scholarly journals Modulations of Foot and Ankle Frontal Kinematics for Breaking and Propulsive Movement Characteristics during Side-Step Cutting with Varying Midsole Thicknesses

2018 ◽  
Vol 2018 ◽  
pp. 1-8
Author(s):  
Yi-Jia Lin ◽  
Shih-Chi Lee ◽  
Chao-Chin Chang ◽  
Tsung-Han Liu ◽  
Tzyy-Yuang Shiang ◽  
...  
Keyword(s):  
Reaction Force ◽  
Human Movement ◽  
Foot And Ankle ◽  
Ankle Inversion ◽  
Movement Characteristics ◽  
Increased Risk ◽  
Spatial Performance ◽  
Movement Characteristic ◽  
The Stability ◽  
Excessive Stress

This study is aimed at determining the effects of midsole thickness on movement characteristic during side cutting movement. Fifteen athletes performed side-step cutting while wearing shoes with varying midsole thicknesses. Temporal-spatial and ground reaction force variables as well as foot and ankle frontal kinematics were used to describe breaking and propulsive movement characteristics and modulation strategies. Regardless of midsole thickness, temporal-spatial variables and breaking and propulsive force during side cutting were statistically unchanged. Significantly greater peaks of ankle inversion and plantarflexion with a thicker sole and greater midtarsal pronation with a thinner sole were observed. Current results demonstrated that hypotheses formed solely based on material testing were insufficient to understand the adaptations in human movement because of the redundancy of the neuromusculoskeletal system. Participants were able to maintain temporal-spatial performance during side cutting while wearing shoes with midsoles of varying thicknesses. Increased pronation for a thinner sole might help reduce the force of impact but might be associated with an increased risk of excessive stress on soft tissue. Increased peak of ankle inversion and plantarflexion for a thicker sole may be unfavorable for the stability of ankle joint. Information provided in human movement testing is crucial for understanding factors associated with movement characteristics and injury and should be considered in the future development of shoe design.

scholarly journals The kinematics of cyclic human movement

2019 ◽  
Author(s):  
Manfred M. Vieten ◽  
Christian Weich
Keyword(s):  
Human Movement ◽  
Human Motion ◽  
Treadmill Running ◽  
Data Driven ◽  
Movement Characteristics ◽  
Movement Characteristic ◽  
Cyclic Movement ◽  
Time Fluctuation ◽  
General Movement ◽  
Short Time

AbstractModels describing cyclic movement can roughly be divided into the categories theory or data driven. Theory driven models include anatomical and physiological aspects. They are principally suitable for answering questions about the reasons for movement characteristics. But, they are complicated and substantial simplifications do not allow generally valid results. Data driven models allow answering specific questions but lack the understanding of the general movement characteristic. With this paper we try a compromise not having to rely on anatomy, neurology and muscle function. We hypothesize a general kinematic description of cyclic human motion is possible without having to specify the movement generating processes, and still getting the kinematic right. The model proposed consisting of a superposition of six contributions – subject’s attractor, morphing, short time fluctuation, transient effect, control mechanism and sensor noise -, with characterizing numbers and random contributions. We test the model with data form treadmill running and stationary biking. Applying the model in form of a simulation results in good agreement between measured data and simulation values.

scholarly journals Characteristic time in highly motivated movements of children and adults through bottlenecks

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hongliu Li ◽  
Jun Zhang ◽  
Long Xia ◽  
Libing Yang ◽  
Weiguo Song ◽  
...  
Keyword(s):  
Relaxation Time ◽  
School Children ◽  
Characteristic Time ◽  
Building Design ◽  
Activation Time ◽  
Density Region ◽  
Time Motion ◽  
Movement Characteristics ◽  
Movement Characteristic ◽  
The Difference

AbstractCurrent codes for fire protection of buildings are mainly based on the movement of adults and neglect the movement characteristic of pre-school children. Having a profound comprehension of the difference between children and adults passing bottlenecks is of great help to improve the safety levels of preschool children. This paper presents an experimental study on the bottleneck flow of pre-school children in a room. The movement characteristics of children’s and adults’ bottleneck flow are investigated with two macroscopic properties: density and speed profiles as well as microscopic characteristic time: motion activation time, relaxation time, exit travel time and time gap. Arch-like density distributions are observed both for highly motivated children and adults, while the distance between the peak density region and the exit location is shorter for children and longer for adults. Children’s movement is less flexible manifested as longer motion activation time and longer relaxation time compared to that of adults. The findings from this study could enhance the understanding of crowd dynamics among the children population and provide supports for the scientific building design for children’s facilities.

scholarly journals Ensemble model for estimating continental-scale patterns of human movement: a case study of Australia

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Karen McCulloch ◽  
Nick Golding ◽  
Jodie McVernon ◽  
Sarah Goodwin ◽  
Martin Tomko
Keyword(s):  
Spatial Scales ◽  
Predictive Ability ◽  
Movement Patterns ◽  
Human Movement ◽  
Continental Scale ◽  
Movement Characteristics ◽  
Human Movements ◽  
Movement Models ◽  
Epidemiology Data

AbstractUnderstanding human movement patterns at local, national and international scales is critical in a range of fields, including transportation, logistics and epidemiology. Data on human movement is increasingly available, and when combined with statistical models, enables predictions of movement patterns across broad regions. Movement characteristics, however, strongly depend on the scale and type of movement captured for a given study. The models that have so far been proposed for human movement are best suited to specific spatial scales and types of movement. Selecting both the scale of data collection, and the appropriate model for the data remains a key challenge in predicting human movements. We used two different data sources on human movement in Australia, at different spatial scales, to train a range of statistical movement models and evaluate their ability to predict movement patterns for each data type and scale. Whilst the five commonly-used movement models we evaluated varied markedly between datasets in their predictive ability, we show that an ensemble modelling approach that combines the predictions of these models consistently outperformed all individual models against hold-out data.

Preoperative Risk Factors for Complications in Elective Ankle and Hindfoot Reconstruction

2017 ◽  
Vol 11 (1) ◽  
pp. 54-60 ◽  
Author(s):  
Ryan P. Mulligan ◽  
Kevin J. McCarthy ◽  
Benjamin J. Grear ◽  
David R. Richardson ◽  
Susan N. Ishikawa ◽  
...  
Keyword(s):  
Risk Factors ◽  
Retrospective Chart Review ◽  
Reoperation Rate ◽  
Deep Infection ◽  
Foot And Ankle ◽  
Psychological Variables ◽  
Reconstruction Methods ◽  
Increased Risk ◽  
Retrospective Comparative Study ◽  
Alcohol Users

Background. The purpose of this study was to examine medical, social, and psychological factors associated with complications and reoperation after foot and ankle reconstruction. Methods. A retrospective chart review was conducted of 132 patients (135 feet; 139 operative cases) who had elective foot and ankle reconstruction. Medical, social, and psychological variables were documented. Primary outcomes included complications and reoperations. Results. The overall complication rate was 28% (39/139), and the reoperation rate was 17% (24/139). Alcohol use (P = .03) and preoperative narcotic use (P = .02) were risk factors for complications, with delayed wound healing more frequent in alcohol users (P = .03) and deep infection (P = .045) and nonunion (P = .046) more frequent preoperative narcotic use. Deep infection also was more frequent in tobacco users (P < .01). Older patients were less likely to undergo reoperation (risk of reoperation increased with age). Other variables were not associated with increased complications. Conclusion. Patients who consumed alcohol or had been prescribed any amount of narcotic within 3 months preoperatively were at increased risk for complications. Patients who smoked were more likely to have a wound infection. Surgeons should be aware of these factors and counsel patients before surgery. Levels of Evidence: Level III: Retrospective comparative study

Effect of Hopping Frequency on Bilateral Differences in Leg Stiffness

2013 ◽  
Vol 29 (1) ◽  
pp. 55-60 ◽  
Author(s):  
Hiroaki Hobara ◽  
Koh Inoue ◽  
Kazuyuki Kanosue
Keyword(s):  
Ground Reaction Force ◽  
Center Of Mass ◽  
Reaction Force ◽  
Human Movement ◽  
Vertical Ground Reaction Force ◽  
Mass Model ◽  
Lower Extremity Injuries ◽  
Leg Stiffness ◽  
Significant Difference ◽  
Bilateral Differences

Understanding the degree of leg stiffness during human movement would provide important information that may be used for injury prevention. In the current study, we investigated bilateral differences in leg stiffness during one-legged hopping. Ten male participants performed one-legged hopping in place, matching metronome beats at 1.5, 2.2, and 3.0 Hz. Based on a spring-mass model, we calculated leg stiffness, which is defined as the ratio of maximal ground reaction force to maximum center of mass displacement at the middle of the stance phase, measured from vertical ground reaction force. In all hopping frequency settings, there was no significant difference in leg stiffness between legs. Although not statistically significant, asymmetry was the greatest at 1.5 Hz, followed by 2.2 and 3.0 Hz for all dependent variables. Furthermore, the number of subjects with an asymmetry greater than the 10% criterion was larger at 1.5 Hz than those at 2.2 and 3.0 Hz. These results will assist in the formulation of treatment-specific training regimes and rehabilitation programs for lower extremity injuries.

A New Lower Extremity Modeling of Human Body With Variable Feet Links

2000 ◽  
Author(s):  
Nader Arafati ◽  
Jean Yves Lazennec ◽  
Roger Ohayon
Keyword(s):  
Ground Reaction Force ◽  
Sagittal Plane ◽  
Reaction Force ◽  
Human Movement ◽  
Knee Joints ◽  
Foot Pressure ◽  
Ankle Joints ◽  
Reaction Forces ◽  
Human Movement Modeling ◽  
Force Vectors

Abstract Human movement modeling has been the object of much research for the past 30 years. In these models the position of foot link was fixed on the ground. We propose to model the feet links as variable, since the position of foot pressure center changes from heel to toes. The ground reaction forces could also be analyzed in real time. We examined this model for some static postures. In standing anatomical position, the maximum articular forces are localized in hip and knee joints. In sagittal plane, the ground reaction force vectors are positioned nearly under ankle joints. The pathological postures like body with pes cavus or with global spine kyphosis increase the articular and muscular forces. In these cases, the position of ground reaction force vectors is moved toward the toes.

Parental Behavior of Adolescent Mothers

PEDIATRICS ◽  
1983 ◽  
Vol 71 (4) ◽  
pp. 494-503
Author(s):  
Arthur B. Elster ◽  
Elizabeth R. McAnarney ◽  
Michael E. Lamb
Keyword(s):  
Adolescent Mothers ◽  
Adolescent Parents ◽  
Intellectual Development ◽  
Parental Behavior ◽  
Support Network ◽  
Child Rearing ◽  
Adolescent Parenting ◽  
Adequate Knowledge ◽  
Increased Risk ◽  
Excessive Stress

The results of the studies reviewed lead to the conclusion that some adolescent parents are faced with excessive stress, have an inadequate social support network, lack adequate knowledge of child development, are developmentally immature, and possess inappropriate child-rearing attitudes. The lack of rigorous, well-controlled studies, however, makes these conclusions tentative at best. Each of the socioeconomic and psychological factors listed above, in addition to innate infant characteristics, affects parental behavior. Too few studies have been done to state conclusively which of these factors have major effects on adolescent parenting. Preliminary results would suggest, however, that adolescent and adult mothers interact differently with their children. The reasons why this occurs and the significance of this difference are not presently known. Although there are conflicting results, it appears as though children of adolescent parents are at a slightly increased risk for child abuse, but not suboptimal intellectual development, when compared to children of adult mothers.

scholarly journals Subsequent Injury is Common after Foot and Ankle Surgery in Patients Receiving Workers’ Compensation

2018 ◽  
Vol 3 (3) ◽  
pp. 2473011418S0017
Author(s):  
Gabrielle Bui ◽  
Phinit Phisitkul ◽  
Natalie Glass ◽  
Chris Cychosz ◽  
Sean Boarini
Keyword(s):  
Retrospective Chart Review ◽  
Anatomical Location ◽  
Workers Compensation ◽  
Foot And Ankle ◽  
Chi Square ◽  
Legal Representation ◽  
Increased Risk ◽  
Ankle Surgery ◽  
Poor Outcomes ◽  
Subsequent Injury

Category: Ankle Introduction/Purpose: Workers’ compensation (WC) has been associated with poor outcomes following a variety of injuries and surgeries. Previous studies have investigated surgical outcomes via satisfaction surveys, but rates of subsequent injury following surgery have not been specifically studied. The purpose of this study was to investigate the rates, locations and risk factors for subsequent injuries in WC patients and non-WC patients who underwent the same surgeries. Methods: With IRB approval, we identified the records of patients with a foot or ankle surgery performed by a single surgeon from 2009-2015. We included only surgeries with one of the most common current procedural terminology (CPT) codes from the WC population. A retrospective chart review was performed on all WC and non-WC patients with at least one of these CPT codes. A subsequent injury was defined as a new injury at a different anatomical location that occurred from 2 months to 2 years after the index surgery. Chi-square and two-tailed t-tests were used to compare WC and non-WC patient populations, and to determine factors associated with subsequent injuries. Results: Overall, the WC population had higher rates of subsequent injury than the non-WC population 23.21% versus 7.27%, p=.0011. Within the WC patient population, patients with subsequent injuries were older than patients without subsequent injuries 48.78±7.30 versus 41.58±12.40, p=.0137. In a blinded review of the charts and Iowa Courts Online, legal representation was found to be more common in WC patients with subsequent injuries than WC patients without subsequent injuries (76.92% versus 37.21%, p=.0240). In the non-WC population, there were more males in the group without subsequent injuries than in the group with subsequent injuries 42.48% versus 8.33%, p=.0287. There were no significant differences in locations of subsequent injury. Hip, knee and contralateral foot and ankle were common areas of subsequent injury in both groups. Conclusion: Overall, WC patients had higher rates of subsequent injury than non-WC patients. Within the WC group, legal representation further raised the risk of subsequent injury. Gender may mediate variable reporting of subsequent injuries in non-WC populations. While the reason for this increased risk of subsequent injury is not known, the differences are enough that they should be considered when counseling WC patients considering these surgeries. Additionally, if further study supported these findings, knowledge of the areas at risk for subsequent injury might lead to preventative strategies that could decrease the risk of subsequent injury.

scholarly journals Incidence of Venous Thromboembolism in Orthopaedic Foot and Ankle Surgeries

2018 ◽  
Vol 3 (3) ◽  
pp. 2473011418S0010
Author(s):  
Ashish Shah ◽  
Samuel Huntley ◽  
Harshadkumar Patel ◽  
Eildar Abyar ◽  
Eva Lehtonen ◽  
...  
Keyword(s):  
Venous Thromboembolism ◽  
Elective Surgery ◽  
Meta Analysis ◽  
Categorical Variables ◽  
Continuous Variables ◽  
Foot And Ankle ◽  
Improvement Program ◽  
Female Sex ◽  
Increased Risk ◽  
Ankle Surgery

Category: Other Introduction/Purpose: Venous thromboembolism (VTE) is a rare but potentially lethal complication following orthopaedic foot and ankle surgery. Surgeons continue to debate the types of patients and procedures in which it is appropriate to use chemical thromboprophylaxis. A recent meta-analysis concluded that patients at high risk for VTE after foot and ankle surgery should receive prophylaxis, but there remains a paucity of data to elucidate which demographic or comorbidity variables are most strongly associated with development of VTE. The incidence of VTE after orthopaedic foot and ankle surgery stratified by specific procedure has yet to be examined. The purpose of this study is to report the incidence of and identify risk factors for VTE in a large sample of patients receiving orthopaedic foot and ankle surgery. Methods: In this study, we retrospectively analyzed prospectively-collected data from the National Surgical Quality Improvement Program (NSQIP) 2006 to 2015 data files. The incidence of VTE was calculated for 30 specific orthopaedic foot and ankle surgeries and for four broad types of foot and ankle surgery. A total of 23,212 patients were identified and grouped by current procedures terminology (CPT) codes. Demographic, comorbidity, and complication variables were analyzed to determine associations with development of VTE. Pearson’s chi-squared test was used to compare categorical variables and Student t test was used to compare continuous variables. P-values of p<0.05 were considered statistically significant. Multivariable modelling was not possible due to the very low number of VTE cases relative to non-VTE cases. Results: The mean age at the time of surgery was 52.7±17.8 years. VTE events were documented 142 times in our sample, yielding an overall sample VTE incidence of 0.6%. The types of procedures with the highest frequency of VTE were ankle fractures (105/15,302 cases, 0.7%), foot pathologies (28/5,466, 0.6%), and arthroscopy (2/398, 0.5%). Female sex, increasing age, obesity level, inpatient status, and non-elective surgery were all significantly associated with VTE events. Postoperative pneumonia was significantly associated with VTE development. Patients who developed a VTE stayed at the hospital after surgery significantly longer than patients without VTE (6.2 vs. 3.1 days). Patients who developed VTE also had significantly higher estimated probability of morbidity (8.0% vs. 6.0%) and mortality (2.0% vs. 1.0%) when compared to patients without VTE. Conclusion: The present study confirms that VTE events after foot and ankle procedures are rare. The data presented suggest that female sex, increasing age, higher BMI, inpatient status, and non-elective procedures are associated with increased risk for VTE after orthopaedic foot and ankle surgery. Prospective, randomized, controlled trials are necessary to definitively determine the efficacy of chemoprophylaxis and to develop evidence-based clinical practice guidelines to minimize VTE after foot and ankle procedures.

What Can a Jump Tell Us About Elbow Injuries in Professional Baseball Pitchers?

2020 ◽  
Vol 48 (5) ◽  
pp. 1220-1225
Author(s):  
John Mayberry ◽  
Scott Mullen ◽  
Scott Murayama
Keyword(s):  
Test Performance ◽  
Injury Risk ◽  
Reaction Force ◽  
Professional Baseball ◽  
Shoulder Injury ◽  
Injury Rates ◽  
Elbow Injury ◽  
Increased Risk ◽  
Elbow Injuries ◽  
Baseball Pitchers

Background: The incidence rate of elbow injuries has been rising in recent years among professional baseball pitchers. Determining valid screening procedures that allow practitioners to identify pitchers at an increased risk of such injuries is therefore of critical importance. Purpose: To validate the use of countermovement jump (CMJ) tests as a diagnostic tool for pitcher conditioning. Study Design: Case-control study; Level of evidence, 3. Methods: More than 500 pitchers at a single professional baseball organization performed preseason CMJ assessments on a force plate before the 2013 to 2018 seasons. Three measurements were extracted from ground-reaction force data during the test: eccentric rate of force development (ERFD), average vertical concentric force (AVCF), and concentric vertical impulse (CVI). Athletic trainers at the organization collected detailed information on elbow and shoulder injury rates as well as workload (pitch count) throughout the rest of the season. Poisson regression models were fit to investigate the dependency of injury rates on CMJ test performance. Results: ERFD, CVI, and AVCF were all significant predictors of elbow injury risk after accounting for pitcher age, weight, and workload. The analysis identified 3 specific indicators of heightened risk based on the results of a CMJ scan: low ERFD, a combination of low AVCF and high CVI, and a combination of high AVCF and low CVI. In contrast, shoulder injury risk was roughly independent of all 3 CMJ test measurements. Conclusion: This study supports the hypothesis of the entire kinetic chain’s involvement in pitching by establishing a link between CMJ test performance and elbow injury risk in professional baseball pitchers. CMJ assessment may be a powerful addition to injury risk alert and prevention protocols. Pitchers in high-risk groups can be prescribed specific exercise plans to improve movement imbalances.

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