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Shibukawa K, Hoshikawa Y. Decrease in aerial challenges after revision of goal kick rules in Japan Professional Soccer League: explorative study of the possibility of a risk reduction for head injury, concussion, and brain damage by a rule revision. SCI MED FOOTBALL 2024; 8:15-20. [PMID: 36315233 DOI: 10.1080/24733938.2022.2142274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/26/2022] [Indexed: 11/05/2022]
Abstract
In 2019, FIFA revised the goal kick (GLK) rule such that a GLK could be performed even if the kicker had teammates in the penalty area. This study aimed to examine whether the rule revision reduced the frequency of aerial challenge (AC) and long GLKs (LGLKs), which are risk factors for head injury and concussion in soccer. We analyzed all official league matches (306 matches/season) of the Japan Professional Soccer League 1st Division before (2018 season) and after the rule revision (2020 season). The analysis categorized GLKs into short GLKs (SGLKs) and LGLKs, depending on the GLK distance, and included the frequency and causes of AC, in each match following a GLK, which were compared between the 2018 and 2020 seasons. The average number of LGLKs per match in the 2020 season (8.85) decreased compared to that in the 2018 season (14.20). Additionally, for ACs following a GLK, the frequency of ACs decreased from 6.08 to 3.92 per match. Meanwhile, the frequency of LGLKs tended to increase toward the end of the first and second halves in matches. The results of this study revealed that the 2019 GLK rule revision reduced the number of LGLKs and ACs.
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Affiliation(s)
- Kenichi Shibukawa
- Sports & Health Sciences Lab, Faculty of Sciences, Toho University, Chiba, Japan
| | - Yoshihiro Hoshikawa
- Department of Sports Science, Japan Women's College of Physical Education, Tokyo, Japan
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2
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Tierney G, Rowson S, Gellner R, Allan D, Iqbal S, Biglarbeigi P, Tooby J, Woodward J, Payam AF. Head Exposure to Acceleration Database in Sport (HEADSport): a kinematic signal processing method to enable instrumented mouthguard (iMG) field-based inter-study comparisons. BMJ Open Sport Exerc Med 2024; 10:e001758. [PMID: 38304714 PMCID: PMC10831454 DOI: 10.1136/bmjsem-2023-001758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/18/2023] [Indexed: 02/03/2024] Open
Abstract
Objective Instrumented mouthguard (iMG) systems use different signal processing approaches limiting field-based inter-study comparisons, especially when artefacts are present in the signal. The objective of this study was to assess the frequency content and characteristics of head kinematic signals from head impact reconstruction laboratory and field-based environments to develop an artefact attenuation filtering method (HEADSport filter method). Methods Laboratory impacts (n=72) on a test-dummy headform ranging from 25 to 150 g were conducted and 126 rugby union players were equipped with iMGs for 209 player-matches. Power spectral density (PSD) characteristics of the laboratory impacts and on-field head acceleration events (HAEs) (n=5694) such as the 95th percentile cumulative sum PSD frequency were used to develop the HEADSport method. The HEADSport filter method was compared with two other common filtering approaches (Butterworth-200Hz and CFC180 filter) through signal-to-noise ratio (SNR) and mixed linear effects models for laboratory and on-field events, respectively. Results The HEADSport filter method produced marginally higher SNR than the Butterworth-200Hz and CFC180 filter and on-field peak linear acceleration (PLA) and peak angular acceleration (PAA) values within the magnitude range tested in the laboratory. Median PLA and PAA (and outlier values) were higher for the CFC180 filter than the Butterworth-200Hz and HEADSport filter method (p<0.01). Conclusion The HEADSport filter method could enable iMG field-based inter-study comparisons and is openly available at https://github.com/GTBiomech/HEADSport-Filter-Method.
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Affiliation(s)
- Gregory Tierney
- Nanotechnology and Integrated Bioengineering Centre (NIBEC), Ulster University, Belfast, UK
- Sport and Exercise Sciences Research Institute, Ulster University, Belfast, UK
| | - Steven Rowson
- Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, Virginia, USA
| | - Ryan Gellner
- Biomedical Engineering and Mechanics, Virginia Tech, Blacksburg, Virginia, USA
| | - David Allan
- Nanotechnology and Integrated Bioengineering Centre (NIBEC), Ulster University, Belfast, UK
- Sport and Exercise Sciences Research Institute, Ulster University, Belfast, UK
| | - Sadaf Iqbal
- Sport and Exercise Sciences Research Institute, Ulster University, Belfast, UK
| | | | - James Tooby
- Carnegie Applied Rugby Research (CARR) Centre, Carnegie School of Sport, Leeds Beckett University, Leeds, UK
| | - James Woodward
- Sport and Exercise Sciences Research Institute, Ulster University, Belfast, UK
| | - Amir Farokh Payam
- Nanotechnology and Integrated Bioengineering Centre (NIBEC), Ulster University, Belfast, UK
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Hageman G, Hageman I, Nihom J. Chronic Traumatic Encephalopathy in Soccer Players: Review of 14 Cases. Clin J Sport Med 2024; 34:69-80. [PMID: 37403989 DOI: 10.1097/jsm.0000000000001174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 05/22/2023] [Indexed: 07/06/2023]
Abstract
OBJECTIVE Exposure to repetitive sports-related concussions or (sub)concussive head trauma may lead to chronic traumatic encephalopathy (CTE). Which impact (heading or concussion) poses the greatest risk of CTE development in soccer players? DESIGN Narrative review. SETTING Teaching hospital and University of Applied sciences. PATIENTS A literature search (PubMed) was conducted for neuropathologic studies in the period 2005-December 2022, investigating soccer players with dementia and a CTE diagnosis, limited to English language publications. 210 papers were selected for final inclusion, of which 7 papers described 14 soccer players. ASSESSMENT Magnetic resonance imaging studies in soccer players show that lifetime estimates of heading numbers are inversely correlated with cortical thickness, grey matter volume, and density of the anterior temporal cortex. Using diffusion tensor imaging-magnetic resonance imaging, higher frequency of headings-particularly with rotational accelerations-are associated with impaired white matter integrity. Serum neurofilament light protein is elevated after heading. MAIN OUTCOME MEASURES Chronic traumatic encephalopathy pathology, history of concussion, heading frequency. RESULTS In 10 of 14 soccer players, CTE was the primary diagnosis. In 4 cases, other dementia types formed the primary diagnosis and CTE pathology was a concomitant finding. Remarkably, 6 of the 14 cases had no history of concussion, suggesting that frequent heading may be a risk for CTE in patients without symptomatic concussion. Rule changes in heading duels, management of concussion during the game, and limiting the number of high force headers during training are discussed. CONCLUSIONS Data suggest that heading frequency and concussions are associated with higher risk of developing CTE in (retired) soccer players. However based on this review of only 14 players, questions persist as to whether or not heading is a risk factor for CTE or long-term cognitive decline.
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Affiliation(s)
- Gerard Hageman
- Department of Neurology, Medisch Spectrum Twente, Hospital Enschede, Enschede, the Netherlands; and
| | - Ivar Hageman
- Saxion University of Applied Sciences, Enschede, the Netherlands
| | - Jik Nihom
- Department of Neurology, Medisch Spectrum Twente, Hospital Enschede, Enschede, the Netherlands; and
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Peek K, Duffield R, Cairns R, Jones M, Meyer T, McCall A, Oxenham V. Where are We Headed? Evidence to Inform Future Football Heading Guidelines. Sports Med 2023; 53:1335-1358. [PMID: 37285067 PMCID: PMC10289964 DOI: 10.1007/s40279-023-01852-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/13/2023] [Indexed: 06/08/2023]
Abstract
Given the scientific and public concern regarding the short-, medium- and long-term consequences of heading on brain health, being proactive about developing and implementing guidelines that help reduce the burden (volume, impact magnitude and injury risk) of heading in young and beginner players appears justified. This narrative review explores the evidence underpinning strategies that could be incorporated into future heading guidelines to reduce heading burden in players across all levels of football. A four-step search strategy was utilised to identify all data-based papers related to heading in football. Eligibility criteria for inclusion were: (1) original data, (2) study population included football players, (3) outcome measures included one or more of the following: number of headers, measurement of head acceleration during heading, or head/brain injury incidence, and (4) published in English or English translation available. In total, 58 papers were included that outlined strategies based on (1) game or team development, (2) player skill development and (3) equipment. In particular, greater emphasis existed for small-sided games (particularly in young players) where fewer headers are observed when compared with the conventional 11 versus 11 game, as well as reducing headers from goal kicks and corners. Evidence also existed for developing a heading coaching framework that focusses on technical proficiency as well as neuromuscular neck exercises integrated into general injury reduction exercise programs, enforcement of rules related to deliberate head contact and using lower-pressure match and training balls. To mitigate potential risks of heading on brain health, a number of pragmatic strategies have been examined in scientific studies and may be considered as part of future heading guidelines.
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Affiliation(s)
- Kerry Peek
- Discipline of Physiotherapy, School of Health Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW Australia
| | - Rob Duffield
- School of Sport, Exercsie & Rehabilitation, Faculty of Health, University of Technology Sydney, Sydney, NSW Australia
- Football Australia, Sydney, NSW Australia
| | - Ross Cairns
- Newcastle Sports Medicine, Warners Bay, NSW Australia
- School of Medicine and Public Health, The University of Newcastle, Newcastle, Australia
| | - Mark Jones
- Football Australia, Sydney, NSW Australia
| | - Tim Meyer
- Institute of Sports and Preventive Medicine, Saarland University, Saarbrücken, Germany
| | - Alan McCall
- School of Sport, Exercsie & Rehabilitation, Faculty of Health, University of Technology Sydney, Sydney, NSW Australia
- Football Australia, Sydney, NSW Australia
| | - Vincent Oxenham
- School of Psychological Sciences, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW Australia
- Department of Neuropsychology, Royal North Shore Hospital, Sydney, NSW Australia
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Parr JVV, Uiga L, Marshall B, Wood G. Soccer heading immediately alters brain function and brain-muscle communication. Front Hum Neurosci 2023; 17:1145700. [PMID: 37151902 PMCID: PMC10157247 DOI: 10.3389/fnhum.2023.1145700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 03/28/2023] [Indexed: 05/09/2023] Open
Abstract
Introduction There is growing evidence of a link between repetitive soccer heading and the increased incidence of neurodegenerative disease. Even a short bout of soccer heading has been shown to impair cognitive performance and disrupt movement control. However, a greater understanding of the mechanisms behind these immediate impairments is needed. The current study attempted to identify how a short bout of soccer heading alters brain function and brain-muscle communication during a movement task. Methods Sixty soccer players were exposed to either an acute bout (i.e., 20 balls thrown underarm) of soccer heading (n = 30) or a control condition where participants (n = 30) headed soccer balls in virtual reality (VR). Before and after heading, we measured cognitive performance on the King-Devick test, as well as electromyography (EMG), electroencephalography (EEG) and brain-muscle communication (i.e., corticomuscular coherence; CMC) during a force precision task. Results Following the heading protocol, the VR group improved their cognitive performance whereas the Heading group showed no change. Both groups displayed more precise force contractions at post-test. However, the VR group displayed elevated frontal theta activity and global increases in alpha and beta activity during the contraction task, whereas the Heading group did not. Contrary to our expectations, the Heading group displayed elevated CMC, whereas the VR group showed no change. Discussion Our findings indicate a short bout of soccer heading may impair cognitive function and disrupt the organization of efficient neural processes that typically accompany motor skill proficiency. Soccer heading also induced corticomuscular hyperconnectivity, which could represent compensatory brain-muscle communication and an inefficient allocation of increased task-related neuromuscular resources. These initial findings offer insights to the mechanisms behind the impairments experienced after a short bout of repetitive soccer heading.
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Affiliation(s)
- Johnny V. V. Parr
- Department of Sport and Exercise Sciences, Manchester Metropolitan University, Manchester, United Kingdom
- Institute of Sport, Manchester Metropolitan University, Manchester, United Kingdom
- *Correspondence: Johnny V. V. Parr,
| | - Liis Uiga
- Department of Sport and Exercise Sciences, Manchester Metropolitan University, Manchester, United Kingdom
- Institute of Sport, Manchester Metropolitan University, Manchester, United Kingdom
| | - Ben Marshall
- Department of Sport and Exercise Sciences, Manchester Metropolitan University, Manchester, United Kingdom
- Institute of Sport, Manchester Metropolitan University, Manchester, United Kingdom
| | - Greg Wood
- Department of Sport and Exercise Sciences, Manchester Metropolitan University, Manchester, United Kingdom
- Institute of Sport, Manchester Metropolitan University, Manchester, United Kingdom
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Porfido T, Caccese J, Gutt J, Wentworth C, Peek K, Bretzin AC, Esopenko C. A standardized method for quantifying and characterizing repetitive head impacts in soccer matches using video footage. SCI MED FOOTBALL 2022; 6:331-339. [DOI: 10.1080/24733938.2022.2056233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Tara Porfido
- School of Graduate Studies, Rutgers Biomedical and Health Sciences, Newark, NJ, 07107 USA
| | - Jaclyn Caccese
- School of Health and Rehabilitation Sciences, The Ohio State University College of Medicine, Columbus, OH, 43210 USA
| | - Jessica Gutt
- Department of Rehabilitation & Movement Sciences, School of Health Professions, Rutgers Biomedical and Health Sciences, Newark, NJ, 07107 USA
| | - Conor Wentworth
- Department of Rehabilitation & Movement Sciences, School of Health Professions, Rutgers Biomedical and Health Sciences, Newark, NJ, 07107 USA
| | - Kerry Peek
- Discipline of Physiotherapy, Sydney School of Health Sciences, The University of Sydney, Sydney, NSW 2006 Australia
| | - Abigail C Bretzin
- Penn Injury Science Center, Department of Biostatistics, Epidemiology, and Informatics, University of Pennsylvania, Philadelphia, PA, 19104 USA
| | - Carrie Esopenko
- Department of Rehabilitation & Movement Sciences, School of Health Professions, Rutgers Biomedical and Health Sciences, Newark, NJ, 07107 USA
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Ashton J, Coyles G, Malone JJ, Roberts JW. Immediate effects of an acute bout of repeated soccer heading on cognitive performance. SCI MED FOOTBALL 2022; 5:181-187. [PMID: 35077295 DOI: 10.1080/24733938.2020.1846769] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Purpose: There isgrowing concern surrounding the harmful effects of soccer heading on cognitive function. The present study aims to examine the immediate effects of heading.Methods: 30 recreational male soccer players were divided into three groups that undertook 20 consecutive headers with a soft (8.8 psi), hard (16.2 psi), or no (control) ball. A battery of neuropsychological tests was completed before and after heading: King-Devick, trail-making (TM) (A, B), digit span (DS) and spatial span (SS) (forward, backward).Results: Significant increase in the time (M = 4.44 s) and errors (M = 1.45) for the King-Devick test within the hard and soft groups, although there was no significant difference for TM-A and TM-B. Significant decline for SS forward within the hard and soft groups (M= -16%), although the declines for SS backward (M = -16%), DS forward (M= -23%) and DS backward (M = -25%) were present only for the hard group (ps <.05).Discussion: While outside of regular match-play, this study showed that heading negatively influenced one indicator of a suspected concussion (King-Devick), as well as working memory (DS, SS) that is essential for daily life. These findings contribute to the growing debate surrounding heading safety.
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Affiliation(s)
- Jake Ashton
- School of Health Sciences, Liverpool Hope University, Hope Park, Liverpool, UK, L16 9JD
| | - Ginny Coyles
- School of Health Sciences, Liverpool Hope University, Hope Park, Liverpool, UK, L16 9JD
| | - James J Malone
- School of Health Sciences, Liverpool Hope University, Hope Park, Liverpool, UK, L16 9JD
| | - James W Roberts
- School of Health Sciences, Liverpool Hope University, Hope Park, Liverpool, UK, L16 9JD
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Peek K, McKay M, Fu A, Meyer T, Oxenham V, Esopenko C, Caccese J, Andersen J. The effect of ball characteristics on head acceleration during purposeful heading in male and female youth football players. SCI MED FOOTBALL 2022; 5:195-203. [PMID: 35077287 DOI: 10.1080/24733938.2021.1897657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Objective: The objective of this cross-sectional study was to explore the effects of different ball types and characteristics on head acceleration during purposeful heading in youth football players. Methods: Experienced male and female players (n = 61) aged between 12-17 years completed heading trials with 4 different balls (Ball 1 mass 192 grams (g), pressure 5.0 pounds per square inch (psi); Ball 2 432 g, 5.0 psi; Ball 3 255 g, 5.0 psi; Ball 4 430 g, 10.5 psi) whilst wearing a head-mounted accelerometer and gyroscope. Balls 1, 2 and 4 were size 5 balls; Ball 3 was a size 4 ball.Results: Multivariate analysis of variance and post-hoc univariate analyses revealed a statistically significant difference between ball type and head acceleration during heading for both linear acceleration (adjusted R2 = 0.68; F = 140.90; p = <0.001) and angular velocity (adjusted R2 = 0.28; F = 26.52; p = <0.001). Ball 1 (lightest size 5 ball) and Ball 3 (size 4 ball) demonstrated linear head accelerations up to 59% lower (p = <0.01) when compared with Ball 4 (size 5 regulated match ball).Discussion: Head acceleration during purposeful heading is influenced by changes to ball pressure, ball size and/or ball mass. Changing ball characteristics, particularly in youth football training when heading is being taught, should be an easy strategy to implement.
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Affiliation(s)
- Kerry Peek
- Discipline of Physiotherapy, School of Health Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, Australia
| | - Marnee McKay
- Discipline of Physiotherapy, School of Health Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, Australia
| | - Allan Fu
- Discipline of Physiotherapy, School of Health Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, Australia
| | - Tim Meyer
- Institute of Sports and Preventive Medicine, Medical Faculty, Saarland University, Saarbrücken, Germany
| | - Vincent Oxenham
- Department of Psychology, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, Australia.,Department of Neurology, Royal North Shore Hospital, Sydney, Australia
| | - Carrie Esopenko
- Department of Rehabilitation and Movement Sciences, Rutgers Biomedical Health Sciences, Newark, USA
| | - Jaclyn Caccese
- School of Health and Rehabilitation Sciences, The Ohio State University College of Medicine, Columbus, USA
| | - Jordan Andersen
- School of Health Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, Australia
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Tierney G. Concussion biomechanics, head acceleration exposure and brain injury criteria in sport: a review. Sports Biomech 2021:1-29. [PMID: 34939531 DOI: 10.1080/14763141.2021.2016929] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 12/05/2021] [Indexed: 10/19/2022]
Abstract
There are mounting concerns surrounding the risk of neurodegenerative diseases and complications associated with concussion incidence and repetitive head acceleration events (HAE) in sport. The aim of this review is to provide an overview of concussion biomechanics, head acceleration exposure and brain injury criteria in sport. Rotational head motion appears to be the primary contributor to brain injury risk due to the unique mechanical properties of the brain and its location within the body. There is a growing evidence base of different biomechanical brain injury mechanisms, including those involving repetitive HAE. Historically, many studies on concussion biomechanics, head acceleration exposure and brain injury criteria in sport have been limited by validity of the biomechanical approaches undertaken. Biomechanical approaches such as instrumented mouthguards and subject-specific finite element (FE) brain models provide a unique opportunity to develop greater brain injury criteria and aid in on-field athlete removal. Implementing these approaches on a large-scale can gain insight into potential risk factors within sports and certain athletes/cohorts who sustain a greater number and/or severity of HAE throughout their playing career. These findings could play a key role in the development of concussion prevention strategies and techniques that mitigate the severity of HAE in sport.
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Affiliation(s)
- Gregory Tierney
- Sport and Exercise Sciences Research Institute, School of Sport, Faculty of Life and Health Sciences, Ulster University, Belfast, UK
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Cockerell OC, Iino Hayes N, Sylvester R. The neurological risks of playing association football. JRSM Open 2021; 12:20542704211055558. [PMID: 34824860 PMCID: PMC8609100 DOI: 10.1177/20542704211055558] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Aims: The present study aims to provide a narrative review of the literature
surrounding concussion and head injury in football and its clarity in
evaluating the risk of long-term neurological disease. Findings: Epidemiological studies have shown correlations between participation in
professional football and increased incidence of neurodegenerative disease
and there have been reports of chronic traumatic encephalopathy (CTE) in the
brains of former players in autopsy. These findings have been assumed by
some to be the result of repetitive brain injury from head injuries and/or
from heading the ball over a player's career. Data linking increased heading
exposure with dementia is conflicting, and studies are limited by the
reliance on retrospection and undocumented reports of concussion. It remains
unclear whether CTE is unique to sportsmen or a variant of dementia
pathology endemic in the population. Conclusions: Although logically appealing, there is no current evidence that heading is
the cause of neurodegeneration amongst footballers and risks should be
balanced by the protective mental and physical benefits of the sport.
Physicians have an important role in providing balanced views in this
emotive and controversial area.
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Affiliation(s)
- Oliver C Cockerell
- The London Clinic, London W1G 6HL, UK.,Queen Mary University of London, Mile End E1 4NS, UK
| | | | - Richard Sylvester
- National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK.,University College London, Bloomsbury WC1E 6BT, UK
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