scholarly journals A biomechanical model to assess the injury risk of leopards (Panthera pardus) hunting by free falling from trees

2021 ◽  
Vol 66 (3) ◽  
Author(s):  
Rudemar Ernesto Blanco ◽  
Daniel Eduardo Luzardo-Vera
Keyword(s):  
Injury Risk ◽  
Biomechanical Model ◽  
Biomechanical Analysis ◽  
Panthera Pardus ◽  
Hunting Behavior ◽  
Severe Injuries ◽  
Video Recordings ◽  
Degree Of Risk ◽  
Free Falling

Leopards have been observed to ambush prey by jumping down on it from trees. There are both anecdotal reports and video recordings of this hunting behavior. Here we conducted a biomechanical analysis of this technique to assess the degree of risk for the predator in such cases. We concluded that the risk of suffering severe injuries seems to be too high for this technique to be a usual way of predation on horned mammals such as male impalas. Our results can be useful in discussing proposed paleobiological hunting scenarios and living predators’ strategies of managing risks.

QUALITATIVE CHANGES IN RHYTHMIC GYMNASTICS HOOP THROWS FROM THE PERSPECTIVE OF BIOMECHANICAL ANALYSIS

2020 ◽  
pp. 1-8
Author(s):  
Raluca Tanasa
Keyword(s):  
Correlation Coefficient ◽  
Video Recording ◽  
Biomechanical Analysis ◽  
Fundamental Groups ◽  
Horizontal Distance ◽  
Video Recordings ◽  
Rhythmic Gymnastics ◽  
Female Gymnasts ◽  
Execution Technique ◽  
Qualitative Changes

Throws and catches in rhythmic gymnastics represent one of the fundamental groups of apparatus actuation. They represent for the hoop actions of great showmanship, but also elements of risk. The purpose of this paper is to improve the throw execution technique through biomechanical analysis in order to increase the performance of female gymnasts in competitions. The subjects of this study were 8 gymnasts aged 9-10 years old, practiced performance Rhythmic Gymnastics. The experiment consisted in video recording and the biomechanical analysis of the element “Hoop throw, step jump and catch”. After processing the video recordings using the Simi Motion software, we have calculated and obtained values concerning: launch height, horizontal distance and throwing angle between the arm and the horizontal. Pursuant to the data obtained, we have designed a series of means to improve the execution technique for the elements comprised within the research and we have implemented them in the training process. Regarding the interpretation of the results, it may be highlighted as follows: height and horizontal distance in this element have values of the correlation coefficient of 0.438 and 0.323, thus a mean significance of 0.005. The values of the arm/horizontal angle have improved for all the gymnasts, the correlation coefficient being 0.931, with a significance of 0.01. As a general conclusion, after the results obtained, it may be stated that the means introduced in the experiment have proven their efficacy, which has led to the optimisation of the execution technique, thus confirming the research hypothesis.

scholarly journals A Narrative Review of Injury Incidence, Location, and Injury Factor of Elite Athletes in Snowsport Events

2021 ◽  
Vol 11 ◽  
Author(s):  
Yongxin Xu ◽  
Chenhao Yang ◽  
Yang Yang ◽  
Xini Zhang ◽  
Shen Zhang ◽  
...  
Keyword(s):  
Injury Risk ◽  
Elite Athletes ◽  
Tendon Injury ◽  
Narrative Review ◽  
Ligament Injury ◽  
Injury Incidence ◽  
Body Parts ◽  
Severe Injuries ◽  
Effective Prevention ◽  
Injury Data

Snowsport athletes face a high injury risk both during training and in competitions. Reducing injury incidence is crucial for athletes to achieve breakthroughs. This narrative review aimed to summarize and analyze injury data of elite athletes in snowsports and provide references for injury prevention and health security for these athletes and their coaches. A total of 39 studies that investigated snowsport injury were analyzed in the present study. On the basis of injury data of elite athletes in snowsports events, this narrative review focused on four aspects, namely, injury incidence, severity, location and causes. The findings of this review were as follows. (1) The highest injury incidence was recorded in freestyle skiing, followed by alpine skiing and snowboarding, the majority of which were moderate and severe injuries. (2) The proportion of injury in competitions and during training was similar. However, more injuries occurred in official training during the Winter Olympic Games; by contrast, injury proportion was higher in competitions during World Cup/World Championships. (3) The most commonly and severely injured body parts were the knees (29.9%), head and face (12.1%), shoulders and clavicula (10.5%), and lower back (8.9%). The most common injury types were joint and ligament injury (41.5%), fracture and bone stress (24.4%), concussion (11.1%), and muscle/tendon injury (10.7%). (4) The main causes of snowsport injury were collisions, falls, and non-contact injuries. Snowsport injury was also influenced by the skill level of the athletes, gender, course setup and equipment. Future studies should further explore the influence of event characteristics and intrinsic and extrinsic risk factors on snowsport injury. An injury or trauma reconstruction may be developed to predict athletic injuries and provide effective prevention strategies.

scholarly journals Finite element and biomechanical analysis of risk factors for implant failure during tension band plating

2020 ◽  
Vol 48 (11) ◽  
pp. 030006052097207
Author(s):  
Jing Ding ◽  
Fei Wang ◽  
Fangchun Jin ◽  
Zhen-kai Wu ◽  
Pin-quan Shen
Keyword(s):  
Residual Stress ◽  
Finite Element ◽  
Finite Element Model ◽  
Three Dimensional ◽  
Biomechanical Model ◽  
Element Model ◽  
Tension Band ◽  
Biomechanical Analysis ◽  
Implant Failure ◽  
Element Analysis

Objective Tension band plating has recently gained widespread acceptance as a method of correcting angular limb deformities in skeletally immature patients. We examined the role of biomechanics in procedural failure and devised a new method of reducing the rate of implant failure. Methods In the biomechanical model, afterload (static or cyclic) was applied to each specimen. The residual stress of the screw combined with different screw sizes and configurations were measured and compared by X-ray diffraction. With regard to static load and similar conditions, the stress distribution was analyzed according to a three-dimensional finite element model. Results The residual stress was close to zero in the static tension group, whereas it was very high in the cyclic load group. The residual stress of screws was significantly lower in the convergent group and parallel group than in the divergent group. The finite element model showed similar results. Conclusions In both the finite element analysis and biomechanical tests, the maximum stress of the screw was concentrated at the position where the screws enter the cortex. Cyclic loading is the primary cause of implant failure.

scholarly journals Biomechanical analysis of indicators of movements in the joints of the lower extremity in patients with coxarthrosis as a method of functional diagnosis

2011 ◽  
Vol 4 (1) ◽  
pp. 94-100
Author(s):  
Vladimir Vasilyevich Guriev ◽  
Vasily Iosifovich Zorya ◽  
Elena Vladimirovna Biryukova ◽  
Roman Alexandrovich Prokopenko ◽  
Alexander Alekseevich Frolov
Keyword(s):  
Joint Stiffness ◽  
Biomechanical Model ◽  
Biomechanical Analysis ◽  
Electromagnetic System ◽  
Joint Injury ◽  
Joint Flexibility ◽  
Functional Diagnosis ◽  
Angular Velocities ◽  
Biomechanical Parameters ◽  
Intact Limb

Biomechanical parameters of the movements of patients with different stages of idiopathic, posttraumatic coxarthrosis and with avascular necrosis were studied. Low limb movements were recorded with electromagnetic system. Angular amplitudes, angular velocities and parameters of joint stiffness and joint flexibility were calculated using movement recordings and previously developed biomechanical model. It was shown that these parameters adequately describe the stage of hip joint injury. As for patients with early stages of coxarthrosis, these parameters describe the differences between the limb under suspicion and the intact limb. The proposed biomechanical parameters can be used as the numerical assessments of a functional state of the low limb under coxarthrosis: for a diagnostics, including early one, for an assessment of the results of operative interventions, for an assessment of the effectiveness of rehabilitation procedures

scholarly journals Reliability and Validity of a Novel Muscle Contusion Device

2009 ◽  
Vol 44 (3) ◽  
pp. 275-278 ◽  
Author(s):  
Nicole M. McBrier ◽  
Thomas Neuberger ◽  
Nori Okita ◽  
Andrew Webb ◽  
Neil Sharkey
Keyword(s):  
Muscle Injury ◽  
Injury Severity ◽  
Peak Load ◽  
Reliability And Validity ◽  
Severe Injuries ◽  
Peak Displacement ◽  
Male Wistar Rats ◽  
Multiple Levels ◽  
Load Peak ◽  
Free Falling

Abstract Context: Many models have been employed to replicate skeletal muscle injury associated with trauma; however, most are restricted to 1 level of severity. Objective: To create and validate an injury-producing device that could generate multiple levels of injury severity. Design: Validation study. Patients or Other Participants: Twenty-six male Wistar rats, 3 to 4 months old. Intervention(s): A contusion device was developed and its ability to deliver consistent impacts was validated alone and in the presence of an experimental animal. A free-falling mass (267 g) was adjusted to the desired height (40, 50, 60, or 70 cm) and then dropped. Main Outcome Measure(s): Peak load, peak displacement, impulse, energy, and velocity peak were measured. Injury severity was determined using magnetic resonance imaging. Results: Outcome measures observed from the device alone were different by height (F18,136  =  21.807, P < .001, 1−β  =  1.0). Outcomes using the experimental animals were also dependent on height (F14,102  =  68.679, P < .001, 1−β  =  1.0). Linear regression analyses indicated that height accounted for 17% to 89% of the variance. Conclusions: Mild to moderate and moderate to severe injuries can be replicated with this device, which will be useful in evaluating clinical treatments on acute muscle injury.

scholarly journals Injury surveillance in taekwondo and judo during physiotherapy coverage of the seventh all Africa Games

2001 ◽  
Vol 57 (1) ◽  
pp. 32-34 ◽  
Author(s):  
J. S. Phillips ◽  
J. M. Frantz ◽  
S. L. Amosun ◽  
W. Weitz
Keyword(s):  
Early Diagnosis ◽  
Injury Prevention ◽  
Risk Ratio ◽  
Medical Staff ◽  
Injury Risk ◽  
Injury Severity ◽  
Upper Limbs ◽  
Severe Injuries ◽  
High Incidence ◽  
Type Of Injury

Objective: To obtain data relating to the incidence of injuries sustained during taekwondo and judo competitions at the 7th All Africa Games.Methods: Prospective recording of injuries sustained by athletes who sought physiotherapy services at the games. Details of type of injury, injury sites and injury severity were obtained.Results: Seventy athletes out of 390 participants reported injuries. The overall injury risk ratio was 0.18. Injuries reported were strains/sprains (65,6%), bruises/contusions (16.1%) and dislocations or fractures (12,9%). The upper limbs were more commonly injured. Of the injuries sustained, approximately 18%, 69% and 13% were respectively classified as mild, moderate and severe injuries.Conclusions: The high incidence of moderate to severe injuries highlights the need for injury prevention programs and the presence of medical staff at major tournaments in order to make early diagnosis and appropriate intervention.

THORAX INJURY CRITERIA ASSESSMENT THROUGH NON-LETHAL IMPACT USING AN ENHANCED BIOMECHANICAL MODEL

2017 ◽  
Vol 17 (07) ◽  
pp. 1740027 ◽  
Author(s):  
MICHÈLE BODO ◽  
ANTHONY BRACQ ◽  
REMI DELILLE ◽  
CHRISTOPHE MARECHAL ◽  
SÉBASTIEN ROTH
Keyword(s):  
Lung Injury ◽  
Injury Risk ◽  
Soft Tissues ◽  
Biomechanical Model ◽  
Local Stress ◽  
The Body ◽  
Constitutive Law ◽  
Maximum Pressure ◽  
Fe Model ◽  
Injury Criteria

Ballistic injury refers to the interaction of a projectile and the human body, resulting in penetration or blunt trauma. In order to consider both consequences, a hydrodynamic elastoplastic constitutive law was implemented in a numerical FE model of the human torso to simulate soft tissues behavior and to evaluate their injury risk. This law, derived from 20% ballistic gelatin, was proven to be very efficient and biofidelic for penetrating ballistic simulation in soft tissues at very high velocity. In this study, the ability of the hydrodynamic law to simulate blunt ballistic trauma is evaluated by the replication of Bir et al.’s (2004) experiments, which is a reference test of the literature for nonpenetrating ballistic impact. Lung injury criteria were also investigated through the Bir et al.’s experiments numerical replication. Human responses were evaluated in terms of mechanical parameters, which can be global (acceleration of the body, viscous criteria and impact force) or local (stress, pressure and displacement). Output results were found to be in experimental corridors developed by Bir et al., and the maximum pressure combined with the duration of the peak of pressure in the lungs seems to be a good predictor for lung injury.

Tackler and ball-carrier technique during moderate and severe injuries (≥8 days lost) compared with player-matched and team-matched injury-free controls in Elite Rugby Union

2021 ◽  
pp. bjsports-2020-103759
Author(s):  
Vincent Meintjes ◽  
Pip Forshaw ◽  
Steve den Hollander ◽  
Lindsay Starling ◽  
Michael Ian Lambert ◽  
...  
Keyword(s):  
Injury Prevention ◽  
Video Analysis ◽  
Effect Size ◽  
Injury Risk ◽  
Rugby Union ◽  
Prevention Strategies ◽  
Severe Injuries ◽  
Technical Proficiency ◽  
Proficiency Scores

ObjectiveTo analyse tackler and ball-carrier technical proficiency during moderate and severe contact injuries (≥8 days lost) in professional rugby union, and compare it with injury-free event-matched controls from the same player and from the same team.MethodsTechnical proficiency for 74 (n=74) (moderate and severe; ≥8 days lost) tackler and ball-carrier injuries during The Currie Cup (2014–2018) and 623 matched non-injury events (253 own controls, 370 team controls) were examined through video analysis using a standardised list of technical criteria.ResultsMean technical proficiency score for injured tacklers during front-on tackles was 6.19/16 (arbitrary units (AU) 95% CI 4.89 to 7.48), which was significantly different to their own controls (8.90/16 AU, 95% CI 8.37 to 9.43, p<0.001, effect size (ES)=1.21, large) and team controls (9.93/16 AU, 95% CI 9.50 to 10.40, p<0.001, ES=1.71, large). Mean technical proficiency score for injured ball-carriers during front-on tackles was 5.60/14 AU (95% CI 4.65 to 6.55), which was significantly different to their own controls (8.08/14 AU, 95% CI 7.56 to 8.60, p<0.001, ES=1.16, moderate) and team controls (8.16/14 AU, 95% CI 7.75 to 8.57, p<0.001, ES=1.25, large).ConclusionFor the tackler and ball-carrier, for both front-on and side-on/behind tackles, overall technical proficiency scores were significantly lower for the injury-causing event, when compared with the player’s own injury-free tackles and the team’s injury-free tackles. Through analysing player and team controls, player technique deficiencies for the injured player and player technique deficiencies that expose all players to injury were highlighted, which may inform injury prevention strategies and policies, and assist coaches in optimising training to reduce tackle injury risk.

Single- Versus Dual-Task Functional Movement Paradigms: A Biomechanical Analysis

2020 ◽  
pp. 1-12
Author(s):  
Landon B. Lempke ◽  
Jeonghoon Oh ◽  
Rachel S. Johnson ◽  
Julianne D. Schmidt ◽  
Robert C. Lynall
Keyword(s):  
Dual Task ◽  
Ground Reaction Force ◽  
Injury Risk ◽  
Reaction Force ◽  
Mean Difference ◽  
Biomechanical Analysis ◽  
Vertical Ground Reaction Force ◽  
Functional Movement ◽  
Single Task ◽  
Vertical Ground

Context: Laboratory-based movement assessments are commonly performed without cognitive stimuli (ie, single-task) despite the simultaneous cognitive processing and movement (ie, dual task) demands required during sport. Cognitive loading may critically alter human movement and be an important consideration for truly assessing functional movement and understanding injury risk in the laboratory, but limited investigations exist. Objective: To comprehensively examine and compare kinematics and kinetics between single- and dual-task functional movement among healthy participants while controlling for sex. Design: Cross-sectional study. Setting: Laboratory. Patients (or Other Participants): Forty-one healthy, physically active participants (49% female; 22.5 ± 2.1 y; 172.5 ± 11.9 cm; 71.0 ± 13.7 kg) enrolled in and completed the study. Intervention(s): All participants completed the functional movement protocol under single- and dual-task (subtracting by 6s or 7s) conditions in a randomized order. Participants jumped forward from a 30-cm tall box and performed (1) maximum vertical jump landings and (2) dominant and (3) nondominant leg, single-leg 45° cuts after landing. Main Outcome Measures: The authors used mixed-model analysis of variances (α = .05) to compare peak hip, knee, and ankle joint angles (degrees) and moments (N·m/BW) in the sagittal and frontal planes, and peak vertical ground reaction force (N/BW) and vertical impulse (Ns/BW) between cognitive conditions and sex. Results: Dual-task resulted in greater peak vertical ground reaction force compared with single-task during jump landing (mean difference = 0.06 N/BW; 95% confidence interval [CI], 0.01 to 0.12; P = .025) but less force during dominant leg cutting (mean difference = −0.08 N/BW; 95% CI, −0.14 to −0.02; P = .015). Less hip-flexion torque occurred during dual task than single task (mean difference = −0.09 N/BW; 95% CI, −0.17 to −0.02). No other outcomes were different between single and dual task (P ≥ .053). Conclusions: Slight, but potentially important, kinematic and kinetic differences were observed between single- and dual-task that may have implications for functional movement assessments and injury risk research. More research examining how various cognitive and movement tasks interact to alter functional movement among pathological populations is warranted before clinical implementation.

A Biomechanical Analysis of the Plantar Surface of Soccer Shoes

1993 ◽  
Vol 207 (2) ◽  
pp. 93-101 ◽  
Author(s):  
F Majid ◽  
D L Bader
Keyword(s):  
Pressure Distribution ◽  
Experimental System ◽  
Axial Rotation ◽  
Biomechanical Analysis ◽  
Support Surface ◽  
Severe Injuries ◽  
Vertical Column ◽  
Plantar Surface ◽  
Physical Conditions ◽  
Analysis System

The incidence of severe injuries for soccer players may lead to long-term inactivity or, at worst, retirement from the game. Many of these injuries, particularly those involving the lower leg, can be attributed to adverse physical conditions at the interface between the soccer shoe and the playing support surface. This study investigated the biomechanical characteristics at this interface for a range of proprietary soccer shoes. An experimental system was designed and developed which, via a weighted pendulum arm making contact with a vertical column, provided controlled rotation of the forefoot of the soccer shoe on samples of playing surfaces. The overall rotation was found to depend on several physical and material factors. For example, the size 7 soccer shoes produced a statistically significant increase in axial rotation for the same impact energy compared to the larger sized shoes under test. In addition, flat soled shoes, designed for synthetic playing surfaces, produced consistently smaller rotations than shoes with either moulded or screw-in studs, although this finding depended on the moisture content of the playing surface. The pressure distribution within several soccer shoes was also measured using the F-Scan Gait Analysis System, for a subject walking across a grass surface. Results indicated differences in pressure distribution over the first metatarsal area of the foot, in existing shoe designs.

Sign in / Sign up

Export Citation Format

Share Document