min Q.; Hurley, Ben F.

2010-01-01

The purpose of this study was to determine (a) the effects of strength training (ST) on physical function and (b) the influence of strength, power, muscle volume (MV), and body composition on physical function. Healthy, inactive adults (n = 50) aged 65 years and older underwent strength, power, total body composition (% fat and fat free mass [FFM]), and physical function testing before and after 22 weeks of ST. Physical function testing consisted of tasks designed to mimic common physical activities of daily living (ADL). To improve internal validity of the assessment of mid-thigh intermuscular fat, subcutaneous fat, and knee extensors MV, a 10-week unilateral ST program using the untrained leg as an internal control preceded 12 weeks of whole-body ST. Strength, power, and FFM increased significantly with ST (all p < 0.05), whereas rapid walk, 5 chair stands, and get up and go time decreased significantly with ST in the overall group (all p < 0.05). Women improved significantly in both walking test times (both p < 0.05) but not in the stair climb test, whereas men improved in the stair climb test (p < 0.05) but not in walking test times. Multiple regression analysis revealed the highest R2 (0.28) for the change in chair stands time, followed by stair climb and usual walk at 0.27 and 0.21, respectively. ST improves performance in functional tasks important for ADLs. Changes in strength, power, and FFM are predictors of ST-induced improvements in these tasks. PMID:19910811

Wide step width reduces knee abduction moment of obese adults during stair negotiation.

PubMed

Yocum, Derek; Weinhandl, Joshua T; Fairbrother, Jeffrey T; Zhang, Songning

2018-05-15

An increased likelihood of developing obesity-related knee osteoarthritis may be associated with increased peak internal knee abduction moments (KAbM). Increases in step width (SW) may act to reduce this moment. The purpose of this study was to determine the effects of increased SW on knee biomechanics during stair negotiation of healthy-weight and obese participants. Participants (24: 10 obese and 14 healthy-weight) used stairs and walked over level ground while walking at their preferred speed in two different SW conditions - preferred and wide (200% preferred). A 2 × 2 (group × condition) mixed model analysis of variance was performed to analyze differences between groups and conditions (p < 0.05). Increased SW increased the loading-response peak knee extension moment during descent and level gait, decreased loading-response KAbMs, knee extension and abduction range of motion (ROM) during ascent, and knee adduction ROM during descent. Increased SW increased loading-response peak mediolateral ground reaction force (GRF), increased peak knee abduction angle during ascent, and decreased peak knee adduction angle during descent and level gait. Obese participants experienced disproportionate changes in loading-response mediolateral GRF, KAbM and peak adduction angle during level walking, and peak knee abduction angle and ROM during ascent. Increased SW successfully decreased loading-response peak KAbM. Implications of this finding are that increased SW may decrease medial compartment knee joint loading, decreasing pain and reducing joint deterioration. Increased SW influenced obese and healthy-weight participants differently and should be investigated further. Copyright © 2018. Published by Elsevier Ltd.

Gait adaptations in patients with chronic posterior instability of the knee.

PubMed

Hooper, D M; Morrissey, M C; Crookenden, R; Ireland, J; Beacon, J P

2002-03-01

A retrospective analysis was performed to assess gait in individuals with a long history of posterior knee instability. Descriptive study. There are few studies in the literature concerning evaluation of the biomechanics of the knee in patients with knee posterior instability. Nine individuals with posterior knee instability and a matched control group of uninjured subjects were tested in regards to knee kinematics and kinetics while walking and ascending and descending stairs. The mean follow up time for the individuals with posterior instability was 11.1 years. Individual satisfaction with the knee was measured by having participants complete the Flandry (also known as Hughston Clinic) self-assessment questionnaire. It was found that patients with knee posterior instability who indicated a higher level of satisfaction on the Flandry score walked in a manner that demonstrated greater peak knee extensor torque during stance phase, while less satisfied patients with knee posterior instability demonstrated lower peak knee extensor torque. There was a significant correlation between the self-assessment score and the peak knee extensor torque during level walking (P=0.003). During stair ascent and descent, patients with posterior instability averaged lower knee extensor torque and power than the control subjects, but those differences were only statistically significant in power while descending stairs (P=0.048). Individuals with chronic knee posterior instability modify their gait, and the adaptation can be predicted based upon the individuals self-assessment of their knee using the Flandry questionnaire. These data suggest that gait retraining may be a valuable addition to the traditional muscle strengthening programs, which are commonly used during conservative management of knee posterior instability.

Character, Incidence, and Predictors of Knee Pain and Activity After Infrapatellar Intramedullary Nailing of an Isolated Tibia Fracture.

PubMed

Obremskey, William; Agel, Julie; Archer, Kristin; To, Philip; Tornetta, Paul

2016-03-01

To study the activity and incidence of knee pain after sustaining an isolated tibia fracture treated with an infrapatellar intramedullary nail at 1 year. Retrospective review of prospective cohort. Multicenter Academic and Community hospitals. Four hundred thirty-seven patients with an isolated tibia fracture completed a 12-month assessment on pain and self-reported activity. Infrapatellar intramedullary nail. Demographic information, comorbid conditions, injury characteristics, and surgical technique were recorded. Knee pain was defined on a 1-7 scale with 1 being "no pain" and 7 being a "very great deal of pain." Knee pain >4 was considered clinically significant. Patients reported if they were "able," "able with difficulty," or "unable" to perform the following activities: kneel, run, climb stairs, and walk prolonged. Variables were tested in multilevel multivariable regression analyses. In knee pain, 11% of patients reported a "good deal" to a "very great deal" of pain (>4), and 52% of patients reported "no" or "very little" pain at 12 months. In activity at 12 months, 26% and 29% of patients were unable to kneel or run, respectively, and 31% and 35% of patients, respectively, stated they were able with difficulty or unable to use stairs or walk. Clinically significant knee pain (>4/7) was present in 11% of patients 1 year after a tibia fracture. Of note, 31%-71% of patients had difficulty performing or were unable to perform routine daily activities of kneeling, running, and stair climbing, or walking prolonged distances. Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Altered spatiotemporal characteristics of gait in older adults with chronic low back pain.

PubMed

Hicks, Gregory E; Sions, J Megan; Coyle, Peter C; Pohlig, Ryan T

2017-06-01

Previous studies in older adults have identified that chronic low back pain (CLBP) is associated with slower gait speed. Given that slower gait speed is a predictor of greater morbidity and mortality among older adults, it is important to understand the underlying spatiotemporal characteristics of gait among older adults with CLBP. The purposes of this study were to determine (1) if there are differences in spatiotemporal parameters of gait between older adults with and without CLBP during self-selected and fast walking and (2) whether any of these gait characteristics are correlated with performance of a challenging walking task, e.g. stair negotiation. Spatiotemporal characteristics of gait were evaluated using a computerized walkway in 54 community-dwelling older adults with CLBP and 54 age- and sex-matched healthy controls. Older adults with CLBP walked slower than their pain-free peers during self-selected and fast walking. After controlling for body mass index and gait speed, step width was significantly greater in the CLBP group during the fast walking condition. Within the CLBP group, step width and double limb support time are significantly correlated with stair ascent/descent times. From a clinical perspective, these gait characteristics, which may be indicative of balance performance, may need to be addressed to improve overall gait speed, as well as stair-climbing performance. Future longitudinal studies confirming our findings are needed, as well as investigations focused on developing interventions to improve gait speed and decrease subsequent risk of mobility decline. Copyright © 2017 Elsevier B.V. All rights reserved.

Is lower peripheral information weighted differently as a function of step number during step climbing?

PubMed

Graci, Valentina; Rabuffetti, Marco; Frigo, Carlo; Ferrarin, Maurizio

2017-02-01

The importance of peripheral visual information during stair climbing and how peripheral visual information is weighted as a function of step number during step climbing is unclear. Previous authors postulated that the knowledge of predictable characteristics of the steps may decrease reliance on foveal vision and transfer the online visual guidance of stair climbing to peripheral vision. Hence the aim of this study was to investigate if and how the occlusion of the lower peripheral visual field influenced stair climbing and if peripheral visual information was weighted differently between steps. Ten young adult male participants ascended a 5-step staircase under 2 visual conditions: full vision (FV) and lower visual occlusion (LO). Kinematic data (100Hz) were collected. The effect of Vision and Step condition on vertical forefoot clearance was examined with a Repeated Measures 2-way ANOVA. Tukey's HSD test was used for post-hoc comparisons. A significant interaction Vision x Step and main effect of Step were found (p<=0.04): vertical forefoot clearance was greater in LO compared to FV condition only on the 1st and the 2nd steps (p<0.013) and on the last step compared to the other steps (p<0.01). These findings suggest that online peripheral visual information is more relevant when negotiating the first two steps, rather than the end of a staircase and that the steps subsequent the first few ones may require different information likely based on proprioception or working memory of the step height. Copyright © 2016 Elsevier B.V. All rights reserved.

Are physical activity and nutrition indicators of the checklist of health promotion environments at worksites (CHEW) associated with employee obesity among hotel workers?

PubMed

Nigg, Claudio R; Albright, Cheryl; Williams, Rebecca; Nichols, Carol; Renda, Gloria; Stevens, Victor J; Vogt, Thomas M

2010-01-01

Worksites provide opportunities to reach more than 60% of adults in the United States, including populations diverse in race, ethnicity, gender, age, occupation, income, and health status. Employers that provide worksite weight management interventions have the potential to reduce sick leave, health care costs, and workers compensation costs, and increase employee morale and worker efficiency. Hotels specifically, represent a broad cross-section of job categories, and most hotels are staffed and operated similarly around the world. However, from our literature review, there have been no investigations of the association between the hotel environment and employees' obesity. For this study, we tested the relationship between environmental factors in hotels and employees' body mass index (BMI). Overall no substantial correlations were found on any environmental variable. However, hotel size affected some relationships. Higher BMI was related to greater number of stairs, stair facilitation, and the healthy eating facilitation variables (excluding nutrition signs or posters) in medium sized hotels. Lower BMI was found with greater stair facilitation in small hotels; and with greater number of physical activity (PA) signs, lunch room nutrition signs, and hotel nutrition signs in large hotels. Unionized status affected only two environmental variables. For unionized hotels, BMI was negatively correlated with PA signs and positively correlated with the healthy eating facilitation. No logical pattern of association was found between workplace environmental factors and hotel employee BMI levels. Further research should investigate the interaction of the size and structure of the workplace with the impact of environmental efforts to reduce overweight and obesity.

Character, Incidence, and Predictors of Knee Pain and Activity after Infrapatellar Intramedullary Nailing of an Isolated Tibia Fracture

PubMed Central

Obremskey, William; Agel, Julie; Archer, Kristin; To, Philip; Tornetta, Paul

2015-01-01

Objective To study the activity and incidence of knee pain after sustaining a isolated tibia fracture treated with an infrapatellar intramedullary nail at one year. Design Retrospective review of prospective cohort Setting Multicenter Academic and Community hospitals Patients 437 patients with an isolated tibia fracture completed a 12 month assessment on pain and self-reported activity. Intervention Infrapatellar Intramedullary Nail Outcomes Demographic information co-morbid conditions, injury characteristics, and surgical technique were recorded. Knee pain was defined on a 1-7 scale with 1 being “no pain” and 7 being a “very great deal of pain.” Knee pain > 4 was considered clinically significant. Patients reported if they were “able”, “able with difficulty” or “unable” to perform the following activities: kneel, run, climb stairs, and walk prolonged. Variables were tested in multilevel multivariable regression analyses. Results Knee Pain: 11% percent of patients reported a “good deal” to a “very great deal” of pain (> 4). 52% of patients reported “no” or “very little” pain at 12 months. Activity at 12 months: 26% and 29% of patients were unable to kneel or run, respectively. 31% and 35% of patients respectively stated they were able with difficulty or unable to use stairs or walk. Conclusion Clinically significant knee pain (>4/7) was present in 11% of patients one year after a tibia fracture. 31%-71% of patients had difficulty performing or were unable to perform routine daily activities of kneeling, running, and stair climbing or walking prolonged distances. PMID:26496180

85. Mezzanine level looking southwest showing workman crouched on main ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

85. Mezzanine level looking southwest showing workman crouched on main anchorage beam; beginning of helical stair down-flight at left, up-flight at right. October 1984. - Statue of Liberty, Liberty Island, Manhattan, New York County, NY

12. Historic American Buildings Survey John O. Brostrup, Photographer May ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

12. Historic American Buildings Survey John O. Brostrup, Photographer May 6, 1937 2:15 P.M. VIEW OF STAIR, WEST CORNER OF ENTRANCE HALL. - Holly Hill, Southeast of Friendship off MD 631, Friendship, Anne Arundel County, MD

15. BUILDING 1: FOURTH FLOOR (West Section), TOP LEVEL OF ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

15. BUILDING 1: FOURTH FLOOR (West Section), TOP LEVEL OF TUBS, SOUTH AND WEST WALLS. OPEN METAL BREWER'S STAIR VISIBLE ALONG WEST WALL - Boston Beer Company, 225-249 West Second Street, South Boston, Suffolk County, MA

11. Historic American Buildings Survey E. W. Russell, Photographer, August ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

11. Historic American Buildings Survey E. W. Russell, Photographer, August 4, 1936 STAIR ON WEST SIDE, VIEW THROUGH DOOR ON W. END OF FRONT PORTICO - Government Street Presbyterian Church, Government & Jackson Streets, Mobile, Mobile County, AL

3. Historic American Buildings Survey W. N. Manning, Photographer, January ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. Historic American Buildings Survey W. N. Manning, Photographer, January 26, 1935 STAIRS IN HALL SHOWING OLD TIME GUN ON WALL, ALSO LIVING ROOM ACROSS HALL - Freeman-Caver-Christian House, Upper Friendship Road, Oxford, Calhoun County, AL

9. TROJAN MILL, EXTERIOR FROM NORTHWEST, c. 191828. WINTER SNOW ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

9. TROJAN MILL, EXTERIOR FROM NORTHWEST, c. 1918-28. WINTER SNOW SHOWS LINE OF CRUDE ORE BIN STAIR. CREDIT JW. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

16. 4th floor roof, view west, north side of setback ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

16. 4th floor roof, view west, north side of setback to left and delivery stair bulkhead to right - Sheffield Farms Milk Plant, 1075 Webster Avenue (southwest corner of 166th Street), Bronx, Bronx County, NY

33. Historic American Buildings Survey E. W. Russell, Photographer, May ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

33. Historic American Buildings Survey E. W. Russell, Photographer, May 7, 1936 VIEW OF STAIR FROM 2nd STORY HALL, W. END OF BUILDING - Spring Hill College, Main Building, Old Shell Road, Spring Hill, Mobile County, AL

34. Historic American Buildings Survey E. W. Russell, Photographer, May ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

34. Historic American Buildings Survey E. W. Russell, Photographer, May 8, 1936 VIEW OF STAIR FROM REAR (SOUTH) OF HALL, 2nd FLOOR - Spring Hill College, Main Building, Old Shell Road, Spring Hill, Mobile County, AL

INTERIOR VIEW OF LANAI AND LIVING ROOM, LOOKING TOWARD THE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

INTERIOR VIEW OF LANAI AND LIVING ROOM, LOOKING TOWARD THE ENTRY HALL. STAIRS UP TO THE DINING ROOM ON THE LEFT. VIEW FACING WEST. - Hickam Field, Officers' Housing Type L, 702 Julian Avenue, Honolulu, Honolulu County, HI

ESB Clinical Biomechanics Award 2008: Complete data of total knee replacement loading for level walking and stair climbing measured in vivo with a follow-up of 6-10 months.

PubMed

Heinlein, Bernd; Kutzner, Ines; Graichen, Friedmar; Bender, Alwina; Rohlmann, Antonius; Halder, Andreas M; Beier, Alexander; Bergmann, Georg

2009-05-01

Detailed information about the loading of the knee joint is required for various investigations in total knee replacement. Up to now, gait analysis plus analytical musculo-skeletal models were used to calculate the forces and moments acting in the knee joint. Currently, all experimental and numerical pre-clinical tests rely on these indirect measurements which have limitations. The validation of these methods requires in vivo data; therefore, the purpose of this study was to provide in vivo loading data of the knee joint. A custom-made telemetric tibial tray was used to measure the three forces and three moments acting in the implant. This prosthesis was implanted into two subjects and measurements were obtained for a follow-up of 6 and 10 months, respectively. Subjects performed level walking and going up and down stairs using a self-selected comfortable speed. The subjects' activities were captured simultaneously with the load data on a digital video tape. Customized software enabled the display of all information in one video sequence. The highest mean values of the peak load components from the two subjects were as follows: during level walking the forces were 276%BW (percent body weight) in axial direction, 21%BW (medio-lateral), and 29%BW (antero-posterior). The moments were 1.8%BW*m in the sagittal plane, 4.3%BW*m (frontal plane) and 1.0%BW*m (transversal plane). During stair climbing the axial force increased to 306%BW, while the shear forces changed only slightly. The sagittal plane moment increased to 2.4%BW*m, while the frontal and transversal plane moments decreased slightly. Stair descending produced the highest forces of 352%BW (axial), 35%BW (medio-lateral), and 36%BW (antero-posterior). The sagittal and frontal plane moments increased to 2.8%BW*m and 4.6%BW*m, respectively, while the transversal plane moment changed only slightly. Using the data obtained, mechanical simulators can be programmed according to realistic load profiles. Furthermore, musculo-skeletal models can be validated, which until now often lacked the ability to predict properly the non-sagittal load values, e.g. varus-valgus and internal-external moments.

Association between stairs in the home and instrumental activities of daily living among community-dwelling older adults.

PubMed

Tomioka, Kimiko; Kurumatani, Norio; Hosoi, Hiroshi

2018-06-04

There is insufficient evidence regarding the relationship of home environment with functional capacity among community-dwelling older people without disabilities. We conducted a population-based longitudinal cohort study and examined whether stairs in the home were associated with capability to perform instrumental activities of daily living (IADL) in community-dwelling high-functioning older adults. The target population was individuals aged 65 years or older living in two municipalities in Nara Prefecture in Japan. At the baseline survey, residents who were independent in IADL (n = 6722) were included as survey subjects. Subjects were divided into three groups according to their home type; one-storey residences, walk-up residences, or residences with an elevator. IADL was evaluated using the Tokyo Metropolitan Institute of Gerontology Index of Competence. Multiple logistic regression analyses stratified by gender were used to calculate the odds ratio (OR) and a 95% confidence interval (CI) for a decline in IADL, with one-storey residences as a reference. Age, studied area, marital status, working status, self-perceived economic status, body mass index, chronic diseases, smoking, drinking, eating habits, basic activities of daily living, cognitive functioning, depression, self-rated health, and social participation were used as covariates. During the 3-year follow-up, 11.6% of the subjects showed a decline in IADL. After adjusting for covariates, women who lived in walk-up residences had a lower risk for IADL decline (adjusted OR = 0.72, 95% CI = 0.52-0.99), while living in a home with an elevator was not associated with IADL decline (adjusted OR = 0.94, 95% CI = 0.49-1.77). In contrast, there was no association between home type and IADL decline in men (walk-up residences, adjusted OR = 0.90, 95% CI = 0.71-1.14; residences with an elevator, adjusted OR = 0.82, 95% CI = 0.39-1.72). The presence of stairs in the home was associated with prevention of IADL decline over a 3-year period in older women without disabilities. Although a barrier-free house is recommended for older people, our findings indicate that a home with stairs may maintain the capability to perform IADL among older adults without disabilities.

Is stair climb power a clinically relevant measure of leg power impairments in at-risk older adults?

PubMed

Bean, Jonathan F; Kiely, Dan K; LaRose, Sharon; Alian, Joda; Frontera, Walter R

2007-05-01

To test the clinical relevance of the stair climb power test (SCPT) as a measure of leg power impairments in mobility-limited older adults. Cross-sectional analysis of baseline data from participants within a randomized controlled trial. Rehabilitation research gym. Community-dwelling older adults (N=138; mean age, 75.4 y) with mobility limitations as defined by the Short Physical Performance Battery (SPPB). Not applicable. Leg power measures included the SCPT and double leg press power measured at 40% (DLP40) and 70% (DLP70) of the 1 repetition maximum. Mobility performance tests included the SPPB and its 3 components: gait speed, chair stand time, and standing balance. Stair climb power per kilogram (SCP/kg) had correlations of moderate strength (r=.47, r=.52) with DLP40/kg and DLP70/kg, respectively. All 3 leg power measures correlated with each of the mobility performance measures with the exception of DLP40/kg (r=.11, P=.27) and DLP70/kg (r=.11, P=.18) with standing balance. Magnitudes of association, as described by the Pearson correlation coefficient, did not differ substantively among the separate power measures as they related to SPPB performance overall. Separate adjusted multivariate models evaluating the relationship between leg power and SPPB performance were all statistically significant and described equivalent amounts of the total variance (R(2)) in SPPB performance (SCP/kg, R(2)=.30; DLP40, R(2)=.32; DLP70, R(2)=.31). Analyses of the components of the SPPB show that the SCPT had stronger associations than the other leg power impairment measures with models predicting chair stand (SCP/kg, R(2)=.25; DLP40, R(2)=.12; DLP70, R(2)=.13), whereas both types of leg press power testing had stronger associations with models predicting gait speed (SCP/kg, R(2)=.16; DLP40, R(2)=.34; DLP70, R(2)=.34). Stair climb power was the only power measure that was a significant component of models predicting standing balance (SCP/kg R(2)=.20). The SCPT is a clinically relevant measure of leg power impairments. It is associated with more complex modes of testing leg power impairments and is meaningfully associated with mobility performance, making it suitable for clinical settings in which impairment-mobility relationships are of interest.

Lower limb alactic anaerobic power output assessed with different techniques in morbid obesity.

PubMed

Lafortuna, C L; Fumagalli, E; Vangeli, V; Sartorio, A

2002-02-01

Short-term alactic anaerobic performance in jumping (5 consecutive jumps with maximal effort), sprint running (8 m) and stair climbing (modified Margaria test) were measured in 75 obese subjects (BMI: 40.3+/-5.0 kg/m2) and in 36 lean control subjects (BMI: 22.4+/-3.2 kg/m2) of the same age and gender distribution. The results show that obese subjects attained a significantly lower specific (per unit body mass) power output both in jumping (W(spec,j); p<0.001) and stair climbing (W(spec,s); p<0.001) and run at a significantly lower average velocity (v; p<0.001) during sprinting. In spite of the different motor skillfulness required to accomplish the jumping and climbing tests, W(spec,s) (and hence the vertical velocity in climbing, v(v)) was closely correlated with W(spec,j) (R2=0.427, p<0.001). In jumping, although the average force during the positive work phase was significantly higher in obese subjects (p<0.001), no difference between the 2 groups was detected in absolute power. In stair climbing the absolute power output of obese resulted significantly higher (18%) than that of lean controls (p<0.001). In sprint running, the lower average horizontal velocity attained by obese subjects also entailed a different locomotion pattern with shorter step length (L(s); p<0.001), lower frequency (p<0.001) and longer foot contact time with ground (T(c,r); p<0.001). W(spec,j) seems to be a determinant of the poorer motor performance of obese, being significantly correlated with: I) the vertical displacement of the centre of gravity (R2=0.853, p<0.001) in jumping; II) with v(v) in stair climbing; and III) with T(c,r) (R2=0.492, p<0.001), L(s) (R2=0.266, p<0.001) and v (R2=0.454, p<0.001) in sprinting. The results suggest that obese individuals, although partially hampered in kinetic movements, largely rely on their effective specific power output to perform complex anaerobic tasks, and they suffer from the disproportionate excess of inert mass of fat. Furthermore, in view of the sedentary style of life and the consequent degree of muscle de-conditioning accompanying this condition, it may prove useful to implement rehabilitation programs for obesity with effective power training protocols.

33. Oakland Port and General Depot. Transit Shed No. 7, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

33. Oakland Port and General Depot. Transit Shed No. 7, 936 feet, Building 127 STAIR & TOILET ROOM DETAILS. Sheet 6 of 16 - Oakland Army Base, Transit Shed, East of Dunkirk Street & South of Burma Road, Oakland, Alameda County, CA

31. Oakland Port and General Depot. Transit Shed No. 7, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

31. Oakland Port and General Depot. Transit Shed No. 7, 936 feet, Building 127 STAIR & TOILET ROOM DETAILS. Sheet 3 of 16 - Oakland Army Base, Transit Shed, East of Dunkirk Street & South of Burma Road, Oakland, Alameda County, CA

97. VIEW OF MILL SOLUTION PUMP No. 2 FROM SOUTHEAST. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

97. VIEW OF MILL SOLUTION PUMP No. 2 FROM SOUTHEAST. SUMPS ARE UNDER FLOOR, BEYOND. STAIR LEADS TO AGITATOR/GOLD TANK ACCESS PLATFORM. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

Photocopy of photograph (digital image located in LBNL Photo Lab ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Photocopy of photograph (digital image located in LBNL Photo Lab Collection, XBD200503-00117-108). March 2005. FAN ROOM WITH STAIR TO FILTER BANKS, BEVATRON - University of California Radiation Laboratory, Bevatron, 1 Cyclotron Road, Berkeley, Alameda County, CA

Sculpture, perspective view looking to pair of lions positioned at ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Sculpture, perspective view looking to pair of lions positioned at top of stairs leading down into the Glen - National Park Seminary, Bounded by Capitol Beltway (I-495), Linden Lane, Woodstove Avenue, & Smith Drive, Silver Spring, Montgomery County, MD

The Lighthouse Project.

ERIC Educational Resources Information Center

LeRose, Barbara; And Others

1979-01-01

The project is based on a general systems approach. Developmental stage theory is employed as a starting point, and the developmental "minitasks" which act as stair risers from one developmental level to another are carried through with the use of Bloom's cognitive taxonomy. (Author/DLS)

5. EXTERIOR OF NORTH SIDE SHOWING ENCLOSED FRONT PORCH AREA, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. EXTERIOR OF NORTH SIDE SHOWING ENCLOSED FRONT PORCH AREA, ALUMINUM SLIDING GLASS WINDOW GLAZING REPLACEMENTS, AND RAILING FOR STAIRS TO BASEMENT. VIEW TO SOUTHWEST. - Bishop Creek Hydroelectric System, Plant 4, Worker Cottage, Bishop Creek, Bishop, Inyo County, CA

5. WEST SIDE, FROM ACROSS 3RD STREET, LOOKING EAST, WITH ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. WEST SIDE, FROM ACROSS 3RD STREET, LOOKING EAST, WITH NAVY EXCHANGE RETAIL SERVICE AT TOP OF STAIRS. - Oakland Naval Supply Center, Administration Building-Cafeteria, East of Third Street between D & E Streets, Oakland, Alameda County, CA

34. Photographic copy of architects plan dated October 1919, (original ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

34. Photographic copy of architects plan dated October 1919, (original in possession of Montana State University, Bozeman, Montana.) REVISED PLAN AT 2nd FLOOR MAIN STAIRS - Hardin City Water Works, 101 East Fourth Street, Hardin, Big Horn County, MT

Dynamic Clinical Assessment of Femoral Acetabular Impingement

PubMed Central

Maak, Travis; Kraszewski, Andrew; Ranawat, Anil S.; Backus, Sherry I.; Magennis, Erin; Hillstrom, Howard; Kelly, Bryan T.

2013-01-01

Objectives: There has been a recent interest in the non-arthritic hip and its associated complex pathologies. Passive range of motion and static specialty tests are the corner stone of diagnosis and assessment of treatment. Little information exists on the use of dynamic functional measurements to assess non-arthritic hip function. The aims of this study were: (1) to measure and identify objective and reliable functional parameters to assess dynamic hip function, and (2) to compare functional kinematic and kinetic parameters among healthy controls and subjects with symptomatic diagnosed femoral acetabular impingement (FAI). Methods: An ongoing cross-sectional study was conducted on male healthy non-arthritic control and symptomatic, diagnosed FAI subjects. Functional kinematic and kinetic data were acquired with dynamic 3D motion analysis during stair ascent, stair descent, and a sit-to-stand maneuver. Joint kinematics were measured in degrees and joint kinetic moments were normalized by body mass (N-m/kg). Surface electromyographic (EMG) activity was measured for hip and trunk musculature. Measurement reliability was quantified with the adjusted coefficient of multiple correlation (CMC), and was calculated for angle, moment and EMG per subject, and averaged across subjects. Control and FAI subjects were compared with differences in kinematic and kinetic waveforms. Results: Data from ten healthy subjects (Age=25±4 years; BMI=24.3±3.6); and six FAI subjects (Age=32±10 years; BMI=25±4) have been recorded. Control and FAI subject CMC values are listed in Table 1. Kinematic and kinetic behavior differed (>1 SD) between control and FAI for multiple joints and planes of motion. Increased internal hip rotation moments were recorded in FAI subjects during both stair ascent and descent tasks, as compared to healthy controls. Increased external rotation moments were recorded in FAI subjects during the sit-to-stand task. Electromyographic data demonstrated notable differences (>1 SD) between healthy and FAI subjects (Figure 1). The stair ascent task elicited increased medial hamstring EMG activity, stair descent produced decreased gluteus medius EMG activity, and early sit-to-stand produced decreased rectus femoris EMG activity in FAI subjects, as compared to healthy controls. Conclusion: Overall the kinematic, kinetic and EMG repeatability was very reliable; these measures are sufficiently reliable to objectively assess dynamic function in healthy and pathologic subjects. Kinematic and kinetic data have shown striking differences between the kinematic and kinetic data of control and FAI subjects, particularly the increased external rotation moments and pelvic flexion during sit to stand for subjects with FAI. We hypothesize that increased pelvic flexion with FAI may be a reason why patients develop impingement and symptoms. Likewise, the decreased medial hamstring and rectus femoris activation in FAI subjects may be an attempt to decrease lumbar lordosis, which may be a compensatory behavior to decrease anterior impingement. In addition, we hypothesize that decreased gluteus medius EMG activity in FAI patients is a sign of abductor fatigue. This study provides a foundation to assess specific gait abnormalities associated with FAI, which will advance the understanding of this pathology and direct future treatment regimens.

1. Title Sheet; Door Profiles; Roof Truss, Protestant Chapel; Mess ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. Title Sheet; Door Profiles; Roof Truss, Protestant Chapel; Mess Hall/Corridor Window Jamb; Circular Stair Newel Post and Balustrade - National Home for Disabled Volunteer Soldiers - Battle Mountain Sanitarium, Mess Hall, 500 North Fifth Street, Hot Springs, Fall River County, SD

3. CABLE TUNNEL TO TEST STAND 1A, LOOKING SOUTH TO ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. CABLE TUNNEL TO TEST STAND 1-A, LOOKING SOUTH TO STAIRS LEADING UP TO CONTROL CENTER. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Control Center, Test Area 1-115, near Altair & Saturn Boulevards, Boron, Kern County, CA

Photocopy of drawing located at National Archives, San Bruno, California ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Photocopy of drawing located at National Archives, San Bruno, California (Navy # H-72-A-11). Stairs elevator hatch and solarium; N.D. - Mare Island Naval Shipyard, Hospital Wards, Cedar Avenue, eat side between Fourteenth Avenue & Cossey Street, Vallejo, Solano County, CA

Photographic copy of architectural drawing, 1921 (original located at University ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Photographic copy of architectural drawing, 1921 (original located at University of Minnesota Facilities Management Office, Minneapolis). DETAIL OF MAIN STAIR AND MISCELLANEOUS PLANS - Mines Experiment Station, University of Minnesota, Twin Cities Campus, 56 East River Road, Minneapolis, Hennepin County, MN

78 FR 35173 - Physical Medicine Devices; Reclassification of Stair-Climbing Wheelchairs

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-12

.... Electromagnetic interference: The device may interfere with the operation of other electrical devices or be... electromagnetic compatibility testing as well as characterization of speed/acceleration, battery longevity, and... electrical safety and electromagnetic compatibility of the device. Performance testing must demonstrate...

14. Bottom floor, tower interior showing base of stairway to ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

14. Bottom floor, tower interior showing base of stairway to lantern; details shown of iron castings for newel post, railing, and stair treads and risers. - Block Island Southeast Light, Spring Street & Mohegan Trail at Mohegan Bluffs, New Shoreham, Washington County, RI

Fourth floor, view looking from the reception cube (402A) to ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Fourth floor, view looking from the reception cube (402A) to elevator and stair (note radio controlled temperature and humidity device and the water fountain) - Virginia State Capitol, Bank and 10th Streets, Capitol Square, Richmond, Independent City, VA

Photocopy of drawing located at National Archives, San Bruno, California ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Photocopy of drawing located at National Archives, San Bruno, California (Navy # 505-A-11). Tower and stair details; October, 1938. - Mare Island Naval Shipyard, Defense Electronics Equipment Operating Center, I Street, terminus west of Cedar Avenue, Vallejo, Solano County, CA

38. Historic American Buildings Survey E. W. Russell, Photographer, May ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

38. Historic American Buildings Survey E. W. Russell, Photographer, May 7, 1936 N. W. SIDE OF ROTUNDA, 3rd FLOOR, SHOWING W. AND N. HALLS AND STAIR OPENING - Spring Hill College, Main Building, Old Shell Road, Spring Hill, Mobile County, AL

4. Historic American Buildings Survey, Nelson E. Baldwin, Photographer, Jan. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

4. Historic American Buildings Survey, Nelson E. Baldwin, Photographer, Jan. 16, 1937, View - Second to Third Floor Stairs Old Homeopathic Hospital, 123 North Pearl St., Albany, N.Y. - Old Homeopathic Hospital (Interiors), 123 North Pearl Street, Albany, Albany County, NY

Tibial rotation under combined in vivo loading after single- and double-bundle anterior cruciate ligament reconstruction.

PubMed

Tsarouhas, Alexander; Iosifidis, Michael; Spyropoulos, Giannis; Kotzamitelos, Dimitrios; Tsatalas, Themistoklis; Giakas, Giannis

2011-12-01

To evaluate in vivo the differences in tibial rotation between single- and double-bundle anterior cruciate ligament (ACL)-reconstructed knees under combined loading conditions. An 8-camera optoelectronic system and a force plate were used to collect kinematic and kinetic data from 14 patients with double-bundle ACL reconstruction, 14 patients with single-bundle reconstruction, 12 ACL-deficient subjects, and 12 healthy control individuals while performing 2 tasks. The first included walking, 60° pivoting, and stair ascending, and the second included stair descending, 60° pivoting, and walking. The 2 variables evaluated were the maximum range of internal-external tibial rotation and the maximum knee rotational moment. Tibial rotation angles were not significantly different across the 4 groups (P = .331 and P = .851, respectively) or when side-to-side differences were compared within groups (P = .216 and P = .371, respectively) for the ascending and descending maneuvers, nor were rotational moments among the 4 groups (P = .418 and P = .290, respectively). Similarly, for the descending maneuver, the rotational moments were not significantly different between sides (P = .192). However, for the ascending maneuver, rotational moments of the affected sides were significantly lower by 20.5% and 18.7% compared with their intact counterparts in the single-bundle (P = .015) and double-bundle (P = .05) groups, respectively. High-intensity activities combining stair ascending or descending with pivoting produce similar tibial rotation in single- and double-bundle ACL-reconstructed patients. During such maneuvers, the reconstructed knee may be subjected to significantly lower rotational loads compared with the intact knee. Level III, retrospective comparative study. Copyright © 2011 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Pelvic movement strategies and leg extension power in patients with end-stage medial compartment knee osteoarthritis: a cross-sectional study.

PubMed

Kierkegaard, Signe; Jørgensen, Peter Bo; Dalgas, Ulrik; Søballe, Kjeld; Mechlenburg, Inger

2015-09-01

During movement tasks, patients with medial compartment knee osteoarthritis use compensatory strategies to minimise the joint load of the affected leg. Movement strategies of the knees and trunk have been investigated, but less is known about movement strategies of the pelvis during advancing functional tasks, and how these strategies are associated with leg extension power. The aim of the study was to investigate pelvic movement strategies and leg extension power in patients with end-stage medial compartment knee osteoarthritis compared with controls. 57 patients (mean age 65.6 years) scheduled for medial uni-compartmental knee arthroplasty, and 29 age and gender matched controls were included in this cross-sectional study. Leg extension power was tested with the Nottingham Leg Extension Power-Rig. Pelvic range of motion was derived from an inertia-based measurement unit placed over the sacrum bone during walking, stair climbing and stepping. Patients had lower leg extension power than controls (20-39 %, P < 0.01) and used greater pelvic range of motion during stair and step ascending and descending (P ≤ 0.03, except for pelvic range of motion in the frontal plane during ascending, P > 0.06). Furthermore, an inverse association (coefficient: -0.03 to -0.04; R (2) = 13-22 %) between leg extension power and pelvic range of motion during stair and step descending was found in the patients. Compared to controls, patients with medial compartment knee osteoarthritis use greater pelvic movements during advanced functional performance tests, particularly when these involve descending tasks. Further studies should investigate if it is possible to alter these movement strategies by an intervention aimed at increasing strength and power for the patients.

Altered control strategy between leading and trailing leg increases knee adduction moment in the elderly while descending stairs.

PubMed

Karamanidis, Kiros; Arampatzis, Adamantios

2011-02-24

The aim of the study was to examine the external knee adduction moments in a group of older and younger adults while descending stairs and thus the possibility of an increased risk of knee osteoarthritis due to altered knee joint loading in the elderly. Twenty-seven older and 16 younger adults descended a purpose-built staircase. A motion capture system and a force plate were used to determine the subjects' 3D kinematics and ground reaction forces (GRF) during locomotion. Calculation of the leg kinematics and kinetics was done by means of a rigid, three-segment, 3D leg model. In the initial portion of the support phase, older adults showed a more medio-posterior GRF vector relative to the ankle joint, leading to lower ankle joint moments (P<0.05). At the knee, the older adults demonstrated a more medio-posterior directed GRF vector, increasing in knee flexion and adduction in the second part of the single support phase (P<0.05). Further, GRF magnitude was lower in the initial and higher in the mid-portions of the support phase for the elderly (P<0.05). The results show that older adults descend stairs by using the trailing leg before the initiation of the double support phase more compared to the younger ones. The consequence of this altered control strategy while stepping down is a more medially directed GRF vector increasing the magnitude of external knee adduction moment in the elderly. The observed changes between leading and trailing leg in the elderly may cause a redistribution of the mechanical load at the tibiofemoral joint, affecting the initiation and progression of knee osteoarthritis in the elderly. Copyright © 2010 Elsevier Ltd. All rights reserved.

On the relationship between tibia torsional deformation and regional muscle contractions in habitual human exercises in vivo.

PubMed

Yang, Peng-Fei; Kriechbaumer, Andreas; Albracht, Kirsten; Sanno, Maximilian; Ganse, Bergita; Koy, Timmo; Shang, Peng; Brüggemann, Gert-Peter; Müller, Lars Peter; Rittweger, Jörn

2015-02-05

The mechanical relationship between bone and muscle has been long recognized. However, it still remains unclear how muscles exactly load on bone. In this study, utilizing an optical segment tracking technique, the in vivo tibia loading regimes in terms of tibia segment deformation in humans were investigated during walking, forefoot and rear foot stair ascent and running and isometric plantar flexion. Results suggested that the proximal tibia primarily bends to the posterior aspect and twists to the external aspect with respect to the distal tibia. During walking, peak posterior bending and peak torsion occurred in the first half (22%) and second half (76%) of the stance phase, respectively. During stair ascent, two noticeable peaks of torsion were found with forefoot strike (38% and 82% of stance phase), but only one peak of torsion was found with rear foot strike (78% of stance phase). The torsional deformation angle during both stair ascent and running was larger with forefoot strike than rear foot strike. During isometric plantar flexion, the tibia deformation regimes were characterized more by torsion (maximum 1.35°) than bending (maximum 0.52°). To conclude, bending and torsion predominated the tibia loading regimes during the investigated activities. Tibia torsional deformation is closely related to calf muscle contractions, which further confirm the notion of the muscle-bone mechanical link and shift the focus from loading magnitude to loading regimes in bone mechanobiology. It thus is speculated that torsion is another, yet under-rated factor, besides the compression and tension, to drive long bone mechano-adaptation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Wear simulation of total knee prostheses using load and kinematics waveforms from stair climbing.

PubMed

Abdel-Jaber, Sami; Belvedere, Claudio; Leardini, Alberto; Affatato, Saverio

2015-11-05

Knee wear simulators are meant to perform load cycles on knee implants under physiological conditions, matching exactly, if possible, those experienced at the replaced joint during daily living activities. Unfortunately, only conditions of low demanding level walking, specified in ISO-14243, are used conventionally during such tests. A recent study has provided a consistent knee kinematic and load data-set measured during stair climbing in patients implanted with a specific modern total knee prosthesis design. In the present study, wear simulation tests were performed for the first time using this data-set on the same prosthesis design. It was hypothesised that more demanding tasks would result in wear rates that differ from those observed in retrievals. Four prostheses for total knee arthroplasty were tested using a displacement-controlled knee wear simulator for two million cycles at 1.1 Hz, under kinematics and load conditions typical of stair climbing. After simulation, the corresponding damage scars on the bearings were qualified and compared with equivalent explanted prostheses. An average mass loss of 20.2±1.5 mg was found. Scanning digital microscopy revealed similar features, though the explant had a greater variety of damage modes, including a high prevalence of adhesive wear damage and burnishing in the overall articulating surface. This study confirmed that the results from wear simulation machines are strongly affected by kinematics and loads applied during simulations. Based on the present results for the full understanding of the current clinical failure of knee implants, a more comprehensive series of conditions are necessary for equivalent simulations in vitro. Copyright © 2015 Elsevier Ltd. All rights reserved.

Arabic translation, cultural adaptation, and validation study of Knee Outcome Survey: Activities of Daily Living Scale (KOS-ADLS).

PubMed

Algarni, Abdulrahman D; Alrabai, Hamza M; Al-Ahaideb, Abdulaziz; Kachanathu, Shaji John; AlShammari, Sulaiman A

2017-09-01

Knee complaints and their accompanying functional impairments are frequent problems encountered by healthcare practitioners worldwide. Plenty of functional scoring systems were developed and validated to give a relative estimation about the knee function. Despite the wide geographic distribution of Arabic language in the Middle East and North Africa, it is rare to find a validated knee function scale in Arabic. The present study is aimed to translate, validate, and culturally adjust the Knee Outcome Survey: Activities of Daily Living Scale (KOS-ADLS) into Arabic language for future use among Arabic-speaking patients. Permission for translation was obtained from the copyrights holder. Two different teams of high-level clinical and linguistic expertise conducted translation process blindly. Forward-backward translation technique was implemented to ensure preservation of the main conceptual content. Main study consisted of 280 subjects. Reliability was examined by test-retest pilot study. Visual Analogue Scale (VAS), Get Up and Go (GUG) Test, Ascending/Descending Stairs (A/D Stairs), and Subjective Assessment of Function (SAF) were conducted concurrently to show the validity of Arabic KOS-ADLS statistically in relation to these scales. Final translated version showed no significant discrepancies. Minor adaptive adjustment was required to fit Arabian cultural background. Internal consistency was favourable (Cronbach's alpha 0.90). Patients' scoring on Arabic KOS-ADLS appeared relatively consistent with their scoring on VAS, GUG, A/D Stairs, and SAF. A significant linear relationship was demonstrated between SAF and total KOS-ADLS scores on regression analysis (adj. R 2  = 0.548). Arabic KOS-ADLS, as its English counterpart, was found to be a simple, valid, and useful instrument for knee function evaluation. Arabic version of KOS-ADLS represents a promising candidate for unconditional use among Arabic-speaking patients with knee complaints.

The role of the built environment and assistive devices for outdoor mobility in later life.

PubMed

Clarke, Philippa J

2014-11-01

Despite theoretical advances in our conceptualization of disability, the "environment" remains a largely unspecified term in disablement models. The purpose of this research is to draw upon on a unique state-of-the-art nationally representative data set with innovative measures that provide the opportunity to tease apart and specify the role of different environmental factors in the disablement process. Using multinomial logistic regression with data from the first round of the recently launched National Health and Aging Trends Study (N = 6,578 community-dwelling Americans age 65+), this paper examines the role of the built environment (e.g., stairs or ramps leading up to the home) and mobility devices on reported difficulty going outside by oneself. Almost three quarters of community-dwelling older Americans live in a residence that has stairs at the entrance. Older adults who use a walker to help them get around are adversely affected by stairs at the entrance to their home, effectively doubling the odds of reporting difficulty going outside independently. Roughly 10% of community-dwelling older Americans live in a residence with a ramp at the entryway, which reduces the odds of outdoor mobility difficulty threefold among those using wheeled mobility devices. However, ramps at the entryway are associated with a higher likelihood of reporting difficulty going outdoors among those who do not use any type of mobility device. A better understanding of the complexities of the environment in the disablement process is critical for the planning and development of age-friendly environments allowing older adults to age in place. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

An Intact Anterior Cruciate Ligament at the Time of Posterior Cruciate Ligament-Retaining Total Knee Arthroplasty Was Associated With Reduced Patient Satisfaction and Inferior Pain and Stair Function.

PubMed

Jacobs, Cale A; Christensen, Christian P; Karthikeyan, Tharun

2016-08-01

Patients with an intact anterior cruciate ligament (ACL) at the time of ACL-sacrificing total knee arthroplasty (TKA) have been suggested to have inferior outcomes compared with those with a dysfunctional ACL. However, to date, no published clinical studies have evaluated the potential link between the condition of the ACL at the time of posterior cruciate ligament-retaining TKA and postoperative pain, function, and satisfaction. As such, the purpose of this study was to compare subjective function, movement-elicited pain, pain at rest, and patient satisfaction between those with an intact or dysfunctional ACL. We identified 562 posterior cruciate ligament-retaining TKAs with complete intraoperative and postoperative data. Patients were categorized based on the condition of the ACL at the time of TKA as either being intact or dysfunctional (absent or lax). Knee Society Function Scores, movement-elicited pain, pain at rest, and patient satisfaction were then compared between groups. At mean follow-up of 5.1 years, a significantly lower proportion of patients in the intact group were satisfied with their operation (intact: 391/453 [86.3%] vs dysfunctional: 102/109 [93.6%], P = .0496). Inspection of the individual activities revealed that the groups did not differ in walking ability or pain when walking; however, the intact group reported significantly reduced ability to navigate stairs with greater pain during that activity. The lack of difference in pain at rest between groups suggests that pain and functional impairments during more demanding activities such as navigating stairs may be associated with the lost function of the ACL rather than by altered central pain processing. Copyright © 2016 Elsevier Inc. All rights reserved.

Sagittal plane joint kinetics during stair ascent in patients with peripheral arterial disease and intermittent claudication.

PubMed

King, Stephanie L; Vanicek, Natalie; O'Brien, Thomas D

2017-06-01

Stair negotiation poses a substantial physical demand on the musculoskeletal system and this challenging task can place individuals at risk of falls. Peripheral arterial disease (PAD) can cause intermittent claudication (IC) pain in the calf and results in altered gait mechanics during level walking. However, whether those with PAD-IC adopt alternate strategies to climb stairs is unknown. Twelve participants with PAD-IC (six bilateral and six unilateral) and 10 healthy controls were recruited and instructed to ascend a five-step staircase whilst 3D kinematic data of the lower-limbs were recorded synchronously with kinetic data from force plates embedded into the staircase on steps two and three. Limbs from the unilateral group and both limbs from the bilateral claudicants were categorised as claudicating (N=18), asymptomatic (N=6) and control (N=10). Claudicants walked more slowly than healthy controls (trend; P=<0.066). Both claudicating- and asymptomatic-limb groups had reduced propulsive GRF (P=0.025 and P=0.002, respectively) and vertical GRF (P=0.005 and P=0.001, respectively) compared to controls. The claudicating-limb group had a reduced knee extensor moment during forward continuance (P=0.060), ankle angular velocity at peak moment (P=0.039) and ankle power generation (P=0.055) compared to the controls. The slower gait speed, irrespective of laterality of symptoms, indicates functional capacity was determined by the limitations of the claudicating limb. Reduced ankle power generation and angular velocity (despite adequate plantarflexor moment) implies velocity-dependent limitations existed in the calf. The lack of notable compensatory strategies indicates reliance on an impaired muscle group to accomplish this potentially hazardous task, highlighting the importance of maintaining plantarflexor strength and power in those with PAD-IC. Copyright © 2017 Elsevier B.V. All rights reserved.

Functional, Sensorial, Mobility and Communication Difficulties in the Portuguese Oldest Old (80+).

PubMed

Brandão, Daniela; Ribeiro, Óscar; Paúl, Constança

2017-06-30

The ageing of populations is evident in most developed countries, and the oldest old group is one of the segments with the fastest growing. The aim of this paper is to examine sociodemographic and health related characteristics of the portuguese oldest old, using a census-based approach. A descriptive study considering all residents aged 80 years and older at the time of the 2011 Census (n = 532 219) was conducted. Information on sociodemographic characteristics, sensory functions (seeing, hearing), functional status (walking/climbing stairs, bathing/dressing alone), cognition (memory/concentration), and communication (understanding others/being understood) as assessed by the Portuguese census official questionnaires were analyzed. Findings revealed that most of the oldest old are women (64.5%), widowed (53.9%), illiterate (46.1%) and live in private households (88.8%). Walking/climbing stairs (57.1%), vision (39.1%) and hearing (35.1%) were the dimensions where the oldest old presented major constrains. In parallel, understanding others/being understood (25.9%) and memory/concentration (34.4%) were the dimensions with lower percentages of difficulties. Significant differences were found between octogenarians/nonagenarians and centenarians for vision, walk/climb stairs, and bathing/dressing alone, with centenarians presenting a higher percentage of difficulties. Portuguese oldest old showed significant difficulties in activities of daily living, nevertheless cognitive and communication capacities seem to be commonly maintained. Taken together, these findings suggest the need for functional assistance, which can be ultimately managed by the older person him/herself. Based on the observed differences between centenarians and younger oldest old, specific interventions should be equated to better respond to their potentially distinctive needs.

Influence of Lower Extremity Muscle Size and Quality on Stair-Climb Performance in Career Firefighters.

PubMed

Kleinberg, Craig R; Ryan, Eric D; Tweedell, Andrew J; Barnette, Timothy J; Wagoner, Chad W

2016-06-01

The purpose of this study was to examine the influence of lower extremity muscular size and quality on stair-climb performance (SCP) in career firefighters. Forty-six male career firefighters (age = 37.0 ± 7.2 years; stature = 180.2 ± 6.9 cm; body mass = 108.0 ± 19.8 kg) volunteered for this study. Panoramic ultrasound images of the vastus lateralis and rectus femoris were obtained to determine cross-sectional area (CSA) and echo intensity (EI) of each muscle. The CSA of each muscle was then summed together and normalized to body mass (CSA/BM [QCSA]). Additionally, EI was averaged across both muscles (QEI). Participants then performed a timed and weighted SCP assessment where they ascended and descended 26 stairs 4 times as quickly as possible while wearing a weighted vest (22.73 kg) to simulate the weight of their self-contained breathing apparatus and turnout gear. Bivariate correlations and stepwise regression analyses were used to examine the relationships among variables and the relative contributions of QCSA and QEI to SCP. Partial correlations were used to examine the relationship between QCSA and SCP and QEI and SCP while controlling for age and body mass index (BMI). The results indicated that QCSA and QEI were significantly related to SCP before (r = -0.492, p = 0.001; r = 0.363, p = 0.013, respectively) and after accounting for age and BMI (r = -0.324, p = 0.032; r = 0.413, p = 0.005, respectively). Both QCSA and QEI contributed significantly to the prediction of SCP (r = 0.560, p < 0.001). These findings indicate that lower extremity muscle size and quality are important contributors to critical firefighting tasks, which have been shown to be improved with resistance training.

8. VIEW OF ESCAPE TRAINING TANK, LOOKING NORTHEAST FROM 50FOOT ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

8. VIEW OF ESCAPE TRAINING TANK, LOOKING NORTHEAST FROM 50-FOOT PASSAGEWAY, SHOWING PORTION OF SPIRAL STAIR AND REPRESENTATIVE FLOOD LIGHT BLISTER - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT

Spleen removal - laparoscopic - adults - discharge

MedlinePlus

... own. Start walking soon after surgery. Begin your everyday activities as soon as you feel up to it. Move around the house, shower, and use the stairs at home during the first week. If it hurts when you do something, stop doing that activity. You may be ...

Improved Training Method for Rapid Rehabilitation of Amputees

DTIC Science & Technology

2013-03-01

crowded environments, stairs , ramps, and hills. The key factor that limits the ability of amputees to achieve maximum functional capabilities is falls...Method for evoking a trip response using a treadmill based perturbation during locomotion”, has been submitted to the Journal of Biomechanics o

Through the Front Door.

ERIC Educational Resources Information Center

Geller, Joseph

2002-01-01

Discusses challenges that arise in creating school entranceways that meld accessibility with attractiveness, noting the importance of considering both aesthetic impact and the design mandates of the Americans with Disabilities Act (ADA). Creative solutions include tying a walkway into a progressive stair; incorporating the ramp into a masonry…

25. DETAIL OF STRUCTURAL TIMBERS, ORE BIN, AND STAIRWAY TO ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

25. DETAIL OF STRUCTURAL TIMBERS, ORE BIN, AND STAIRWAY TO TOP FLOOR OF MILL, LOOKING SOUTH FROM SECOND FLOOR OF MILL. PORTION OF ORE BIN ON RIGHT, STAIRS ON LEFT. - Skidoo Mine, Park Route 38 (Skidoo Road), Death Valley Junction, Inyo County, CA

Exploring Slope with Stairs & Steps

ERIC Educational Resources Information Center

Smith, Toni M.; Seshaiyer, Padmanabhan; Peixoto, Nathalia; Suh, Jennifer M.; Bagshaw, Graham; Collins, Laurena K.

2013-01-01

As much as ever before, mathematics teachers are searching for ways to connect mathematics to real-life scenarios within STEM contexts. As students develop skill in proportional reasoning, they examine graphical representations of linear functions, learn to associate "slope" with "steepness" and rate of change, and develop…

Semantics and technologies in modern design of interior stairs

NASA Astrophysics Data System (ADS)

Kukhta, M.; Sokolov, A.; Pelevin, E.

2015-10-01

Use of metal in the design of interior stairs presents new features for shaping, and can be implemented using different technologies. The article discusses the features of design and production technologies of forged metal spiral staircase considering the image semantics based on the historical and cultural heritage. To achieve the objective was applied structural- semantic method (to identify the organization of structure and semantic features of the artistic image), engineering methods (to justify the construction of the object), anthropometry method and ergonomics (to provide usability), methods of comparative analysis (to reveale the features of the way the ladder in different periods of culture). According to the research results are as follows. Was revealed the semantics influence on the design of interior staircase that is based on the World Tree image. Also was suggested rational calculation of steps to ensure the required strength. And finally was presented technology, providing the realization of the artistic image. In the practical part of the work is presented version of forged staircase.

A theoretical study of special acoustic effects caused by the staircase of the El Castillo pyramid at the Maya ruins of Chichen-Itza in Mexico.

PubMed

Declercq, Nico F; Degrieck, Joris; Briers, Rudy; Leroy, Oswald

2004-12-01

It is known that a handclap in front of the stairs of the great pyramid of Chichen Itza produces a chirp echo which sounds more or less like the sound of a Quetzal bird. The present work describes precise diffraction simulations and attempts to answer the critical question what physical effects cause the formation of the chirp echo. Comparison is made with experimental results obtained from David Lubman. Numerical simulations show that the echo shows a strong dependence on the kind of incident sound. Simulations are performed for a (delta function like) pulse and also for a real handclap. The effect of reflections on the ground in front of the pyramid is also discussed. The present work also explains why an observer seated on the lowest step of the pyramid hears the sound of raindrops falling in a water filled bucket instead of footstep sounds when people, situated higher up the pyramid, climb the stairs.

A theoretical study of special acoustic effects caused by the staircase of the El Castillo pyramid at the Maya ruins of Chichen-Itza in Mexico

NASA Astrophysics Data System (ADS)

Declercq, Nico F.; Degrieck, Joris; Briers, Rudy; Leroy, Oswald

2004-12-01

It is known that a handclap in front of the stairs of the great pyramid of Chichen Itza produces a chirp echo which sounds more or less like the sound of a Quetzal bird. The present work describes precise diffraction simulations and attempts to answer the critical question what physical effects cause the formation of the chirp echo. Comparison is made with experimental results obtained from David Lubman. Numerical simulations show that the echo shows a strong dependence on the kind of incident sound. Simulations are performed for a (delta function like) pulse and also for a real handclap. The effect of reflections on the ground in front of the pyramid is also discussed. The present work also explains why an observer seated on the lowest step of the pyramid hears the sound of raindrops falling in a water filled bucket instead of footstep sounds when people, situated higher up the pyramid, climb the stairs. .

Autonomous stair-climbing with miniature jumping robots.

PubMed

Stoeter, Sascha A; Papanikolopoulos, Nikolaos

2005-04-01

The problem of vision-guided control of miniature mobile robots is investigated. Untethered mobile robots with small physical dimensions of around 10 cm or less do not permit powerful onboard computers because of size and power constraints. These challenges have, in the past, reduced the functionality of such devices to that of a complex remote control vehicle with fancy sensors. With the help of a computationally more powerful entity such as a larger companion robot, the control loop can be closed. Using the miniature robot's video transmission or that of an observer to localize it in the world, control commands can be computed and relayed to the inept robot. The result is a system that exhibits autonomous capabilities. The framework presented here solves the problem of climbing stairs with the miniature Scout robot. The robot's unique locomotion mode, the jump, is employed to hop one step at a time. Methods for externally tracking the Scout are developed. A large number of real-world experiments are conducted and the results discussed.

Does a Relationship Exist Between Lower Body Power and Balance Scores Among Older Adults?

PubMed

Shim, Andrew; Harr, Brady; Waller, Mike

2018-03-12

Falls are the second-leading cause of unintentional injury and death worldwide. To determine if a relationship exists between lower body power scores and center of pressure (CoP) and limits of stability (LoS) scores. A one-shot case study design (n = 13) was selected for the investigation. All participants were assessed stability scores via computerized posturography to determine CoP and LoS balance scores. Participants stood on a perturbed surface with their eyes open and closed. An experimental stair ramp with a switch mat timing device was used to determine lower body power scores in watts. There was a strong correlation (r = 0.725, p = 0.005) between the posterior (LoS) plane and relative peak power. An intraclass R revealed a strong correlation among the three trials (R = 0.831) performed on the stair ramp. Muscle power output and LoS scores have moderate to strong correlations with balance scores in older adults.

Effect of shoe type on descending a curb.

PubMed

George, Juff; Heller, Michelle; Kuzel, Michael

2012-01-01

The aim of this study was to evaluate the effect of shoe type on the performance of women during curb descent. Performance during curb stepping may be explained by biomechanical research that has evaluated the kinematics of overground walking and stair ascent and descent. Studies have reported that women exhibit performance differences when wearing high heels, flip flops and sneakers during overground walking and stair ascent and descent. Thus, in addition to features of the curb, the type of shoe being worn may also affect performance. Although several studies have investigated curb stepping, no known studies have investigated the effects of different types of footwear on curb descent performance. This research was conducted in a real-world environment where participants wore three different types of shoes and performed a series of activities that involved curb stepping. The subjects were videotaped while descending a curb, allowing for observation of changes in gait parameters. Results of this study indicate that wearing high heels leads to performance differences as compared to wearing flip flops or sneakers.

Multi-Sensor Fusion for Enhanced Contextual Awareness of Everyday Activities with Ubiquitous Devices

PubMed Central

Guiry, John J.; van de Ven, Pepijn; Nelson, John

2014-01-01

In this paper, the authors investigate the role that smart devices, including smartphones and smartwatches, can play in identifying activities of daily living. A feasibility study involving N = 10 participants was carried out to evaluate the devices' ability to differentiate between nine everyday activities. The activities examined include walking, running, cycling, standing, sitting, elevator ascents, elevator descents, stair ascents and stair descents. The authors also evaluated the ability of these devices to differentiate indoors from outdoors, with the aim of enhancing contextual awareness. Data from this study was used to train and test five well known machine learning algorithms: C4.5, CART, Naïve Bayes, Multi-Layer Perceptrons and finally Support Vector Machines. Both single and multi-sensor approaches were examined to better understand the role each sensor in the device can play in unobtrusive activity recognition. The authors found overall results to be promising, with some models correctly classifying up to 100% of all instances. PMID:24662406

[Positional asphyxia--death in a head-down position after falling down stairs].

PubMed

Doberentz, Elke; Madea, Burkhard

2012-01-01

The discovery of a body in an unusual position such as a head-down position requires thorough investigation. In this article, such a death is reported. A 64-year-old man was found in a head-down position at the bottom of a narrow staircase after obviously falling down the stairs. His head was wedged between the last step and a closed sliding door. Autopsy revealed craniofacial blunt force injuries, a non-dislocated fracture of the 4th cervical vertebral body (with intact ligaments of the spine and cervical cord) and massive cerebral and pulmonary oedema. Although the heart was significantly enlarged (610 g), the coronary arteries showed only minor arteriosclerotic changes. The alcohol concentration measured was 2.06 per mil in blood and 2.67 per mil in urine. The alcohol intoxication increased the risk to fall and together with the trauma of the cervical spine made it impossible for the man to free himself so that he ultimately died in a head-down position.

Multi-sensor fusion for enhanced contextual awareness of everyday activities with ubiquitous devices.

PubMed

Guiry, John J; van de Ven, Pepijn; Nelson, John

2014-03-21

In this paper, the authors investigate the role that smart devices, including smartphones and smartwatches, can play in identifying activities of daily living. A feasibility study involving N = 10 participants was carried out to evaluate the devices' ability to differentiate between nine everyday activities. The activities examined include walking, running, cycling, standing, sitting, elevator ascents, elevator descents, stair ascents and stair descents. The authors also evaluated the ability of these devices to differentiate indoors from outdoors, with the aim of enhancing contextual awareness. Data from this study was used to train and test five well known machine learning algorithms: C4.5, CART, Naïve Bayes, Multi-Layer Perceptrons and finally Support Vector Machines. Both single and multi-sensor approaches were examined to better understand the role each sensor in the device can play in unobtrusive activity recognition. The authors found overall results to be promising, with some models correctly classifying up to 100% of all instances.

11. A view on the roof, looking south, showing the ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

11. A view on the roof, looking south, showing the stair and elevator penthouses, air conditioning units and the coping as it follows the outline of the light wells. - John T. Beasley Building, 632 Cherry Street (between Sixth & Seventh Streets), Terre Haute, Vigo County, IN

Detail of one way mirror, mail slot, and electrical box ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Detail of one way mirror, mail slot, and electrical box at sentry post no. 3, top of east stairs near the end of second floor corridor - March Air Force Base, Strategic Air Command, Combat Operations Center, 5220 Riverside Drive, Moreno Valley, Riverside County, CA

Factor Analysis of Various Anaerobic Power Tests.

ERIC Educational Resources Information Center

Manning, James M.; And Others

A study investigated the relationship between selected anthropometric variables and of numerous anaerobic power tests with measures obtained on an isokinetic dynamometer. Thirty-one male college students performed several anaerobic power tests, including: the vertical jump using the Lewis formula; the Margaria-Kalamen stair climb test; the Wingate…

Interior view, secondfloor corridor looking east. Note the door to ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Interior view, second-floor corridor looking east. Note the door to Egyptian Hall in the center distance and the door to Gothic Hall on the eastern entresol (third floor) at the top of the stairs - Masonic Temple, 1 North Broad Street, Philadelphia, Philadelphia County, PA

32. PILOT HOUSE, LOOKING TOWARDS PORT, TABLE TO LEFT IS ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

32. PILOT HOUSE, LOOKING TOWARDS PORT, TABLE TO LEFT IS WHERE CHARTS ARE PLOTTED AT BACKGROUND LEFT IS TOP OF STAIRS DOWN TO MESS DECK. - U.S. Coast Guard Cutter WHITE HEATH, USGS Integrated Support Command Boston, 427 Commercial Street, Boston, Suffolk County, MA

DETAIL VIEW, SOUTH PORTICO. THE BARE GROUND BENEATH THE PORTICO’S ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

DETAIL VIEW, SOUTH PORTICO. THE BARE GROUND BENEATH THE PORTICO’S CENTER BAY DISCLOSES THE LOCATION OF A REMOVED STAIR. THE ORIGINAL FRAME STAIRCASES UP TO THE PORTICO EXTENDED FROM THE EAST AND WEST SIDES - The Woodlands, 4000 Woodlands Avenue, Philadelphia, Philadelphia County, PA

4. NORTH END OF TERMINAL ROOM, SHOP LEVEL SHOWING SPIRAL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

4. NORTH END OF TERMINAL ROOM, SHOP LEVEL SHOWING SPIRAL STAIR TO CABLE RACK. Looking north. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A Terminal Room, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

74. DETAIL VIEW OF INSIDE THE LAUNCHING BRIDGE LOOKING SOUTHWEST ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

74. DETAIL VIEW OF INSIDE THE LAUNCHING BRIDGE LOOKING SOUTHWEST SHOWING ADJUSTABLE STAIRS ON THE LEFT AND LAUNCHING TUBE ON THE RIGHT, Date unknown, circa 1948. - Variable Angle Launcher Complex, Variable Angle Launcher, CA State Highway 39 at Morris Reservior, Azusa, Los Angeles County, CA

Facial lacerations in children.

PubMed

Hwang, Kun; Huan, Fan; Hwang, Pil Joong; Sohn, In Ah

2013-03-01

The aim of this study was to evaluate the demographics and treatment of facial lacerations in pediatric patients. A retrospective record-based analysis was administered on 3783 patients (<15 years of age) presenting with facial lacerations from March 2002 to February 2011. Males were injured more frequently across all age groups (65.3%) and especially in the 13- to 15-year-old group (81.3%) (P = 0.012, Pearson χ). Overall, 48.9% of injuries occurred outdoors and 45.1% in homes. Only 6.0% occurred in schools or kindergartens. Injuries that occurred in schools or kindergarten increased with the age groups (from 2.3% for 0- to 3-year-olds to 19.1% for 13- to 15-year-olds). In the age groups younger than 12 years, injury occurred more frequently on the weekend. In the 13-to 15-year-old group, however, injury occurred more frequently on weekdays (odds ratio, 2.46). Injury occurred most frequently at the times of 7 to 9 PM and least frequently from midnight to 6 AM. The most frequent cause of injury in children was by being struck or by bumping something (32.5%), followed by slip-down (31.5%). Accidents involving furniture and stairs accounted for 9% each. Accidents caused by stairs decreased with age (from 10.2% for 0-3 years of age to 5.5% for 13-15 years of age, P = 0.000, Pearson χ). In a little less than half (47.2%) of the cases, parents accompanied their children at the time of injury. In the 13- to 15-year age group, only 17.9% of the children were accompanied by their parents. Foreheads (26.4%) took the brunt of most frequent injuries, followed by the eyelids (20.6%), eyebrows including the glabella (19.7%), and chin injuries (15.7%). Only 58 cases had associated injuries. Among 3783 cases of facial lacerations, 3745 patients did not have facial bone fractures or associated injuries and were managed under local anesthesia or through dressings only. A sound knowledge about the epidemiology of lacerations might be beneficial for the prevention of pediatric facial lacerations, which occurs more frequently than facial fractures. It is noteworthy that slip-down showed a peak in kindergarteners (4-6 years, 36.1%) and then decreased with age. The incidence of slip-down might be reduced if attention is paid when the kindergarteners are walking on steep stairs or steep flights of stairs. Injury at the educational institutions increases with the pupil's age, and therefore safety management in schools is important.

Associations among workplace environment, self-regulation, and domain-specific physical activities among white-collar workers: a multilevel longitudinal study.

PubMed

Watanabe, Kazuhiro; Kawakami, Norito; Otsuka, Yasumasa; Inoue, Shigeru

2018-05-31

Psychological and environmental determinants have been discussed for promoting physical activity among workers. However, few studies have investigated effects of both workplace environment and psychological determinants on physical activity. It is also unknown which domains of physical activities are promoted by these determinants. This study aimed to investigate main and interaction effects of workplace environment and individual self-regulation for physical activity on domain-specific physical activities among white-collar workers. A multi-site longitudinal study was conducted at baseline and about 5-month follow-up. A total of 49 worksites and employees within the worksites were recruited. Inclusion criteria for the worksites (a) were located in the Kanto area, Japan and (b) employed two or more employees. Employee inclusion criteria were (a) employed by the worksites, (b) aged 18 years or older, and (c) white-collar workers. For outcomes, three domain-specific physical activities (occupational, transport-related, and leisure-time) at baseline and follow-up were measured. For independent variables, self-regulation for physical activity, workplace environments (parking/bike, signs/bulletin boards/advertisements, stairs/elevators, physical activity/fitness facilities, work rules, written policies, and health promotion programs), and covariates at baseline were measured. Hierarchical Linear Modeling was conducted to investigate multilevel associations. Of the recruited worksites, 23 worksites and 562 employees, and 22 worksites and 459 employees completed the baseline and the follow-up surveys. As results of Hierarchical Linear Modeling, stairs/elevator (γ=3.80 [SE=1.80], p<0.05), physical activity/fitness facilities (γ=4.98 [SE=1.09], p<0.01), and written policies (γ=2.10 [SE=1.02], p<0.05) were significantly and positively associated with occupational physical activity. Self-regulation for physical activity was associated significantly with leisure-time physical activity (γ=0.09 [SE=0.04], p<0.05) but insignificantly with occupational and transport-related physical activity (γ=0.11 [SE=0.16] and γ=-0.00 [SE=0.06]). Significant interaction effects of workplace environments (physical activity/fitness facilities, work rules, and written policies) and self-regulation were observed on transport-related and leisure-time physical activity. Workplace environments such as physical activity/fitness facilities, written policies, work rules, and signs for stair use at stairs and elevators; self-regulation for physical activity; and their interactions may be effective to promote three domain-specific physical activities. This study has practical implications for designing multi-component interventions that include both environmental and psychological approaches to increase effect sizes to promote overall physical activity.

Short-term effects of 890-nanometer radiation on pain, physical activity, and postural stability in patients with knee osteoarthritis: a double-blind, randomized, placebo-controlled study.

PubMed

Hsieh, Ru-Lan; Lo, Min-Tzu; Liao, Wei-Cheng; Lee, Wen-Chung

2012-05-01

To investigate the effects of short-term light therapy with 890-nm radiation on pain, physical activity, and postural stability in patients with knee osteoarthritis (OA). A double-blind, randomized, placebo-controlled study. Rehabilitation clinic. Women (n=62) and men (n=10) with a mean age of 61.2 years (range, 40-88y). All patients fulfilled the combined clinical and radiographic criteria for knee OA as established by the American College of Rheumatology, and all had obtained a Kellgren-Lawrence score of 2 or more. Participants received 6 sessions, lasting 40 minutes each, of active or placebo radiation treatment over the knee joints for 2 weeks (wavelength, 890nm; radiant power output, 6.24W; power density, 34.7mW/cm(2) for 40 minutes; total energy, 41.6J/cm(2) per knee per session). Participants were assessed weekly over 4 weeks using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) for pain, stiffness, and physical function. Physical activity (timed stair climbing, 10-m fast-speed walking, and chair-rising time) and postural stability (using the postural stability evaluation system) were also assessed. The pain score on WOMAC was the primary outcome variable. Data were analyzed by repeated-measures analysis of covariance. Compared with baseline, no significant improvement was observed between groups for pain (P=.546), stiffness (P=.573), or physical function (P=.904). No significant improvement was noted for physical activity including the 10-m fast-speed walking time (P=.284), stair-climbing time (P=.202), stair-descending time (P=.468), chair-rising time (P=.499), or postural stability (P=.986) at the 4 follow-up assessments. Follow-up assessments were conducted after 1 week of treatment (thus, after 3 treatments); after 2 weeks of treatment (thus, after 6 treatments); and 1 and 2 weeks, respectively, after treatment was terminated. Although we found a significant time effect for the 10-m fast-speed walking time (P<.001) in the 2 groups, and a significant group effect in the improvement of stair-climbing time in the treatment group (P=.032), the group × time interaction effects were not significant. Short-term 890-nm radiation therapy for patients with knee OA provided no beneficial effect in improving pain, physical activity, and postural stability. Copyright © 2012 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

30. Historic American Buildings Survey, 1932 measured drawing from old ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

30. Historic American Buildings Survey, 1932 measured drawing from old Philadelphia Survey, 1897 measured drawing by C. L. Hillman and John McClintock, photocopy courtesy of the Free Library of Philadelphia MISCELLANEOUS DETAILS: INTERIOR DOORS, STAIRS, SOUTH ROOM CHIMNEY-PIECE, ENTRANCE HALL. - Woodford, Philadelphia, Philadelphia County, PA

5. Photograph of a photograph in possession of Rock Island ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. Photograph of a photograph in possession of Rock Island Arsenal Historical Office. SOUTH AND EAST ELEVATIONS AFTER ADDITION OF BRICK STAIR TOWERS ON SOUTH FACADE. DATED NOVEMBER 1, 1944. - Rock Island Arsenal, Building No. 110, Rodman Avenue between Fourth Street & East Avenue, Rock Island, Rock Island County, IL

5. Photograph of a photograph in possession of Rock Island ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. Photograph of a photograph in possession of Rock Island Arsenal Historical Office. SOUTH AND EAST ELEVATIONS AFTER ADDITION OF STAIR TOWERS ON SOUTH FACADE. DATED NOVEMBER 1, 1944. - Rock Island Arsenal, Building No. 104, Rodman Avenue between First & Second Streets, Rock Island, Rock Island County, IL

6. Keeper's house, first floor, detail of woodwork, looking northeast ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. Keeper's house, first floor, detail of woodwork, looking northeast from southwest room into northwest room and stair hall - Ram Island Light Station, Ram Island, south of Ocean Point & just north of Fisherman Island, marking south side of Fisherman Island Passage, Ocean Point, Lincoln County, ME

Interior building details of Building B, Room B004: south brick ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Interior building details of Building B, Room B-004: south brick wall partial painted brick plaster with stair scar trace, historic brick infilled arch entry way to Room C-001; southeasterly view - San Quentin State Prison, Building 22, Point San Quentin, San Quentin, Marin County, CA

10. PERSPECTIVE VIEW OF NORTH (REAR) AND WEST SIDE OF ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

10. PERSPECTIVE VIEW OF NORTH (REAR) AND WEST SIDE OF SECOND FLOOR, WEST ROOM SHOWING RELATIONSHIP TO NORTH TERREPLEIN OF NORTHWEST DEMI-BASTION AND STAIRS LEADING TO GUN MOUNT ABOVE MAIN GATE - Fort Washington, Main Gate, Fort Washington Road, Fort Washington Forest, Prince George's County, MD

49 CFR 27.72 - Boarding assistance for aircraft.

Code of Federal Regulations, 2011 CFR

2011-10-01

... assistance to individuals with disabilities using mechanical lifts, ramps, or other devices that do not require employees to lift or carry passengers up stairs. Paragraph (c) of this section applies to aircraft... to be unsuitable for boarding assistance by lift, ramp or other suitable device on the basis of a...

49 CFR 27.72 - Boarding assistance for aircraft.

Code of Federal Regulations, 2010 CFR

2010-10-01

... assistance to individuals with disabilities using mechanical lifts, ramps, or other devices that do not require employees to lift or carry passengers up stairs. Paragraph (c) of this section applies to aircraft... to be unsuitable for boarding assistance by lift, ramp or other suitable device on the basis of a...