Wu, L C; Nangia, V; Bui, K; Hammoor, B; Kurt, M; Hernandez, F; Kuo, C; Camarillo, D B
In Vivo Evaluation of Wearable Head Impact Sensors Journal Article
In: Annals of Biomedical Engineering, vol. 44, no. 4, pp. 1234–1245, 2016.
Abstract | BibTeX | Tags: *Head Movements/ph [Physiology], *Models, *Soccer/ph [Physiology], *Telemetry/is [Instrumentation], adult, Biological, Biomechanical Phenomena, Craniocerebral Trauma, Humans, Male, MOUTH protectors, Skin, Soccer/in [Injuries], VIDEO recording
@article{Wu2016,
title = {In Vivo Evaluation of Wearable Head Impact Sensors},
author = {Wu, L C and Nangia, V and Bui, K and Hammoor, B and Kurt, M and Hernandez, F and Kuo, C and Camarillo, D B},
year = {2016},
date = {2016-01-01},
journal = {Annals of Biomedical Engineering},
volume = {44},
number = {4},
pages = {1234--1245},
abstract = {Inertial sensors are commonly used to measure human head motion. Some sensors have been tested with dummy or cadaver experiments with mixed results, and methods to evaluate sensors in vivo are lacking. Here we present an in vivo method using high speed video to test teeth-mounted (mouthguard), soft tissue-mounted (skin patch), and headgear-mounted (skull cap) sensors during 6-13 g sagittal soccer head impacts. Sensor coupling to the skull was quantified by displacement from an ear-canal reference. Mouthguard displacements were within video measurement error (\<1 mm), while the skin patch and skull cap displaced up to 4 and 13 mm from the ear-canal reference, respectively. We used the mouthguard, which had the least displacement from skull, as the reference to assess 6-degree-of-freedom skin patch and skull cap measurements. Linear and rotational acceleration magnitudes were over-predicted by both the skin patch (with 120% NRMS error for a(mag), 290% for alpha(mag)) and the skull cap (320% NRMS error for a(mag), 500% for alpha(mag)). Such over-predictions were largely due to out-of-plane motion. To model sensor error, we found that in-plane skin patch linear acceleration in the anterior-posterior direction could be modeled by an underdamped viscoelastic system. In summary, the mouthguard showed tighter skull coupling than the other sensor mounting approaches. Furthermore, the in vivo methods presented are valuable for investigating skull acceleration sensor technologies.},
keywords = {*Head Movements/ph [Physiology], *Models, *Soccer/ph [Physiology], *Telemetry/is [Instrumentation], adult, Biological, Biomechanical Phenomena, Craniocerebral Trauma, Humans, Male, MOUTH protectors, Skin, Soccer/in [Injuries], VIDEO recording},
pubstate = {published},
tppubtype = {article}
}
Richards, D; Ivarsson, B J; Scher, I; Hoover, R; Rodowicz, K; Cripton, P
Ice hockey shoulder pad design and the effect on head response during shoulder-to-head impacts Journal Article
In: Sports Biomechanics, vol. 15, no. 4, pp. 385–396, 2016.
Abstract | BibTeX | Tags: *Craniocerebral Trauma/pc [Prevention & Control], *Head/ph [Physiology], *Hockey/ph [Physiology], *Protective Clothing, *Shoulder/ph [Physiology], Acceleration, Biomechanical Phenomena, Equipment Design, Humans, Male, Manikins, Materials testing, Reproducibility of Results, Risk Factors
@article{Richards2016,
title = {Ice hockey shoulder pad design and the effect on head response during shoulder-to-head impacts},
author = {Richards, D and Ivarsson, B J and Scher, I and Hoover, R and Rodowicz, K and Cripton, P},
year = {2016},
date = {2016-01-01},
journal = {Sports Biomechanics},
volume = {15},
number = {4},
pages = {385--396},
abstract = {Ice hockey body checks involving direct shoulder-to-head contact frequently result in head injury. In the current study, we examined the effect of shoulder pad style on the likelihood of head injury from a shoulder-to-head check. Shoulder-to-head body checks were simulated by swinging a modified Hybrid-III anthropomorphic test device (ATD) with and without shoulder pads into a stationary Hybrid-III ATD at 21 km/h. Tests were conducted with three different styles of shoulder pads (traditional, integrated and tethered) and without shoulder pads for the purpose of control. Head response kinematics for the stationary ATD were measured. Compared to the case of no shoulder pads, the three different pad styles significantly (p \< 0.05) reduced peak resultant linear head accelerations of the stationary ATD by 35-56%. The integrated shoulder pads reduced linear head accelerations by an additional 18-21% beyond the other two styles of shoulder pads. The data presented here suggest that shoulder pads can be designed to help protect the head of the struck player in a shoulder-to-head check.},
keywords = {*Craniocerebral Trauma/pc [Prevention \& Control], *Head/ph [Physiology], *Hockey/ph [Physiology], *Protective Clothing, *Shoulder/ph [Physiology], Acceleration, Biomechanical Phenomena, Equipment Design, Humans, Male, Manikins, Materials testing, Reproducibility of Results, Risk Factors},
pubstate = {published},
tppubtype = {article}
}
Williams, R M; Dowling, M; O'Connor, K L
Head Impact Measurement Devices Journal Article
In: Sports & Health, vol. 8, no. 3, pp. 270–273, 2016.
Abstract | BibTeX | Tags: *Accelerometry, *Athletic Injuries/di [Diagnosis], *Brain Concussion/di [Diagnosis], Athletic Injuries/pp [Physiopathology], Biomechanical Phenomena, Brain Concussion/pp [Physiopathology], Head Protective Devices, Head/pp [Physiopathology], Humans
@article{Williams2016b,
title = {Head Impact Measurement Devices},
author = {Williams, R M and Dowling, M and O'Connor, K L},
year = {2016},
date = {2016-01-01},
journal = {Sports \& Health},
volume = {8},
number = {3},
pages = {270--273},
abstract = {CONTEXT: Concussive injuries are at the forefront of sports medicine research. Recently, researchers have used a variety of head- and helmet-based impact-monitoring devices to quantify impacts sustained during contact sport participation. This review provides an up-to-date collection of head accelerometer use at the youth, high school, and collegiate levels. EVIDENCE ACQUISITION: PubMed was searched for articles published between 1980 and 2015 using the terms accelerometer and concussion, impact sensor and concussion, head impact telemetry system, head impact telemetry, and linear acceleration and concussion. An additional Google search was performed to capture devices without publications. STUDY DESIGN: Clinical review. LEVEL OF EVIDENCE: Level 4. RESULTS: Twenty-four products track and/or record head impact for clinical or research use. Ten of these head impact devices have publications supporting their utility. CONCLUSION: Head impact measuring devices can describe athlete exposure in terms of magnitude and/or frequency, highlighting their utility within a multimodal approach for concussion assessment and diagnosis.},
keywords = {*Accelerometry, *Athletic Injuries/di [Diagnosis], *Brain Concussion/di [Diagnosis], Athletic Injuries/pp [Physiopathology], Biomechanical Phenomena, Brain Concussion/pp [Physiopathology], Head Protective Devices, Head/pp [Physiopathology], Humans},
pubstate = {published},
tppubtype = {article}
}
Little, C E; Emery, C; Black, A; Scott, S H; Meeuwisse, W; Nettel-Aguirre, A; Benson, B; Dukelow, S
Test-retest reliability of KINARM robot sensorimotor and cognitive assessment: in pediatric ice hockey players Journal Article
In: Journal of Neuroengineering & Rehabilitation, vol. 12, pp. 78, 2015.
Abstract | BibTeX | Tags: *Brain Concussion/di [Diagnosis], *Brain Concussion/px [Psychology], *COGNITION, *Hockey/in [Injuries], *Robotics, *Sensation, Adolescent, Biomechanical Phenomena, Brain Concussion/pp [Physiopathology], Child, Computer simulation, Humans, learning, Longitudinal studies, Male, Neuropsychological Tests, Practice (Psychology), Prognosis, Prospective Studies, Psychomotor Performance/ph [Physiology], Reproducibility of Results, treatment outcome
@article{Little2015,
title = {Test-retest reliability of KINARM robot sensorimotor and cognitive assessment: in pediatric ice hockey players},
author = {Little, C E and Emery, C and Black, A and Scott, S H and Meeuwisse, W and Nettel-Aguirre, A and Benson, B and Dukelow, S},
year = {2015},
date = {2015-01-01},
journal = {Journal of Neuroengineering \& Rehabilitation},
volume = {12},
pages = {78},
abstract = {BACKGROUND: Better diagnostic and prognostic tools are needed to address issues related to early diagnosis and management of concussion across the continuum of aging but particularly in children and adolescents. The purpose of the current study was to evaluate the reliability of robotic technology (KINARM robot) assessments of reaching, position sense, bimanual motor function, visuospatial skills, attention and decision making in youth ice hockey players (ages 10-14). METHODS: Thirty-four male children attended two testing days, one week apart. On day one, each subject completed five tasks on the robot with two examiners (alternating examiner sequence); the 2(nd) examiner followed the same procedure as the 1(st) immediately afterwards. One consistent examiner tested subjects one week later. This is a test-retest reliability study. The robotic tasks characterize sensorimotor and/or cognitive performance; 63 parameters from 5 tasks are reported. Session 1 was the 1(st) time the subject performed the 5 tasks, session 2 the 2(nd) time on day 1, and session 3 one week following. RESULTS: Intra-class correlation coefficients ranged from 0.06 to 0.91 and 0.09 to 0.90 for session 1 to 2 and 2 to 3, respectively. Bland-Altman plots showed agreement in a majority of the parameters and a learning effect in 25 % and 24 % of parameters in session 1 vs 2 and 1 vs 3, respectively but none for session 2 vs 3. Of those that showed a learning effect, only 8 % of parameters in session 1 vs 2 and 10 % in session 1 vs 3 had a clinical relevance measure\>0.8. CONCLUSIONS: The relative homogeneity of the sample and the effect of learning seen in some of the task parameters appears to have negatively impacted the intra-class correlation coefficients from session 1 to 2, with less impact for 2 to 3. The Bland-Altman analysis supports good absolute reliability in healthy male children with no neurological impairment ranging in age from 10 to 14. The clinically relevant learning effect seen, in a small number of parameters could be addressed by creating a learning effect adjustment factor and/or implementing a practice session, which would eliminate the learning effect.},
keywords = {*Brain Concussion/di [Diagnosis], *Brain Concussion/px [Psychology], *COGNITION, *Hockey/in [Injuries], *Robotics, *Sensation, Adolescent, Biomechanical Phenomena, Brain Concussion/pp [Physiopathology], Child, Computer simulation, Humans, learning, Longitudinal studies, Male, Neuropsychological Tests, Practice (Psychology), Prognosis, Prospective Studies, Psychomotor Performance/ph [Physiology], Reproducibility of Results, treatment outcome},
pubstate = {published},
tppubtype = {article}
}
Lockhart, P A; Cronin, D S
Helmet liner evaluation to mitigate head response from primary blast exposure Journal Article
In: Computer Methods in Biomechanics & Biomedical Engineering, vol. 18, no. 6, pp. 635–645, 2015.
Abstract | BibTeX | Tags: *Blast Injuries/pc [Prevention & Control], *Craniocerebral Trauma/pc [Prevention & Control], *Explosions, *Head Protective Devices, Acceleration, Aluminum/ch [Chemistry], Biomechanical Phenomena, brain concussion, Brain Injuries, Brain/ph [Physiology], Computer simulation, CPD4NFA903 (Aluminum), Equipment Design, Head, Humans, intracranial pressure, Male, Materials testing
@article{Lockhart2015,
title = {Helmet liner evaluation to mitigate head response from primary blast exposure},
author = {Lockhart, P A and Cronin, D S},
year = {2015},
date = {2015-01-01},
journal = {Computer Methods in Biomechanics \& Biomedical Engineering},
volume = {18},
number = {6},
pages = {635--645},
abstract = {Head injury resulting from blast loading, including mild traumatic brain injury, has been identified as an important blast-related injury in modern conflict zones. A study was undertaken to investigate potential protective ballistic helmet liner materials to mitigate primary blast injury using a detailed sagittal plane head finite element model, developed and validated against previous studies of head kinematics resulting from blast exposure. Five measures reflecting the potential for brain injury that were investigated included intracranial pressure, brain tissue strain, head acceleration (linear and rotational) and the head injury criterion. In simulations, these measures provided consistent predictions for typical blast loading scenarios. Considering mitigation, various characteristics of foam material response were investigated and a factor analysis was performed which showed that the four most significant were the interaction effects between modulus and hysteretic response, stress-strain response, damping factor and density. Candidate materials were then identified using the predicted optimal material values. Polymeric foam was found to meet the density and modulus requirements; however, for all significant parameters, higher strength foams, such as aluminum foam, were found to provide the highest reduction in the potential for injury when compared against the unprotected head.},
keywords = {*Blast Injuries/pc [Prevention \& Control], *Craniocerebral Trauma/pc [Prevention \& Control], *Explosions, *Head Protective Devices, Acceleration, Aluminum/ch [Chemistry], Biomechanical Phenomena, brain concussion, Brain Injuries, Brain/ph [Physiology], Computer simulation, CPD4NFA903 (Aluminum), Equipment Design, Head, Humans, intracranial pressure, Male, Materials testing},
pubstate = {published},
tppubtype = {article}
}
Oeur, R A; Karton, C; Post, A; Rousseau, P; Hoshizaki, T B; Marshall, S; Brien, S E; Smith, A; Cusimano, M D; Gilchrist, M D
In: Journal of Neurosurgery, vol. 123, no. 2, pp. 415–422, 2015.
Abstract | Links | BibTeX | Tags: accident, Accident reconstruction, accidental injury, Accidents, Adolescent, adult, Article, Biomechanical Phenomena, Biomechanics, brain, brain concussion, brain stem, brain tissue, Cerebellum, clinical article, comparative study, Concussion, controlled study, Female, finite element analysis, Finite element modelling, gray matter, Hematoma, human, Humans, Hybrid iii headform, injury severity, laboratory test, Male, Mechanical, mechanical stress, middle aged, pathology, Pathophysiology, Persistent postconcussive symptoms, PHYSIOLOGY, Post Hoc Analysis, Post-Concussion Syndrome, postconcussion syndrome, priority journal, shear stress, simulation, SPORTS medicine, STATISTICAL significance, Stress, stress strain relationship, Subdural, subdural hematoma, traumatic brain injury, white matter, Young Adult
@article{Oeur2015,
title = {A comparison of head dynamic response and brain tissue stress and strain using accident reconstructions for concussion, concussion with persistent postconcussive symptoms, and subdural hematoma},
author = {Oeur, R A and Karton, C and Post, A and Rousseau, P and Hoshizaki, T B and Marshall, S and Brien, S E and Smith, A and Cusimano, M D and Gilchrist, M D},
doi = {10.3171/2014.10.JNS14440},
year = {2015},
date = {2015-01-01},
journal = {Journal of Neurosurgery},
volume = {123},
number = {2},
pages = {415--422},
abstract = {Object Concussions typically resolve within several days, but in a few cases the symptoms last for a month or longer and are termed persistent postconcussive symptoms (PPCS). These persisting symptoms may also be associated with more serious brain trauma similar to subdural hematoma (SDH). The objective of this study was to investigate the head dynamic and brain tissue responses of injury reconstructions resulting in concussion, PPCS, and SDH. Methods Reconstruction cases were obtained from sports medicine clinics and hospitals. All subjects received a direct blow to the head resulting in symptoms. Those symptoms that resolved in 9 days or fewer were defined as concussions (n = 3). Those with symptoms lasting longer than 18 months were defined as PPCS (n = 3), and 3 patients presented with SDHs (n = 3). A Hybrid III headform was used in reconstruction to obtain linear and rotational accelerations of the head. These dynamic response data were then input into the University College Dublin Brain Trauma Model to calculate maximum principal strain and von Mises stress. A Kruskal-Wallis test followed by Tukey post hoc tests were used to compare head dynamic and brain tissue responses between injury groups. Statistical significance was set at p \< 0.05. Results A significant difference was identified for peak resultant linear and rotational acceleration between injury groups. Post hoc analyses revealed the SDH group had higher linear and rotational acceleration responses (316 g and 23,181 rad/sec2, respectively) than the concussion group (149 g and 8111 rad/sec2, respectively; p \< 0.05). No significant differences were found between groups for either brain tissue measures of maximum principal strain or von Mises stress. Conclusions The reconstruction of accidents resulting in a concussion with transient symptoms (low severity) and SDHs revealed a positive relationship between an increase in head dynamic response and the risk for more serious brain injury. This type of relationship was not found for brain tissue stress and strain results derived by finite element analysis. Future research should be undertaken using a larger sample size to confirm these initial findings. Understanding the relationship between the head dynamic and brain tissue response and the nature of the injury provides important information for developing strategies for injury prevention. © AANS, 2015.},
keywords = {accident, Accident reconstruction, accidental injury, Accidents, Adolescent, adult, Article, Biomechanical Phenomena, Biomechanics, brain, brain concussion, brain stem, brain tissue, Cerebellum, clinical article, comparative study, Concussion, controlled study, Female, finite element analysis, Finite element modelling, gray matter, Hematoma, human, Humans, Hybrid iii headform, injury severity, laboratory test, Male, Mechanical, mechanical stress, middle aged, pathology, Pathophysiology, Persistent postconcussive symptoms, PHYSIOLOGY, Post Hoc Analysis, Post-Concussion Syndrome, postconcussion syndrome, priority journal, shear stress, simulation, SPORTS medicine, STATISTICAL significance, Stress, stress strain relationship, Subdural, subdural hematoma, traumatic brain injury, white matter, Young Adult},
pubstate = {published},
tppubtype = {article}
}
Hernandez, F; Shull, P B; Camarillo, D B
Evaluation of a laboratory model of human head impact biomechanics Journal Article
In: Journal of Biomechanics, vol. 48, no. 12, pp. 3469–3477, 2015.
Abstract | BibTeX | Tags: *HEAD, *Laboratories, *Mechanical Phenomena, *Models, Acceleration, Biological, Biomechanical Phenomena, Brain Concussion/et [Etiology], Football/in [Injuries], Head Protective Devices, Humans, Male, Neck/ph [Physiology], Rotation, SAFETY
@article{Hernandez2015,
title = {Evaluation of a laboratory model of human head impact biomechanics},
author = {Hernandez, F and Shull, P B and Camarillo, D B},
year = {2015},
date = {2015-01-01},
journal = {Journal of Biomechanics},
volume = {48},
number = {12},
pages = {3469--3477},
abstract = {This work describes methodology for evaluating laboratory models of head impact biomechanics. Using this methodology, we investigated: how closely does twin-wire drop testing model head rotation in American football impacts? Head rotation is believed to cause mild traumatic brain injury (mTBI) but helmet safety standards only model head translations believed to cause severe TBI. It is unknown whether laboratory head impact models in safety standards, like twin-wire drop testing, reproduce six degree-of-freedom (6DOF) head impact biomechanics that may cause mTBI. We compared 6DOF measurements of 421 American football head impacts to twin-wire drop tests at impact sites and velocities weighted to represent typical field exposure. The highest rotational velocities produced by drop testing were the 74th percentile of non-injury field impacts. For a given translational acceleration level, drop testing underestimated field rotational acceleration by 46% and rotational velocity by 72%. Primary rotational acceleration frequencies were much larger in drop tests ($sim$100 Hz) than field impacts ($sim$10 Hz). Drop testing was physically unable to produce acceleration directions common in field impacts. Initial conditions of a single field impact were highly resolved in stereo high-speed video and reconstructed in a drop test. Reconstruction results reflected aggregate trends of lower amplitude rotational velocity and higher frequency rotational acceleration in drop testing, apparently due to twin-wire constraints and the absence of a neck. These results suggest twin-wire drop testing is limited in modeling head rotation during impact, and motivate continued evaluation of head impact models to ensure helmets are tested under conditions that may cause mTBI. Copyright © 2015 Elsevier Ltd. All rights reserved.},
keywords = {*HEAD, *Laboratories, *Mechanical Phenomena, *Models, Acceleration, Biological, Biomechanical Phenomena, Brain Concussion/et [Etiology], Football/in [Injuries], Head Protective Devices, Humans, Male, Neck/ph [Physiology], Rotation, SAFETY},
pubstate = {published},
tppubtype = {article}
}
Kettner, M; Ramsthaler, F; Potente, S; Bockenheimer, A; Schmidt, P H; Schrodt, M
Blunt force impact to the head using a teeball bat: systematic comparison of physical and finite element modeling Journal Article
In: Forensic Science, Medicine & Pathology, vol. 10, no. 4, pp. 513–517, 2014.
Abstract | BibTeX | Tags: *Computer Simulation, *Forensic Pathology/mt [Methods], *HEAD injuries, *Models, *Skull Fractures/pa [Pathology], *Skull/pa [Pathology], *Sports Equipment, *Weapons, Anatomic, Biological, Biomechanical Phenomena, Closed/pa [Pathology], Equipment Design, finite element analysis, Humans, Skull/in [Injuries], violence, Wood, Young Adult
@article{Kettner2014,
title = {Blunt force impact to the head using a teeball bat: systematic comparison of physical and finite element modeling},
author = {Kettner, M and Ramsthaler, F and Potente, S and Bockenheimer, A and Schmidt, P H and Schrodt, M},
year = {2014},
date = {2014-01-01},
journal = {Forensic Science, Medicine \& Pathology},
volume = {10},
number = {4},
pages = {513--517},
abstract = {Blunt head trauma secondary to violent actions with various weapons is frequently a cause of injury in forensic casework; differing striking tools have varying degrees of injury capacity. The systematic approach used to examine a 19-year-old student who was beaten with a wooden teeball bat will be described. The assailant stopped beating the student when the teeball bat broke into two pieces. The surviving victim sustained bruises and a forehead laceration. The State's Attorney assigned a forensic expert to examine whether the forces exerted on the victim's head (leading to the fracture of the bat) were potentially life threatening (e.g. causing cranial bone fractures). Physical modeling was conducted using a pigskin-covered polyethylene end cap cushioned by cellulose that was connected to a piezoelectric force gauge. Experiments with teeball bats weighing 295-485 g demonstrated that 12-20 kN forces were necessary to cause a comparable bat fracture. In addition to physical testing, a computer-aided simulation was conducted, utilizing a finite-element (FE) method. In the FE approach, after selecting for wood properties, a virtual bat was swung against a hemisphere comprising two layers that represented bone and soft tissue. Employing this model, a 17.6 kN force was calculated, with the highest fracture probability points resembling the fracture patterns of the physically tested bats.},
keywords = {*Computer Simulation, *Forensic Pathology/mt [Methods], *HEAD injuries, *Models, *Skull Fractures/pa [Pathology], *Skull/pa [Pathology], *Sports Equipment, *Weapons, Anatomic, Biological, Biomechanical Phenomena, Closed/pa [Pathology], Equipment Design, finite element analysis, Humans, Skull/in [Injuries], violence, Wood, Young Adult},
pubstate = {published},
tppubtype = {article}
}
McIntosh, A S; Lai, A; Schilter, E
Bicycle helmets: head impact dynamics in helmeted and unhelmeted oblique impact tests Journal Article
In: Traffic Injury Prevention, vol. 14, no. 5, pp. 501–508, 2013.
Abstract | BibTeX | Tags: *Accidents, *Bicycling/in [Injuries], *Craniocerebral Trauma/et [Etiology], *Head Protective Devices/ut [Utilization], Acceleration, Biological, Biomechanical Phenomena, Computer simulation, Humans, Male, Manikins, Models, Traffic/sn [Statistics & Numerical Dat
@article{McIntosh2013,
title = {Bicycle helmets: head impact dynamics in helmeted and unhelmeted oblique impact tests},
author = {McIntosh, A S and Lai, A and Schilter, E},
year = {2013},
date = {2013-01-01},
journal = {Traffic Injury Prevention},
volume = {14},
number = {5},
pages = {501--508},
abstract = {OBJECTIVE: To assess the factors, including helmet use, that contribute to head linear and angular acceleration in bicycle crash simulation tests. METHOD: A series of laboratory tests was undertaken using an oblique impact rig. The impact rig included a drop assembly with a Hybrid III head and neck. The head struck a horizontally moving striker plate. Head linear and angular acceleration and striker plate force were measured. The Head Injury Criterion was derived. The following test parameters were varied: drop height to a maximum of 1.5 m, horizontal speed to a maximum of 25 km/h, helmet/no helmet, impact orientation/location, and restraint adjustment. Additional radial impacts were conducted on the same helmet models for comparison purposes. Descriptive statistics were derived and multiple regression was applied to examine the role of each parameter. RESULTS: Helmet use was the most significant factor in reducing the magnitude of all outcome variables. Linear acceleration and the Head Injury Criterion were influenced by the drop height, whereas angular acceleration tended to be influenced by the horizontal speed and impact orientation/location. The restraint adjustment influenced the outcome variables, with lower coefficients of variation observed with the tight restraint. CONCLUSIONS: The study reinforces the benefits of wearing a bicycle helmet in a crash. The study also demonstrates that helmets do not increase angular head acceleration. The study assists in establishing the need for an agreed-upon international oblique helmet test as well as the boundary conditions for oblique helmet testing.},
keywords = {*Accidents, *Bicycling/in [Injuries], *Craniocerebral Trauma/et [Etiology], *Head Protective Devices/ut [Utilization], Acceleration, Biological, Biomechanical Phenomena, Computer simulation, Humans, Male, Manikins, Models, Traffic/sn [Statistics \& Numerical Dat},
pubstate = {published},
tppubtype = {article}
}
Ivancic, P C
Neck injury response to direct head impact Journal Article
In: Accident Analysis & Prevention, vol. 50, pp. 323–329, 2013.
Abstract | BibTeX | Tags: *Accidents, *Neck Injuries/et [Etiology], *Neck Injuries/pp [Physiopathology], Acceleration, ANALYSIS of variance, Biomechanical Phenomena, Cadaver, Humans, Manikins, Rotation, Traffic, VIDEO recording
@article{Ivancic2013,
title = {Neck injury response to direct head impact},
author = {Ivancic, P C},
year = {2013},
date = {2013-01-01},
journal = {Accident Analysis \& Prevention},
volume = {50},
pages = {323--329},
abstract = {Previous in vivo studies have observed flexion of the upper or upper/middle cervical spine and extension at inferior spinal levels due to direct head impacts. These studies hypothesized that hyperflexion may contribute to injury of the upper or middle cervical spine during real-life head impact. Our objectives were to determine the cervical spine injury response to direct head impact, document injuries, and compare our results with previously reported in vivo data. Our model consisted of a human cadaver neck (n=6) mounted to the torso of a rear impact dummy and carrying a surrogate head. Rearward force was applied to the model's forehead using a cable and pulley system and free-falling mass of 3.6kg followed by 16.7kg. High-speed digital cameras tracked head, vertebral, and pelvic motions. Average peak spinal rotations observed during impact were statistically compared (P\<0.05) to physiological ranges obtained from intact flexibility tests. Peak head impact force was 249 and 504N for the 3.6 and 16.7kg free-falling masses, respectively. Occipital condyle loads reached 205.3N posterior shear, 331.4N compression, and 7.4Nm extension moment. We observed significant increases in intervertebral extension peaks above physiologic at C6/7 (26.3degree vs. 5.7degree) and C7/T1 (29.7degree vs. 4.6degree) and macroscopic ligamentous and osseous injuries at C6 through T1 due to the 504N impacts. Our results indicate that a rearward head shear force causes complex neck loads of posterior shear, compression, and extension moment sufficient to injure the lower cervical spine. Real-life neck injuries due to motor vehicle crashes, sports impacts, or falls are likely due to combined loads transferred to the neck by direct head impact and torso inertial loads. Copyright © 2012 Elsevier Ltd. All rights reserved.},
keywords = {*Accidents, *Neck Injuries/et [Etiology], *Neck Injuries/pp [Physiopathology], Acceleration, ANALYSIS of variance, Biomechanical Phenomena, Cadaver, Humans, Manikins, Rotation, Traffic, VIDEO recording},
pubstate = {published},
tppubtype = {article}
}
Estevan, I; Alvarez, O; Falco, C; Molina-Garcia, J; Castillo, I
Impact force and time analysis influenced by execution distance in a roundhouse kick to the head in taekwondo Journal Article
In: Journal of Strength & Conditioning Research, vol. 25, no. 10, pp. 2851–2856, 2011.
Abstract | BibTeX | Tags: *HEAD, *Martial Arts/ph [Physiology], *Task Performance and Analysis, adult, Biomechanical Phenomena, Humans, Male, Young Adult
@article{Estevan2011,
title = {Impact force and time analysis influenced by execution distance in a roundhouse kick to the head in taekwondo},
author = {Estevan, I and Alvarez, O and Falco, C and Molina-Garcia, J and Castillo, I},
year = {2011},
date = {2011-01-01},
journal = {Journal of Strength \& Conditioning Research},
volume = {25},
number = {10},
pages = {2851--2856},
abstract = {The execution distance is a tactic factor that affects mechanical performance and execution technique in taekwondo. This study analyzes the roundhouse kick to the head by comparing the maximum impact force, execution time, and impact time in 3 distances according to the athletes' competition level. It also analyzes the relationship between impact force and weight in each group. It examines whether the execution distance affects the maximum impact force, execution time, and impact time, in each level group or 2 different competition levels. Participants were 27 male taekwondo players (13 medallists and 14 nonmedallists). The medallists executed the roundhouse kick to the head with greater impact force and in a shorter execution time than did the nonmedallists when they kicked from any distance different to their combat distance. However, the results showed that the execution distance is influential in the execution time and impact time in the nonmedallist group. It is considered appropriate to orientate the high-level competitors to train for offensive actions from any distance similar to the long execution distance because it offers equally effectiveness and a greater security against the opponent. Also, practitioners should focus their training to improve time performance because it is more affected by distance than impact force.},
keywords = {*HEAD, *Martial Arts/ph [Physiology], *Task Performance and Analysis, adult, Biomechanical Phenomena, Humans, Male, Young Adult},
pubstate = {published},
tppubtype = {article}
}
Theobald, P; Whitelegg, L; Nokes, L D; Jones, M D
The predicted risk of head injury from fall-related impacts on to third-generation artificial turf and grass soccer surfaces: a comparative biomechanical analysis Journal Article
In: Sports Biomechanics, vol. 9, no. 1, pp. 29–37, 2010.
Abstract | BibTeX | Tags: *Athletic Injuries/et [Etiology], *Brain Injuries/et [Etiology], *Soccer/in [Injuries], Accidental Falls, Biomechanical Phenomena, Humans, Injury Severity Score, Poaceae, Risk
@article{Theobald2010,
title = {The predicted risk of head injury from fall-related impacts on to third-generation artificial turf and grass soccer surfaces: a comparative biomechanical analysis},
author = {Theobald, P and Whitelegg, L and Nokes, L D and Jones, M D},
year = {2010},
date = {2010-01-01},
journal = {Sports Biomechanics},
volume = {9},
number = {1},
pages = {29--37},
abstract = {The risk of soccer players sustaining mild traumatic brain injury (MTBI) following head impact with a playing surface is unclear. This study investigates MTBI by performing headform impact tests from varying heights onto a range of third-generation artificial turf surfaces. Each turf was prepared as per manufacturers specifications within a laboratory, before being tested immediately following installation and then again after a bedding-in period. Each turf was tested dry and when wetted to saturation. Data from the laboratory tests were compared to an in situ third-generation surface and a professional grass surface. The surface performance threshold was set at a head impact criterion (HIC) = 400, which equates to a 10% risk of the head impact causing MTBI. All six third-generation surfaces had a \> 10% risk of MTBI from a fall \> 0.77 m; the inferior surfaces required a fall from just 0.46 m to have a 10% MTBI risk. Wetting the artificial turf did not produce a statistically significant improvement (P \> 0.01). The in situ third-generation playing surface produced HIC values within the range of bedded-in experimental values. However, the natural turf pitch was the superior performer--necessitating fall heights exceeding those achievable during games to achieve HIC = 400.},
keywords = {*Athletic Injuries/et [Etiology], *Brain Injuries/et [Etiology], *Soccer/in [Injuries], Accidental Falls, Biomechanical Phenomena, Humans, Injury Severity Score, Poaceae, Risk},
pubstate = {published},
tppubtype = {article}
}
Depreitere, B; Van Lierde, C; Vander Sloten, J; Van der Perre, G; Van Audekercke, R; Plets, C; Goffin, J
Lateral head impacts and protection of the temporal area by bicycle safety helmets Journal Article
In: Journal of Trauma-Injury Infection & Critical Care, vol. 62, no. 6, pp. 1440–1445, 2007.
Abstract | BibTeX | Tags: *Bicycling, *HEAD injuries, *Head Protective Devices, *Skull Fractures, *Temporal Bone/in [Injuries], Athletic Injuries/pc [Prevention & Control], Biomechanical Phenomena, Cadaver, Closed/pc [Prevention & Control], Humans
@article{Depreitere2007,
title = {Lateral head impacts and protection of the temporal area by bicycle safety helmets},
author = {Depreitere, B and {Van Lierde}, C and {Vander Sloten}, J and {Van der Perre}, G and {Van Audekercke}, R and Plets, C and Goffin, J},
year = {2007},
date = {2007-01-01},
journal = {Journal of Trauma-Injury Infection \& Critical Care},
volume = {62},
number = {6},
pages = {1440--1445},
abstract = {BACKGROUND: The protective effectiveness of bicycle helmets has been demonstrated in several epidemiologic studies. However, the temple region is only minimally covered by most helmet models. Impact tests were performed on human cadavers to investigate whether current bicycle helmets are capable of preventing direct contact on the temporal area in side impacts. METHODS: Lateral head impacts, corresponding to a force load of 15,000 N on an nonhelmeted head, were applied on 11 helmeted cadavers by a steel pendulum with a flat impact surface, and the contact between the impactor plate and the temporal and zygomatic area was investigated by means of paint transfer. In eight tests, a common design bicycle helmet was used, whereas in three tests the helmets provided larger temporal coverage (temporal helmet edge \<10 mm above Frankfort plane). The skulls were inspected for fractures. RESULTS: In seven of the eight tests with common design bicycle helmets, contact had occurred and in one of these a skull fracture was seen. The helmets with a larger temporal coverage consistently prevented such contact loading. CONCLUSIONS: The common designs of commercially available bicycle helmets do not prevent direct contact loading on the temporal and zygomatic arch region and this contact loading is potentially harmful. The present preliminary study strongly questions the effectiveness of these helmets in providing accurate protection of the temporal and zygomatic area.},
keywords = {*Bicycling, *HEAD injuries, *Head Protective Devices, *Skull Fractures, *Temporal Bone/in [Injuries], Athletic Injuries/pc [Prevention \& Control], Biomechanical Phenomena, Cadaver, Closed/pc [Prevention \& Control], Humans},
pubstate = {published},
tppubtype = {article}
}
Davis, A E
Mechanisms of traumatic brain injury: biomechanical, structural and cellular considerations Journal Article
In: Critical Care Nursing Quarterly, vol. 23, no. 3, pp. 1–13, 2000.
Abstract | BibTeX | Tags: *Brain Injuries/pa [Pathology], *Brain Injuries/pp [Physiopathology], Biomechanical Phenomena, Brain Injuries/cl [Classification], Brain Injuries/co [Complications], Brain/me [Metabolism], Brain/pa [Pathology], Humans, intracranial hemorrhage, Neurons/me [Metabolism], Neurons/pa [Pathology], Nonpenetrating/pa [Pathology], Nonpenetrating/pp [Physiopathology], Skull Fractures/pa [Pathology], Skull Fractures/pp [Physiopathology], Traumatic/pa [Pathology], Traumatic/pp [Physiopatho, Wounds
@article{Davis2000,
title = {Mechanisms of traumatic brain injury: biomechanical, structural and cellular considerations},
author = {Davis, A E},
year = {2000},
date = {2000-01-01},
journal = {Critical Care Nursing Quarterly},
volume = {23},
number = {3},
pages = {1--13},
abstract = {Traumatic brain injury (TBI) is a public health problem of great concern, because it affects more than 2 million individuals each year. TBI occurs as a result of motor vehicle crashes, falls, and sports-related events. Biomechanical mechanisms occurring at the time of the injury initiate primary and secondary injuries that evolve over several days. In this article the relationship between an blunt injury event and the subsequent damage produced is addressed. Mechanisms of brain injury from biomechanics to cellular pathobiology are presented. Primary and secondary injuries are differentiated, and specific focal and diffuse clinical syndromes are described. Cellular mechanisms responsible for injury are also addressed, because they provide the unifying concepts across the many clinical syndromes so often discussed separately in reviews of traumatic brain injury. [References: 26]},
keywords = {*Brain Injuries/pa [Pathology], *Brain Injuries/pp [Physiopathology], Biomechanical Phenomena, Brain Injuries/cl [Classification], Brain Injuries/co [Complications], Brain/me [Metabolism], Brain/pa [Pathology], Humans, intracranial hemorrhage, Neurons/me [Metabolism], Neurons/pa [Pathology], Nonpenetrating/pa [Pathology], Nonpenetrating/pp [Physiopathology], Skull Fractures/pa [Pathology], Skull Fractures/pp [Physiopathology], Traumatic/pa [Pathology], Traumatic/pp [Physiopatho, Wounds},
pubstate = {published},
tppubtype = {article}
}
Perry, C E; Buhrman, J R
Effect of helmet inertial properties on head and neck response during +Gz impact accelerations Journal Article
In: Journal of Gravitational Physiology: a Journal of the International Society for Gravitational Physiology, vol. 2, no. 1, pp. P88–91, 1995.
Abstract | BibTeX | Tags: *Acceleration/ae [Adverse Effects], *Head Protective Devices, *Neck/ph [Physiology], Aircraft, Aviation, Biomechanical Phenomena, Computer simulation, Equipment Design, Head Movements, Humans, Military personnel, Motion, Neck Injuries, SAFETY
@article{Perry1995,
title = {Effect of helmet inertial properties on head and neck response during +Gz impact accelerations},
author = {Perry, C E and Buhrman, J R},
year = {1995},
date = {1995-01-01},
journal = {Journal of Gravitational Physiology: a Journal of the International Society for Gravitational Physiology},
volume = {2},
number = {1},
pages = {P88--91},
abstract = {The objective of the test program was to study the effect of parametric changes in helmet inertial properties on the biodynamic response of human volunteers subjected to +Gz impact accelerations. Test data was used to drive a computer model (DYNAMAN) to estimate the loads and torques in the neck during impact. Currently, only seven of eleven test cells with variations in the inertial properties of the helmet along the x-axis of the head have been analyzed. Preliminary data analysis indicates that the biodynamic response of the head under the tested conditions is slightly more sensitive to the moment of inertia of the helmet than its weight alone even though both variables showed a general trend for the head accelerations (linear and angular) to increase. It has been shown that the model can give good estimates of the compression loads in the neck, but that the torque estimates will be low, possibly by a factor of three. Further refinements of the neck joint parameters in the model will be required in order to increase the motion of the head segment during impact acceleration and will be done prior to completing the remaining test cell analysis. Finally, all the test data will be evaluated to determine if the current interim head criteria require modification.},
keywords = {*Acceleration/ae [Adverse Effects], *Head Protective Devices, *Neck/ph [Physiology], Aircraft, Aviation, Biomechanical Phenomena, Computer simulation, Equipment Design, Head Movements, Humans, Military personnel, Motion, Neck Injuries, SAFETY},
pubstate = {published},
tppubtype = {article}
}
Wu, L C; Nangia, V; Bui, K; Hammoor, B; Kurt, M; Hernandez, F; Kuo, C; Camarillo, D B
In Vivo Evaluation of Wearable Head Impact Sensors Journal Article
In: Annals of Biomedical Engineering, vol. 44, no. 4, pp. 1234–1245, 2016.
@article{Wu2016,
title = {In Vivo Evaluation of Wearable Head Impact Sensors},
author = {Wu, L C and Nangia, V and Bui, K and Hammoor, B and Kurt, M and Hernandez, F and Kuo, C and Camarillo, D B},
year = {2016},
date = {2016-01-01},
journal = {Annals of Biomedical Engineering},
volume = {44},
number = {4},
pages = {1234--1245},
abstract = {Inertial sensors are commonly used to measure human head motion. Some sensors have been tested with dummy or cadaver experiments with mixed results, and methods to evaluate sensors in vivo are lacking. Here we present an in vivo method using high speed video to test teeth-mounted (mouthguard), soft tissue-mounted (skin patch), and headgear-mounted (skull cap) sensors during 6-13 g sagittal soccer head impacts. Sensor coupling to the skull was quantified by displacement from an ear-canal reference. Mouthguard displacements were within video measurement error (\<1 mm), while the skin patch and skull cap displaced up to 4 and 13 mm from the ear-canal reference, respectively. We used the mouthguard, which had the least displacement from skull, as the reference to assess 6-degree-of-freedom skin patch and skull cap measurements. Linear and rotational acceleration magnitudes were over-predicted by both the skin patch (with 120% NRMS error for a(mag), 290% for alpha(mag)) and the skull cap (320% NRMS error for a(mag), 500% for alpha(mag)). Such over-predictions were largely due to out-of-plane motion. To model sensor error, we found that in-plane skin patch linear acceleration in the anterior-posterior direction could be modeled by an underdamped viscoelastic system. In summary, the mouthguard showed tighter skull coupling than the other sensor mounting approaches. Furthermore, the in vivo methods presented are valuable for investigating skull acceleration sensor technologies.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Richards, D; Ivarsson, B J; Scher, I; Hoover, R; Rodowicz, K; Cripton, P
Ice hockey shoulder pad design and the effect on head response during shoulder-to-head impacts Journal Article
In: Sports Biomechanics, vol. 15, no. 4, pp. 385–396, 2016.
@article{Richards2016,
title = {Ice hockey shoulder pad design and the effect on head response during shoulder-to-head impacts},
author = {Richards, D and Ivarsson, B J and Scher, I and Hoover, R and Rodowicz, K and Cripton, P},
year = {2016},
date = {2016-01-01},
journal = {Sports Biomechanics},
volume = {15},
number = {4},
pages = {385--396},
abstract = {Ice hockey body checks involving direct shoulder-to-head contact frequently result in head injury. In the current study, we examined the effect of shoulder pad style on the likelihood of head injury from a shoulder-to-head check. Shoulder-to-head body checks were simulated by swinging a modified Hybrid-III anthropomorphic test device (ATD) with and without shoulder pads into a stationary Hybrid-III ATD at 21 km/h. Tests were conducted with three different styles of shoulder pads (traditional, integrated and tethered) and without shoulder pads for the purpose of control. Head response kinematics for the stationary ATD were measured. Compared to the case of no shoulder pads, the three different pad styles significantly (p \< 0.05) reduced peak resultant linear head accelerations of the stationary ATD by 35-56%. The integrated shoulder pads reduced linear head accelerations by an additional 18-21% beyond the other two styles of shoulder pads. The data presented here suggest that shoulder pads can be designed to help protect the head of the struck player in a shoulder-to-head check.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Williams, R M; Dowling, M; O'Connor, K L
Head Impact Measurement Devices Journal Article
In: Sports & Health, vol. 8, no. 3, pp. 270–273, 2016.
@article{Williams2016b,
title = {Head Impact Measurement Devices},
author = {Williams, R M and Dowling, M and O'Connor, K L},
year = {2016},
date = {2016-01-01},
journal = {Sports \& Health},
volume = {8},
number = {3},
pages = {270--273},
abstract = {CONTEXT: Concussive injuries are at the forefront of sports medicine research. Recently, researchers have used a variety of head- and helmet-based impact-monitoring devices to quantify impacts sustained during contact sport participation. This review provides an up-to-date collection of head accelerometer use at the youth, high school, and collegiate levels. EVIDENCE ACQUISITION: PubMed was searched for articles published between 1980 and 2015 using the terms accelerometer and concussion, impact sensor and concussion, head impact telemetry system, head impact telemetry, and linear acceleration and concussion. An additional Google search was performed to capture devices without publications. STUDY DESIGN: Clinical review. LEVEL OF EVIDENCE: Level 4. RESULTS: Twenty-four products track and/or record head impact for clinical or research use. Ten of these head impact devices have publications supporting their utility. CONCLUSION: Head impact measuring devices can describe athlete exposure in terms of magnitude and/or frequency, highlighting their utility within a multimodal approach for concussion assessment and diagnosis.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Little, C E; Emery, C; Black, A; Scott, S H; Meeuwisse, W; Nettel-Aguirre, A; Benson, B; Dukelow, S
Test-retest reliability of KINARM robot sensorimotor and cognitive assessment: in pediatric ice hockey players Journal Article
In: Journal of Neuroengineering & Rehabilitation, vol. 12, pp. 78, 2015.
@article{Little2015,
title = {Test-retest reliability of KINARM robot sensorimotor and cognitive assessment: in pediatric ice hockey players},
author = {Little, C E and Emery, C and Black, A and Scott, S H and Meeuwisse, W and Nettel-Aguirre, A and Benson, B and Dukelow, S},
year = {2015},
date = {2015-01-01},
journal = {Journal of Neuroengineering \& Rehabilitation},
volume = {12},
pages = {78},
abstract = {BACKGROUND: Better diagnostic and prognostic tools are needed to address issues related to early diagnosis and management of concussion across the continuum of aging but particularly in children and adolescents. The purpose of the current study was to evaluate the reliability of robotic technology (KINARM robot) assessments of reaching, position sense, bimanual motor function, visuospatial skills, attention and decision making in youth ice hockey players (ages 10-14). METHODS: Thirty-four male children attended two testing days, one week apart. On day one, each subject completed five tasks on the robot with two examiners (alternating examiner sequence); the 2(nd) examiner followed the same procedure as the 1(st) immediately afterwards. One consistent examiner tested subjects one week later. This is a test-retest reliability study. The robotic tasks characterize sensorimotor and/or cognitive performance; 63 parameters from 5 tasks are reported. Session 1 was the 1(st) time the subject performed the 5 tasks, session 2 the 2(nd) time on day 1, and session 3 one week following. RESULTS: Intra-class correlation coefficients ranged from 0.06 to 0.91 and 0.09 to 0.90 for session 1 to 2 and 2 to 3, respectively. Bland-Altman plots showed agreement in a majority of the parameters and a learning effect in 25 % and 24 % of parameters in session 1 vs 2 and 1 vs 3, respectively but none for session 2 vs 3. Of those that showed a learning effect, only 8 % of parameters in session 1 vs 2 and 10 % in session 1 vs 3 had a clinical relevance measure\>0.8. CONCLUSIONS: The relative homogeneity of the sample and the effect of learning seen in some of the task parameters appears to have negatively impacted the intra-class correlation coefficients from session 1 to 2, with less impact for 2 to 3. The Bland-Altman analysis supports good absolute reliability in healthy male children with no neurological impairment ranging in age from 10 to 14. The clinically relevant learning effect seen, in a small number of parameters could be addressed by creating a learning effect adjustment factor and/or implementing a practice session, which would eliminate the learning effect.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Lockhart, P A; Cronin, D S
Helmet liner evaluation to mitigate head response from primary blast exposure Journal Article
In: Computer Methods in Biomechanics & Biomedical Engineering, vol. 18, no. 6, pp. 635–645, 2015.
@article{Lockhart2015,
title = {Helmet liner evaluation to mitigate head response from primary blast exposure},
author = {Lockhart, P A and Cronin, D S},
year = {2015},
date = {2015-01-01},
journal = {Computer Methods in Biomechanics \& Biomedical Engineering},
volume = {18},
number = {6},
pages = {635--645},
abstract = {Head injury resulting from blast loading, including mild traumatic brain injury, has been identified as an important blast-related injury in modern conflict zones. A study was undertaken to investigate potential protective ballistic helmet liner materials to mitigate primary blast injury using a detailed sagittal plane head finite element model, developed and validated against previous studies of head kinematics resulting from blast exposure. Five measures reflecting the potential for brain injury that were investigated included intracranial pressure, brain tissue strain, head acceleration (linear and rotational) and the head injury criterion. In simulations, these measures provided consistent predictions for typical blast loading scenarios. Considering mitigation, various characteristics of foam material response were investigated and a factor analysis was performed which showed that the four most significant were the interaction effects between modulus and hysteretic response, stress-strain response, damping factor and density. Candidate materials were then identified using the predicted optimal material values. Polymeric foam was found to meet the density and modulus requirements; however, for all significant parameters, higher strength foams, such as aluminum foam, were found to provide the highest reduction in the potential for injury when compared against the unprotected head.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Oeur, R A; Karton, C; Post, A; Rousseau, P; Hoshizaki, T B; Marshall, S; Brien, S E; Smith, A; Cusimano, M D; Gilchrist, M D
In: Journal of Neurosurgery, vol. 123, no. 2, pp. 415–422, 2015.
@article{Oeur2015,
title = {A comparison of head dynamic response and brain tissue stress and strain using accident reconstructions for concussion, concussion with persistent postconcussive symptoms, and subdural hematoma},
author = {Oeur, R A and Karton, C and Post, A and Rousseau, P and Hoshizaki, T B and Marshall, S and Brien, S E and Smith, A and Cusimano, M D and Gilchrist, M D},
doi = {10.3171/2014.10.JNS14440},
year = {2015},
date = {2015-01-01},
journal = {Journal of Neurosurgery},
volume = {123},
number = {2},
pages = {415--422},
abstract = {Object Concussions typically resolve within several days, but in a few cases the symptoms last for a month or longer and are termed persistent postconcussive symptoms (PPCS). These persisting symptoms may also be associated with more serious brain trauma similar to subdural hematoma (SDH). The objective of this study was to investigate the head dynamic and brain tissue responses of injury reconstructions resulting in concussion, PPCS, and SDH. Methods Reconstruction cases were obtained from sports medicine clinics and hospitals. All subjects received a direct blow to the head resulting in symptoms. Those symptoms that resolved in 9 days or fewer were defined as concussions (n = 3). Those with symptoms lasting longer than 18 months were defined as PPCS (n = 3), and 3 patients presented with SDHs (n = 3). A Hybrid III headform was used in reconstruction to obtain linear and rotational accelerations of the head. These dynamic response data were then input into the University College Dublin Brain Trauma Model to calculate maximum principal strain and von Mises stress. A Kruskal-Wallis test followed by Tukey post hoc tests were used to compare head dynamic and brain tissue responses between injury groups. Statistical significance was set at p \< 0.05. Results A significant difference was identified for peak resultant linear and rotational acceleration between injury groups. Post hoc analyses revealed the SDH group had higher linear and rotational acceleration responses (316 g and 23,181 rad/sec2, respectively) than the concussion group (149 g and 8111 rad/sec2, respectively; p \< 0.05). No significant differences were found between groups for either brain tissue measures of maximum principal strain or von Mises stress. Conclusions The reconstruction of accidents resulting in a concussion with transient symptoms (low severity) and SDHs revealed a positive relationship between an increase in head dynamic response and the risk for more serious brain injury. This type of relationship was not found for brain tissue stress and strain results derived by finite element analysis. Future research should be undertaken using a larger sample size to confirm these initial findings. Understanding the relationship between the head dynamic and brain tissue response and the nature of the injury provides important information for developing strategies for injury prevention. © AANS, 2015.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Hernandez, F; Shull, P B; Camarillo, D B
Evaluation of a laboratory model of human head impact biomechanics Journal Article
In: Journal of Biomechanics, vol. 48, no. 12, pp. 3469–3477, 2015.
@article{Hernandez2015,
title = {Evaluation of a laboratory model of human head impact biomechanics},
author = {Hernandez, F and Shull, P B and Camarillo, D B},
year = {2015},
date = {2015-01-01},
journal = {Journal of Biomechanics},
volume = {48},
number = {12},
pages = {3469--3477},
abstract = {This work describes methodology for evaluating laboratory models of head impact biomechanics. Using this methodology, we investigated: how closely does twin-wire drop testing model head rotation in American football impacts? Head rotation is believed to cause mild traumatic brain injury (mTBI) but helmet safety standards only model head translations believed to cause severe TBI. It is unknown whether laboratory head impact models in safety standards, like twin-wire drop testing, reproduce six degree-of-freedom (6DOF) head impact biomechanics that may cause mTBI. We compared 6DOF measurements of 421 American football head impacts to twin-wire drop tests at impact sites and velocities weighted to represent typical field exposure. The highest rotational velocities produced by drop testing were the 74th percentile of non-injury field impacts. For a given translational acceleration level, drop testing underestimated field rotational acceleration by 46% and rotational velocity by 72%. Primary rotational acceleration frequencies were much larger in drop tests ($sim$100 Hz) than field impacts ($sim$10 Hz). Drop testing was physically unable to produce acceleration directions common in field impacts. Initial conditions of a single field impact were highly resolved in stereo high-speed video and reconstructed in a drop test. Reconstruction results reflected aggregate trends of lower amplitude rotational velocity and higher frequency rotational acceleration in drop testing, apparently due to twin-wire constraints and the absence of a neck. These results suggest twin-wire drop testing is limited in modeling head rotation during impact, and motivate continued evaluation of head impact models to ensure helmets are tested under conditions that may cause mTBI. Copyright © 2015 Elsevier Ltd. All rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Kettner, M; Ramsthaler, F; Potente, S; Bockenheimer, A; Schmidt, P H; Schrodt, M
Blunt force impact to the head using a teeball bat: systematic comparison of physical and finite element modeling Journal Article
In: Forensic Science, Medicine & Pathology, vol. 10, no. 4, pp. 513–517, 2014.
@article{Kettner2014,
title = {Blunt force impact to the head using a teeball bat: systematic comparison of physical and finite element modeling},
author = {Kettner, M and Ramsthaler, F and Potente, S and Bockenheimer, A and Schmidt, P H and Schrodt, M},
year = {2014},
date = {2014-01-01},
journal = {Forensic Science, Medicine \& Pathology},
volume = {10},
number = {4},
pages = {513--517},
abstract = {Blunt head trauma secondary to violent actions with various weapons is frequently a cause of injury in forensic casework; differing striking tools have varying degrees of injury capacity. The systematic approach used to examine a 19-year-old student who was beaten with a wooden teeball bat will be described. The assailant stopped beating the student when the teeball bat broke into two pieces. The surviving victim sustained bruises and a forehead laceration. The State's Attorney assigned a forensic expert to examine whether the forces exerted on the victim's head (leading to the fracture of the bat) were potentially life threatening (e.g. causing cranial bone fractures). Physical modeling was conducted using a pigskin-covered polyethylene end cap cushioned by cellulose that was connected to a piezoelectric force gauge. Experiments with teeball bats weighing 295-485 g demonstrated that 12-20 kN forces were necessary to cause a comparable bat fracture. In addition to physical testing, a computer-aided simulation was conducted, utilizing a finite-element (FE) method. In the FE approach, after selecting for wood properties, a virtual bat was swung against a hemisphere comprising two layers that represented bone and soft tissue. Employing this model, a 17.6 kN force was calculated, with the highest fracture probability points resembling the fracture patterns of the physically tested bats.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
McIntosh, A S; Lai, A; Schilter, E
Bicycle helmets: head impact dynamics in helmeted and unhelmeted oblique impact tests Journal Article
In: Traffic Injury Prevention, vol. 14, no. 5, pp. 501–508, 2013.
@article{McIntosh2013,
title = {Bicycle helmets: head impact dynamics in helmeted and unhelmeted oblique impact tests},
author = {McIntosh, A S and Lai, A and Schilter, E},
year = {2013},
date = {2013-01-01},
journal = {Traffic Injury Prevention},
volume = {14},
number = {5},
pages = {501--508},
abstract = {OBJECTIVE: To assess the factors, including helmet use, that contribute to head linear and angular acceleration in bicycle crash simulation tests. METHOD: A series of laboratory tests was undertaken using an oblique impact rig. The impact rig included a drop assembly with a Hybrid III head and neck. The head struck a horizontally moving striker plate. Head linear and angular acceleration and striker plate force were measured. The Head Injury Criterion was derived. The following test parameters were varied: drop height to a maximum of 1.5 m, horizontal speed to a maximum of 25 km/h, helmet/no helmet, impact orientation/location, and restraint adjustment. Additional radial impacts were conducted on the same helmet models for comparison purposes. Descriptive statistics were derived and multiple regression was applied to examine the role of each parameter. RESULTS: Helmet use was the most significant factor in reducing the magnitude of all outcome variables. Linear acceleration and the Head Injury Criterion were influenced by the drop height, whereas angular acceleration tended to be influenced by the horizontal speed and impact orientation/location. The restraint adjustment influenced the outcome variables, with lower coefficients of variation observed with the tight restraint. CONCLUSIONS: The study reinforces the benefits of wearing a bicycle helmet in a crash. The study also demonstrates that helmets do not increase angular head acceleration. The study assists in establishing the need for an agreed-upon international oblique helmet test as well as the boundary conditions for oblique helmet testing.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Ivancic, P C
Neck injury response to direct head impact Journal Article
In: Accident Analysis & Prevention, vol. 50, pp. 323–329, 2013.
@article{Ivancic2013,
title = {Neck injury response to direct head impact},
author = {Ivancic, P C},
year = {2013},
date = {2013-01-01},
journal = {Accident Analysis \& Prevention},
volume = {50},
pages = {323--329},
abstract = {Previous in vivo studies have observed flexion of the upper or upper/middle cervical spine and extension at inferior spinal levels due to direct head impacts. These studies hypothesized that hyperflexion may contribute to injury of the upper or middle cervical spine during real-life head impact. Our objectives were to determine the cervical spine injury response to direct head impact, document injuries, and compare our results with previously reported in vivo data. Our model consisted of a human cadaver neck (n=6) mounted to the torso of a rear impact dummy and carrying a surrogate head. Rearward force was applied to the model's forehead using a cable and pulley system and free-falling mass of 3.6kg followed by 16.7kg. High-speed digital cameras tracked head, vertebral, and pelvic motions. Average peak spinal rotations observed during impact were statistically compared (P\<0.05) to physiological ranges obtained from intact flexibility tests. Peak head impact force was 249 and 504N for the 3.6 and 16.7kg free-falling masses, respectively. Occipital condyle loads reached 205.3N posterior shear, 331.4N compression, and 7.4Nm extension moment. We observed significant increases in intervertebral extension peaks above physiologic at C6/7 (26.3degree vs. 5.7degree) and C7/T1 (29.7degree vs. 4.6degree) and macroscopic ligamentous and osseous injuries at C6 through T1 due to the 504N impacts. Our results indicate that a rearward head shear force causes complex neck loads of posterior shear, compression, and extension moment sufficient to injure the lower cervical spine. Real-life neck injuries due to motor vehicle crashes, sports impacts, or falls are likely due to combined loads transferred to the neck by direct head impact and torso inertial loads. Copyright © 2012 Elsevier Ltd. All rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Estevan, I; Alvarez, O; Falco, C; Molina-Garcia, J; Castillo, I
Impact force and time analysis influenced by execution distance in a roundhouse kick to the head in taekwondo Journal Article
In: Journal of Strength & Conditioning Research, vol. 25, no. 10, pp. 2851–2856, 2011.
@article{Estevan2011,
title = {Impact force and time analysis influenced by execution distance in a roundhouse kick to the head in taekwondo},
author = {Estevan, I and Alvarez, O and Falco, C and Molina-Garcia, J and Castillo, I},
year = {2011},
date = {2011-01-01},
journal = {Journal of Strength \& Conditioning Research},
volume = {25},
number = {10},
pages = {2851--2856},
abstract = {The execution distance is a tactic factor that affects mechanical performance and execution technique in taekwondo. This study analyzes the roundhouse kick to the head by comparing the maximum impact force, execution time, and impact time in 3 distances according to the athletes' competition level. It also analyzes the relationship between impact force and weight in each group. It examines whether the execution distance affects the maximum impact force, execution time, and impact time, in each level group or 2 different competition levels. Participants were 27 male taekwondo players (13 medallists and 14 nonmedallists). The medallists executed the roundhouse kick to the head with greater impact force and in a shorter execution time than did the nonmedallists when they kicked from any distance different to their combat distance. However, the results showed that the execution distance is influential in the execution time and impact time in the nonmedallist group. It is considered appropriate to orientate the high-level competitors to train for offensive actions from any distance similar to the long execution distance because it offers equally effectiveness and a greater security against the opponent. Also, practitioners should focus their training to improve time performance because it is more affected by distance than impact force.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Theobald, P; Whitelegg, L; Nokes, L D; Jones, M D
The predicted risk of head injury from fall-related impacts on to third-generation artificial turf and grass soccer surfaces: a comparative biomechanical analysis Journal Article
In: Sports Biomechanics, vol. 9, no. 1, pp. 29–37, 2010.
@article{Theobald2010,
title = {The predicted risk of head injury from fall-related impacts on to third-generation artificial turf and grass soccer surfaces: a comparative biomechanical analysis},
author = {Theobald, P and Whitelegg, L and Nokes, L D and Jones, M D},
year = {2010},
date = {2010-01-01},
journal = {Sports Biomechanics},
volume = {9},
number = {1},
pages = {29--37},
abstract = {The risk of soccer players sustaining mild traumatic brain injury (MTBI) following head impact with a playing surface is unclear. This study investigates MTBI by performing headform impact tests from varying heights onto a range of third-generation artificial turf surfaces. Each turf was prepared as per manufacturers specifications within a laboratory, before being tested immediately following installation and then again after a bedding-in period. Each turf was tested dry and when wetted to saturation. Data from the laboratory tests were compared to an in situ third-generation surface and a professional grass surface. The surface performance threshold was set at a head impact criterion (HIC) = 400, which equates to a 10% risk of the head impact causing MTBI. All six third-generation surfaces had a \> 10% risk of MTBI from a fall \> 0.77 m; the inferior surfaces required a fall from just 0.46 m to have a 10% MTBI risk. Wetting the artificial turf did not produce a statistically significant improvement (P \> 0.01). The in situ third-generation playing surface produced HIC values within the range of bedded-in experimental values. However, the natural turf pitch was the superior performer--necessitating fall heights exceeding those achievable during games to achieve HIC = 400.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Depreitere, B; Van Lierde, C; Vander Sloten, J; Van der Perre, G; Van Audekercke, R; Plets, C; Goffin, J
Lateral head impacts and protection of the temporal area by bicycle safety helmets Journal Article
In: Journal of Trauma-Injury Infection & Critical Care, vol. 62, no. 6, pp. 1440–1445, 2007.
@article{Depreitere2007,
title = {Lateral head impacts and protection of the temporal area by bicycle safety helmets},
author = {Depreitere, B and {Van Lierde}, C and {Vander Sloten}, J and {Van der Perre}, G and {Van Audekercke}, R and Plets, C and Goffin, J},
year = {2007},
date = {2007-01-01},
journal = {Journal of Trauma-Injury Infection \& Critical Care},
volume = {62},
number = {6},
pages = {1440--1445},
abstract = {BACKGROUND: The protective effectiveness of bicycle helmets has been demonstrated in several epidemiologic studies. However, the temple region is only minimally covered by most helmet models. Impact tests were performed on human cadavers to investigate whether current bicycle helmets are capable of preventing direct contact on the temporal area in side impacts. METHODS: Lateral head impacts, corresponding to a force load of 15,000 N on an nonhelmeted head, were applied on 11 helmeted cadavers by a steel pendulum with a flat impact surface, and the contact between the impactor plate and the temporal and zygomatic area was investigated by means of paint transfer. In eight tests, a common design bicycle helmet was used, whereas in three tests the helmets provided larger temporal coverage (temporal helmet edge \<10 mm above Frankfort plane). The skulls were inspected for fractures. RESULTS: In seven of the eight tests with common design bicycle helmets, contact had occurred and in one of these a skull fracture was seen. The helmets with a larger temporal coverage consistently prevented such contact loading. CONCLUSIONS: The common designs of commercially available bicycle helmets do not prevent direct contact loading on the temporal and zygomatic arch region and this contact loading is potentially harmful. The present preliminary study strongly questions the effectiveness of these helmets in providing accurate protection of the temporal and zygomatic area.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Davis, A E
Mechanisms of traumatic brain injury: biomechanical, structural and cellular considerations Journal Article
In: Critical Care Nursing Quarterly, vol. 23, no. 3, pp. 1–13, 2000.
@article{Davis2000,
title = {Mechanisms of traumatic brain injury: biomechanical, structural and cellular considerations},
author = {Davis, A E},
year = {2000},
date = {2000-01-01},
journal = {Critical Care Nursing Quarterly},
volume = {23},
number = {3},
pages = {1--13},
abstract = {Traumatic brain injury (TBI) is a public health problem of great concern, because it affects more than 2 million individuals each year. TBI occurs as a result of motor vehicle crashes, falls, and sports-related events. Biomechanical mechanisms occurring at the time of the injury initiate primary and secondary injuries that evolve over several days. In this article the relationship between an blunt injury event and the subsequent damage produced is addressed. Mechanisms of brain injury from biomechanics to cellular pathobiology are presented. Primary and secondary injuries are differentiated, and specific focal and diffuse clinical syndromes are described. Cellular mechanisms responsible for injury are also addressed, because they provide the unifying concepts across the many clinical syndromes so often discussed separately in reviews of traumatic brain injury. [References: 26]},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Perry, C E; Buhrman, J R
Effect of helmet inertial properties on head and neck response during +Gz impact accelerations Journal Article
In: Journal of Gravitational Physiology: a Journal of the International Society for Gravitational Physiology, vol. 2, no. 1, pp. P88–91, 1995.
@article{Perry1995,
title = {Effect of helmet inertial properties on head and neck response during +Gz impact accelerations},
author = {Perry, C E and Buhrman, J R},
year = {1995},
date = {1995-01-01},
journal = {Journal of Gravitational Physiology: a Journal of the International Society for Gravitational Physiology},
volume = {2},
number = {1},
pages = {P88--91},
abstract = {The objective of the test program was to study the effect of parametric changes in helmet inertial properties on the biodynamic response of human volunteers subjected to +Gz impact accelerations. Test data was used to drive a computer model (DYNAMAN) to estimate the loads and torques in the neck during impact. Currently, only seven of eleven test cells with variations in the inertial properties of the helmet along the x-axis of the head have been analyzed. Preliminary data analysis indicates that the biodynamic response of the head under the tested conditions is slightly more sensitive to the moment of inertia of the helmet than its weight alone even though both variables showed a general trend for the head accelerations (linear and angular) to increase. It has been shown that the model can give good estimates of the compression loads in the neck, but that the torque estimates will be low, possibly by a factor of three. Further refinements of the neck joint parameters in the model will be required in order to increase the motion of the head segment during impact acceleration and will be done prior to completing the remaining test cell analysis. Finally, all the test data will be evaluated to determine if the current interim head criteria require modification.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Wu, L C; Nangia, V; Bui, K; Hammoor, B; Kurt, M; Hernandez, F; Kuo, C; Camarillo, D B
In Vivo Evaluation of Wearable Head Impact Sensors Journal Article
In: Annals of Biomedical Engineering, vol. 44, no. 4, pp. 1234–1245, 2016.
Abstract | BibTeX | Tags: *Head Movements/ph [Physiology], *Models, *Soccer/ph [Physiology], *Telemetry/is [Instrumentation], adult, Biological, Biomechanical Phenomena, Craniocerebral Trauma, Humans, Male, MOUTH protectors, Skin, Soccer/in [Injuries], VIDEO recording
@article{Wu2016,
title = {In Vivo Evaluation of Wearable Head Impact Sensors},
author = {Wu, L C and Nangia, V and Bui, K and Hammoor, B and Kurt, M and Hernandez, F and Kuo, C and Camarillo, D B},
year = {2016},
date = {2016-01-01},
journal = {Annals of Biomedical Engineering},
volume = {44},
number = {4},
pages = {1234--1245},
abstract = {Inertial sensors are commonly used to measure human head motion. Some sensors have been tested with dummy or cadaver experiments with mixed results, and methods to evaluate sensors in vivo are lacking. Here we present an in vivo method using high speed video to test teeth-mounted (mouthguard), soft tissue-mounted (skin patch), and headgear-mounted (skull cap) sensors during 6-13 g sagittal soccer head impacts. Sensor coupling to the skull was quantified by displacement from an ear-canal reference. Mouthguard displacements were within video measurement error (\<1 mm), while the skin patch and skull cap displaced up to 4 and 13 mm from the ear-canal reference, respectively. We used the mouthguard, which had the least displacement from skull, as the reference to assess 6-degree-of-freedom skin patch and skull cap measurements. Linear and rotational acceleration magnitudes were over-predicted by both the skin patch (with 120% NRMS error for a(mag), 290% for alpha(mag)) and the skull cap (320% NRMS error for a(mag), 500% for alpha(mag)). Such over-predictions were largely due to out-of-plane motion. To model sensor error, we found that in-plane skin patch linear acceleration in the anterior-posterior direction could be modeled by an underdamped viscoelastic system. In summary, the mouthguard showed tighter skull coupling than the other sensor mounting approaches. Furthermore, the in vivo methods presented are valuable for investigating skull acceleration sensor technologies.},
keywords = {*Head Movements/ph [Physiology], *Models, *Soccer/ph [Physiology], *Telemetry/is [Instrumentation], adult, Biological, Biomechanical Phenomena, Craniocerebral Trauma, Humans, Male, MOUTH protectors, Skin, Soccer/in [Injuries], VIDEO recording},
pubstate = {published},
tppubtype = {article}
}
Richards, D; Ivarsson, B J; Scher, I; Hoover, R; Rodowicz, K; Cripton, P
Ice hockey shoulder pad design and the effect on head response during shoulder-to-head impacts Journal Article
In: Sports Biomechanics, vol. 15, no. 4, pp. 385–396, 2016.
Abstract | BibTeX | Tags: *Craniocerebral Trauma/pc [Prevention & Control], *Head/ph [Physiology], *Hockey/ph [Physiology], *Protective Clothing, *Shoulder/ph [Physiology], Acceleration, Biomechanical Phenomena, Equipment Design, Humans, Male, Manikins, Materials testing, Reproducibility of Results, Risk Factors
@article{Richards2016,
title = {Ice hockey shoulder pad design and the effect on head response during shoulder-to-head impacts},
author = {Richards, D and Ivarsson, B J and Scher, I and Hoover, R and Rodowicz, K and Cripton, P},
year = {2016},
date = {2016-01-01},
journal = {Sports Biomechanics},
volume = {15},
number = {4},
pages = {385--396},
abstract = {Ice hockey body checks involving direct shoulder-to-head contact frequently result in head injury. In the current study, we examined the effect of shoulder pad style on the likelihood of head injury from a shoulder-to-head check. Shoulder-to-head body checks were simulated by swinging a modified Hybrid-III anthropomorphic test device (ATD) with and without shoulder pads into a stationary Hybrid-III ATD at 21 km/h. Tests were conducted with three different styles of shoulder pads (traditional, integrated and tethered) and without shoulder pads for the purpose of control. Head response kinematics for the stationary ATD were measured. Compared to the case of no shoulder pads, the three different pad styles significantly (p \< 0.05) reduced peak resultant linear head accelerations of the stationary ATD by 35-56%. The integrated shoulder pads reduced linear head accelerations by an additional 18-21% beyond the other two styles of shoulder pads. The data presented here suggest that shoulder pads can be designed to help protect the head of the struck player in a shoulder-to-head check.},
keywords = {*Craniocerebral Trauma/pc [Prevention \& Control], *Head/ph [Physiology], *Hockey/ph [Physiology], *Protective Clothing, *Shoulder/ph [Physiology], Acceleration, Biomechanical Phenomena, Equipment Design, Humans, Male, Manikins, Materials testing, Reproducibility of Results, Risk Factors},
pubstate = {published},
tppubtype = {article}
}
Williams, R M; Dowling, M; O'Connor, K L
Head Impact Measurement Devices Journal Article
In: Sports & Health, vol. 8, no. 3, pp. 270–273, 2016.
Abstract | BibTeX | Tags: *Accelerometry, *Athletic Injuries/di [Diagnosis], *Brain Concussion/di [Diagnosis], Athletic Injuries/pp [Physiopathology], Biomechanical Phenomena, Brain Concussion/pp [Physiopathology], Head Protective Devices, Head/pp [Physiopathology], Humans
@article{Williams2016b,
title = {Head Impact Measurement Devices},
author = {Williams, R M and Dowling, M and O'Connor, K L},
year = {2016},
date = {2016-01-01},
journal = {Sports \& Health},
volume = {8},
number = {3},
pages = {270--273},
abstract = {CONTEXT: Concussive injuries are at the forefront of sports medicine research. Recently, researchers have used a variety of head- and helmet-based impact-monitoring devices to quantify impacts sustained during contact sport participation. This review provides an up-to-date collection of head accelerometer use at the youth, high school, and collegiate levels. EVIDENCE ACQUISITION: PubMed was searched for articles published between 1980 and 2015 using the terms accelerometer and concussion, impact sensor and concussion, head impact telemetry system, head impact telemetry, and linear acceleration and concussion. An additional Google search was performed to capture devices without publications. STUDY DESIGN: Clinical review. LEVEL OF EVIDENCE: Level 4. RESULTS: Twenty-four products track and/or record head impact for clinical or research use. Ten of these head impact devices have publications supporting their utility. CONCLUSION: Head impact measuring devices can describe athlete exposure in terms of magnitude and/or frequency, highlighting their utility within a multimodal approach for concussion assessment and diagnosis.},
keywords = {*Accelerometry, *Athletic Injuries/di [Diagnosis], *Brain Concussion/di [Diagnosis], Athletic Injuries/pp [Physiopathology], Biomechanical Phenomena, Brain Concussion/pp [Physiopathology], Head Protective Devices, Head/pp [Physiopathology], Humans},
pubstate = {published},
tppubtype = {article}
}
Little, C E; Emery, C; Black, A; Scott, S H; Meeuwisse, W; Nettel-Aguirre, A; Benson, B; Dukelow, S
Test-retest reliability of KINARM robot sensorimotor and cognitive assessment: in pediatric ice hockey players Journal Article
In: Journal of Neuroengineering & Rehabilitation, vol. 12, pp. 78, 2015.
Abstract | BibTeX | Tags: *Brain Concussion/di [Diagnosis], *Brain Concussion/px [Psychology], *COGNITION, *Hockey/in [Injuries], *Robotics, *Sensation, Adolescent, Biomechanical Phenomena, Brain Concussion/pp [Physiopathology], Child, Computer simulation, Humans, learning, Longitudinal studies, Male, Neuropsychological Tests, Practice (Psychology), Prognosis, Prospective Studies, Psychomotor Performance/ph [Physiology], Reproducibility of Results, treatment outcome
@article{Little2015,
title = {Test-retest reliability of KINARM robot sensorimotor and cognitive assessment: in pediatric ice hockey players},
author = {Little, C E and Emery, C and Black, A and Scott, S H and Meeuwisse, W and Nettel-Aguirre, A and Benson, B and Dukelow, S},
year = {2015},
date = {2015-01-01},
journal = {Journal of Neuroengineering \& Rehabilitation},
volume = {12},
pages = {78},
abstract = {BACKGROUND: Better diagnostic and prognostic tools are needed to address issues related to early diagnosis and management of concussion across the continuum of aging but particularly in children and adolescents. The purpose of the current study was to evaluate the reliability of robotic technology (KINARM robot) assessments of reaching, position sense, bimanual motor function, visuospatial skills, attention and decision making in youth ice hockey players (ages 10-14). METHODS: Thirty-four male children attended two testing days, one week apart. On day one, each subject completed five tasks on the robot with two examiners (alternating examiner sequence); the 2(nd) examiner followed the same procedure as the 1(st) immediately afterwards. One consistent examiner tested subjects one week later. This is a test-retest reliability study. The robotic tasks characterize sensorimotor and/or cognitive performance; 63 parameters from 5 tasks are reported. Session 1 was the 1(st) time the subject performed the 5 tasks, session 2 the 2(nd) time on day 1, and session 3 one week following. RESULTS: Intra-class correlation coefficients ranged from 0.06 to 0.91 and 0.09 to 0.90 for session 1 to 2 and 2 to 3, respectively. Bland-Altman plots showed agreement in a majority of the parameters and a learning effect in 25 % and 24 % of parameters in session 1 vs 2 and 1 vs 3, respectively but none for session 2 vs 3. Of those that showed a learning effect, only 8 % of parameters in session 1 vs 2 and 10 % in session 1 vs 3 had a clinical relevance measure\>0.8. CONCLUSIONS: The relative homogeneity of the sample and the effect of learning seen in some of the task parameters appears to have negatively impacted the intra-class correlation coefficients from session 1 to 2, with less impact for 2 to 3. The Bland-Altman analysis supports good absolute reliability in healthy male children with no neurological impairment ranging in age from 10 to 14. The clinically relevant learning effect seen, in a small number of parameters could be addressed by creating a learning effect adjustment factor and/or implementing a practice session, which would eliminate the learning effect.},
keywords = {*Brain Concussion/di [Diagnosis], *Brain Concussion/px [Psychology], *COGNITION, *Hockey/in [Injuries], *Robotics, *Sensation, Adolescent, Biomechanical Phenomena, Brain Concussion/pp [Physiopathology], Child, Computer simulation, Humans, learning, Longitudinal studies, Male, Neuropsychological Tests, Practice (Psychology), Prognosis, Prospective Studies, Psychomotor Performance/ph [Physiology], Reproducibility of Results, treatment outcome},
pubstate = {published},
tppubtype = {article}
}
Lockhart, P A; Cronin, D S
Helmet liner evaluation to mitigate head response from primary blast exposure Journal Article
In: Computer Methods in Biomechanics & Biomedical Engineering, vol. 18, no. 6, pp. 635–645, 2015.
Abstract | BibTeX | Tags: *Blast Injuries/pc [Prevention & Control], *Craniocerebral Trauma/pc [Prevention & Control], *Explosions, *Head Protective Devices, Acceleration, Aluminum/ch [Chemistry], Biomechanical Phenomena, brain concussion, Brain Injuries, Brain/ph [Physiology], Computer simulation, CPD4NFA903 (Aluminum), Equipment Design, Head, Humans, intracranial pressure, Male, Materials testing
@article{Lockhart2015,
title = {Helmet liner evaluation to mitigate head response from primary blast exposure},
author = {Lockhart, P A and Cronin, D S},
year = {2015},
date = {2015-01-01},
journal = {Computer Methods in Biomechanics \& Biomedical Engineering},
volume = {18},
number = {6},
pages = {635--645},
abstract = {Head injury resulting from blast loading, including mild traumatic brain injury, has been identified as an important blast-related injury in modern conflict zones. A study was undertaken to investigate potential protective ballistic helmet liner materials to mitigate primary blast injury using a detailed sagittal plane head finite element model, developed and validated against previous studies of head kinematics resulting from blast exposure. Five measures reflecting the potential for brain injury that were investigated included intracranial pressure, brain tissue strain, head acceleration (linear and rotational) and the head injury criterion. In simulations, these measures provided consistent predictions for typical blast loading scenarios. Considering mitigation, various characteristics of foam material response were investigated and a factor analysis was performed which showed that the four most significant were the interaction effects between modulus and hysteretic response, stress-strain response, damping factor and density. Candidate materials were then identified using the predicted optimal material values. Polymeric foam was found to meet the density and modulus requirements; however, for all significant parameters, higher strength foams, such as aluminum foam, were found to provide the highest reduction in the potential for injury when compared against the unprotected head.},
keywords = {*Blast Injuries/pc [Prevention \& Control], *Craniocerebral Trauma/pc [Prevention \& Control], *Explosions, *Head Protective Devices, Acceleration, Aluminum/ch [Chemistry], Biomechanical Phenomena, brain concussion, Brain Injuries, Brain/ph [Physiology], Computer simulation, CPD4NFA903 (Aluminum), Equipment Design, Head, Humans, intracranial pressure, Male, Materials testing},
pubstate = {published},
tppubtype = {article}
}
Oeur, R A; Karton, C; Post, A; Rousseau, P; Hoshizaki, T B; Marshall, S; Brien, S E; Smith, A; Cusimano, M D; Gilchrist, M D
In: Journal of Neurosurgery, vol. 123, no. 2, pp. 415–422, 2015.
Abstract | Links | BibTeX | Tags: accident, Accident reconstruction, accidental injury, Accidents, Adolescent, adult, Article, Biomechanical Phenomena, Biomechanics, brain, brain concussion, brain stem, brain tissue, Cerebellum, clinical article, comparative study, Concussion, controlled study, Female, finite element analysis, Finite element modelling, gray matter, Hematoma, human, Humans, Hybrid iii headform, injury severity, laboratory test, Male, Mechanical, mechanical stress, middle aged, pathology, Pathophysiology, Persistent postconcussive symptoms, PHYSIOLOGY, Post Hoc Analysis, Post-Concussion Syndrome, postconcussion syndrome, priority journal, shear stress, simulation, SPORTS medicine, STATISTICAL significance, Stress, stress strain relationship, Subdural, subdural hematoma, traumatic brain injury, white matter, Young Adult
@article{Oeur2015,
title = {A comparison of head dynamic response and brain tissue stress and strain using accident reconstructions for concussion, concussion with persistent postconcussive symptoms, and subdural hematoma},
author = {Oeur, R A and Karton, C and Post, A and Rousseau, P and Hoshizaki, T B and Marshall, S and Brien, S E and Smith, A and Cusimano, M D and Gilchrist, M D},
doi = {10.3171/2014.10.JNS14440},
year = {2015},
date = {2015-01-01},
journal = {Journal of Neurosurgery},
volume = {123},
number = {2},
pages = {415--422},
abstract = {Object Concussions typically resolve within several days, but in a few cases the symptoms last for a month or longer and are termed persistent postconcussive symptoms (PPCS). These persisting symptoms may also be associated with more serious brain trauma similar to subdural hematoma (SDH). The objective of this study was to investigate the head dynamic and brain tissue responses of injury reconstructions resulting in concussion, PPCS, and SDH. Methods Reconstruction cases were obtained from sports medicine clinics and hospitals. All subjects received a direct blow to the head resulting in symptoms. Those symptoms that resolved in 9 days or fewer were defined as concussions (n = 3). Those with symptoms lasting longer than 18 months were defined as PPCS (n = 3), and 3 patients presented with SDHs (n = 3). A Hybrid III headform was used in reconstruction to obtain linear and rotational accelerations of the head. These dynamic response data were then input into the University College Dublin Brain Trauma Model to calculate maximum principal strain and von Mises stress. A Kruskal-Wallis test followed by Tukey post hoc tests were used to compare head dynamic and brain tissue responses between injury groups. Statistical significance was set at p \< 0.05. Results A significant difference was identified for peak resultant linear and rotational acceleration between injury groups. Post hoc analyses revealed the SDH group had higher linear and rotational acceleration responses (316 g and 23,181 rad/sec2, respectively) than the concussion group (149 g and 8111 rad/sec2, respectively; p \< 0.05). No significant differences were found between groups for either brain tissue measures of maximum principal strain or von Mises stress. Conclusions The reconstruction of accidents resulting in a concussion with transient symptoms (low severity) and SDHs revealed a positive relationship between an increase in head dynamic response and the risk for more serious brain injury. This type of relationship was not found for brain tissue stress and strain results derived by finite element analysis. Future research should be undertaken using a larger sample size to confirm these initial findings. Understanding the relationship between the head dynamic and brain tissue response and the nature of the injury provides important information for developing strategies for injury prevention. © AANS, 2015.},
keywords = {accident, Accident reconstruction, accidental injury, Accidents, Adolescent, adult, Article, Biomechanical Phenomena, Biomechanics, brain, brain concussion, brain stem, brain tissue, Cerebellum, clinical article, comparative study, Concussion, controlled study, Female, finite element analysis, Finite element modelling, gray matter, Hematoma, human, Humans, Hybrid iii headform, injury severity, laboratory test, Male, Mechanical, mechanical stress, middle aged, pathology, Pathophysiology, Persistent postconcussive symptoms, PHYSIOLOGY, Post Hoc Analysis, Post-Concussion Syndrome, postconcussion syndrome, priority journal, shear stress, simulation, SPORTS medicine, STATISTICAL significance, Stress, stress strain relationship, Subdural, subdural hematoma, traumatic brain injury, white matter, Young Adult},
pubstate = {published},
tppubtype = {article}
}
Hernandez, F; Shull, P B; Camarillo, D B
Evaluation of a laboratory model of human head impact biomechanics Journal Article
In: Journal of Biomechanics, vol. 48, no. 12, pp. 3469–3477, 2015.
Abstract | BibTeX | Tags: *HEAD, *Laboratories, *Mechanical Phenomena, *Models, Acceleration, Biological, Biomechanical Phenomena, Brain Concussion/et [Etiology], Football/in [Injuries], Head Protective Devices, Humans, Male, Neck/ph [Physiology], Rotation, SAFETY
@article{Hernandez2015,
title = {Evaluation of a laboratory model of human head impact biomechanics},
author = {Hernandez, F and Shull, P B and Camarillo, D B},
year = {2015},
date = {2015-01-01},
journal = {Journal of Biomechanics},
volume = {48},
number = {12},
pages = {3469--3477},
abstract = {This work describes methodology for evaluating laboratory models of head impact biomechanics. Using this methodology, we investigated: how closely does twin-wire drop testing model head rotation in American football impacts? Head rotation is believed to cause mild traumatic brain injury (mTBI) but helmet safety standards only model head translations believed to cause severe TBI. It is unknown whether laboratory head impact models in safety standards, like twin-wire drop testing, reproduce six degree-of-freedom (6DOF) head impact biomechanics that may cause mTBI. We compared 6DOF measurements of 421 American football head impacts to twin-wire drop tests at impact sites and velocities weighted to represent typical field exposure. The highest rotational velocities produced by drop testing were the 74th percentile of non-injury field impacts. For a given translational acceleration level, drop testing underestimated field rotational acceleration by 46% and rotational velocity by 72%. Primary rotational acceleration frequencies were much larger in drop tests ($sim$100 Hz) than field impacts ($sim$10 Hz). Drop testing was physically unable to produce acceleration directions common in field impacts. Initial conditions of a single field impact were highly resolved in stereo high-speed video and reconstructed in a drop test. Reconstruction results reflected aggregate trends of lower amplitude rotational velocity and higher frequency rotational acceleration in drop testing, apparently due to twin-wire constraints and the absence of a neck. These results suggest twin-wire drop testing is limited in modeling head rotation during impact, and motivate continued evaluation of head impact models to ensure helmets are tested under conditions that may cause mTBI. Copyright © 2015 Elsevier Ltd. All rights reserved.},
keywords = {*HEAD, *Laboratories, *Mechanical Phenomena, *Models, Acceleration, Biological, Biomechanical Phenomena, Brain Concussion/et [Etiology], Football/in [Injuries], Head Protective Devices, Humans, Male, Neck/ph [Physiology], Rotation, SAFETY},
pubstate = {published},
tppubtype = {article}
}
Kettner, M; Ramsthaler, F; Potente, S; Bockenheimer, A; Schmidt, P H; Schrodt, M
Blunt force impact to the head using a teeball bat: systematic comparison of physical and finite element modeling Journal Article
In: Forensic Science, Medicine & Pathology, vol. 10, no. 4, pp. 513–517, 2014.
Abstract | BibTeX | Tags: *Computer Simulation, *Forensic Pathology/mt [Methods], *HEAD injuries, *Models, *Skull Fractures/pa [Pathology], *Skull/pa [Pathology], *Sports Equipment, *Weapons, Anatomic, Biological, Biomechanical Phenomena, Closed/pa [Pathology], Equipment Design, finite element analysis, Humans, Skull/in [Injuries], violence, Wood, Young Adult
@article{Kettner2014,
title = {Blunt force impact to the head using a teeball bat: systematic comparison of physical and finite element modeling},
author = {Kettner, M and Ramsthaler, F and Potente, S and Bockenheimer, A and Schmidt, P H and Schrodt, M},
year = {2014},
date = {2014-01-01},
journal = {Forensic Science, Medicine \& Pathology},
volume = {10},
number = {4},
pages = {513--517},
abstract = {Blunt head trauma secondary to violent actions with various weapons is frequently a cause of injury in forensic casework; differing striking tools have varying degrees of injury capacity. The systematic approach used to examine a 19-year-old student who was beaten with a wooden teeball bat will be described. The assailant stopped beating the student when the teeball bat broke into two pieces. The surviving victim sustained bruises and a forehead laceration. The State's Attorney assigned a forensic expert to examine whether the forces exerted on the victim's head (leading to the fracture of the bat) were potentially life threatening (e.g. causing cranial bone fractures). Physical modeling was conducted using a pigskin-covered polyethylene end cap cushioned by cellulose that was connected to a piezoelectric force gauge. Experiments with teeball bats weighing 295-485 g demonstrated that 12-20 kN forces were necessary to cause a comparable bat fracture. In addition to physical testing, a computer-aided simulation was conducted, utilizing a finite-element (FE) method. In the FE approach, after selecting for wood properties, a virtual bat was swung against a hemisphere comprising two layers that represented bone and soft tissue. Employing this model, a 17.6 kN force was calculated, with the highest fracture probability points resembling the fracture patterns of the physically tested bats.},
keywords = {*Computer Simulation, *Forensic Pathology/mt [Methods], *HEAD injuries, *Models, *Skull Fractures/pa [Pathology], *Skull/pa [Pathology], *Sports Equipment, *Weapons, Anatomic, Biological, Biomechanical Phenomena, Closed/pa [Pathology], Equipment Design, finite element analysis, Humans, Skull/in [Injuries], violence, Wood, Young Adult},
pubstate = {published},
tppubtype = {article}
}
McIntosh, A S; Lai, A; Schilter, E
Bicycle helmets: head impact dynamics in helmeted and unhelmeted oblique impact tests Journal Article
In: Traffic Injury Prevention, vol. 14, no. 5, pp. 501–508, 2013.
Abstract | BibTeX | Tags: *Accidents, *Bicycling/in [Injuries], *Craniocerebral Trauma/et [Etiology], *Head Protective Devices/ut [Utilization], Acceleration, Biological, Biomechanical Phenomena, Computer simulation, Humans, Male, Manikins, Models, Traffic/sn [Statistics & Numerical Dat
@article{McIntosh2013,
title = {Bicycle helmets: head impact dynamics in helmeted and unhelmeted oblique impact tests},
author = {McIntosh, A S and Lai, A and Schilter, E},
year = {2013},
date = {2013-01-01},
journal = {Traffic Injury Prevention},
volume = {14},
number = {5},
pages = {501--508},
abstract = {OBJECTIVE: To assess the factors, including helmet use, that contribute to head linear and angular acceleration in bicycle crash simulation tests. METHOD: A series of laboratory tests was undertaken using an oblique impact rig. The impact rig included a drop assembly with a Hybrid III head and neck. The head struck a horizontally moving striker plate. Head linear and angular acceleration and striker plate force were measured. The Head Injury Criterion was derived. The following test parameters were varied: drop height to a maximum of 1.5 m, horizontal speed to a maximum of 25 km/h, helmet/no helmet, impact orientation/location, and restraint adjustment. Additional radial impacts were conducted on the same helmet models for comparison purposes. Descriptive statistics were derived and multiple regression was applied to examine the role of each parameter. RESULTS: Helmet use was the most significant factor in reducing the magnitude of all outcome variables. Linear acceleration and the Head Injury Criterion were influenced by the drop height, whereas angular acceleration tended to be influenced by the horizontal speed and impact orientation/location. The restraint adjustment influenced the outcome variables, with lower coefficients of variation observed with the tight restraint. CONCLUSIONS: The study reinforces the benefits of wearing a bicycle helmet in a crash. The study also demonstrates that helmets do not increase angular head acceleration. The study assists in establishing the need for an agreed-upon international oblique helmet test as well as the boundary conditions for oblique helmet testing.},
keywords = {*Accidents, *Bicycling/in [Injuries], *Craniocerebral Trauma/et [Etiology], *Head Protective Devices/ut [Utilization], Acceleration, Biological, Biomechanical Phenomena, Computer simulation, Humans, Male, Manikins, Models, Traffic/sn [Statistics \& Numerical Dat},
pubstate = {published},
tppubtype = {article}
}
Ivancic, P C
Neck injury response to direct head impact Journal Article
In: Accident Analysis & Prevention, vol. 50, pp. 323–329, 2013.
Abstract | BibTeX | Tags: *Accidents, *Neck Injuries/et [Etiology], *Neck Injuries/pp [Physiopathology], Acceleration, ANALYSIS of variance, Biomechanical Phenomena, Cadaver, Humans, Manikins, Rotation, Traffic, VIDEO recording
@article{Ivancic2013,
title = {Neck injury response to direct head impact},
author = {Ivancic, P C},
year = {2013},
date = {2013-01-01},
journal = {Accident Analysis \& Prevention},
volume = {50},
pages = {323--329},
abstract = {Previous in vivo studies have observed flexion of the upper or upper/middle cervical spine and extension at inferior spinal levels due to direct head impacts. These studies hypothesized that hyperflexion may contribute to injury of the upper or middle cervical spine during real-life head impact. Our objectives were to determine the cervical spine injury response to direct head impact, document injuries, and compare our results with previously reported in vivo data. Our model consisted of a human cadaver neck (n=6) mounted to the torso of a rear impact dummy and carrying a surrogate head. Rearward force was applied to the model's forehead using a cable and pulley system and free-falling mass of 3.6kg followed by 16.7kg. High-speed digital cameras tracked head, vertebral, and pelvic motions. Average peak spinal rotations observed during impact were statistically compared (P\<0.05) to physiological ranges obtained from intact flexibility tests. Peak head impact force was 249 and 504N for the 3.6 and 16.7kg free-falling masses, respectively. Occipital condyle loads reached 205.3N posterior shear, 331.4N compression, and 7.4Nm extension moment. We observed significant increases in intervertebral extension peaks above physiologic at C6/7 (26.3degree vs. 5.7degree) and C7/T1 (29.7degree vs. 4.6degree) and macroscopic ligamentous and osseous injuries at C6 through T1 due to the 504N impacts. Our results indicate that a rearward head shear force causes complex neck loads of posterior shear, compression, and extension moment sufficient to injure the lower cervical spine. Real-life neck injuries due to motor vehicle crashes, sports impacts, or falls are likely due to combined loads transferred to the neck by direct head impact and torso inertial loads. Copyright © 2012 Elsevier Ltd. All rights reserved.},
keywords = {*Accidents, *Neck Injuries/et [Etiology], *Neck Injuries/pp [Physiopathology], Acceleration, ANALYSIS of variance, Biomechanical Phenomena, Cadaver, Humans, Manikins, Rotation, Traffic, VIDEO recording},
pubstate = {published},
tppubtype = {article}
}
Estevan, I; Alvarez, O; Falco, C; Molina-Garcia, J; Castillo, I
Impact force and time analysis influenced by execution distance in a roundhouse kick to the head in taekwondo Journal Article
In: Journal of Strength & Conditioning Research, vol. 25, no. 10, pp. 2851–2856, 2011.
Abstract | BibTeX | Tags: *HEAD, *Martial Arts/ph [Physiology], *Task Performance and Analysis, adult, Biomechanical Phenomena, Humans, Male, Young Adult
@article{Estevan2011,
title = {Impact force and time analysis influenced by execution distance in a roundhouse kick to the head in taekwondo},
author = {Estevan, I and Alvarez, O and Falco, C and Molina-Garcia, J and Castillo, I},
year = {2011},
date = {2011-01-01},
journal = {Journal of Strength \& Conditioning Research},
volume = {25},
number = {10},
pages = {2851--2856},
abstract = {The execution distance is a tactic factor that affects mechanical performance and execution technique in taekwondo. This study analyzes the roundhouse kick to the head by comparing the maximum impact force, execution time, and impact time in 3 distances according to the athletes' competition level. It also analyzes the relationship between impact force and weight in each group. It examines whether the execution distance affects the maximum impact force, execution time, and impact time, in each level group or 2 different competition levels. Participants were 27 male taekwondo players (13 medallists and 14 nonmedallists). The medallists executed the roundhouse kick to the head with greater impact force and in a shorter execution time than did the nonmedallists when they kicked from any distance different to their combat distance. However, the results showed that the execution distance is influential in the execution time and impact time in the nonmedallist group. It is considered appropriate to orientate the high-level competitors to train for offensive actions from any distance similar to the long execution distance because it offers equally effectiveness and a greater security against the opponent. Also, practitioners should focus their training to improve time performance because it is more affected by distance than impact force.},
keywords = {*HEAD, *Martial Arts/ph [Physiology], *Task Performance and Analysis, adult, Biomechanical Phenomena, Humans, Male, Young Adult},
pubstate = {published},
tppubtype = {article}
}
Theobald, P; Whitelegg, L; Nokes, L D; Jones, M D
The predicted risk of head injury from fall-related impacts on to third-generation artificial turf and grass soccer surfaces: a comparative biomechanical analysis Journal Article
In: Sports Biomechanics, vol. 9, no. 1, pp. 29–37, 2010.
Abstract | BibTeX | Tags: *Athletic Injuries/et [Etiology], *Brain Injuries/et [Etiology], *Soccer/in [Injuries], Accidental Falls, Biomechanical Phenomena, Humans, Injury Severity Score, Poaceae, Risk
@article{Theobald2010,
title = {The predicted risk of head injury from fall-related impacts on to third-generation artificial turf and grass soccer surfaces: a comparative biomechanical analysis},
author = {Theobald, P and Whitelegg, L and Nokes, L D and Jones, M D},
year = {2010},
date = {2010-01-01},
journal = {Sports Biomechanics},
volume = {9},
number = {1},
pages = {29--37},
abstract = {The risk of soccer players sustaining mild traumatic brain injury (MTBI) following head impact with a playing surface is unclear. This study investigates MTBI by performing headform impact tests from varying heights onto a range of third-generation artificial turf surfaces. Each turf was prepared as per manufacturers specifications within a laboratory, before being tested immediately following installation and then again after a bedding-in period. Each turf was tested dry and when wetted to saturation. Data from the laboratory tests were compared to an in situ third-generation surface and a professional grass surface. The surface performance threshold was set at a head impact criterion (HIC) = 400, which equates to a 10% risk of the head impact causing MTBI. All six third-generation surfaces had a \> 10% risk of MTBI from a fall \> 0.77 m; the inferior surfaces required a fall from just 0.46 m to have a 10% MTBI risk. Wetting the artificial turf did not produce a statistically significant improvement (P \> 0.01). The in situ third-generation playing surface produced HIC values within the range of bedded-in experimental values. However, the natural turf pitch was the superior performer--necessitating fall heights exceeding those achievable during games to achieve HIC = 400.},
keywords = {*Athletic Injuries/et [Etiology], *Brain Injuries/et [Etiology], *Soccer/in [Injuries], Accidental Falls, Biomechanical Phenomena, Humans, Injury Severity Score, Poaceae, Risk},
pubstate = {published},
tppubtype = {article}
}
Depreitere, B; Van Lierde, C; Vander Sloten, J; Van der Perre, G; Van Audekercke, R; Plets, C; Goffin, J
Lateral head impacts and protection of the temporal area by bicycle safety helmets Journal Article
In: Journal of Trauma-Injury Infection & Critical Care, vol. 62, no. 6, pp. 1440–1445, 2007.
Abstract | BibTeX | Tags: *Bicycling, *HEAD injuries, *Head Protective Devices, *Skull Fractures, *Temporal Bone/in [Injuries], Athletic Injuries/pc [Prevention & Control], Biomechanical Phenomena, Cadaver, Closed/pc [Prevention & Control], Humans
@article{Depreitere2007,
title = {Lateral head impacts and protection of the temporal area by bicycle safety helmets},
author = {Depreitere, B and {Van Lierde}, C and {Vander Sloten}, J and {Van der Perre}, G and {Van Audekercke}, R and Plets, C and Goffin, J},
year = {2007},
date = {2007-01-01},
journal = {Journal of Trauma-Injury Infection \& Critical Care},
volume = {62},
number = {6},
pages = {1440--1445},
abstract = {BACKGROUND: The protective effectiveness of bicycle helmets has been demonstrated in several epidemiologic studies. However, the temple region is only minimally covered by most helmet models. Impact tests were performed on human cadavers to investigate whether current bicycle helmets are capable of preventing direct contact on the temporal area in side impacts. METHODS: Lateral head impacts, corresponding to a force load of 15,000 N on an nonhelmeted head, were applied on 11 helmeted cadavers by a steel pendulum with a flat impact surface, and the contact between the impactor plate and the temporal and zygomatic area was investigated by means of paint transfer. In eight tests, a common design bicycle helmet was used, whereas in three tests the helmets provided larger temporal coverage (temporal helmet edge \<10 mm above Frankfort plane). The skulls were inspected for fractures. RESULTS: In seven of the eight tests with common design bicycle helmets, contact had occurred and in one of these a skull fracture was seen. The helmets with a larger temporal coverage consistently prevented such contact loading. CONCLUSIONS: The common designs of commercially available bicycle helmets do not prevent direct contact loading on the temporal and zygomatic arch region and this contact loading is potentially harmful. The present preliminary study strongly questions the effectiveness of these helmets in providing accurate protection of the temporal and zygomatic area.},
keywords = {*Bicycling, *HEAD injuries, *Head Protective Devices, *Skull Fractures, *Temporal Bone/in [Injuries], Athletic Injuries/pc [Prevention \& Control], Biomechanical Phenomena, Cadaver, Closed/pc [Prevention \& Control], Humans},
pubstate = {published},
tppubtype = {article}
}
Davis, A E
Mechanisms of traumatic brain injury: biomechanical, structural and cellular considerations Journal Article
In: Critical Care Nursing Quarterly, vol. 23, no. 3, pp. 1–13, 2000.
Abstract | BibTeX | Tags: *Brain Injuries/pa [Pathology], *Brain Injuries/pp [Physiopathology], Biomechanical Phenomena, Brain Injuries/cl [Classification], Brain Injuries/co [Complications], Brain/me [Metabolism], Brain/pa [Pathology], Humans, intracranial hemorrhage, Neurons/me [Metabolism], Neurons/pa [Pathology], Nonpenetrating/pa [Pathology], Nonpenetrating/pp [Physiopathology], Skull Fractures/pa [Pathology], Skull Fractures/pp [Physiopathology], Traumatic/pa [Pathology], Traumatic/pp [Physiopatho, Wounds
@article{Davis2000,
title = {Mechanisms of traumatic brain injury: biomechanical, structural and cellular considerations},
author = {Davis, A E},
year = {2000},
date = {2000-01-01},
journal = {Critical Care Nursing Quarterly},
volume = {23},
number = {3},
pages = {1--13},
abstract = {Traumatic brain injury (TBI) is a public health problem of great concern, because it affects more than 2 million individuals each year. TBI occurs as a result of motor vehicle crashes, falls, and sports-related events. Biomechanical mechanisms occurring at the time of the injury initiate primary and secondary injuries that evolve over several days. In this article the relationship between an blunt injury event and the subsequent damage produced is addressed. Mechanisms of brain injury from biomechanics to cellular pathobiology are presented. Primary and secondary injuries are differentiated, and specific focal and diffuse clinical syndromes are described. Cellular mechanisms responsible for injury are also addressed, because they provide the unifying concepts across the many clinical syndromes so often discussed separately in reviews of traumatic brain injury. [References: 26]},
keywords = {*Brain Injuries/pa [Pathology], *Brain Injuries/pp [Physiopathology], Biomechanical Phenomena, Brain Injuries/cl [Classification], Brain Injuries/co [Complications], Brain/me [Metabolism], Brain/pa [Pathology], Humans, intracranial hemorrhage, Neurons/me [Metabolism], Neurons/pa [Pathology], Nonpenetrating/pa [Pathology], Nonpenetrating/pp [Physiopathology], Skull Fractures/pa [Pathology], Skull Fractures/pp [Physiopathology], Traumatic/pa [Pathology], Traumatic/pp [Physiopatho, Wounds},
pubstate = {published},
tppubtype = {article}
}
Perry, C E; Buhrman, J R
Effect of helmet inertial properties on head and neck response during +Gz impact accelerations Journal Article
In: Journal of Gravitational Physiology: a Journal of the International Society for Gravitational Physiology, vol. 2, no. 1, pp. P88–91, 1995.
Abstract | BibTeX | Tags: *Acceleration/ae [Adverse Effects], *Head Protective Devices, *Neck/ph [Physiology], Aircraft, Aviation, Biomechanical Phenomena, Computer simulation, Equipment Design, Head Movements, Humans, Military personnel, Motion, Neck Injuries, SAFETY
@article{Perry1995,
title = {Effect of helmet inertial properties on head and neck response during +Gz impact accelerations},
author = {Perry, C E and Buhrman, J R},
year = {1995},
date = {1995-01-01},
journal = {Journal of Gravitational Physiology: a Journal of the International Society for Gravitational Physiology},
volume = {2},
number = {1},
pages = {P88--91},
abstract = {The objective of the test program was to study the effect of parametric changes in helmet inertial properties on the biodynamic response of human volunteers subjected to +Gz impact accelerations. Test data was used to drive a computer model (DYNAMAN) to estimate the loads and torques in the neck during impact. Currently, only seven of eleven test cells with variations in the inertial properties of the helmet along the x-axis of the head have been analyzed. Preliminary data analysis indicates that the biodynamic response of the head under the tested conditions is slightly more sensitive to the moment of inertia of the helmet than its weight alone even though both variables showed a general trend for the head accelerations (linear and angular) to increase. It has been shown that the model can give good estimates of the compression loads in the neck, but that the torque estimates will be low, possibly by a factor of three. Further refinements of the neck joint parameters in the model will be required in order to increase the motion of the head segment during impact acceleration and will be done prior to completing the remaining test cell analysis. Finally, all the test data will be evaluated to determine if the current interim head criteria require modification.},
keywords = {*Acceleration/ae [Adverse Effects], *Head Protective Devices, *Neck/ph [Physiology], Aircraft, Aviation, Biomechanical Phenomena, Computer simulation, Equipment Design, Head Movements, Humans, Military personnel, Motion, Neck Injuries, SAFETY},
pubstate = {published},
tppubtype = {article}
}