Terwilliger, V K; Pratson, L; Vaughan, C G; Gioia, G A
Additional Post-Concussion Impact Exposure May Affect Recovery in Adolescent Athletes Journal Article
In: Journal of Neurotrauma, vol. 33, no. 8, pp. 761–765, 2016.
Abstract | Links | BibTeX | Tags: Adolescent, Article, athlete, Athletes, brain concussion, Brain Injury, clinical article, Concussion, controlled study, CONVALESCENCE, Female, human, Male, mTBI, Parent, postconcussion syndrome, retrospective study, risk factor, sport injury
@article{Terwilliger2016,
title = {Additional Post-Concussion Impact Exposure May Affect Recovery in Adolescent Athletes},
author = {Terwilliger, V K and Pratson, L and Vaughan, C G and Gioia, G A},
doi = {10.1089/neu.2015.4082},
year = {2016},
date = {2016-01-01},
journal = {Journal of Neurotrauma},
volume = {33},
number = {8},
pages = {761--765},
abstract = {Repeat concussion has been associated with risk for prolonged and pronounced clinical recovery in athletes. In this study of adolescent athletes, we examined whether an additional head impact within 24 h of a sports-related concussion (SRC) is associated with higher symptom burden and prolonged clinical recovery compared with a single-injury group. Forty-two student-athletes (52% male, mean age = 14.9 years) diagnosed with an SRC in a concussion clinic were selected for this study: (1) 21 athletes who sustained an additional significant head impact within 24 h of the initial injury (additional-impact group); (2) 21 single-injury athletes, age and gender matched, who sustained only one discrete concussive blow to the head (single-injury group). Groups did not differ on initial injury characteristics or pre-injury risk factors. The effect of injury status (single-vs. additional-impact) was examined on athlete-and parent-reported symptom burden (at first clinic visit) and length of recovery (LOR). Higher symptom burden was reported by the athletes and parents in the additional-impact group at the time of first visit. The additional-impact group also had a significantly longer LOR compared with the single-injury group. These findings provide preliminary, hypothesis-generating evidence for the importance of immediate removal from play following an SRC to protect athletes from re-injury, which may worsen symptoms and prolong recovery. The retrospective study design from a specialized clinical sample points to the need for future prospective studies of the relationship between single-and additional-impact injuries on symptom burden and LOR. © 2016 Mary Ann Liebert, Inc.},
keywords = {Adolescent, Article, athlete, Athletes, brain concussion, Brain Injury, clinical article, Concussion, controlled study, CONVALESCENCE, Female, human, Male, mTBI, Parent, postconcussion syndrome, retrospective study, risk factor, sport injury},
pubstate = {published},
tppubtype = {article}
}
Abaji, J P; Curnier, D; Moore, R D; Ellemberg, D
Persisting effects of concussion on heart rate variability during physical exertion Journal Article
In: Journal of Neurotrauma, vol. 33, no. 9, pp. 811–817, 2016.
Abstract | Links | BibTeX | Tags: adult, Article, athlete, brain concussion, cardiac autonomic modulation, clinical article, Concussion, controlled study, cross-sectional study, electrocardiogram, exercise, hand grip, heart rate variability, human, isometric hand grip contraction, Male, muscle isometric contraction, PHYSICAL ACTIVITY
@article{Abaji2016,
title = {Persisting effects of concussion on heart rate variability during physical exertion},
author = {Abaji, J P and Curnier, D and Moore, R D and Ellemberg, D},
doi = {10.1089/neu.2015.3989},
year = {2016},
date = {2016-01-01},
journal = {Journal of Neurotrauma},
volume = {33},
number = {9},
pages = {811--817},
abstract = {The purpose of this study was to evaluate cardiac autonomic modulation in university athletes during the post-acute to late phase (mean, 95 days ±63) of injury at rest and during physical exertion. We also sought to evaluate the effect of time since injury and number of injuries on heart rate variability (HRV). We hypothesized that physical exertion would reveal persisting modifications in HRV following a concussion. We included, in a cross-sectional design, athletes who sustained a concussion and matched controls. Concussions were identified by a medical doctor using established criteria. Twelve male concussed and 12 control athletes took part in the study. Control participants were teammates who were chosen to match the concussed athletes with regard to their height, weight, education, and age. The beat-to-beat electrocardiogram intervals of the participants were measured at rest and during physical exertion (isometric hand grip contraction; IHGC), which was sustained for 3 minutes at 30% of the participants' maximum. Linear and nonlinear parameters of HRV were calculated. The ratio between low and high frequency (LF/HF) bands was calculated to assess the sympathovagal balance. During the IHGC, but not at rest, concussed athletes presented significantly lower power in HF bands, leading to a significantly higher LF/HF ratio (p ≤ 0.05). Thus, asymptomatic athletes still may exhibit modifications in cardiac autonomic modulation weeks to months following injury. These modifications may only become apparent during physical exertion. Monitoring HRV may aid diagnosis and provide insight about safe return to play. © Mary Ann Liebert, Inc. 2016.},
keywords = {adult, Article, athlete, brain concussion, cardiac autonomic modulation, clinical article, Concussion, controlled study, cross-sectional study, electrocardiogram, exercise, hand grip, heart rate variability, human, isometric hand grip contraction, Male, muscle isometric contraction, PHYSICAL ACTIVITY},
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}
}
Vassilyadi, M; Macartney, G; Barrowman, N; Anderson, P; Dube, K
Symptom experience and quality of life in children after sport-related head injuries: A cross-sectional study Journal Article
In: Pediatric Neurosurgery, vol. 50, no. 4, pp. 196–203, 2015.
Abstract | Links | BibTeX | Tags: Adolescent, adult, affect, Article, Athletic Injuries, behavior disorder, brain concussion, Child, clinical article, clinical assessment, cognitive defect, Cognitive Efficiency Index, complication, Concussion, Concussion Symptom Scale, controlled study, Craniocerebral Trauma, Cross-Sectional Studies, cross-sectional study, fatigue, Female, head injury, headache, human, Humans, Immediate Postconcussion Assessment and Cognitive, Likert scale, Male, memory disorder, mild traumatic brain injury, neuropsychological test, noise, Paediatric patients, Pediatric Quality of Life Inventory, postconcussion syndrome, priority journal, psychology, quality of life, rating scale, scoring system, Sport, sport injury, Sports, symptom, time factor, Time Factors, traumatic brain injury, trends
@article{Vassilyadi2015,
title = {Symptom experience and quality of life in children after sport-related head injuries: A cross-sectional study},
author = {Vassilyadi, M and Macartney, G and Barrowman, N and Anderson, P and Dube, K},
doi = {10.1159/000431232},
year = {2015},
date = {2015-01-01},
journal = {Pediatric Neurosurgery},
volume = {50},
number = {4},
pages = {196--203},
abstract = {Background: Sports are a major cause of concussions, and little is known about the symptom experience and health-related quality of life (HRQL) in children who remain symptomatic for over 3 months following such head injuries. Methods: A cross-sectional study of children aged 10-18 years was performed who were referred to the Neurosurgery Clinic at our centre following a head injury. Symptom experience was measured using the modified Concussion Symptom Scale, and HRQL was measured using the Pediatric Quality of Life Inventory (PedsQL). The Immediate Postconcussion Assessment and Cognitive Test (ImPACT) was administered to assess neurocognitive and neurobehavioural sequelae. Results: Symptoms with the highest mean symptom scores on a Likert scale of 0-6 in 35 children at the time of assessment included headaches (3.1), poor concentration (2.7), memory problems (2.1), fatigue (2.1) and sensitivity to noise (2.0). Compared with normative data, children in this study had ImPACT summary scores between the 28th and 38th percentiles and a comparably low Cognitive Efficiency Index score. Mean scores for females were consistently statistically significantly lower (p \< 0.05) than for males across all of the HRQL domains. Trouble falling asleep and memory problems explained 62% of the variance in the PedsQL total scores. Conclusions: Children continue to experience many symptoms at least 3 months following sport-related head injuries that significantly impact their HRQL and neurocognitive abilities. © 2015 S. Karger AG, Basel.},
keywords = {Adolescent, adult, affect, Article, Athletic Injuries, behavior disorder, brain concussion, Child, clinical article, clinical assessment, cognitive defect, Cognitive Efficiency Index, complication, Concussion, Concussion Symptom Scale, controlled study, Craniocerebral Trauma, Cross-Sectional Studies, cross-sectional study, fatigue, Female, head injury, headache, human, Humans, Immediate Postconcussion Assessment and Cognitive, Likert scale, Male, memory disorder, mild traumatic brain injury, neuropsychological test, noise, Paediatric patients, Pediatric Quality of Life Inventory, postconcussion syndrome, priority journal, psychology, quality of life, rating scale, scoring system, Sport, sport injury, Sports, symptom, time factor, Time Factors, traumatic brain injury, trends},
pubstate = {published},
tppubtype = {article}
}
Patton, D A; McIntosh, A S; Kleiven, S
In: Journal of Applied Biomechanics, vol. 31, no. 4, pp. 264–268, 2015.
Abstract | Links | BibTeX | Tags: Article, Biomechanics, brain, Brain Injury, brain region, clinical article, Concussion, corpus callosum, Damage detection, evaluation study, finite element analysis, Finite element head models, Finite element method, Finite element simulations, football, gray matter, Head Injuries, head injury, human, Intra-cranial pressure, intracranial pressure, investigative procedures, Maximum principal strain, mesencephalon, Modeling, Models, Numerical reconstruction, Qualitative observations, Sport, sport injury, Sports, Strain and strain rates, Strain rate, Stress, thalamus, Tissue, tissue level
@article{Patton2015,
title = {The biomechanical determinants of concussion: Finite element simulations to investigate tissue-level predictors of injury during sporting impacts to the unprotected head},
author = {Patton, D A and McIntosh, A S and Kleiven, S},
doi = {10.1123/jab.2014-0223},
year = {2015},
date = {2015-01-01},
journal = {Journal of Applied Biomechanics},
volume = {31},
number = {4},
pages = {264--268},
abstract = {Biomechanical studies of concussions have progressed from qualitative observations of head impacts to physical and numerical reconstructions, direct impact measurements, and finite element analyses. Supplementary to a previous study, which investigated maximum principal strain, the current study used a detailed finite element head model to simulate unhelmeted concussion and no-injury head impacts and evaluate the effectiveness of various tissue-level brain injury predictors: strain rate, product of strain and strain rate, cumulative strain damage measure, von Mises stress, and intracranial pressure. Von Mises stress was found to be the most effective predictor of concussion. It was also found that the thalamus and corpus callosum were brain regions with strong associations with concussion. Tentative tolerance limits for tissue-level predictors were proposed in an attempt to broaden the understanding of unhelmeted concussions. For the thalamus, tolerance limits were proposed for a 50% likelihood of concussion: 2.24 kPa, 24.0 s-1, and 2.49 s-1 for von Mises stress, strain rate, and the product of strain and strain rate, respectively. For the corpus callosum, tolerance limits were proposed for a 50% likelihood of concussion: 3.51 kPa, 25.1 s-1, and 2.76 s-1 for von Mises stress, strain rate, and the product of strain and strain rate, respectively. © 2015 Human Kinetics, Inc.},
keywords = {Article, Biomechanics, brain, Brain Injury, brain region, clinical article, Concussion, corpus callosum, Damage detection, evaluation study, finite element analysis, Finite element head models, Finite element method, Finite element simulations, football, gray matter, Head Injuries, head injury, human, Intra-cranial pressure, intracranial pressure, investigative procedures, Maximum principal strain, mesencephalon, Modeling, Models, Numerical reconstruction, Qualitative observations, Sport, sport injury, Sports, Strain and strain rates, Strain rate, Stress, thalamus, Tissue, tissue level},
pubstate = {published},
tppubtype = {article}
}
Gardner, A J; Iverson, G L; Quinn, T N; Makdissi, M; Levi, C R; Shultz, S R; Wright, D K; Stanwell, P
A preliminary video analysis of concussion in the National Rugby League Journal Article
In: Brain Injury, vol. 29, no. 10, pp. 1182–1185, 2015.
Abstract | Links | BibTeX | Tags: Article, athlete, Athletes, brain concussion, case study, clinical article, Concussion, descriptive research, EPIDEMIOLOGY, human, Incidence, Injury surveillance, observational study, rugby, sport injury, unconsciousness, videorecording
@article{Gardner2015b,
title = {A preliminary video analysis of concussion in the National Rugby League},
author = {Gardner, A J and Iverson, G L and Quinn, T N and Makdissi, M and Levi, C R and Shultz, S R and Wright, D K and Stanwell, P},
doi = {10.3109/02699052.2015.1034179},
year = {2015},
date = {2015-01-01},
journal = {Brain Injury},
volume = {29},
number = {10},
pages = {1182--1185},
abstract = {Primary objective: To conduct the first video analysis of concussion in the Australian National Rugby League (NRL) and describe player and injury characteristics, situational factors and time to return to play.Research design: Descriptive, observational case series.Methods and procedures: Video analysis of 20 medically diagnosed concussions for three consenting clubs during the 2013 NRL season.Main outcome and results: Most concussions (83%) occurred during a high tackle, and all injured ball carriers were hit high. Loss of consciousness was observed in 30% of cases. Common observable signs of injury included clutching of the head, balance problems or wobbly legs and a blank or vacant state. There were no post-concussive seizures. All players with loss of consciousness were removed from play. However, only half of the total sample was removed from play and one athlete who was removed returned to play in the same match. Of the players who were removed from play, the large majority returned the following week. Illegal play accounted for 25% of all concussions.Conclusions: Video analysis may be a useful method to study the incidence, mechanism and management of concussion in sports such as Rugby League. Future studies may include larger numbers to validate this preliminary data and may also investigate other levels of play and age ranges. © 2015 Taylor and Francis Group, LLC.},
keywords = {Article, athlete, Athletes, brain concussion, case study, clinical article, Concussion, descriptive research, EPIDEMIOLOGY, human, Incidence, Injury surveillance, observational study, rugby, sport injury, unconsciousness, videorecording},
pubstate = {published},
tppubtype = {article}
}
Dretsch, M N; Kelly, M P; Coldren, R L; Parish, R V; Russell, M L
In: Journal of Neurotrauma, vol. 32, no. 16, pp. 1217–1222, 2015.
Abstract | Links | BibTeX | Tags: 2003-2011, acute disease, Adolescent, adult, amnesia, ANAM, Article, assessment of humans, Automated Neuropsychological Assessment Metrics, Blast injuries, blast injury, blunt trauma, brain concussion, clinical article, cognition, Cognition Disorders, cognitive screening, comparative study, complication, concussion mechanism, Demography, deployment, Female, follow up, health status, human, Humans, Iraq War, Male, middle aged, Military, Military Acute Concussion Evaluation, Military personnel, neuropsychological test, Neuropsychological Tests, soldier, unconsciousness, UNITED States, War, Young Adult
@article{Dretsch2015a,
title = {No Significant Acute and Subacute Differences between Blast and Blunt Concussions across Multiple Neurocognitive Measures and Symptoms in Deployed Soldiers},
author = {Dretsch, M N and Kelly, M P and Coldren, R L and Parish, R V and Russell, M L},
doi = {10.1089/neu.2014.3637},
year = {2015},
date = {2015-01-01},
journal = {Journal of Neurotrauma},
volume = {32},
number = {16},
pages = {1217--1222},
abstract = {Seventy-one deployed U.S. Army soldiers who presented for concussion care due to either blast or blunt mechanisms within 72 h of injury were assessed using the Military Acute Concussion Evaluation, the Automated Neuropsychological Assessment Metrics (ANAM), traditional neuropsychological tests, and health status questionnaires. Follow-up ANAM testing was performed 10 d after initial testing (±5 d). Twenty-one soldiers were excluded: two for poor effort and 19 who had combined blast/blunt injuries. Of the remaining 50 male participants, 34 had blast injuries and 16 had blunt injuries. There were no statistically significant differences between blast injury and blunt injury participants in demographic, physical, or psychological health factors, concussive symptoms, or automated and traditional neurocognitive testing scores within 72 h post-injury. In addition, follow-up ANAM scores up to 15 d post-injury were not significantly different (available on 21 blast-injured and 13 blunt-injured subjects). Pre-injury baseline ANAM scores were compared where available, and revealed no statistically significant differences between 22 blast injury and eight blunt injury participants. These findings suggest there are no significant differences between mechanisms of injury during both the acute and subacute periods in neurobehavioral concussion sequelae while deployed in a combat environment. The current study supports the use of sports/mechanical concussion models for early concussion management in the deployed setting and exploration of variability in potential long-term outcomes. © Copyright 2015, Mary Ann Liebert, Inc.},
keywords = {2003-2011, acute disease, Adolescent, adult, amnesia, ANAM, Article, assessment of humans, Automated Neuropsychological Assessment Metrics, Blast injuries, blast injury, blunt trauma, brain concussion, clinical article, cognition, Cognition Disorders, cognitive screening, comparative study, complication, concussion mechanism, Demography, deployment, Female, follow up, health status, human, Humans, Iraq War, Male, middle aged, Military, Military Acute Concussion Evaluation, Military personnel, neuropsychological test, Neuropsychological Tests, soldier, unconsciousness, UNITED States, War, Young Adult},
pubstate = {published},
tppubtype = {article}
}
Sikoglu, E M; Liso Navarro, A A; Czerniak, S M; McCafferty, J; Eisenstock, J; Stevenson, J H; King, J A; Moore, C M
Effects of Recent Concussion on Brain Bioenergetics: A Phosphorus-31 Magnetic Resonance Spectroscopy Study Journal Article
In: Cognitive and Behavioral Neurology, vol. 28, no. 4, pp. 181–187, 2015.
Abstract | Links | BibTeX | Tags: Adolescent, adult, Article, athlete, Athletic Injuries, biochemical analysis, bioenergy, brain concussion, clinical article, cognition, college, Concussion, energy consumption, Energy Metabolism, Female, high energy phosphate, human, Humans, Longitudinal studies, longitudinal study, Magnetic Resonance Spectroscopy, Male, metabolism, MR spectroscopy (phosphorus-31), neuroimaging, NTP, NUCLEAR magnetic resonance spectroscopy, nucleoside, nucleoside triphosphate, Nucleosides, Pathophysiology, phosphate, Phosphates, phosphorus, Phosphorus Isotopes, phosphorus nuclear magnetic resonance, PHYSIOLOGY, Prefrontal Cortex, priority journal, procedures, sport injury, Universities, university, Young Adult
@article{Sikoglu2015,
title = {Effects of Recent Concussion on Brain Bioenergetics: A Phosphorus-31 Magnetic Resonance Spectroscopy Study},
author = {Sikoglu, E M and {Liso Navarro}, A A and Czerniak, S M and McCafferty, J and Eisenstock, J and Stevenson, J H and King, J A and Moore, C M},
doi = {10.1097/WNN.0000000000000076},
year = {2015},
date = {2015-01-01},
journal = {Cognitive and Behavioral Neurology},
volume = {28},
number = {4},
pages = {181--187},
abstract = {Background: Although clinical evaluations and neurocognitive assessments are commonly used to evaluate the extent of and recovery from concussion, brain bioenergetics could provide a more quantitative marker. The neurometabolic response to a concussion is thought to increase neuronal energy consumption and thus the demand for nucleoside triphosphate (NTP). Objective: We investigated the possible disruption in high-energy metabolism within the prefrontal cortex of college athletes who had either had a concussion within the past 6 months (n=14) or had never had a concussion (n=13). We hypothesized that concussed athletes would have imbalanced brain bioenergetics resulting from increased NTP consumption, and these biochemical changes would correspond to impaired cognitive abilities. Methods: We used phosphorus-31 magnetic resonance spectroscopy to quantify high-energy phosphates. We performed the neuroimaging in conjunction with neurocognitive assessments targeting prefrontal cortex-mediated tasks. Results: Our results revealed significantly lower $gamma$-NTP levels in the athletes after concussion. Although the concussed and non-concussed participants performed similarly in neurocognitive assessments, lower levels of $gamma$-NTP were associated with worse scores on neurocognitive tasks. Conclusions: Our results support the concept of increased energy demand in the prefrontal cortex of a concussed brain, and we found that while neurocognitive assessments appear normal, brain energetics may be abnormal. A longitudinal study could help establish brain NTP levels as a biomarker to aid in diagnosis and to assess recovery in concussed patients. © 2015 Wolters Kluwer Health, Inc.},
keywords = {Adolescent, adult, Article, athlete, Athletic Injuries, biochemical analysis, bioenergy, brain concussion, clinical article, cognition, college, Concussion, energy consumption, Energy Metabolism, Female, high energy phosphate, human, Humans, Longitudinal studies, longitudinal study, Magnetic Resonance Spectroscopy, Male, metabolism, MR spectroscopy (phosphorus-31), neuroimaging, NTP, NUCLEAR magnetic resonance spectroscopy, nucleoside, nucleoside triphosphate, Nucleosides, Pathophysiology, phosphate, Phosphates, phosphorus, Phosphorus Isotopes, phosphorus nuclear magnetic resonance, PHYSIOLOGY, Prefrontal Cortex, priority journal, procedures, sport injury, Universities, university, Young Adult},
pubstate = {published},
tppubtype = {article}
}
Mayer, A R; Ling, J M; Dodd, A B; Gasparovic, C; Klimaj, S D; Meier, T B
A Longitudinal Assessment of Structural and Chemical Alterations in Mixed Martial Arts Fighters Journal Article
In: Journal of Neurotrauma, vol. 32, no. 22, pp. 1759–1767, 2015.
Abstract | Links | BibTeX | Tags: Adolescent, adult, Article, biological marker, Biomarkers, BRAIN chemistry, brain concussion, brain cortex, brain size, Cerebral Cortex, CHOLINE, clinical article, cognition, Concussion, controlled study, cortical thickness (brain), creatine, executive function, Female, follow up, Follow-Up Studies, frontal gyrus, glutamic acid, glutamine, human, Humans, Injuries, inositol, Longitudinal, Longitudinal studies, longitudinal study, Magnetic Resonance Imaging, Male, martial art, Martial Arts, Memory, middle aged, mixed martial art, n acetylaspartic acid, neuropsychological test, Neuropsychological Tests, nuclear magnetic resonance imaging, NUCLEAR magnetic resonance spectroscopy, occipital cortex, pathology, posterior cingulate, psychology, repetitive injury, Spectroscopy, volumetrics, white matter, Young Adult
@article{Mayer2015b,
title = {A Longitudinal Assessment of Structural and Chemical Alterations in Mixed Martial Arts Fighters},
author = {Mayer, A R and Ling, J M and Dodd, A B and Gasparovic, C and Klimaj, S D and Meier, T B},
doi = {10.1089/neu.2014.3833},
year = {2015},
date = {2015-01-01},
journal = {Journal of Neurotrauma},
volume = {32},
number = {22},
pages = {1759--1767},
abstract = {Growing evidence suggests that temporally proximal acute concussions and repetitive subconcussive head injuries may lead to long-term neurological deficits. However, the underlying mechanisms of injury and their relative time-scales are not well documented in human injury models. The current study therefore investigated whether biomarkers of brain chemistry (magnetic resonance [MR] spectroscopy: N-acetylaspartate [NAA], combined glutamate and glutamine [Glx], total creatine [Cre], choline compounds [Cho], and myo-inositol [mI]) and structure (cortical thickness, white matter [WM]/subcortical volume) differed between mixed martial artists (MMA; n = 13) and matched healthy controls (HC) without a history of contact sport participation (HC; n = 14). A subset of participants (MMA = 9; HC = 10) returned for follow-up visits, with MMA (n = 3) with clinician-documented acute concussions also scanned serially. As expected, MMA self-reported a higher incidence of previous concussions and significantly more cognitive symptoms during prior concussion recovery. Fighters also exhibited reduced memory and processing speed relative to controls on neuropsychological testing coupled with cortical thinning in the left posterior cingulate gyrus and right occipital cortex at baseline assessment. Over a 1-year follow-up period, MMA experienced a significant decrease in both WM volume and NAA concentration, as well as relative thinning in the left middle and superior frontal gyri. These longitudinal changes did not correlate with self-reported metrics of injury (i.e., fight diary). In contrast, HC did not exhibit significant longitudinal changes over a 4-month follow-up period (p \> 0.05). Collectively, current results provide preliminary evidence of progressive changes in brain chemistry and structure over a relatively short time period in individuals with high exposure to repetitive head hits. These findings require replication in independent samples. © Mary Ann Liebert, Inc. 2015.},
keywords = {Adolescent, adult, Article, biological marker, Biomarkers, BRAIN chemistry, brain concussion, brain cortex, brain size, Cerebral Cortex, CHOLINE, clinical article, cognition, Concussion, controlled study, cortical thickness (brain), creatine, executive function, Female, follow up, Follow-Up Studies, frontal gyrus, glutamic acid, glutamine, human, Humans, Injuries, inositol, Longitudinal, Longitudinal studies, longitudinal study, Magnetic Resonance Imaging, Male, martial art, Martial Arts, Memory, middle aged, mixed martial art, n acetylaspartic acid, neuropsychological test, Neuropsychological Tests, nuclear magnetic resonance imaging, NUCLEAR magnetic resonance spectroscopy, occipital cortex, pathology, posterior cingulate, psychology, repetitive injury, Spectroscopy, volumetrics, white matter, Young Adult},
pubstate = {published},
tppubtype = {article}
}
Terwilliger, V K; Pratson, L; Vaughan, C G; Gioia, G A
Additional Post-Concussion Impact Exposure May Affect Recovery in Adolescent Athletes Journal Article
In: Journal of Neurotrauma, vol. 33, no. 8, pp. 761–765, 2016.
@article{Terwilliger2016,
title = {Additional Post-Concussion Impact Exposure May Affect Recovery in Adolescent Athletes},
author = {Terwilliger, V K and Pratson, L and Vaughan, C G and Gioia, G A},
doi = {10.1089/neu.2015.4082},
year = {2016},
date = {2016-01-01},
journal = {Journal of Neurotrauma},
volume = {33},
number = {8},
pages = {761--765},
abstract = {Repeat concussion has been associated with risk for prolonged and pronounced clinical recovery in athletes. In this study of adolescent athletes, we examined whether an additional head impact within 24 h of a sports-related concussion (SRC) is associated with higher symptom burden and prolonged clinical recovery compared with a single-injury group. Forty-two student-athletes (52% male, mean age = 14.9 years) diagnosed with an SRC in a concussion clinic were selected for this study: (1) 21 athletes who sustained an additional significant head impact within 24 h of the initial injury (additional-impact group); (2) 21 single-injury athletes, age and gender matched, who sustained only one discrete concussive blow to the head (single-injury group). Groups did not differ on initial injury characteristics or pre-injury risk factors. The effect of injury status (single-vs. additional-impact) was examined on athlete-and parent-reported symptom burden (at first clinic visit) and length of recovery (LOR). Higher symptom burden was reported by the athletes and parents in the additional-impact group at the time of first visit. The additional-impact group also had a significantly longer LOR compared with the single-injury group. These findings provide preliminary, hypothesis-generating evidence for the importance of immediate removal from play following an SRC to protect athletes from re-injury, which may worsen symptoms and prolong recovery. The retrospective study design from a specialized clinical sample points to the need for future prospective studies of the relationship between single-and additional-impact injuries on symptom burden and LOR. © 2016 Mary Ann Liebert, Inc.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Abaji, J P; Curnier, D; Moore, R D; Ellemberg, D
Persisting effects of concussion on heart rate variability during physical exertion Journal Article
In: Journal of Neurotrauma, vol. 33, no. 9, pp. 811–817, 2016.
@article{Abaji2016,
title = {Persisting effects of concussion on heart rate variability during physical exertion},
author = {Abaji, J P and Curnier, D and Moore, R D and Ellemberg, D},
doi = {10.1089/neu.2015.3989},
year = {2016},
date = {2016-01-01},
journal = {Journal of Neurotrauma},
volume = {33},
number = {9},
pages = {811--817},
abstract = {The purpose of this study was to evaluate cardiac autonomic modulation in university athletes during the post-acute to late phase (mean, 95 days ±63) of injury at rest and during physical exertion. We also sought to evaluate the effect of time since injury and number of injuries on heart rate variability (HRV). We hypothesized that physical exertion would reveal persisting modifications in HRV following a concussion. We included, in a cross-sectional design, athletes who sustained a concussion and matched controls. Concussions were identified by a medical doctor using established criteria. Twelve male concussed and 12 control athletes took part in the study. Control participants were teammates who were chosen to match the concussed athletes with regard to their height, weight, education, and age. The beat-to-beat electrocardiogram intervals of the participants were measured at rest and during physical exertion (isometric hand grip contraction; IHGC), which was sustained for 3 minutes at 30% of the participants' maximum. Linear and nonlinear parameters of HRV were calculated. The ratio between low and high frequency (LF/HF) bands was calculated to assess the sympathovagal balance. During the IHGC, but not at rest, concussed athletes presented significantly lower power in HF bands, leading to a significantly higher LF/HF ratio (p ≤ 0.05). Thus, asymptomatic athletes still may exhibit modifications in cardiac autonomic modulation weeks to months following injury. These modifications may only become apparent during physical exertion. Monitoring HRV may aid diagnosis and provide insight about safe return to play. © Mary Ann Liebert, Inc. 2016.},
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}
}
Vassilyadi, M; Macartney, G; Barrowman, N; Anderson, P; Dube, K
Symptom experience and quality of life in children after sport-related head injuries: A cross-sectional study Journal Article
In: Pediatric Neurosurgery, vol. 50, no. 4, pp. 196–203, 2015.
@article{Vassilyadi2015,
title = {Symptom experience and quality of life in children after sport-related head injuries: A cross-sectional study},
author = {Vassilyadi, M and Macartney, G and Barrowman, N and Anderson, P and Dube, K},
doi = {10.1159/000431232},
year = {2015},
date = {2015-01-01},
journal = {Pediatric Neurosurgery},
volume = {50},
number = {4},
pages = {196--203},
abstract = {Background: Sports are a major cause of concussions, and little is known about the symptom experience and health-related quality of life (HRQL) in children who remain symptomatic for over 3 months following such head injuries. Methods: A cross-sectional study of children aged 10-18 years was performed who were referred to the Neurosurgery Clinic at our centre following a head injury. Symptom experience was measured using the modified Concussion Symptom Scale, and HRQL was measured using the Pediatric Quality of Life Inventory (PedsQL). The Immediate Postconcussion Assessment and Cognitive Test (ImPACT) was administered to assess neurocognitive and neurobehavioural sequelae. Results: Symptoms with the highest mean symptom scores on a Likert scale of 0-6 in 35 children at the time of assessment included headaches (3.1), poor concentration (2.7), memory problems (2.1), fatigue (2.1) and sensitivity to noise (2.0). Compared with normative data, children in this study had ImPACT summary scores between the 28th and 38th percentiles and a comparably low Cognitive Efficiency Index score. Mean scores for females were consistently statistically significantly lower (p \< 0.05) than for males across all of the HRQL domains. Trouble falling asleep and memory problems explained 62% of the variance in the PedsQL total scores. Conclusions: Children continue to experience many symptoms at least 3 months following sport-related head injuries that significantly impact their HRQL and neurocognitive abilities. © 2015 S. Karger AG, Basel.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Patton, D A; McIntosh, A S; Kleiven, S
In: Journal of Applied Biomechanics, vol. 31, no. 4, pp. 264–268, 2015.
@article{Patton2015,
title = {The biomechanical determinants of concussion: Finite element simulations to investigate tissue-level predictors of injury during sporting impacts to the unprotected head},
author = {Patton, D A and McIntosh, A S and Kleiven, S},
doi = {10.1123/jab.2014-0223},
year = {2015},
date = {2015-01-01},
journal = {Journal of Applied Biomechanics},
volume = {31},
number = {4},
pages = {264--268},
abstract = {Biomechanical studies of concussions have progressed from qualitative observations of head impacts to physical and numerical reconstructions, direct impact measurements, and finite element analyses. Supplementary to a previous study, which investigated maximum principal strain, the current study used a detailed finite element head model to simulate unhelmeted concussion and no-injury head impacts and evaluate the effectiveness of various tissue-level brain injury predictors: strain rate, product of strain and strain rate, cumulative strain damage measure, von Mises stress, and intracranial pressure. Von Mises stress was found to be the most effective predictor of concussion. It was also found that the thalamus and corpus callosum were brain regions with strong associations with concussion. Tentative tolerance limits for tissue-level predictors were proposed in an attempt to broaden the understanding of unhelmeted concussions. For the thalamus, tolerance limits were proposed for a 50% likelihood of concussion: 2.24 kPa, 24.0 s-1, and 2.49 s-1 for von Mises stress, strain rate, and the product of strain and strain rate, respectively. For the corpus callosum, tolerance limits were proposed for a 50% likelihood of concussion: 3.51 kPa, 25.1 s-1, and 2.76 s-1 for von Mises stress, strain rate, and the product of strain and strain rate, respectively. © 2015 Human Kinetics, Inc.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Gardner, A J; Iverson, G L; Quinn, T N; Makdissi, M; Levi, C R; Shultz, S R; Wright, D K; Stanwell, P
A preliminary video analysis of concussion in the National Rugby League Journal Article
In: Brain Injury, vol. 29, no. 10, pp. 1182–1185, 2015.
@article{Gardner2015b,
title = {A preliminary video analysis of concussion in the National Rugby League},
author = {Gardner, A J and Iverson, G L and Quinn, T N and Makdissi, M and Levi, C R and Shultz, S R and Wright, D K and Stanwell, P},
doi = {10.3109/02699052.2015.1034179},
year = {2015},
date = {2015-01-01},
journal = {Brain Injury},
volume = {29},
number = {10},
pages = {1182--1185},
abstract = {Primary objective: To conduct the first video analysis of concussion in the Australian National Rugby League (NRL) and describe player and injury characteristics, situational factors and time to return to play.Research design: Descriptive, observational case series.Methods and procedures: Video analysis of 20 medically diagnosed concussions for three consenting clubs during the 2013 NRL season.Main outcome and results: Most concussions (83%) occurred during a high tackle, and all injured ball carriers were hit high. Loss of consciousness was observed in 30% of cases. Common observable signs of injury included clutching of the head, balance problems or wobbly legs and a blank or vacant state. There were no post-concussive seizures. All players with loss of consciousness were removed from play. However, only half of the total sample was removed from play and one athlete who was removed returned to play in the same match. Of the players who were removed from play, the large majority returned the following week. Illegal play accounted for 25% of all concussions.Conclusions: Video analysis may be a useful method to study the incidence, mechanism and management of concussion in sports such as Rugby League. Future studies may include larger numbers to validate this preliminary data and may also investigate other levels of play and age ranges. © 2015 Taylor and Francis Group, LLC.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Dretsch, M N; Kelly, M P; Coldren, R L; Parish, R V; Russell, M L
In: Journal of Neurotrauma, vol. 32, no. 16, pp. 1217–1222, 2015.
@article{Dretsch2015a,
title = {No Significant Acute and Subacute Differences between Blast and Blunt Concussions across Multiple Neurocognitive Measures and Symptoms in Deployed Soldiers},
author = {Dretsch, M N and Kelly, M P and Coldren, R L and Parish, R V and Russell, M L},
doi = {10.1089/neu.2014.3637},
year = {2015},
date = {2015-01-01},
journal = {Journal of Neurotrauma},
volume = {32},
number = {16},
pages = {1217--1222},
abstract = {Seventy-one deployed U.S. Army soldiers who presented for concussion care due to either blast or blunt mechanisms within 72 h of injury were assessed using the Military Acute Concussion Evaluation, the Automated Neuropsychological Assessment Metrics (ANAM), traditional neuropsychological tests, and health status questionnaires. Follow-up ANAM testing was performed 10 d after initial testing (±5 d). Twenty-one soldiers were excluded: two for poor effort and 19 who had combined blast/blunt injuries. Of the remaining 50 male participants, 34 had blast injuries and 16 had blunt injuries. There were no statistically significant differences between blast injury and blunt injury participants in demographic, physical, or psychological health factors, concussive symptoms, or automated and traditional neurocognitive testing scores within 72 h post-injury. In addition, follow-up ANAM scores up to 15 d post-injury were not significantly different (available on 21 blast-injured and 13 blunt-injured subjects). Pre-injury baseline ANAM scores were compared where available, and revealed no statistically significant differences between 22 blast injury and eight blunt injury participants. These findings suggest there are no significant differences between mechanisms of injury during both the acute and subacute periods in neurobehavioral concussion sequelae while deployed in a combat environment. The current study supports the use of sports/mechanical concussion models for early concussion management in the deployed setting and exploration of variability in potential long-term outcomes. © Copyright 2015, Mary Ann Liebert, Inc.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Sikoglu, E M; Liso Navarro, A A; Czerniak, S M; McCafferty, J; Eisenstock, J; Stevenson, J H; King, J A; Moore, C M
Effects of Recent Concussion on Brain Bioenergetics: A Phosphorus-31 Magnetic Resonance Spectroscopy Study Journal Article
In: Cognitive and Behavioral Neurology, vol. 28, no. 4, pp. 181–187, 2015.
@article{Sikoglu2015,
title = {Effects of Recent Concussion on Brain Bioenergetics: A Phosphorus-31 Magnetic Resonance Spectroscopy Study},
author = {Sikoglu, E M and {Liso Navarro}, A A and Czerniak, S M and McCafferty, J and Eisenstock, J and Stevenson, J H and King, J A and Moore, C M},
doi = {10.1097/WNN.0000000000000076},
year = {2015},
date = {2015-01-01},
journal = {Cognitive and Behavioral Neurology},
volume = {28},
number = {4},
pages = {181--187},
abstract = {Background: Although clinical evaluations and neurocognitive assessments are commonly used to evaluate the extent of and recovery from concussion, brain bioenergetics could provide a more quantitative marker. The neurometabolic response to a concussion is thought to increase neuronal energy consumption and thus the demand for nucleoside triphosphate (NTP). Objective: We investigated the possible disruption in high-energy metabolism within the prefrontal cortex of college athletes who had either had a concussion within the past 6 months (n=14) or had never had a concussion (n=13). We hypothesized that concussed athletes would have imbalanced brain bioenergetics resulting from increased NTP consumption, and these biochemical changes would correspond to impaired cognitive abilities. Methods: We used phosphorus-31 magnetic resonance spectroscopy to quantify high-energy phosphates. We performed the neuroimaging in conjunction with neurocognitive assessments targeting prefrontal cortex-mediated tasks. Results: Our results revealed significantly lower $gamma$-NTP levels in the athletes after concussion. Although the concussed and non-concussed participants performed similarly in neurocognitive assessments, lower levels of $gamma$-NTP were associated with worse scores on neurocognitive tasks. Conclusions: Our results support the concept of increased energy demand in the prefrontal cortex of a concussed brain, and we found that while neurocognitive assessments appear normal, brain energetics may be abnormal. A longitudinal study could help establish brain NTP levels as a biomarker to aid in diagnosis and to assess recovery in concussed patients. © 2015 Wolters Kluwer Health, Inc.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Mayer, A R; Ling, J M; Dodd, A B; Gasparovic, C; Klimaj, S D; Meier, T B
A Longitudinal Assessment of Structural and Chemical Alterations in Mixed Martial Arts Fighters Journal Article
In: Journal of Neurotrauma, vol. 32, no. 22, pp. 1759–1767, 2015.
@article{Mayer2015b,
title = {A Longitudinal Assessment of Structural and Chemical Alterations in Mixed Martial Arts Fighters},
author = {Mayer, A R and Ling, J M and Dodd, A B and Gasparovic, C and Klimaj, S D and Meier, T B},
doi = {10.1089/neu.2014.3833},
year = {2015},
date = {2015-01-01},
journal = {Journal of Neurotrauma},
volume = {32},
number = {22},
pages = {1759--1767},
abstract = {Growing evidence suggests that temporally proximal acute concussions and repetitive subconcussive head injuries may lead to long-term neurological deficits. However, the underlying mechanisms of injury and their relative time-scales are not well documented in human injury models. The current study therefore investigated whether biomarkers of brain chemistry (magnetic resonance [MR] spectroscopy: N-acetylaspartate [NAA], combined glutamate and glutamine [Glx], total creatine [Cre], choline compounds [Cho], and myo-inositol [mI]) and structure (cortical thickness, white matter [WM]/subcortical volume) differed between mixed martial artists (MMA; n = 13) and matched healthy controls (HC) without a history of contact sport participation (HC; n = 14). A subset of participants (MMA = 9; HC = 10) returned for follow-up visits, with MMA (n = 3) with clinician-documented acute concussions also scanned serially. As expected, MMA self-reported a higher incidence of previous concussions and significantly more cognitive symptoms during prior concussion recovery. Fighters also exhibited reduced memory and processing speed relative to controls on neuropsychological testing coupled with cortical thinning in the left posterior cingulate gyrus and right occipital cortex at baseline assessment. Over a 1-year follow-up period, MMA experienced a significant decrease in both WM volume and NAA concentration, as well as relative thinning in the left middle and superior frontal gyri. These longitudinal changes did not correlate with self-reported metrics of injury (i.e., fight diary). In contrast, HC did not exhibit significant longitudinal changes over a 4-month follow-up period (p \> 0.05). Collectively, current results provide preliminary evidence of progressive changes in brain chemistry and structure over a relatively short time period in individuals with high exposure to repetitive head hits. These findings require replication in independent samples. © Mary Ann Liebert, Inc. 2015.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Terwilliger, V K; Pratson, L; Vaughan, C G; Gioia, G A
Additional Post-Concussion Impact Exposure May Affect Recovery in Adolescent Athletes Journal Article
In: Journal of Neurotrauma, vol. 33, no. 8, pp. 761–765, 2016.
Abstract | Links | BibTeX | Tags: Adolescent, Article, athlete, Athletes, brain concussion, Brain Injury, clinical article, Concussion, controlled study, CONVALESCENCE, Female, human, Male, mTBI, Parent, postconcussion syndrome, retrospective study, risk factor, sport injury
@article{Terwilliger2016,
title = {Additional Post-Concussion Impact Exposure May Affect Recovery in Adolescent Athletes},
author = {Terwilliger, V K and Pratson, L and Vaughan, C G and Gioia, G A},
doi = {10.1089/neu.2015.4082},
year = {2016},
date = {2016-01-01},
journal = {Journal of Neurotrauma},
volume = {33},
number = {8},
pages = {761--765},
abstract = {Repeat concussion has been associated with risk for prolonged and pronounced clinical recovery in athletes. In this study of adolescent athletes, we examined whether an additional head impact within 24 h of a sports-related concussion (SRC) is associated with higher symptom burden and prolonged clinical recovery compared with a single-injury group. Forty-two student-athletes (52% male, mean age = 14.9 years) diagnosed with an SRC in a concussion clinic were selected for this study: (1) 21 athletes who sustained an additional significant head impact within 24 h of the initial injury (additional-impact group); (2) 21 single-injury athletes, age and gender matched, who sustained only one discrete concussive blow to the head (single-injury group). Groups did not differ on initial injury characteristics or pre-injury risk factors. The effect of injury status (single-vs. additional-impact) was examined on athlete-and parent-reported symptom burden (at first clinic visit) and length of recovery (LOR). Higher symptom burden was reported by the athletes and parents in the additional-impact group at the time of first visit. The additional-impact group also had a significantly longer LOR compared with the single-injury group. These findings provide preliminary, hypothesis-generating evidence for the importance of immediate removal from play following an SRC to protect athletes from re-injury, which may worsen symptoms and prolong recovery. The retrospective study design from a specialized clinical sample points to the need for future prospective studies of the relationship between single-and additional-impact injuries on symptom burden and LOR. © 2016 Mary Ann Liebert, Inc.},
keywords = {Adolescent, Article, athlete, Athletes, brain concussion, Brain Injury, clinical article, Concussion, controlled study, CONVALESCENCE, Female, human, Male, mTBI, Parent, postconcussion syndrome, retrospective study, risk factor, sport injury},
pubstate = {published},
tppubtype = {article}
}
Abaji, J P; Curnier, D; Moore, R D; Ellemberg, D
Persisting effects of concussion on heart rate variability during physical exertion Journal Article
In: Journal of Neurotrauma, vol. 33, no. 9, pp. 811–817, 2016.
Abstract | Links | BibTeX | Tags: adult, Article, athlete, brain concussion, cardiac autonomic modulation, clinical article, Concussion, controlled study, cross-sectional study, electrocardiogram, exercise, hand grip, heart rate variability, human, isometric hand grip contraction, Male, muscle isometric contraction, PHYSICAL ACTIVITY
@article{Abaji2016,
title = {Persisting effects of concussion on heart rate variability during physical exertion},
author = {Abaji, J P and Curnier, D and Moore, R D and Ellemberg, D},
doi = {10.1089/neu.2015.3989},
year = {2016},
date = {2016-01-01},
journal = {Journal of Neurotrauma},
volume = {33},
number = {9},
pages = {811--817},
abstract = {The purpose of this study was to evaluate cardiac autonomic modulation in university athletes during the post-acute to late phase (mean, 95 days ±63) of injury at rest and during physical exertion. We also sought to evaluate the effect of time since injury and number of injuries on heart rate variability (HRV). We hypothesized that physical exertion would reveal persisting modifications in HRV following a concussion. We included, in a cross-sectional design, athletes who sustained a concussion and matched controls. Concussions were identified by a medical doctor using established criteria. Twelve male concussed and 12 control athletes took part in the study. Control participants were teammates who were chosen to match the concussed athletes with regard to their height, weight, education, and age. The beat-to-beat electrocardiogram intervals of the participants were measured at rest and during physical exertion (isometric hand grip contraction; IHGC), which was sustained for 3 minutes at 30% of the participants' maximum. Linear and nonlinear parameters of HRV were calculated. The ratio between low and high frequency (LF/HF) bands was calculated to assess the sympathovagal balance. During the IHGC, but not at rest, concussed athletes presented significantly lower power in HF bands, leading to a significantly higher LF/HF ratio (p ≤ 0.05). Thus, asymptomatic athletes still may exhibit modifications in cardiac autonomic modulation weeks to months following injury. These modifications may only become apparent during physical exertion. Monitoring HRV may aid diagnosis and provide insight about safe return to play. © Mary Ann Liebert, Inc. 2016.},
keywords = {adult, Article, athlete, brain concussion, cardiac autonomic modulation, clinical article, Concussion, controlled study, cross-sectional study, electrocardiogram, exercise, hand grip, heart rate variability, human, isometric hand grip contraction, Male, muscle isometric contraction, PHYSICAL ACTIVITY},
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}
}
Vassilyadi, M; Macartney, G; Barrowman, N; Anderson, P; Dube, K
Symptom experience and quality of life in children after sport-related head injuries: A cross-sectional study Journal Article
In: Pediatric Neurosurgery, vol. 50, no. 4, pp. 196–203, 2015.
Abstract | Links | BibTeX | Tags: Adolescent, adult, affect, Article, Athletic Injuries, behavior disorder, brain concussion, Child, clinical article, clinical assessment, cognitive defect, Cognitive Efficiency Index, complication, Concussion, Concussion Symptom Scale, controlled study, Craniocerebral Trauma, Cross-Sectional Studies, cross-sectional study, fatigue, Female, head injury, headache, human, Humans, Immediate Postconcussion Assessment and Cognitive, Likert scale, Male, memory disorder, mild traumatic brain injury, neuropsychological test, noise, Paediatric patients, Pediatric Quality of Life Inventory, postconcussion syndrome, priority journal, psychology, quality of life, rating scale, scoring system, Sport, sport injury, Sports, symptom, time factor, Time Factors, traumatic brain injury, trends
@article{Vassilyadi2015,
title = {Symptom experience and quality of life in children after sport-related head injuries: A cross-sectional study},
author = {Vassilyadi, M and Macartney, G and Barrowman, N and Anderson, P and Dube, K},
doi = {10.1159/000431232},
year = {2015},
date = {2015-01-01},
journal = {Pediatric Neurosurgery},
volume = {50},
number = {4},
pages = {196--203},
abstract = {Background: Sports are a major cause of concussions, and little is known about the symptom experience and health-related quality of life (HRQL) in children who remain symptomatic for over 3 months following such head injuries. Methods: A cross-sectional study of children aged 10-18 years was performed who were referred to the Neurosurgery Clinic at our centre following a head injury. Symptom experience was measured using the modified Concussion Symptom Scale, and HRQL was measured using the Pediatric Quality of Life Inventory (PedsQL). The Immediate Postconcussion Assessment and Cognitive Test (ImPACT) was administered to assess neurocognitive and neurobehavioural sequelae. Results: Symptoms with the highest mean symptom scores on a Likert scale of 0-6 in 35 children at the time of assessment included headaches (3.1), poor concentration (2.7), memory problems (2.1), fatigue (2.1) and sensitivity to noise (2.0). Compared with normative data, children in this study had ImPACT summary scores between the 28th and 38th percentiles and a comparably low Cognitive Efficiency Index score. Mean scores for females were consistently statistically significantly lower (p \< 0.05) than for males across all of the HRQL domains. Trouble falling asleep and memory problems explained 62% of the variance in the PedsQL total scores. Conclusions: Children continue to experience many symptoms at least 3 months following sport-related head injuries that significantly impact their HRQL and neurocognitive abilities. © 2015 S. Karger AG, Basel.},
keywords = {Adolescent, adult, affect, Article, Athletic Injuries, behavior disorder, brain concussion, Child, clinical article, clinical assessment, cognitive defect, Cognitive Efficiency Index, complication, Concussion, Concussion Symptom Scale, controlled study, Craniocerebral Trauma, Cross-Sectional Studies, cross-sectional study, fatigue, Female, head injury, headache, human, Humans, Immediate Postconcussion Assessment and Cognitive, Likert scale, Male, memory disorder, mild traumatic brain injury, neuropsychological test, noise, Paediatric patients, Pediatric Quality of Life Inventory, postconcussion syndrome, priority journal, psychology, quality of life, rating scale, scoring system, Sport, sport injury, Sports, symptom, time factor, Time Factors, traumatic brain injury, trends},
pubstate = {published},
tppubtype = {article}
}
Patton, D A; McIntosh, A S; Kleiven, S
In: Journal of Applied Biomechanics, vol. 31, no. 4, pp. 264–268, 2015.
Abstract | Links | BibTeX | Tags: Article, Biomechanics, brain, Brain Injury, brain region, clinical article, Concussion, corpus callosum, Damage detection, evaluation study, finite element analysis, Finite element head models, Finite element method, Finite element simulations, football, gray matter, Head Injuries, head injury, human, Intra-cranial pressure, intracranial pressure, investigative procedures, Maximum principal strain, mesencephalon, Modeling, Models, Numerical reconstruction, Qualitative observations, Sport, sport injury, Sports, Strain and strain rates, Strain rate, Stress, thalamus, Tissue, tissue level
@article{Patton2015,
title = {The biomechanical determinants of concussion: Finite element simulations to investigate tissue-level predictors of injury during sporting impacts to the unprotected head},
author = {Patton, D A and McIntosh, A S and Kleiven, S},
doi = {10.1123/jab.2014-0223},
year = {2015},
date = {2015-01-01},
journal = {Journal of Applied Biomechanics},
volume = {31},
number = {4},
pages = {264--268},
abstract = {Biomechanical studies of concussions have progressed from qualitative observations of head impacts to physical and numerical reconstructions, direct impact measurements, and finite element analyses. Supplementary to a previous study, which investigated maximum principal strain, the current study used a detailed finite element head model to simulate unhelmeted concussion and no-injury head impacts and evaluate the effectiveness of various tissue-level brain injury predictors: strain rate, product of strain and strain rate, cumulative strain damage measure, von Mises stress, and intracranial pressure. Von Mises stress was found to be the most effective predictor of concussion. It was also found that the thalamus and corpus callosum were brain regions with strong associations with concussion. Tentative tolerance limits for tissue-level predictors were proposed in an attempt to broaden the understanding of unhelmeted concussions. For the thalamus, tolerance limits were proposed for a 50% likelihood of concussion: 2.24 kPa, 24.0 s-1, and 2.49 s-1 for von Mises stress, strain rate, and the product of strain and strain rate, respectively. For the corpus callosum, tolerance limits were proposed for a 50% likelihood of concussion: 3.51 kPa, 25.1 s-1, and 2.76 s-1 for von Mises stress, strain rate, and the product of strain and strain rate, respectively. © 2015 Human Kinetics, Inc.},
keywords = {Article, Biomechanics, brain, Brain Injury, brain region, clinical article, Concussion, corpus callosum, Damage detection, evaluation study, finite element analysis, Finite element head models, Finite element method, Finite element simulations, football, gray matter, Head Injuries, head injury, human, Intra-cranial pressure, intracranial pressure, investigative procedures, Maximum principal strain, mesencephalon, Modeling, Models, Numerical reconstruction, Qualitative observations, Sport, sport injury, Sports, Strain and strain rates, Strain rate, Stress, thalamus, Tissue, tissue level},
pubstate = {published},
tppubtype = {article}
}
Gardner, A J; Iverson, G L; Quinn, T N; Makdissi, M; Levi, C R; Shultz, S R; Wright, D K; Stanwell, P
A preliminary video analysis of concussion in the National Rugby League Journal Article
In: Brain Injury, vol. 29, no. 10, pp. 1182–1185, 2015.
Abstract | Links | BibTeX | Tags: Article, athlete, Athletes, brain concussion, case study, clinical article, Concussion, descriptive research, EPIDEMIOLOGY, human, Incidence, Injury surveillance, observational study, rugby, sport injury, unconsciousness, videorecording
@article{Gardner2015b,
title = {A preliminary video analysis of concussion in the National Rugby League},
author = {Gardner, A J and Iverson, G L and Quinn, T N and Makdissi, M and Levi, C R and Shultz, S R and Wright, D K and Stanwell, P},
doi = {10.3109/02699052.2015.1034179},
year = {2015},
date = {2015-01-01},
journal = {Brain Injury},
volume = {29},
number = {10},
pages = {1182--1185},
abstract = {Primary objective: To conduct the first video analysis of concussion in the Australian National Rugby League (NRL) and describe player and injury characteristics, situational factors and time to return to play.Research design: Descriptive, observational case series.Methods and procedures: Video analysis of 20 medically diagnosed concussions for three consenting clubs during the 2013 NRL season.Main outcome and results: Most concussions (83%) occurred during a high tackle, and all injured ball carriers were hit high. Loss of consciousness was observed in 30% of cases. Common observable signs of injury included clutching of the head, balance problems or wobbly legs and a blank or vacant state. There were no post-concussive seizures. All players with loss of consciousness were removed from play. However, only half of the total sample was removed from play and one athlete who was removed returned to play in the same match. Of the players who were removed from play, the large majority returned the following week. Illegal play accounted for 25% of all concussions.Conclusions: Video analysis may be a useful method to study the incidence, mechanism and management of concussion in sports such as Rugby League. Future studies may include larger numbers to validate this preliminary data and may also investigate other levels of play and age ranges. © 2015 Taylor and Francis Group, LLC.},
keywords = {Article, athlete, Athletes, brain concussion, case study, clinical article, Concussion, descriptive research, EPIDEMIOLOGY, human, Incidence, Injury surveillance, observational study, rugby, sport injury, unconsciousness, videorecording},
pubstate = {published},
tppubtype = {article}
}
Dretsch, M N; Kelly, M P; Coldren, R L; Parish, R V; Russell, M L
In: Journal of Neurotrauma, vol. 32, no. 16, pp. 1217–1222, 2015.
Abstract | Links | BibTeX | Tags: 2003-2011, acute disease, Adolescent, adult, amnesia, ANAM, Article, assessment of humans, Automated Neuropsychological Assessment Metrics, Blast injuries, blast injury, blunt trauma, brain concussion, clinical article, cognition, Cognition Disorders, cognitive screening, comparative study, complication, concussion mechanism, Demography, deployment, Female, follow up, health status, human, Humans, Iraq War, Male, middle aged, Military, Military Acute Concussion Evaluation, Military personnel, neuropsychological test, Neuropsychological Tests, soldier, unconsciousness, UNITED States, War, Young Adult
@article{Dretsch2015a,
title = {No Significant Acute and Subacute Differences between Blast and Blunt Concussions across Multiple Neurocognitive Measures and Symptoms in Deployed Soldiers},
author = {Dretsch, M N and Kelly, M P and Coldren, R L and Parish, R V and Russell, M L},
doi = {10.1089/neu.2014.3637},
year = {2015},
date = {2015-01-01},
journal = {Journal of Neurotrauma},
volume = {32},
number = {16},
pages = {1217--1222},
abstract = {Seventy-one deployed U.S. Army soldiers who presented for concussion care due to either blast or blunt mechanisms within 72 h of injury were assessed using the Military Acute Concussion Evaluation, the Automated Neuropsychological Assessment Metrics (ANAM), traditional neuropsychological tests, and health status questionnaires. Follow-up ANAM testing was performed 10 d after initial testing (±5 d). Twenty-one soldiers were excluded: two for poor effort and 19 who had combined blast/blunt injuries. Of the remaining 50 male participants, 34 had blast injuries and 16 had blunt injuries. There were no statistically significant differences between blast injury and blunt injury participants in demographic, physical, or psychological health factors, concussive symptoms, or automated and traditional neurocognitive testing scores within 72 h post-injury. In addition, follow-up ANAM scores up to 15 d post-injury were not significantly different (available on 21 blast-injured and 13 blunt-injured subjects). Pre-injury baseline ANAM scores were compared where available, and revealed no statistically significant differences between 22 blast injury and eight blunt injury participants. These findings suggest there are no significant differences between mechanisms of injury during both the acute and subacute periods in neurobehavioral concussion sequelae while deployed in a combat environment. The current study supports the use of sports/mechanical concussion models for early concussion management in the deployed setting and exploration of variability in potential long-term outcomes. © Copyright 2015, Mary Ann Liebert, Inc.},
keywords = {2003-2011, acute disease, Adolescent, adult, amnesia, ANAM, Article, assessment of humans, Automated Neuropsychological Assessment Metrics, Blast injuries, blast injury, blunt trauma, brain concussion, clinical article, cognition, Cognition Disorders, cognitive screening, comparative study, complication, concussion mechanism, Demography, deployment, Female, follow up, health status, human, Humans, Iraq War, Male, middle aged, Military, Military Acute Concussion Evaluation, Military personnel, neuropsychological test, Neuropsychological Tests, soldier, unconsciousness, UNITED States, War, Young Adult},
pubstate = {published},
tppubtype = {article}
}
Sikoglu, E M; Liso Navarro, A A; Czerniak, S M; McCafferty, J; Eisenstock, J; Stevenson, J H; King, J A; Moore, C M
Effects of Recent Concussion on Brain Bioenergetics: A Phosphorus-31 Magnetic Resonance Spectroscopy Study Journal Article
In: Cognitive and Behavioral Neurology, vol. 28, no. 4, pp. 181–187, 2015.
Abstract | Links | BibTeX | Tags: Adolescent, adult, Article, athlete, Athletic Injuries, biochemical analysis, bioenergy, brain concussion, clinical article, cognition, college, Concussion, energy consumption, Energy Metabolism, Female, high energy phosphate, human, Humans, Longitudinal studies, longitudinal study, Magnetic Resonance Spectroscopy, Male, metabolism, MR spectroscopy (phosphorus-31), neuroimaging, NTP, NUCLEAR magnetic resonance spectroscopy, nucleoside, nucleoside triphosphate, Nucleosides, Pathophysiology, phosphate, Phosphates, phosphorus, Phosphorus Isotopes, phosphorus nuclear magnetic resonance, PHYSIOLOGY, Prefrontal Cortex, priority journal, procedures, sport injury, Universities, university, Young Adult
@article{Sikoglu2015,
title = {Effects of Recent Concussion on Brain Bioenergetics: A Phosphorus-31 Magnetic Resonance Spectroscopy Study},
author = {Sikoglu, E M and {Liso Navarro}, A A and Czerniak, S M and McCafferty, J and Eisenstock, J and Stevenson, J H and King, J A and Moore, C M},
doi = {10.1097/WNN.0000000000000076},
year = {2015},
date = {2015-01-01},
journal = {Cognitive and Behavioral Neurology},
volume = {28},
number = {4},
pages = {181--187},
abstract = {Background: Although clinical evaluations and neurocognitive assessments are commonly used to evaluate the extent of and recovery from concussion, brain bioenergetics could provide a more quantitative marker. The neurometabolic response to a concussion is thought to increase neuronal energy consumption and thus the demand for nucleoside triphosphate (NTP). Objective: We investigated the possible disruption in high-energy metabolism within the prefrontal cortex of college athletes who had either had a concussion within the past 6 months (n=14) or had never had a concussion (n=13). We hypothesized that concussed athletes would have imbalanced brain bioenergetics resulting from increased NTP consumption, and these biochemical changes would correspond to impaired cognitive abilities. Methods: We used phosphorus-31 magnetic resonance spectroscopy to quantify high-energy phosphates. We performed the neuroimaging in conjunction with neurocognitive assessments targeting prefrontal cortex-mediated tasks. Results: Our results revealed significantly lower $gamma$-NTP levels in the athletes after concussion. Although the concussed and non-concussed participants performed similarly in neurocognitive assessments, lower levels of $gamma$-NTP were associated with worse scores on neurocognitive tasks. Conclusions: Our results support the concept of increased energy demand in the prefrontal cortex of a concussed brain, and we found that while neurocognitive assessments appear normal, brain energetics may be abnormal. A longitudinal study could help establish brain NTP levels as a biomarker to aid in diagnosis and to assess recovery in concussed patients. © 2015 Wolters Kluwer Health, Inc.},
keywords = {Adolescent, adult, Article, athlete, Athletic Injuries, biochemical analysis, bioenergy, brain concussion, clinical article, cognition, college, Concussion, energy consumption, Energy Metabolism, Female, high energy phosphate, human, Humans, Longitudinal studies, longitudinal study, Magnetic Resonance Spectroscopy, Male, metabolism, MR spectroscopy (phosphorus-31), neuroimaging, NTP, NUCLEAR magnetic resonance spectroscopy, nucleoside, nucleoside triphosphate, Nucleosides, Pathophysiology, phosphate, Phosphates, phosphorus, Phosphorus Isotopes, phosphorus nuclear magnetic resonance, PHYSIOLOGY, Prefrontal Cortex, priority journal, procedures, sport injury, Universities, university, Young Adult},
pubstate = {published},
tppubtype = {article}
}
Mayer, A R; Ling, J M; Dodd, A B; Gasparovic, C; Klimaj, S D; Meier, T B
A Longitudinal Assessment of Structural and Chemical Alterations in Mixed Martial Arts Fighters Journal Article
In: Journal of Neurotrauma, vol. 32, no. 22, pp. 1759–1767, 2015.
Abstract | Links | BibTeX | Tags: Adolescent, adult, Article, biological marker, Biomarkers, BRAIN chemistry, brain concussion, brain cortex, brain size, Cerebral Cortex, CHOLINE, clinical article, cognition, Concussion, controlled study, cortical thickness (brain), creatine, executive function, Female, follow up, Follow-Up Studies, frontal gyrus, glutamic acid, glutamine, human, Humans, Injuries, inositol, Longitudinal, Longitudinal studies, longitudinal study, Magnetic Resonance Imaging, Male, martial art, Martial Arts, Memory, middle aged, mixed martial art, n acetylaspartic acid, neuropsychological test, Neuropsychological Tests, nuclear magnetic resonance imaging, NUCLEAR magnetic resonance spectroscopy, occipital cortex, pathology, posterior cingulate, psychology, repetitive injury, Spectroscopy, volumetrics, white matter, Young Adult
@article{Mayer2015b,
title = {A Longitudinal Assessment of Structural and Chemical Alterations in Mixed Martial Arts Fighters},
author = {Mayer, A R and Ling, J M and Dodd, A B and Gasparovic, C and Klimaj, S D and Meier, T B},
doi = {10.1089/neu.2014.3833},
year = {2015},
date = {2015-01-01},
journal = {Journal of Neurotrauma},
volume = {32},
number = {22},
pages = {1759--1767},
abstract = {Growing evidence suggests that temporally proximal acute concussions and repetitive subconcussive head injuries may lead to long-term neurological deficits. However, the underlying mechanisms of injury and their relative time-scales are not well documented in human injury models. The current study therefore investigated whether biomarkers of brain chemistry (magnetic resonance [MR] spectroscopy: N-acetylaspartate [NAA], combined glutamate and glutamine [Glx], total creatine [Cre], choline compounds [Cho], and myo-inositol [mI]) and structure (cortical thickness, white matter [WM]/subcortical volume) differed between mixed martial artists (MMA; n = 13) and matched healthy controls (HC) without a history of contact sport participation (HC; n = 14). A subset of participants (MMA = 9; HC = 10) returned for follow-up visits, with MMA (n = 3) with clinician-documented acute concussions also scanned serially. As expected, MMA self-reported a higher incidence of previous concussions and significantly more cognitive symptoms during prior concussion recovery. Fighters also exhibited reduced memory and processing speed relative to controls on neuropsychological testing coupled with cortical thinning in the left posterior cingulate gyrus and right occipital cortex at baseline assessment. Over a 1-year follow-up period, MMA experienced a significant decrease in both WM volume and NAA concentration, as well as relative thinning in the left middle and superior frontal gyri. These longitudinal changes did not correlate with self-reported metrics of injury (i.e., fight diary). In contrast, HC did not exhibit significant longitudinal changes over a 4-month follow-up period (p \> 0.05). Collectively, current results provide preliminary evidence of progressive changes in brain chemistry and structure over a relatively short time period in individuals with high exposure to repetitive head hits. These findings require replication in independent samples. © Mary Ann Liebert, Inc. 2015.},
keywords = {Adolescent, adult, Article, biological marker, Biomarkers, BRAIN chemistry, brain concussion, brain cortex, brain size, Cerebral Cortex, CHOLINE, clinical article, cognition, Concussion, controlled study, cortical thickness (brain), creatine, executive function, Female, follow up, Follow-Up Studies, frontal gyrus, glutamic acid, glutamine, human, Humans, Injuries, inositol, Longitudinal, Longitudinal studies, longitudinal study, Magnetic Resonance Imaging, Male, martial art, Martial Arts, Memory, middle aged, mixed martial art, n acetylaspartic acid, neuropsychological test, Neuropsychological Tests, nuclear magnetic resonance imaging, NUCLEAR magnetic resonance spectroscopy, occipital cortex, pathology, posterior cingulate, psychology, repetitive injury, Spectroscopy, volumetrics, white matter, Young Adult},
pubstate = {published},
tppubtype = {article}
}