Hwang, Sungjae; Ma, Lei; Kawata, Keisuke; Tierney, Ryan; Jeka, John J
Vestibular dysfunction after subconcussive head impact Journal Article
In: Journal of Neurotrauma, vol. 34, no. 1, pp. 8–15, 2017, ISBN: 0897-7151 1557-9042.
Abstract | Links | BibTeX | Tags: 2017, BEHAVIORAL assessment, Behavioral assessments, Head trauma, Human studies, Outcome measures, Sensory Feedback, sensory function, Soccer, traumatic brain injury
@article{Hwang2017,
title = {Vestibular dysfunction after subconcussive head impact},
author = {Hwang, Sungjae and Ma, Lei and Kawata, Keisuke and Tierney, Ryan and Jeka, John J},
doi = {10.1089/neu.2015.4238},
isbn = {0897-7151
1557-9042},
year = {2017},
date = {2017-01-01},
journal = {Journal of Neurotrauma},
volume = {34},
number = {1},
pages = {8--15},
publisher = {Mary Ann Liebert, Inc.},
address = {US},
abstract = {Current thinking views mild head impact (i.e., subconcussion) as an underrecognized phenomenon that has the ability to cause significant current and future detrimental neurological effects. Repeated mild impacts to the head, however, often display no observable behavioral deficits based on standard clinical tests, which may lack sensitivity. The current study investigates the effects of subconcussive impacts from soccer heading with innovative measures of vestibular function and walking stability in a pre- 0\textendash2 h, post- 24 h post-heading repeated measures design. The heading group (n = 10) executed 10 headers with soccer balls projected at a velocity of 25 mph (11.2 m/sec) over 10 min. Subjects were evaluated 24 h before, immediately after, and 24 h after soccer heading with: the modified Balance Error Scoring System (mBESS); a walking stability task with visual feedback of trunk movement; and galvanic vestibular stimulation (GVS) while standing with eyes closed on foam. A control group (n = 10) followed the same protocol with no heading. The results showed significant decrease in trunk angle, leg angle gain, and center of mass gain relative to GVS for the heading group compared with controls. Medial-lateral trunk orientation displacement and velocity during treadmill walking increased immediately after mild head impact for the heading group compared with controls. Controls showed an improvement in mBESS scores over time, indicating a learning effect, which was not observed with the heading group. These results suggest that mild head impact leads to a transient dysfunction in vestibular processing, which deters walking stability during task performance. (PsycINFO Database Record (c) 2017 APA, all rights reserved)},
keywords = {2017, BEHAVIORAL assessment, Behavioral assessments, Head trauma, Human studies, Outcome measures, Sensory Feedback, sensory function, Soccer, traumatic brain injury},
pubstate = {published},
tppubtype = {article}
}
Wojtowicz, M; Iverson, G L; Silverberg, N D; Mannix, R; Zafonte, R; Maxwell, B; Berkner, P D
Consistency of Self-Reported Concussion History in Adolescent Athletes Journal Article
In: Journal of Neurotrauma, vol. 34, no. 2, pp. 322–327, 2017.
Abstract | Links | BibTeX | Tags: assessment tools, Head trauma, pediatric brain injury
@article{Wojtowicz2017,
title = {Consistency of Self-Reported Concussion History in Adolescent Athletes},
author = {Wojtowicz, M and Iverson, G L and Silverberg, N D and Mannix, R and Zafonte, R and Maxwell, B and Berkner, P D},
doi = {10.1089/neu.2016.4412},
year = {2017},
date = {2017-01-01},
journal = {Journal of Neurotrauma},
volume = {34},
number = {2},
pages = {322--327},
abstract = {Relying on self-reported concussion injury history is common in both clinical care and research. However, young athletes may not provide consistent medical information. To date, little is known about the reliability of self-reported concussion history in high school students. This study examined whether student athletes reported their lifetime history of concussions consistently over time. Self-reported concussion history was examined in 4792 student athletes (ages 13-18) from Maine who completed a preseason health survey on two occasions (median re-test interval = 23.7 months; standard deviation = 7.3; interquartile range = 12.4-24.5). Consistency of self-reported concussion history was determined by differences in the number of concussions reported during the second survey. Inconsistent concussion history was defined primarily by a decrease in the number of lifetime concussions reported at the second testing, compared with at the first testing. The majority of the sample (80.3%) reported no change in the number of concussions between the two baseline assessments. A minority (15.9%; n = 763) reported more concussions during the second assessment. Only 3.8% (n = 181) of student athletes provided inconsistent concussion histories, defined as fewer concussions at the second assessment. Boys provided inconsistent concussion histories a little more frequently, compared with girls (5.3% and 2.0%, respectively; p \< 0.001). Similarly, athletes with self-reported attention-deficit hyperactivity disorder (ADHD) provided inconsistent concussion histories somewhat more frequently, compared with those without ADHD (7.8% and 3.5%, respectively; p \< 0.001). Of the athletes with inconsistent concussion histories, greater degree of inconsistency was associated with a greater number of concussions initially reported at baseline (rs = 0.54; p \< 0.001). Only a small proportion of student athletes provided inconsistent concussion histories. Male gender, ADHD, and greater number of baseline concussions were significantly associated with inconsistency in reporting. Overall, these findings suggest that student athletes are quite consistent when reporting their concussion history when surveyed twice during high school. Copyright © 2017, Mary Ann Liebert, Inc. 2017.},
keywords = {assessment tools, Head trauma, pediatric brain injury},
pubstate = {published},
tppubtype = {article}
}
Oliver, J M; Jones, M T; Kirk, K M; Gable, D A; Repshas, J T; Johnson, T A; Andréasson, U; Norgren, N; Blennow, K; Zetterberg, H
Serum Neurofilament Light in American Football Athletes over the Course of a Season Journal Article
In: Journal of Neurotrauma, vol. 33, no. 19, pp. 1784–1789, 2016.
Abstract | Links | BibTeX | Tags: adult brain injury, axonal injury, Biomarkers, Head trauma, traumatic brain injury
@article{Oliver2016,
title = {Serum Neurofilament Light in American Football Athletes over the Course of a Season},
author = {Oliver, J M and Jones, M T and Kirk, K M and Gable, D A and Repshas, J T and Johnson, T A and Andr\'{e}asson, U and Norgren, N and Blennow, K and Zetterberg, H},
doi = {10.1089/neu.2015.4295},
year = {2016},
date = {2016-01-01},
journal = {Journal of Neurotrauma},
volume = {33},
number = {19},
pages = {1784--1789},
abstract = {Despite being underreported, American football boasts the highest incidence of concussion among all team sports, likely due to exposure to head impacts that vary in number and magnitude over the season. This study compared a biological marker of head trauma in American football athletes with non-contact sport athletes and examined changes over the course of a season. Baseline serum neurofilament light polypeptide (NFL) was measured after 9 weeks of no contact and compared with a non-contact sport. Serum NFL was then measured over the course of the entire season at eight time-points coincident with expected changes in likelihood of increased head impacts. Data were compared between starters (n = 11) and non-starters (n = 9). Compared with non-starters (mean ± standard deviation) (7.30 ± 3.57 pg•mL-1) and controls (6.75 ± 1.68 pg•mL-1), serum NFL in starters (8.45 ± 5.90 pg•mL-1) was higher at baseline (mean difference; ±90% confidence interval) (1.69; ± 1.96 pg•mL-1 and 1.15; ± 1.4 pg•mL-1, respectively). Over the course of the season, an increase (effect size [ES] = 1.8; p \< 0.001) was observed post-camp relative to baseline (1.52 ± 1.18 pg•mL-1), which remained elevated until conference play, when a second increase was observed (ES = 2.6; p = 0.008) over baseline (4.82 ± 2.64 pg•mL-1). A lack of change in non-starters resulted in substantial differences between starters and non-starters over the course of the season. These data suggest that a season of collegiate American football is associated with elevations in serum NFL, which is indicative of axonal injury, as a result of head impacts. Copyright © 2016, Mary Ann Liebert, Inc.},
keywords = {adult brain injury, axonal injury, Biomarkers, Head trauma, traumatic brain injury},
pubstate = {published},
tppubtype = {article}
}
Oliver, J M; Jones, M T; Kirk, K M; Gable, D A; Repshas, J T; Johnson, T A; Andréasson, U; Norgren, N; Blennow, K; Zetterberg, H
Effect of docosahexaenoic acid on a biomarker of head trauma in American Football Journal Article
In: Medicine & Science in Sports & Exercise, vol. 48, no. 6, pp. 974–982, 2016.
Abstract | Links | BibTeX | Tags: Concussion, DHA, Head trauma, NEUROFILAMENT LIGHT
@article{Oliver2016a,
title = {Effect of docosahexaenoic acid on a biomarker of head trauma in American Football},
author = {Oliver, J M and Jones, M T and Kirk, K M and Gable, D A and Repshas, J T and Johnson, T A and Andr\'{e}asson, U and Norgren, N and Blennow, K and Zetterberg, H},
doi = {10.1249/MSS.0000000000000875},
year = {2016},
date = {2016-01-01},
journal = {Medicine \& Science in Sports \& Exercise},
volume = {48},
number = {6},
pages = {974--982},
abstract = {Purpose American football athletes are exposed to subconcussive impacts over the course of the season resulting in elevations in serum neurofilament light (NFL), a biomarker of axonal injury. Docosahexaenoic acid (DHA) has been reported to reduce axonal trauma associated with traumatic brain injury in rodent models. However, the optimal dose in American football athletes is unknown. This study examined the effect of differing doses of DHA on serum NFL over the course of a season of American football. Methods In a randomized, double-blind, placebo-controlled, parallel design, 81 National Collegiate Athletic Association Division I American football athletes were assigned to ingest either 2, 4, 6 g·d -1 of DHA or placebo. Blood was sampled at specific times over the course of 189 d, coincident with changes in intensity, hours of contact, and likely changes in head impacts. Standardized magnitude-based inference was used to define outcomes. Results DHA supplementation increased plasma DHA in a dose-dependent manner (2 g·d -1: mean difference from baseline; ±90% CL; 2 g·d -1: 1.3; ±0.6; 4 g·d -1: 1.6; ±0.7%; 6 g·d -1: 2.8; ±1.2%). Serum NFL increased to a greater extent in starters (area under the curve, 1995 ± 1383 pg·mL -1) versus nonstarters (1398 ± 581 pg·mL -1; P = 0.024). Irrespective of dose, supplemental DHA likely attenuated serum NFL coincident with increases in serum NFL by likely small and moderate magnitude (effect size = 0.4-0.7). Conclusions Findings from this study, the first large-scale study examining potential prophylactic use of DHA in American football athletes, include identification of optimal dose of DHA, suggesting a neuroprotective effect of DHA supplementation. © 2016 by the American College of Sports Medicine.},
keywords = {Concussion, DHA, Head trauma, NEUROFILAMENT LIGHT},
pubstate = {published},
tppubtype = {article}
}
Brewster, R; Bi, W L; Smith, T R; Gormley, W B; Dunn, I F; Laws Jr., E R
The neurosurgeon as baseball fan and inventor: Walter Dandy and the batter's helmet Journal Article
In: Neurosurgical Focus, vol. 39, no. 1, 2015.
Abstract | Links | BibTeX | Tags: 19th Century, 20th Century, Baseball, Baseball helmet, brain concussion, Head Protective Devices, Head trauma, Helmet, HISTORY, human, Humans, Injuries, Innovation, Male, middle aged, neurosurgeon, Neurosurgeons, Protective gear, traumatic brain injury, Walter dandy
@article{Brewster2015,
title = {The neurosurgeon as baseball fan and inventor: Walter Dandy and the batter's helmet},
author = {Brewster, R and Bi, W L and Smith, T R and Gormley, W B and Dunn, I F and {Laws Jr.}, E R},
doi = {10.3171/2015.3.FOCUS1552},
year = {2015},
date = {2015-01-01},
journal = {Neurosurgical Focus},
volume = {39},
number = {1},
abstract = {Baseball maintains one of the highest impact injury rates in all athletics. A principal causative factor is the "beanball," referring to a pitch thrown directly at a batter's head. Frequent morbidities elicited demand for the development of protective gear development in the 20th century. In this setting, Dr. Walter Dandy was commissioned to design a "protective cap" in 1941. His invention became widely adopted by professional baseball and inspired subsequent generations of batting helmets. As a baseball aficionado since his youth, Walter Dandy identified a natural partnership between baseball and medical practice for the reduction of beaning-related brain injuries. This history further supports the unique position of neurosurgeons to leverage clinical insights, inform innovation, and expand service to society. © AANS, 2015.},
keywords = {19th Century, 20th Century, Baseball, Baseball helmet, brain concussion, Head Protective Devices, Head trauma, Helmet, HISTORY, human, Humans, Injuries, Innovation, Male, middle aged, neurosurgeon, Neurosurgeons, Protective gear, traumatic brain injury, Walter dandy},
pubstate = {published},
tppubtype = {article}
}
Hwang, Sungjae; Ma, Lei; Kawata, Keisuke; Tierney, Ryan; Jeka, John J
Vestibular dysfunction after subconcussive head impact Journal Article
In: Journal of Neurotrauma, vol. 34, no. 1, pp. 8–15, 2017, ISBN: 0897-7151 1557-9042.
@article{Hwang2017,
title = {Vestibular dysfunction after subconcussive head impact},
author = {Hwang, Sungjae and Ma, Lei and Kawata, Keisuke and Tierney, Ryan and Jeka, John J},
doi = {10.1089/neu.2015.4238},
isbn = {0897-7151
1557-9042},
year = {2017},
date = {2017-01-01},
journal = {Journal of Neurotrauma},
volume = {34},
number = {1},
pages = {8--15},
publisher = {Mary Ann Liebert, Inc.},
address = {US},
abstract = {Current thinking views mild head impact (i.e., subconcussion) as an underrecognized phenomenon that has the ability to cause significant current and future detrimental neurological effects. Repeated mild impacts to the head, however, often display no observable behavioral deficits based on standard clinical tests, which may lack sensitivity. The current study investigates the effects of subconcussive impacts from soccer heading with innovative measures of vestibular function and walking stability in a pre- 0\textendash2 h, post- 24 h post-heading repeated measures design. The heading group (n = 10) executed 10 headers with soccer balls projected at a velocity of 25 mph (11.2 m/sec) over 10 min. Subjects were evaluated 24 h before, immediately after, and 24 h after soccer heading with: the modified Balance Error Scoring System (mBESS); a walking stability task with visual feedback of trunk movement; and galvanic vestibular stimulation (GVS) while standing with eyes closed on foam. A control group (n = 10) followed the same protocol with no heading. The results showed significant decrease in trunk angle, leg angle gain, and center of mass gain relative to GVS for the heading group compared with controls. Medial-lateral trunk orientation displacement and velocity during treadmill walking increased immediately after mild head impact for the heading group compared with controls. Controls showed an improvement in mBESS scores over time, indicating a learning effect, which was not observed with the heading group. These results suggest that mild head impact leads to a transient dysfunction in vestibular processing, which deters walking stability during task performance. (PsycINFO Database Record (c) 2017 APA, all rights reserved)},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Wojtowicz, M; Iverson, G L; Silverberg, N D; Mannix, R; Zafonte, R; Maxwell, B; Berkner, P D
Consistency of Self-Reported Concussion History in Adolescent Athletes Journal Article
In: Journal of Neurotrauma, vol. 34, no. 2, pp. 322–327, 2017.
@article{Wojtowicz2017,
title = {Consistency of Self-Reported Concussion History in Adolescent Athletes},
author = {Wojtowicz, M and Iverson, G L and Silverberg, N D and Mannix, R and Zafonte, R and Maxwell, B and Berkner, P D},
doi = {10.1089/neu.2016.4412},
year = {2017},
date = {2017-01-01},
journal = {Journal of Neurotrauma},
volume = {34},
number = {2},
pages = {322--327},
abstract = {Relying on self-reported concussion injury history is common in both clinical care and research. However, young athletes may not provide consistent medical information. To date, little is known about the reliability of self-reported concussion history in high school students. This study examined whether student athletes reported their lifetime history of concussions consistently over time. Self-reported concussion history was examined in 4792 student athletes (ages 13-18) from Maine who completed a preseason health survey on two occasions (median re-test interval = 23.7 months; standard deviation = 7.3; interquartile range = 12.4-24.5). Consistency of self-reported concussion history was determined by differences in the number of concussions reported during the second survey. Inconsistent concussion history was defined primarily by a decrease in the number of lifetime concussions reported at the second testing, compared with at the first testing. The majority of the sample (80.3%) reported no change in the number of concussions between the two baseline assessments. A minority (15.9%; n = 763) reported more concussions during the second assessment. Only 3.8% (n = 181) of student athletes provided inconsistent concussion histories, defined as fewer concussions at the second assessment. Boys provided inconsistent concussion histories a little more frequently, compared with girls (5.3% and 2.0%, respectively; p \< 0.001). Similarly, athletes with self-reported attention-deficit hyperactivity disorder (ADHD) provided inconsistent concussion histories somewhat more frequently, compared with those without ADHD (7.8% and 3.5%, respectively; p \< 0.001). Of the athletes with inconsistent concussion histories, greater degree of inconsistency was associated with a greater number of concussions initially reported at baseline (rs = 0.54; p \< 0.001). Only a small proportion of student athletes provided inconsistent concussion histories. Male gender, ADHD, and greater number of baseline concussions were significantly associated with inconsistency in reporting. Overall, these findings suggest that student athletes are quite consistent when reporting their concussion history when surveyed twice during high school. Copyright © 2017, Mary Ann Liebert, Inc. 2017.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Oliver, J M; Jones, M T; Kirk, K M; Gable, D A; Repshas, J T; Johnson, T A; Andréasson, U; Norgren, N; Blennow, K; Zetterberg, H
Serum Neurofilament Light in American Football Athletes over the Course of a Season Journal Article
In: Journal of Neurotrauma, vol. 33, no. 19, pp. 1784–1789, 2016.
@article{Oliver2016,
title = {Serum Neurofilament Light in American Football Athletes over the Course of a Season},
author = {Oliver, J M and Jones, M T and Kirk, K M and Gable, D A and Repshas, J T and Johnson, T A and Andr\'{e}asson, U and Norgren, N and Blennow, K and Zetterberg, H},
doi = {10.1089/neu.2015.4295},
year = {2016},
date = {2016-01-01},
journal = {Journal of Neurotrauma},
volume = {33},
number = {19},
pages = {1784--1789},
abstract = {Despite being underreported, American football boasts the highest incidence of concussion among all team sports, likely due to exposure to head impacts that vary in number and magnitude over the season. This study compared a biological marker of head trauma in American football athletes with non-contact sport athletes and examined changes over the course of a season. Baseline serum neurofilament light polypeptide (NFL) was measured after 9 weeks of no contact and compared with a non-contact sport. Serum NFL was then measured over the course of the entire season at eight time-points coincident with expected changes in likelihood of increased head impacts. Data were compared between starters (n = 11) and non-starters (n = 9). Compared with non-starters (mean ± standard deviation) (7.30 ± 3.57 pg•mL-1) and controls (6.75 ± 1.68 pg•mL-1), serum NFL in starters (8.45 ± 5.90 pg•mL-1) was higher at baseline (mean difference; ±90% confidence interval) (1.69; ± 1.96 pg•mL-1 and 1.15; ± 1.4 pg•mL-1, respectively). Over the course of the season, an increase (effect size [ES] = 1.8; p \< 0.001) was observed post-camp relative to baseline (1.52 ± 1.18 pg•mL-1), which remained elevated until conference play, when a second increase was observed (ES = 2.6; p = 0.008) over baseline (4.82 ± 2.64 pg•mL-1). A lack of change in non-starters resulted in substantial differences between starters and non-starters over the course of the season. These data suggest that a season of collegiate American football is associated with elevations in serum NFL, which is indicative of axonal injury, as a result of head impacts. Copyright © 2016, Mary Ann Liebert, Inc.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Oliver, J M; Jones, M T; Kirk, K M; Gable, D A; Repshas, J T; Johnson, T A; Andréasson, U; Norgren, N; Blennow, K; Zetterberg, H
Effect of docosahexaenoic acid on a biomarker of head trauma in American Football Journal Article
In: Medicine & Science in Sports & Exercise, vol. 48, no. 6, pp. 974–982, 2016.
@article{Oliver2016a,
title = {Effect of docosahexaenoic acid on a biomarker of head trauma in American Football},
author = {Oliver, J M and Jones, M T and Kirk, K M and Gable, D A and Repshas, J T and Johnson, T A and Andr\'{e}asson, U and Norgren, N and Blennow, K and Zetterberg, H},
doi = {10.1249/MSS.0000000000000875},
year = {2016},
date = {2016-01-01},
journal = {Medicine \& Science in Sports \& Exercise},
volume = {48},
number = {6},
pages = {974--982},
abstract = {Purpose American football athletes are exposed to subconcussive impacts over the course of the season resulting in elevations in serum neurofilament light (NFL), a biomarker of axonal injury. Docosahexaenoic acid (DHA) has been reported to reduce axonal trauma associated with traumatic brain injury in rodent models. However, the optimal dose in American football athletes is unknown. This study examined the effect of differing doses of DHA on serum NFL over the course of a season of American football. Methods In a randomized, double-blind, placebo-controlled, parallel design, 81 National Collegiate Athletic Association Division I American football athletes were assigned to ingest either 2, 4, 6 g·d -1 of DHA or placebo. Blood was sampled at specific times over the course of 189 d, coincident with changes in intensity, hours of contact, and likely changes in head impacts. Standardized magnitude-based inference was used to define outcomes. Results DHA supplementation increased plasma DHA in a dose-dependent manner (2 g·d -1: mean difference from baseline; ±90% CL; 2 g·d -1: 1.3; ±0.6; 4 g·d -1: 1.6; ±0.7%; 6 g·d -1: 2.8; ±1.2%). Serum NFL increased to a greater extent in starters (area under the curve, 1995 ± 1383 pg·mL -1) versus nonstarters (1398 ± 581 pg·mL -1; P = 0.024). Irrespective of dose, supplemental DHA likely attenuated serum NFL coincident with increases in serum NFL by likely small and moderate magnitude (effect size = 0.4-0.7). Conclusions Findings from this study, the first large-scale study examining potential prophylactic use of DHA in American football athletes, include identification of optimal dose of DHA, suggesting a neuroprotective effect of DHA supplementation. © 2016 by the American College of Sports Medicine.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Brewster, R; Bi, W L; Smith, T R; Gormley, W B; Dunn, I F; Laws Jr., E R
The neurosurgeon as baseball fan and inventor: Walter Dandy and the batter's helmet Journal Article
In: Neurosurgical Focus, vol. 39, no. 1, 2015.
@article{Brewster2015,
title = {The neurosurgeon as baseball fan and inventor: Walter Dandy and the batter's helmet},
author = {Brewster, R and Bi, W L and Smith, T R and Gormley, W B and Dunn, I F and {Laws Jr.}, E R},
doi = {10.3171/2015.3.FOCUS1552},
year = {2015},
date = {2015-01-01},
journal = {Neurosurgical Focus},
volume = {39},
number = {1},
abstract = {Baseball maintains one of the highest impact injury rates in all athletics. A principal causative factor is the "beanball," referring to a pitch thrown directly at a batter's head. Frequent morbidities elicited demand for the development of protective gear development in the 20th century. In this setting, Dr. Walter Dandy was commissioned to design a "protective cap" in 1941. His invention became widely adopted by professional baseball and inspired subsequent generations of batting helmets. As a baseball aficionado since his youth, Walter Dandy identified a natural partnership between baseball and medical practice for the reduction of beaning-related brain injuries. This history further supports the unique position of neurosurgeons to leverage clinical insights, inform innovation, and expand service to society. © AANS, 2015.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Hwang, Sungjae; Ma, Lei; Kawata, Keisuke; Tierney, Ryan; Jeka, John J
Vestibular dysfunction after subconcussive head impact Journal Article
In: Journal of Neurotrauma, vol. 34, no. 1, pp. 8–15, 2017, ISBN: 0897-7151 1557-9042.
Abstract | Links | BibTeX | Tags: 2017, BEHAVIORAL assessment, Behavioral assessments, Head trauma, Human studies, Outcome measures, Sensory Feedback, sensory function, Soccer, traumatic brain injury
@article{Hwang2017,
title = {Vestibular dysfunction after subconcussive head impact},
author = {Hwang, Sungjae and Ma, Lei and Kawata, Keisuke and Tierney, Ryan and Jeka, John J},
doi = {10.1089/neu.2015.4238},
isbn = {0897-7151
1557-9042},
year = {2017},
date = {2017-01-01},
journal = {Journal of Neurotrauma},
volume = {34},
number = {1},
pages = {8--15},
publisher = {Mary Ann Liebert, Inc.},
address = {US},
abstract = {Current thinking views mild head impact (i.e., subconcussion) as an underrecognized phenomenon that has the ability to cause significant current and future detrimental neurological effects. Repeated mild impacts to the head, however, often display no observable behavioral deficits based on standard clinical tests, which may lack sensitivity. The current study investigates the effects of subconcussive impacts from soccer heading with innovative measures of vestibular function and walking stability in a pre- 0\textendash2 h, post- 24 h post-heading repeated measures design. The heading group (n = 10) executed 10 headers with soccer balls projected at a velocity of 25 mph (11.2 m/sec) over 10 min. Subjects were evaluated 24 h before, immediately after, and 24 h after soccer heading with: the modified Balance Error Scoring System (mBESS); a walking stability task with visual feedback of trunk movement; and galvanic vestibular stimulation (GVS) while standing with eyes closed on foam. A control group (n = 10) followed the same protocol with no heading. The results showed significant decrease in trunk angle, leg angle gain, and center of mass gain relative to GVS for the heading group compared with controls. Medial-lateral trunk orientation displacement and velocity during treadmill walking increased immediately after mild head impact for the heading group compared with controls. Controls showed an improvement in mBESS scores over time, indicating a learning effect, which was not observed with the heading group. These results suggest that mild head impact leads to a transient dysfunction in vestibular processing, which deters walking stability during task performance. (PsycINFO Database Record (c) 2017 APA, all rights reserved)},
keywords = {2017, BEHAVIORAL assessment, Behavioral assessments, Head trauma, Human studies, Outcome measures, Sensory Feedback, sensory function, Soccer, traumatic brain injury},
pubstate = {published},
tppubtype = {article}
}
Wojtowicz, M; Iverson, G L; Silverberg, N D; Mannix, R; Zafonte, R; Maxwell, B; Berkner, P D
Consistency of Self-Reported Concussion History in Adolescent Athletes Journal Article
In: Journal of Neurotrauma, vol. 34, no. 2, pp. 322–327, 2017.
Abstract | Links | BibTeX | Tags: assessment tools, Head trauma, pediatric brain injury
@article{Wojtowicz2017,
title = {Consistency of Self-Reported Concussion History in Adolescent Athletes},
author = {Wojtowicz, M and Iverson, G L and Silverberg, N D and Mannix, R and Zafonte, R and Maxwell, B and Berkner, P D},
doi = {10.1089/neu.2016.4412},
year = {2017},
date = {2017-01-01},
journal = {Journal of Neurotrauma},
volume = {34},
number = {2},
pages = {322--327},
abstract = {Relying on self-reported concussion injury history is common in both clinical care and research. However, young athletes may not provide consistent medical information. To date, little is known about the reliability of self-reported concussion history in high school students. This study examined whether student athletes reported their lifetime history of concussions consistently over time. Self-reported concussion history was examined in 4792 student athletes (ages 13-18) from Maine who completed a preseason health survey on two occasions (median re-test interval = 23.7 months; standard deviation = 7.3; interquartile range = 12.4-24.5). Consistency of self-reported concussion history was determined by differences in the number of concussions reported during the second survey. Inconsistent concussion history was defined primarily by a decrease in the number of lifetime concussions reported at the second testing, compared with at the first testing. The majority of the sample (80.3%) reported no change in the number of concussions between the two baseline assessments. A minority (15.9%; n = 763) reported more concussions during the second assessment. Only 3.8% (n = 181) of student athletes provided inconsistent concussion histories, defined as fewer concussions at the second assessment. Boys provided inconsistent concussion histories a little more frequently, compared with girls (5.3% and 2.0%, respectively; p \< 0.001). Similarly, athletes with self-reported attention-deficit hyperactivity disorder (ADHD) provided inconsistent concussion histories somewhat more frequently, compared with those without ADHD (7.8% and 3.5%, respectively; p \< 0.001). Of the athletes with inconsistent concussion histories, greater degree of inconsistency was associated with a greater number of concussions initially reported at baseline (rs = 0.54; p \< 0.001). Only a small proportion of student athletes provided inconsistent concussion histories. Male gender, ADHD, and greater number of baseline concussions were significantly associated with inconsistency in reporting. Overall, these findings suggest that student athletes are quite consistent when reporting their concussion history when surveyed twice during high school. Copyright © 2017, Mary Ann Liebert, Inc. 2017.},
keywords = {assessment tools, Head trauma, pediatric brain injury},
pubstate = {published},
tppubtype = {article}
}
Oliver, J M; Jones, M T; Kirk, K M; Gable, D A; Repshas, J T; Johnson, T A; Andréasson, U; Norgren, N; Blennow, K; Zetterberg, H
Serum Neurofilament Light in American Football Athletes over the Course of a Season Journal Article
In: Journal of Neurotrauma, vol. 33, no. 19, pp. 1784–1789, 2016.
Abstract | Links | BibTeX | Tags: adult brain injury, axonal injury, Biomarkers, Head trauma, traumatic brain injury
@article{Oliver2016,
title = {Serum Neurofilament Light in American Football Athletes over the Course of a Season},
author = {Oliver, J M and Jones, M T and Kirk, K M and Gable, D A and Repshas, J T and Johnson, T A and Andr\'{e}asson, U and Norgren, N and Blennow, K and Zetterberg, H},
doi = {10.1089/neu.2015.4295},
year = {2016},
date = {2016-01-01},
journal = {Journal of Neurotrauma},
volume = {33},
number = {19},
pages = {1784--1789},
abstract = {Despite being underreported, American football boasts the highest incidence of concussion among all team sports, likely due to exposure to head impacts that vary in number and magnitude over the season. This study compared a biological marker of head trauma in American football athletes with non-contact sport athletes and examined changes over the course of a season. Baseline serum neurofilament light polypeptide (NFL) was measured after 9 weeks of no contact and compared with a non-contact sport. Serum NFL was then measured over the course of the entire season at eight time-points coincident with expected changes in likelihood of increased head impacts. Data were compared between starters (n = 11) and non-starters (n = 9). Compared with non-starters (mean ± standard deviation) (7.30 ± 3.57 pg•mL-1) and controls (6.75 ± 1.68 pg•mL-1), serum NFL in starters (8.45 ± 5.90 pg•mL-1) was higher at baseline (mean difference; ±90% confidence interval) (1.69; ± 1.96 pg•mL-1 and 1.15; ± 1.4 pg•mL-1, respectively). Over the course of the season, an increase (effect size [ES] = 1.8; p \< 0.001) was observed post-camp relative to baseline (1.52 ± 1.18 pg•mL-1), which remained elevated until conference play, when a second increase was observed (ES = 2.6; p = 0.008) over baseline (4.82 ± 2.64 pg•mL-1). A lack of change in non-starters resulted in substantial differences between starters and non-starters over the course of the season. These data suggest that a season of collegiate American football is associated with elevations in serum NFL, which is indicative of axonal injury, as a result of head impacts. Copyright © 2016, Mary Ann Liebert, Inc.},
keywords = {adult brain injury, axonal injury, Biomarkers, Head trauma, traumatic brain injury},
pubstate = {published},
tppubtype = {article}
}
Oliver, J M; Jones, M T; Kirk, K M; Gable, D A; Repshas, J T; Johnson, T A; Andréasson, U; Norgren, N; Blennow, K; Zetterberg, H
Effect of docosahexaenoic acid on a biomarker of head trauma in American Football Journal Article
In: Medicine & Science in Sports & Exercise, vol. 48, no. 6, pp. 974–982, 2016.
Abstract | Links | BibTeX | Tags: Concussion, DHA, Head trauma, NEUROFILAMENT LIGHT
@article{Oliver2016a,
title = {Effect of docosahexaenoic acid on a biomarker of head trauma in American Football},
author = {Oliver, J M and Jones, M T and Kirk, K M and Gable, D A and Repshas, J T and Johnson, T A and Andr\'{e}asson, U and Norgren, N and Blennow, K and Zetterberg, H},
doi = {10.1249/MSS.0000000000000875},
year = {2016},
date = {2016-01-01},
journal = {Medicine \& Science in Sports \& Exercise},
volume = {48},
number = {6},
pages = {974--982},
abstract = {Purpose American football athletes are exposed to subconcussive impacts over the course of the season resulting in elevations in serum neurofilament light (NFL), a biomarker of axonal injury. Docosahexaenoic acid (DHA) has been reported to reduce axonal trauma associated with traumatic brain injury in rodent models. However, the optimal dose in American football athletes is unknown. This study examined the effect of differing doses of DHA on serum NFL over the course of a season of American football. Methods In a randomized, double-blind, placebo-controlled, parallel design, 81 National Collegiate Athletic Association Division I American football athletes were assigned to ingest either 2, 4, 6 g·d -1 of DHA or placebo. Blood was sampled at specific times over the course of 189 d, coincident with changes in intensity, hours of contact, and likely changes in head impacts. Standardized magnitude-based inference was used to define outcomes. Results DHA supplementation increased plasma DHA in a dose-dependent manner (2 g·d -1: mean difference from baseline; ±90% CL; 2 g·d -1: 1.3; ±0.6; 4 g·d -1: 1.6; ±0.7%; 6 g·d -1: 2.8; ±1.2%). Serum NFL increased to a greater extent in starters (area under the curve, 1995 ± 1383 pg·mL -1) versus nonstarters (1398 ± 581 pg·mL -1; P = 0.024). Irrespective of dose, supplemental DHA likely attenuated serum NFL coincident with increases in serum NFL by likely small and moderate magnitude (effect size = 0.4-0.7). Conclusions Findings from this study, the first large-scale study examining potential prophylactic use of DHA in American football athletes, include identification of optimal dose of DHA, suggesting a neuroprotective effect of DHA supplementation. © 2016 by the American College of Sports Medicine.},
keywords = {Concussion, DHA, Head trauma, NEUROFILAMENT LIGHT},
pubstate = {published},
tppubtype = {article}
}
Brewster, R; Bi, W L; Smith, T R; Gormley, W B; Dunn, I F; Laws Jr., E R
The neurosurgeon as baseball fan and inventor: Walter Dandy and the batter's helmet Journal Article
In: Neurosurgical Focus, vol. 39, no. 1, 2015.
Abstract | Links | BibTeX | Tags: 19th Century, 20th Century, Baseball, Baseball helmet, brain concussion, Head Protective Devices, Head trauma, Helmet, HISTORY, human, Humans, Injuries, Innovation, Male, middle aged, neurosurgeon, Neurosurgeons, Protective gear, traumatic brain injury, Walter dandy
@article{Brewster2015,
title = {The neurosurgeon as baseball fan and inventor: Walter Dandy and the batter's helmet},
author = {Brewster, R and Bi, W L and Smith, T R and Gormley, W B and Dunn, I F and {Laws Jr.}, E R},
doi = {10.3171/2015.3.FOCUS1552},
year = {2015},
date = {2015-01-01},
journal = {Neurosurgical Focus},
volume = {39},
number = {1},
abstract = {Baseball maintains one of the highest impact injury rates in all athletics. A principal causative factor is the "beanball," referring to a pitch thrown directly at a batter's head. Frequent morbidities elicited demand for the development of protective gear development in the 20th century. In this setting, Dr. Walter Dandy was commissioned to design a "protective cap" in 1941. His invention became widely adopted by professional baseball and inspired subsequent generations of batting helmets. As a baseball aficionado since his youth, Walter Dandy identified a natural partnership between baseball and medical practice for the reduction of beaning-related brain injuries. This history further supports the unique position of neurosurgeons to leverage clinical insights, inform innovation, and expand service to society. © AANS, 2015.},
keywords = {19th Century, 20th Century, Baseball, Baseball helmet, brain concussion, Head Protective Devices, Head trauma, Helmet, HISTORY, human, Humans, Injuries, Innovation, Male, middle aged, neurosurgeon, Neurosurgeons, Protective gear, traumatic brain injury, Walter dandy},
pubstate = {published},
tppubtype = {article}
}