scholarly journals Contributions of Limb Joints to Energy Absorption during Landing in Cats

2019 ◽  
Vol 2019 ◽  
pp. 1-13 ◽  
Author(s):  
Xueqing Wu ◽  
Baoqing Pei ◽  
Yuyang Pei ◽  
Nan Wu ◽  
Kaiyuan Zhou ◽  
...  
Keyword(s):  
Energy Absorption ◽  
Inverse Dynamics ◽  
Motor Program ◽  
Lower Limbs ◽  
Joint Angles ◽  
Limb Injuries ◽  
Significant Difference ◽  
Angular Velocities ◽  
Synergistic Mechanism ◽  
The Impact

There is a high risk of serious injury to the lower limbs in a human drop landing. However, cats are able to jump from the same heights without any sign of injury, which is attributed to the excellent performance of their limbs in attenuating the impact forces. The bionic study of the falling cat landing may therefore contribute to improve the landing-shock absorbing ability of lower limbs in humans. However, the contributions of cat limb joints to energy absorption remain unknown. Accordingly, a motion capture system and plantar pressure measurement platform were used to measure the joint angles and vertical ground reaction forces of jumping cats, respectively. Based on the inverse dynamics, the joint angular velocities, moments, powers, and work from different landing heights were calculated to expound the synergistic mechanism and the dominant muscle groups of cat limb joints. The results show that the buffering durations of the forelimbs exhibit no significant difference with increasing height while the hindlimbs play a greater role than the forelimbs in absorbing energy when jumping from a higher platform. Furthermore, the joint angles and angular velocities exhibit similar variations, indicating that a generalized motor program can be adopted to activate limb joints for different landing heights. Additionally, the elbow and hip are recognized as major contributors to energy absorption during landing. This experimental study can accordingly provide biological inspiration for new approaches to prevent human lower limb injuries.

Computed tomography angiography and microsurgical flaps for traumatic wounds: What is the added value?

2021 ◽  
pp. 1-9
Author(s):  
Lucas Sousa Macedo ◽  
Renato Polese Rusig ◽  
Gustavo Bersani Silva ◽  
Alvaro Baik Cho ◽  
Teng Hsiang Wei ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Upper Limb ◽  
Computed Tomography Angiography ◽  
Lower Limb ◽  
High Energy ◽  
Lower Limbs ◽  
Added Value ◽  
Vascular Lesions ◽  
Limb Injuries ◽  
Significant Difference

BACKGROUND: Microsurgical flaps are widely used to treat complex traumatic wounds of upper and lower limbs. Few studies have evaluated whether the vascular changes in preoperative computed tomography angiography (CTA) influence the selection of recipient vessel and type of anastomosis and the microsurgical flaps outcomes including complications. OBJECTIVE: The aim of this study was to evaluate if preoperative CTA reduces the occurrence of major complications (revision of the anastomosis, partial or total flap failure, and amputation) of the flaps in upper and lower limb trauma, and to describe and analyze the vascular lesions of the group with CTA and its relationship with complications. METHODS: A retrospective cohort study was undertaken with all 121 consecutive patients submitted to microsurgical flaps for traumatic lower and upper limb, from 2014 to 2020. Patients were divided into two groups: patients with preoperative CTA (CTA+) and patients not submitted to CTA (CTA–). The presence of postoperative complications was assessed and, within CTA+, we also analyzed the number of patent arteries on CTA and described the arterial lesions. RESULTS: Of the 121 flaps evaluated (84 in the lower limb and 37 in the upper limb), 64 patients underwent preoperative CTA. In the CTA+ group, 56% of patients with free flaps for lower limb had complete occlusion of one artery. CTA+ patients had a higher rate of complications (p = 0.031), which may represent a selection bias as the most complex limb injuries and may have CTA indicated more frequently. The highest rate of complications was observed in chronic cases (p = 0.034). There was no statistically significant difference in complications in patients with preoperative vascular injury or the number of patent arteries. CONCLUSIONS: CTA should not be performed routinely, however, CTA may help in surgical planning, especially in complex cases of high-energy and chronic cases, since it provides information on the best recipient artery and the adequate level to perform the microanastomosis, outside the lesion area.

scholarly journals Influence of Mild Peripheral Arterial Obstructive Disease in the Functional Capacity

2019 ◽  
Vol 21 (3) ◽  
pp. 225
Author(s):  
Eduardo Brandão Azevedo ◽  
Keila De Castro Marinho Azevedo ◽  
Inácio Teixeira da Cunha Filho ◽  
Rodrigo Nicolato
Keyword(s):  
Physical Fitness ◽  
Intermittent Claudication ◽  
Functional Capacity ◽  
Lower Limbs ◽  
Control Group ◽  
Obstructive Disease ◽  
Significant Difference ◽  
Peripheral Arterial Obstructive Disease ◽  
Peripheral Arterial ◽  
The Impact

AbstractThe peripheral arterial obstructive disease (PAOD) is a chronic illnes that has as main symptom intermittent claudication and causes a progressive functional impairment of the patient. The literature is still inconclusive when it addresses the relationship among functional capacity, endurance, muscle contraction speed, and degree of blood flow impairment in patients with PAOD. The objective of this study was to evaluate the physical fitness individuals with bilateral PAOD, claudication and ankle-brachial index between 0.8 and 0.9, to verify the impact of the disease in this outcome and to analyze the association among the tests. Forty individuals, with mean age 56 years were divided in: group PAOD (n=20) and control group (n=20) were subjected to the following tests: Five-Times-Sit-to-Stand Test (FTSST), Heel-rise test (HRT), test of gait speed usual (UV) and maximum (MV), shuttle walking test (SWT). There was a significant difference among the variables obtained through HRT, UV, MV and SWT, showing a worse performance of the group with PAOD compared to the control. The FTSST test showed no differences among the groups. Analyzing the whole sample, the presence of PAOD is an indicator of poor performance in TDBP. This study suggests that people with mild PAOD present reduced performance in functional endurance tests of the lower limbs and that there is a direct relationship between walking speed and patency of local arterial flow, demonstrating in an unprecedented way the need for evaluation of this public, considering the possibility of initial identification of the symptoms and giving greater efficiency in the therapeutic planning of maintenance of the functionality.Keywords: Physical Fitness. Intermittent Claudication. Peripheral Vascular Diseases.ResumoA doença arterial obstrutiva periférica (DAOP) é uma doença crônica que tem como sintoma principal a claudicação intermitente e causa um progressivo comprometimento funcional do paciente. A literatura ainda é inconclusiva quando aborda a relação entre a capacidade funcional, endurance, velocidade de contração muscular e grau de comprometimento de fluxo sanguíneo em pacientes com DAOP. O objetivo deste estudo foi avaliar a aptidão física de indivíduos com DAOP bilateral, claudicantes e Índice tornozelo-braço entre 0,8 e 0,9, verificar o impacto da doença neste desfecho e analisar a associação entre os testes. Quarenta indivíduos, com faixa etária média de 56 anos, divididos em grupo DAOP (n=20) e grupo controle (n=20), foram submetidos aos testes: Teste senta-levanta (TSL), teste ponta de pé (TPP), testes de velocidade usual (VU) e máxima (VM), teste de deslocamento bidirecional progressivo (TDBP). Houve diferença significativa entre as variáveis do TPP, VU, VM e TDBP, mostrando pior performance do grupo com DAOP comparado ao controle. O teste TSL não apresentou diferença entre os grupos. Analisando os grupos em conjunto a presença de DAOP foi indicadora de pior desempenho no TDBP. Este estudo sugere que pacientes com DAOP leve apresentam redução da performance nos testes funcionais de endurance dos membros inferiores e que existe uma relação direta entre a velocidade da marcha e a patência do fluxo arterial local, demonstrando de forma inédita, a necessidade de avaliação deste público, considerando a possibilidade de identificação inicial dos sintomas e conferindo maior eficiência no planejamento terapêutico de manutenção da funcionalidade.Palavras-chave: Aptidão Física. Claudicação Intermitente. Doenças Vasculares Periféricas.

Initial balance in human standing postures: Roles of the joint mechanisms

2018 ◽  
Vol 232 (12) ◽  
pp. 1255-1260 ◽  
Author(s):  
Mohammed N Ashtiani ◽  
Mahmood-reza Azghani ◽  
Mohamad Parnianpour
Keyword(s):  
Inverse Dynamics ◽  
Muscular Activity ◽  
Biomechanical Model ◽  
Lower Limbs ◽  
Stable Set ◽  
Joint Angles ◽  
Lower Extremity Muscle ◽  
Ankle Muscles ◽  
Muscle Groups ◽  
Dynamics Method

The static initial postures of standing before applying perturbations may affect the maintenance of postural balance. The goal of this article was to find the stable set of postures and then determine the roles of joint mechanisms. The set of posture was defined in a biomechanical model based on three joint angles of the lower limbs. Optimized inverse dynamics method was used to solve for muscle forces in a precise model of the human musculoskeletal system posed in 4096 static sets of posture using AnyBody software. Results showed that the overall body muscular activity in standing is reduced by knee flexion. Moderate knee angles between 20° and 60° provided safer postures against possible perturbations because of higher collaboration levels of the joint mechanisms. About 36% of the overall postural infeasibilities were attributed to the inability of the ankle muscles to more sustain the exerted loads. Although the roles of the joint mechanisms were closely dependent on the postures, there was no direct relation between the joint kinematics and activation levels of their supporting muscles. Lower extremity muscle groups collaborate to maintain the balance in a considerable number of static postures.

scholarly journals Effects of active muscle forces on driver’s lower-limb injuries due to emergency brake in various frontal impacts

2019 ◽  
Vol 234 (7) ◽  
pp. 2014-2024
Author(s):  
Fan Li ◽  
Wei Huang ◽  
Xingsheng Wang ◽  
Xiaojiang Lv ◽  
Fuhao Mo
Keyword(s):  
Muscle Contraction ◽  
Lower Limb ◽  
Injury Risk ◽  
Muscle Activation ◽  
Bending Moment ◽  
Lower Limbs ◽  
Lower Limb Injuries ◽  
Lower Limb Injury ◽  
Limb Injuries ◽  
The Impact

Accident data shows that driver’s kinematics response in real accidents can be significantly different from that in dummy or cadaver tests because of driver’s muscle contraction. In this study, a finite element human-body model consisting of an upper body of a dummy model and a lower limb–pelvis biomechanical model with three-dimensional active muscles was developed to investigate in depth the lower-limb injuries. Driver’s emergency reaction during frontal impact was simulated by modelling muscle active contraction based on a series of volunteer experimental tests. Besides, a realistic impact environment with the response of the restraint system and the invasion of the driver’s compartment was established in this study. The results show that muscle contraction can cause extra loads on lower limbs during the impact, which can increase the injury risk of lower limbs. As for the femur injury, muscle contraction caused an additional 1 kN axial load on the femur, and the femur resultant bending moment of active models was also higher by about 10–40 N m. Besides, the tibial index of the model with muscle activation was about 0.1 higher. In addition, the results indicate that the femur injury is strongly related to the combined action of both axial force and bending moment. The variation of the injury tolerance along the tibia shaft should be considered when evaluating the tibia injury. Overall, the current lower-limb injury criteria can be still the lack of robustness.

scholarly journals The Effect of Corrective Feedback Exercise on Knee Kinematics and EMG of Lower Limbs of Female Wushu Players

2021 ◽  
Author(s):  
Fahimeh Rashidi ◽  
Abdolrasoul Daneshjoo ◽  
Seyed Kazem Mousavi Sadati
Keyword(s):  
Lower Limb ◽  
Corrective Feedback ◽  
Exercise Group ◽  
T Test ◽  
Lower Limbs ◽  
Control Group ◽  
Limb Injuries ◽  
Significant Difference ◽  
Post Test ◽  
Feedback Correction

Introduction: Recent studies have examined the risk factors associated with lower limb injuries. This study aimed to explore the effect of 12 sessions of feedback corrective exercises on the kinematic indicators of the knee and the Electromyography Activity (EMG) of the muscles of the lower limbs of female wushu players. The present study has a quasi-experimental design with a pre-test/post-test design and a control group. Materials and Methods: In this study, 16 female wushu players were selected by the available sampling method and placed in two groups of exercise and control. The exercise group performed feedback correction exercises for 12 sessions. Before and after the knee varus exercises, we measured, pelvic drop, and EMG of the lower limb muscles of both groups     in the SLS movement. The independent two-sample t-test was used to examine intergroup differences and the two-group correlated t-test was used to compare intra group sizes. To analyze the statistical data, SPSS V. 23 was used (P≤0.05) Results: The results showed a significant difference in knee varus between the experiment group and the control group in the pre-test and there was a significant difference between the pelvic drop in the pre-test and post-test of the experiment group compared with the control. The angle of the knee varus in the exercise group showed a significant difference with the control group. The EMG results of the muscles in the pre-test and post-test were significantly different. Conclusion: Based on the findings of the present study, the feedback correction exercise may improve motion control in wushu players. It also improved neuromuscular weakness in the subjects. According to the results and based on less muscle activity during movements, this exercise will reduce fatigue and the risk of injury.

scholarly journals Evaluation of prognostic predictors of mangled extremity severity scoring system on the outcome of traumatic extremities injuries at emergency department in Suez Canal University Hospitals

2016 ◽  
Vol 4 (1) ◽  
pp. 75 ◽  
Author(s):  
Ahmed A. Essa ◽  
Islam M. El-Shaboury ◽  
Yasmin E. El-Beltagy
Keyword(s):  
Emergency Department ◽  
Severity Score ◽  
Scoring System ◽  
Suez Canal ◽  
Lower Limbs ◽  
University Hospital ◽  
Severity Scoring ◽  
Mangled Extremity ◽  
Limb Injuries ◽  
Significant Difference

Background:Severe traumatic lower limbs injuries have been associated with high incidence of multiple systems involved (integument, nerve, bone, and vascular structures). That’s make difficulty and stress on surgeon’s decision making either to amputate or preserve the injured limbs. The Mangled Extremity Severity Score (MESS) was developed in Seattle (Johansen et al), based on both retrospective and prospective analysis of admission data of patients with severe limb injuries. The objective of this study was to evaluation of the prognostic predicting factors of outcome of traumatic extremities patients using Mangled Severity Scoring System at Emergency Department in Suez Canal University Hospital in order to help surgeon to make decision either to preserve or to amputate.Methods: This is a descriptive study (cross sectional), conducted on 60 patients with severe extremities injuries that met the criteria of the Mangled Extremity Severity Scoring attending to the Emergency Department (ED) at Suez Canal University Hospital.Results:This study showed that 83.33% of the patients had associated fractures, 8.33% of them had pneumothorax, 5% of them had abdominal collection and 3.33% of them had brain injuries. This study showed that 75% of the studied patients had MESS less than 7 while 25% of them had MESS > or = 7. The Mangled scoring system was a good predictor of amputation among the studied patients with sensitivity of 71.4%, specificity of 100% and 90% accuracy.Conclusions:Most of the patients had Mangled Extremity Severity Score less than 7. The MESS showed statistically significant difference between the amputated and the not amputated patients with 90% accuracy in prediction of amputation.

Measuring Impact of Stress in Sandwich Generation Caring for Demented Parents

GeroPsych ◽  
2014 ◽  
Vol 27 (4) ◽  
pp. 171-179 ◽  
Author(s):  
Laurence M. Solberg ◽  
Lauren B. Solberg ◽  
Emily N. Peterson
Keyword(s):  
Factor Analysis ◽  
Exploratory Factor Analysis ◽  
Social Worker ◽  
Resource Availability ◽  
Well Being ◽  
Sandwich Generation ◽  
Item Questionnaire ◽  
Significant Difference ◽  
Adult Caregivers ◽  
The Impact

Stress in caregivers may affect the healthcare recipients receive. We examined the impact of stress experienced by 45 adult caregivers of their elderly demented parents. The participants completed a 32-item questionnaire about the impact of experienced stress. The questionnaire also asked about interventions that might help to reduce the impact of stress. After exploratory factor analysis, we reduced the 32-item questionnaire to 13 items. Results indicated that caregivers experienced stress, anxiety, and sadness. Also, emotional, but not financial or professional, well-being was significantly impacted. There was no significant difference between the impact of caregiver stress on members from the sandwich generation and those from the nonsandwich generation. Meeting with a social worker for resource availability was identified most frequently as a potentially helpful intervention for coping with the impact of stress.

Implicit and explicit corrective feedback and feedback exposure conditions

2020 ◽  
Vol 4 (1) ◽  
pp. 3-48
Author(s):  
Takehiro Iizuka ◽  
Kimi Nakatsukasa
Keyword(s):  
Explicit Knowledge ◽  
Corrective Feedback ◽  
Significant Difference ◽  
Oral Corrective Feedback ◽  
Post Test ◽  
Picture Description ◽  
Potential Factors ◽  
Implicit And Explicit ◽  
Instructional Settings ◽  
The Impact

This exploratory study examined the impact of implicit and explicit oral corrective feedback (CF) on the development of implicit and explicit knowledge of Japanese locative particles (activity de, movement ni and location ni) for those who directly received CF and those who observed CF in the classroom. Thirty-six college students in a beginning Japanese language course received either recast (implicit), metalinguistic (explicit) or no feedback during an information-gap picture description activity, and completed a timed picture description test (implicit knowledge) and an untimed grammaticality judgement test (explicit knowledge) in a pre-test, immediate post-test and delayed post-test. The results showed that overall there was no significant difference between CF types, and that CF benefited direct and indirect recipients similarly. Potential factors that might influence the effectiveness of CF, such as instructional settings, complexity of target structures and pedagogy styles, are discussed.

Reducing the Social Stigma Associated with Obsessive Compulsive Disorder: A Controlled Trial of an Intervention Program in a Turkish Community Sample

2020 ◽  
Vol 20 (2) ◽  
pp. 101-120
Author(s):  
Ayça Aktaç Gürbüz ◽  
Orçun YORULMAZ ◽  
Gülşah DURNA
Keyword(s):  
Obsessive Compulsive Disorder ◽  
Intervention Program ◽  
Controlled Trial ◽  
Community Sample ◽  
Case Vignette ◽  
Control Group ◽  
Obsessive Compulsive ◽  
Compulsive Disorder ◽  
Significant Difference ◽  
The Impact

Scientific research into the reduction of stigmatization, particularly related to specific problems such as Obsessive-Compulsive Disorder (OCD), is scarce. In the present study, we examine the impact of a video-based antistigma intervention program for OCD in a pretest-posttest control group research. After being randomly assigned to either an intervention (n= 101) or control group (n= 96), the participants reported their attitudes on a hypothetical case vignette before and after OCD vs. Multiple Sclerosis (MS) videos, and again six months later as a follow up assessment. The mixed design analyses for the group comparisons indicated that although there was no significant difference in the measures of the control group, the participants watching the anti-stigma OCD video, in which the focus was psychoeducation and interaction strategies, reported significantly lower scores on social distances and negative beliefs for the case vignettes they read, and this difference was maintained six months later. Then, the present results indicate the effectiveness of our anti-stigma intervention program for OCD. Interventions to reduce stigmatization can also be viewed as effective tools for changing the attitudes of people toward OCD, although further research and applications are needed related to specific disorders if a longlasting impact is to be achieved.

Antecedents And Outcomes Of Qwl Among Employees In Banks

2019 ◽  
Vol 118 (7) ◽  
pp. 1-19
Author(s):  
Geethanjali N ◽  
Parveen Roja M ◽  
Lavanya D
Keyword(s):  
Organizational Climate ◽  
Job Stress ◽  
Work Life ◽  
Working Environment ◽  
Quality Of Work Life ◽  
Quality Of Work ◽  
Significant Difference ◽  
Service Productivity ◽  
The Impact

Quality of work life is the major factor to be considered in working environment of any organization. The performance of employees and the organization lies on the ability of the employees based on working environment. The QWL leads to better working environment which improves the performance of organization. The present study has made an attempt to find the level of factors causing QWL and the impact of outcome of QWL in banks. Since the profile of the banks may be associated with the level of outcomes of QWL, the present study has made an attempt to examine it with the help of one way analysis of variance and t-test. The included outcomes of QWL are job satisfaction, job stress, organizational climate, organizational commitment, employees retention behaviour, service quality employees and service productivity of employees. The highly associated determinants of QWL and the significant difference among the PUSBs and PRSBs have been noticed. The significantly associating important profiles of the banks regarding the existence of outcome of QWL are identified.

Sign in / Sign up

Export Citation Format

Share Document