scholarly journals Biomechanical Analysis of Serious Neck Injuries Resulting from Judo

Healthcare ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 214
Author(s):  
Tomoyuki Nakanishi ◽  
Masahito Hitosugi ◽  
Haruo Murayama ◽  
Arisa Takeda ◽  
Yasuki Motozawa ◽  
...  
Keyword(s):  
High Speed ◽  
Digital Camera ◽  
The Body ◽  
Neck Injury ◽  
Biomechanical Analysis ◽  
Neck Injuries ◽  
Test Device ◽  
Abbreviated Injury Scale ◽  
Kinematic Data ◽  
Load Cells

To establish a basis for initial diagnosis and for proposing preventive measures for the serious neck injuries occasionally experienced by judo practitioners, the biomechanical mechanisms of these injuries were analyzed. Two male judo experts repeatedly threw an anthropomorphic test device (POLAR dummy) using three throwing techniques (Seoi-nage, Osoto-gari, and Ouchi-gari). The dummy’s kinematic data were captured using a high-speed digital camera, and the load and moment of the neck were measured with load cells. The neck injury criterion (Nij) and beam criterion were also calculated. In Seoi-nage, the anterior and parietal regions of the dummy’s head contacted the tatami (judo mat). Subsequently, most of the body weight was applied, with the neck experiencing the highest compression. However, in Osoto-gari and Ouchi-gari, the occipital region of the dummy’s head contacted the tatami. Significantly higher values of both Nij (median 0.68) and beam criterion (median 0.90) corresponding to a 34.7% to 37.1% risk of neck injury with an abbreviated injury scale score ≥2 were shown in Seoi-nage than in either Ouchi-gari or Osoto-gari. In judo, when thrown by the Seoi-nage technique, serious neck injuries can occur as a result of neck compression that occurs when the head contacts the ground.

Biomechanical Analysis of Soft Tissue Neck Injury During Pedestrian Fall

2002 ◽  
Author(s):  
Anthony Sances ◽  
Srirangam Kumaresan
Keyword(s):  
Cervical Spine ◽  
Soft Tissue ◽  
Direct Contact ◽  
Neck Injury ◽  
Biomechanical Analysis ◽  
Test Device ◽  
Soft Tissue Neck ◽  
Direct Loading ◽  
Inertial Loading ◽  
Serious Injuries

Pedestrians sustain serious injuries when impacted by vehicles [1]. Various biomechanical studies have focused on pedestrian injuries due to direct contact with the vehicle and environment [1–5]. Similar studies on the injuries to the pedestrian due to indirect force such as inertial load are limited [6]. One of the most susceptible regions of the human body to inertial loading is the neck component (cervical spine). The cervical spine connects the head and upper torso, and provides mobility to the head. Direct loading to the head and/or upper torso subjects the cervical spine to indirect loading. For example, in a pedestrian lateral fall on the shoulder, the cervical spine flexes laterally due to inertial loading from the head and upper torso, and may injure its soft tissue components. The purpose of this study is to delineate the biomechanics of the soft tissue neck injury during the pedestrian lateral fall due to vehicular impact using the anthropometric test device.

Analysis of Stand-Up Forklift Operator Injuries in Off-the-Dock and Tip-Over Incidents With a Latched Door on the Operator Access Opening

2016 ◽  
Vol 2 (2) ◽  
Author(s):  
John F. Wiechel ◽  
William R. “Mike” Scott
Keyword(s):  
Head Injury ◽  
High Risk ◽  
High Speed ◽  
Neck Injury ◽  
Thoracic Injury ◽  
Shoulder Injury ◽  
Test Device ◽  
Impact Tests ◽  
Hybrid Iii ◽  
The Impact

A series of tip-over and off-the-dock impact tests were performed with stand-up forklifts to investigate the potential for injury to the operator of a forklift in these types of accidents, when the forklift is equipped with an operator’s compartment door. One Crown Equipment Company 35RRTT Model and one 35RCTT Model stand-up forklifts were used in the impact tests. The only modification to the forklifts for the tests was the placement of a door on the entrance to the operator’s compartment. A Hybrid III anthropomorphic test device (ATD) was placed in the operator’s compartment as a human surrogate. During each test, head accelerations, chest accelerations, neck loads, and lumbar loads were measured on the ATD. The motion of the forklift and the ATD were filmed with real-time video and high-speed cameras. Results from the impact tests indicate that there is a high risk of head injury in a right-side tip-over accident and a high risk of head injury and neck injury in a left-side tip-over accident. There is a high risk of a head injury, neck injury, and thoracic injury in off-the-dock forks-trailing accidents. In an off-the-dock forks-leading accident, there is a high risk of arm/shoulder injury, head injury, and neck injury. In both tip-over and off-the-dock forks-trailing accidents, there is a high probability of an entrapment injury under the overhead guard on the forklift.

scholarly journals Tuna locomotion: a computational hydrodynamic analysis of finlet function

2020 ◽  
Vol 17 (165) ◽  
pp. 20190590 ◽  
Author(s):  
Junshi Wang ◽  
Dylan K. Wainwright ◽  
Royce E. Lindengren ◽  
George V. Lauder ◽  
Haibo Dong
Keyword(s):  
High Speed ◽  
Cross Flow ◽  
The Body ◽  
Hydrodynamic Performance ◽  
Thunnus Albacares ◽  
Hydrodynamic Analysis ◽  
Kinematic Data ◽  
Hydrodynamic Function ◽  
Scombrid Fishes

Finlets are a series of small non-retractable fins common to scombrid fishes (mackerels, bonitos and tunas), which are known for their high swimming speed. It is hypothesized that these small fins could potentially affect propulsive performance. Here, we combine experimental and computational approaches to investigate the hydrodynamics of finlets in yellowfin tuna ( Thunnus albacares ) during steady swimming. High-speed videos were obtained to provide kinematic data on the in vivo motion of finlets. High-fidelity simulations were then carried out to examine the hydrodynamic performance and vortex dynamics of a biologically realistic multiple-finlet model with reconstructed kinematics. It was found that finlets undergo both heaving and pitching motion and are delayed in phase from anterior to posterior along the body. Simulation results show that finlets were drag producing and did not produce thrust. The interactions among finlets helped reduce total finlet drag by 21.5%. Pitching motions of finlets helped reduce the power consumed by finlets during swimming by 20.8% compared with non-pitching finlets. Moreover, the pitching finlets created constructive forces to facilitate posterior body flapping. Wake dynamics analysis revealed a unique vortex tube matrix structure and cross-flow streams redirected by the pitching finlets, which supports their hydrodynamic function in scombrid fishes. Limitations on modelling and the generality of results are also discussed.

The Effect of an Operator Compartment Door on Standup Forklift Off-Dock and Tip-Over Injuries

2013 ◽  
Author(s):  
John F. Wiechel ◽  
William R. (Mike) Scott
Keyword(s):  
Head Injury ◽  
High Risk ◽  
High Speed ◽  
Neck Injury ◽  
Thoracic Injury ◽  
Shoulder Injury ◽  
Test Device ◽  
Impact Tests ◽  
Hybrid Iii ◽  
The Impact

A series of tip-over and off-the-dock impact tests were performed with stand-up forklifts in order to investigate the potential for injury to the operator of a forklift in these types of accidents when the forklift is equipped with an operator’s compartment door. One Crown Equipment Company RR Model and one RC Model stand-up forklift were used in the impact tests. The only modification to the forklifts for the tests was the placement of a door on the entrance to the operator’s compartment. A Hybrid III anthropomorphic test device (ATD) was placed in the operator’s compartment as a human surrogate. During each test, head accelerations, chest accelerations, neck loads and lumbar loads were measured on the ATD. The motion of the forklift and the ATD were filmed with video and high-speed cameras. Results from the impact tests indicate that there is a high risk of head injury in a right side tip-over accident and a high risk of head injury and neck injury in a left side tip-over accident. There is a high risk of a head injury, neck injury and thoracic injury in off-the-dock forks-trailing accidents. In an off-the-dock forks-leading accident there is a high risk of arm/shoulder injury, head injury, and neck injury. In both tip-over and off-the-dock forks-trailing accidents there is a high probability of an entrapment injury under the overhead guard on the forklift.

scholarly journals Lower Neck Injury Assessment Risk Curves Based on Matched-Pair Human Data for Anthropomorphic Test Devices

2021 ◽  
Vol 186 (Supplement_1) ◽  
pp. 639-644
Author(s):  
John Humm ◽  
Narayan Yoganandan
Keyword(s):  
Neck Injury ◽  
Matched Pair ◽  
Test Device ◽  
Abbreviated Injury Scale ◽  
Hybrid Iii ◽  
Force Moment ◽  
Injury Assessment ◽  
Lower Neck ◽  
Injury Outcomes ◽  
Risk Curves

ABSTRACT Introduction Under G +x accelerative loading, the Hybrid III anthropomorphic test device (ATD) is used to advance human safety. Although injury assessment risk curves (IARCs) are available at the level of the occipital condyles (commonly termed as upper neck), they do not exist for the cervical-thoracic junction (lower neck). The objectives of this study are to develop IARCs under G +x impact accelerations for the Hybrid III ATD and test device for human occupant restraint (THOR) ATD at the cervical thoracic junction. Methods A series of Hybrid III ATD tests were conducted using input conditions that matched previously published cadaver tests. A separate series of THOR-ATD tests were conducted using the same input conditions that matched the same previously published cadaver tests. This type of experimental design where the cadaver input condition is the same as the ATD tests are termed matched-pair tests (Cadaver-Hybrid III and Cadaver-THOR-ATD). Injury outcomes from human cadaver tests were used with loads at the cervical thoracic junction, measured in the ATD tests. Data were censored based on injury outcomes and the number of tests conducted on each specimen. Parametric survival analysis was used to derive IARCs for cervical thoracic junction force-, moment-, and interaction-based lower neck injury criterion (LNic). Results Injuries were scored according to the Abbreviated Injury Scale scheme. Abbreviated Injury Scale 1 or 2 was scored as injured. The 50% risk levels for the Hybrid III ATD were 315 N, 70 Nm, and 1.12 for the cervical thoracic A/P shear force-, sagittal plane extension moment-, and LNic-based injury criterion, respectively. Results for the THOR ATD were 261 N, 69 Nm, and 1.51. Conclusions This is the first study to develop cervical thoracic junction IARCs for the ATDs based on force, moment, and LNic for posterior to anterior loading.

Inertial Neck Injuries in Children Involved in Frontal Collisions: Sled Testing Using the 6-Year-Old ATD

2007 ◽  
Author(s):  
Tara L. A. Moore ◽  
Michael T. Prange ◽  
William N. Newberry ◽  
Daniel Peterson ◽  
Brian Smyth ◽  
...  
Keyword(s):  
Head Injury ◽  
Neck Injury ◽  
Crash Severity ◽  
Neck Flexion ◽  
Neck Injuries ◽  
Test Device ◽  
Frontal Crash ◽  
Injury Criteria ◽  
Head Injury Criteria ◽  
Frontal Collisions

Sled tests were conducted using a 6-year-old anthropomorphic test device (ATD) to investigate the effect of restraint type and crash severity on the risk of pediatric inertial neck injury. Tests were conducted at three severities, using three restraint configurations: properly restrained, misused restraint, and an age-inappropriate restraint. ATD injury measurements increased with increased crash severity. Head accelerations, head injury criteria, and neck loads, with the exception of neck flexion, were relatively independent of restraint configuration at a given crash severity. The data show that children are at risk of inertial neck injuries at high frontal crash severities.

Biomechanical Analysis of the Preparatory Motion for Takeoff in the Fosbury Flop

1986 ◽  
Vol 2 (2) ◽  
pp. 66-77 ◽  
Author(s):  
Michiyoshi Ae ◽  
Yukinori Sakatani ◽  
Takashi Yokoi ◽  
Yoshihiro Hashihara ◽  
Kanji Shibukawa
Keyword(s):  
High Speed ◽  
Center Of Gravity ◽  
The Body ◽  
Biomechanical Analysis ◽  
Major Purpose ◽  
3 Dimensional ◽  
Preparatory Phase ◽  
Approach Velocity

The major purpose of this study was to investigate the preparatory motion during the last stride executed by Fosbury-flop jumpers, using 3-dimensional cinematography. Most of the trials for five male high jumpers were filmed at an official track meet by two high-speed cameras. The results suggested that to lower the center of gravity during the preparatory phase, Fosbury-flop jumpers using a curved approach ran resorted to (a) leaning the body toward the center of the curve, and (b) flexing the body. Two types of preparatory motion were classified, and their characteristics were identified concerning the loss of approach velocity and a large and effective takeoff motion.

scholarly journals Kinematics of feeding in the lizard Agama stellio

1996 ◽  
Vol 199 (8) ◽  
pp. 1727-1742 ◽  
Author(s):  
A Herrel ◽  
J Cleuren ◽  
F Vree
Keyword(s):  
High Speed ◽  
Prey Capture ◽  
Prey Type ◽  
The Body ◽  
Kinematic Data ◽  
Video Recordings ◽  
Lower Jaw ◽  
Feeding Cycle ◽  
Hyolingual Apparatus ◽  
Opening Phase

The kinematics of prey capture, intraoral transport and swallowing in lizards of the species Agama stellio (Agamidae) were investigated using cineradiography (50 frames s-1) and high-speed video recordings (500 frames s-1). Small metal markers were inserted into different parts of the upper and lower jaw and the tongue. Video and cineradiographic images were digitized, and displacements of the body, head, upper and lower jaw and the tongue were quantified. Twenty additional variables depicting displacements and timing of events were calculated. A factor analysis performed on the kinematic data separates prey capture and swallowing cycles from intraoral transport bites. However, the intraoral transport stage cannot be separated into chewing (reduction) and transport bites. The effect of prey type and size on the feeding kinematics of intraoral transport and swallowing cycles was investigated. During the intraoral transport stage, distinct aspects (e.g. durations, maximal excursions) of the gape and tongue cycle are modulated in response to both the size and type of the prey item. The results for A. stellio generally agree with a previous model, although it is the entire slow opening phase rather than solely the duration of the second part of this phase that is affected by the size of the prey. The intraoral transport cycles in A. stellio show the two synapomorphic characteristics of tetrapods (tongue-based terrestrial intraoral prey transport and the existence of a long preparatory period of prey compression). However, not all five characters of the feeding cycle previously proposed for amniotes are present in A. stellio. One major difference is that in A. stellio the recovery of the hyolingual apparatus does not take place during the slow opening phase but during the slow closing/powerstroke phase.

Some Special Aspects of Hypersonic Flow Fields

1959 ◽  
Vol 63 (585) ◽  
pp. 508-512 ◽  
Author(s):  
K. W. Mangler
Keyword(s):  
Hypersonic Flow ◽  
High Speed ◽  
Flow Fields ◽  
The Body ◽  
Lower Velocity ◽  
Bow Wave ◽  
Total Head ◽  
Bow Shocks ◽  
Lower Entropy ◽  
Subsonic Region

When a body moves through air at very high speed at such a height that the air can be considered as a continuum, the distinction between sharp and blunt noses with their attached or detached bow shocks loses its significance, since, in practical cases, the bow wave is always detached and fairly strong. In practice, all bodies behave as blunt shapes with a smaller or larger subsonic region near the nose where the entropy and the corresponding loss of total head change from streamline to streamline due to the curvature of the bow shock. These entropy gradients determine the behaviour of the hypersonic flow fields to a large extent. Even in regions where viscosity effects are small they give rise to gradients of the velocity and shear layers with a lower velocity and a higher entropy near the surface than would occur in their absence. Thus one can expect to gain some relief in the heating problems arising on the surface of the body. On the other hand, one would lose farther downstream on long slender shapes as more and more air of lower entropy is entrained into the boundary layer so that the heat transfer to the surface goes up again. Both these flow regions will be discussed here for the simple case of a body of axial symmetry at zero incidence. Finally, some remarks on the flow field past a lifting body will be made. Recently, a great deal of information on these subjects has appeared in a number of reviewing papers so that little can be added. The numerical results on the subsonic flow regions in Section 2 have not been published before.

scholarly journals Using Different Combinations of Body-Mounted IMU Sensors to Estimate Speed of Horses—A Machine Learning Approach

Sensors ◽  
2021 ◽  
Vol 21 (3) ◽  
pp. 798
Author(s):  
Hamed Darbandi ◽  
Filipe Serra Bragança ◽  
Berend Jan van der Zwaag ◽  
John Voskamp ◽  
Annik Imogen Gmel ◽  
...  
Keyword(s):  
Machine Learning ◽  
The Body ◽  
Biomechanical Analysis ◽  
Estimation Accuracy ◽  
Speed Estimation ◽  
Motion Patterns ◽  
Positioning Systems ◽  
Machine Learning Approach ◽  
Global Positioning ◽  
Measurement Units

Speed is an essential parameter in biomechanical analysis and general locomotion research. It is possible to estimate the speed using global positioning systems (GPS) or inertial measurement units (IMUs). However, GPS requires a consistent signal connection to satellites, and errors accumulate during IMU signals integration. In an attempt to overcome these issues, we have investigated the possibility of estimating the horse speed by developing machine learning (ML) models using the signals from seven body-mounted IMUs. Since motion patterns extracted from IMU signals are different between breeds and gaits, we trained the models based on data from 40 Icelandic and Franches-Montagnes horses during walk, trot, tölt, pace, and canter. In addition, we studied the estimation accuracy between IMU locations on the body (sacrum, withers, head, and limbs). The models were evaluated per gait and were compared between ML algorithms and IMU location. The model yielded the highest estimation accuracy of speed (RMSE = 0.25 m/s) within equine and most of human speed estimation literature. In conclusion, highly accurate horse speed estimation models, independent of IMU(s) location on-body and gait, were developed using ML.

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