1
|
Cao Y, Liu Y, Tang L, Jiang Z, Liu Z, Zhou L, Yang B. Quantitative assessment of brain injury and concussion induced by an unintentional soccer ball impact. Injury 2024; 55:111658. [PMID: 38879923 DOI: 10.1016/j.injury.2024.111658] [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] [Received: 03/18/2024] [Revised: 05/21/2024] [Accepted: 06/03/2024] [Indexed: 06/18/2024]
Abstract
BACKGROUND Accidental impact on a player's head by a powerful soccer ball may lead to brain injuries and concussions during games. It is crucial to assess these injuries promptly and accurately on the field. However, it is challenging for referees, coaches, and even players themselves to accurately recognize potential injuries and concussions following such impacts. Therefore, it is necessary to establish a list of minimum ball velocity thresholds that can result in concussions at different impact locations on the head. Additionally, it is important to identify the affected brain regions responsible for impairments in brain function and potential clinical symptoms. METHODS By using a full human finite element model, dynamic responses and brain injuries caused by unintentional soccer ball impacts on six distinct head locations (forehead, tempus, crown, occiput, face, and jaw) at varying ball velocities (10, 15, 20, 25, 30, 35, 40, and 60 m/s) were simulated and investigated. Intracranial pressure, Von-Mises stress, and first principal strain were analyzed, the ball velocity thresholds resulting in concussions at different impact locations were evaluated, and the damage evolution patterns in the brain tissue were analyzed. RESULTS The impact on the occiput is most susceptible to induce brain injuries compared to all other impact locations. For a conservative assessment, the risk of concussion is present once the soccer ball reaches 17.2 m/s in a frontal impact, 16.6 m/s in a parietal impact, 14.0 m/s in an occipital impact, 17.8 m/s in a temporal impact, 18.5 m/s in a facial impact or 19.2 m/s in a mandibular impact. The brain exhibits the most significant dynamic responses during the initial 10-20 ms, and the damaged regions are primarily concentrated in the medial temporal lobe and the corpus callosum, potentially causing impairments in brain functions. CONCLUSIONS This work offers a framework for quantitatively assessing brain injuries and concussions induced by an unintentional soccer ball impact. Determining the ball velocity thresholds at various impact locations provides a benchmark for evaluating the risks of concussion. The examination of brain tissue damage evolution introduces a novel approach to linking biomechanical responses with possible clinical symptoms.
Collapse
Affiliation(s)
- Yangjian Cao
- School of Civil Engineering and Transportation, State Key Laboratory of Subtropical Building and Urban Science, South China University of Technology, Guangzhou 510640, China
| | - Yiping Liu
- School of Civil Engineering and Transportation, State Key Laboratory of Subtropical Building and Urban Science, South China University of Technology, Guangzhou 510640, China.
| | - Liqun Tang
- School of Civil Engineering and Transportation, State Key Laboratory of Subtropical Building and Urban Science, South China University of Technology, Guangzhou 510640, China
| | - Zhenyu Jiang
- School of Civil Engineering and Transportation, State Key Laboratory of Subtropical Building and Urban Science, South China University of Technology, Guangzhou 510640, China
| | - Zejia Liu
- School of Civil Engineering and Transportation, State Key Laboratory of Subtropical Building and Urban Science, South China University of Technology, Guangzhou 510640, China
| | - Licheng Zhou
- School of Civil Engineering and Transportation, State Key Laboratory of Subtropical Building and Urban Science, South China University of Technology, Guangzhou 510640, China
| | - Bao Yang
- School of Civil Engineering and Transportation, State Key Laboratory of Subtropical Building and Urban Science, South China University of Technology, Guangzhou 510640, China
| |
Collapse
|
2
|
Lin CL, DeMessie B, Ye K, Hu S, Lipton ML. Neck strength alone does not mitigate adverse associations of soccer heading with cognitive performance in adult amateur players. PLoS One 2024; 19:e0302463. [PMID: 38753699 PMCID: PMC11098408 DOI: 10.1371/journal.pone.0302463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 04/03/2024] [Indexed: 05/18/2024] Open
Abstract
OBJECTIVES Soccer heading is adversely associated with neurocognitive performance, but whether greater neck strength or anthropometrics mitigates these outcomes is controversial. Here, we examine the effect of neck strength or anthropometrics on associations of soccer heading with neurocognitive outcomes in a large cohort of adult amateur players. METHODS 380 adult amateur league soccer players underwent standardized measurement of neck strength (forward flexion, extension, left lateral flexion, right lateral flexion) and head/neck anthropometric measures (head circumference, neck length, neck circumference and neck volume). Participants were assessed for heading (HeadCount) and cognitive performance (Cogstate) on up to 7 visits over a period of two years. Principal components analysis (PCA) was performed on 8 neck strength and anthropometric measures. We used generalized estimating equations to test the moderation effect of each of the three PCs on 8 previously identified adverse associations of 2-week and 12-month heading estimates with cognitive performance (psychomotor speed, immediate verbal recall, verbal episodic memory, attention, working memory) and of unintentional head impacts on moderate to severe central nervous system symptoms. RESULTS 3 principal components (PC's) account for 80% of the variance in the PCA. In men, PC1 represents head/neck anthropometric measures, PC2 represents neck strength measures, and PC3 represents the flexor/extensor (F/E) ratio. In women, PC1 represents neck strength, PC2 represents anthropometrics, and PC3 represents the F/E ratio. Of the 48 moderation effects tested, only one showed statistical significance after Bonferroni correction, which was not robust to extensive sensitivity analyses. CONCLUSION Neither neck strength nor anthropometrics mitigate adverse associations of soccer heading with cognitive performance in adult amateur players.
Collapse
Affiliation(s)
- Chin Lun Lin
- Montefiore Medical Center, Bronx, New York, United States of America
| | - Bluyé DeMessie
- Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Kenny Ye
- Department of Epidemiology and Population Health, Albert Einstein College of Medicine, Bronx, New York, United States of America
- Department of Systems and Computational Biology, Albert Einstein College of Medicine, Bronx, New York, United States of America
| | - Shanshan Hu
- The Epoch Times, New York, New York, United States of America
| | - Michael L. Lipton
- Department of Radiology, Columbia University Irving Medical Center, New York, New York, United States of America
- Department of Biomedical Engineering, Columbia University, New York, New York, United States of America
| |
Collapse
|
3
|
McLean C, Lavender AP, Pereira E, Peek K, Davey P, Ma’ayah F, Morris S, Georgieva J. The Acute Effects of Ball Pressure on Anticipation Timing Following a Series of Purposeful Headers in Adult Football (Soccer) Players. Sports (Basel) 2024; 12:102. [PMID: 38668570 PMCID: PMC11053744 DOI: 10.3390/sports12040102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 03/21/2024] [Accepted: 03/28/2024] [Indexed: 04/29/2024] Open
Abstract
The purpose of this study is to investigate the acute effects of ball pressure on anticipation timing following a series of purposeful headers in adult football (soccer) players. There is evidence to suggest acute neurophysiological changes to the brain following purposeful heading; this may lead to altered anticipation timing as a result, potentially having future safety implications for players. A repeated measures crossover design was used. Seventeen participants aged between 20 and 30 years performed (i) 20 rotational headers with a lower-pressure match ball (58.6 kPa; 8.5 psi), (ii) 20 rotational headers with a higher-pressure match ball (103.4 kPa; 15 psi), or (iii) 20 non-headers (kicks) as a control each on separate days. The effect of ball pressure on anticipation timing accuracy, measured as absolute, constant, and variable errors, was assessed before and immediately after each intervention session using an anticipation timing task. Differences between group means were compared using repeated measures ANOVA and linear mixed effects models, with p-values of <0.05 considered statistically significant. No significant differences in anticipation timing accuracy across interventions were detected between control, occluded, and non-occluded trials. This finding differs from the previous literature regarding the measurable, acute effects of purposeful heading. The anticipation timing task may lack sensitivity for detecting the effects of repeated heading on brain function.
Collapse
Affiliation(s)
- Chad McLean
- Curtin School of Allied Health, Curtin University, Bentley, WA 6102, Australia (S.M.); (J.G.)
| | - Andrew P. Lavender
- Institute of Health and Wellbeing, Federation University Australia, Ballarat, VIC 3350, Australia
| | - Ethan Pereira
- Curtin School of Allied Health, Curtin University, Bentley, WA 6102, Australia (S.M.); (J.G.)
| | - Kerry Peek
- Discipline of Physiotherapy, Faculty of Health Sciences, University of Sydney, Lidcombe, NSW 2006, Australia;
| | - Paul Davey
- Curtin School of Nursing, Curtin University, Bentley, WA 6102, Australia;
| | - Fadi Ma’ayah
- School of Education, Curtin University, Bentley, WA 6102, Australia;
| | - Susan Morris
- Curtin School of Allied Health, Curtin University, Bentley, WA 6102, Australia (S.M.); (J.G.)
| | - Julia Georgieva
- Curtin School of Allied Health, Curtin University, Bentley, WA 6102, Australia (S.M.); (J.G.)
| |
Collapse
|
4
|
Ferdousi J, Post A, Karton C, Doelle K, Gilchrist MD, Hoshizaki TB. Head trauma analysis of laboratory reconstructed headers using 1966 Slazenger Challenge and 2018 Telstar 18 soccer balls. Sci Rep 2023; 13:18575. [PMID: 37903796 PMCID: PMC10616227 DOI: 10.1038/s41598-023-45489-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Accepted: 10/19/2023] [Indexed: 11/01/2023] Open
Abstract
Retired soccer players are presenting with early onset neurodegenerative diseases, potentially from heading the ball. It has been proposed that the older composition of soccer balls places higher strains on brain tissues. The purpose of this research was to compare the dynamic head response and brain tissue strain of laboratory reconstructed headers using replicas of the 1966 Slazenger Challenge and 2018 Telstar 18 World Cup soccer balls. Head-to-ball impacts were physically conducted in the laboratory by impacting a Hybrid III head form at three locations and four velocities using dry and wet soccer ball conditions, and computational simulation was used to measure the resulting brain tissue strain. This research showed that few significant differences were found in head dynamic response and maximum principal strain between the dry 1966 and 2018 balls during reconstructed soccer headers. Headers using the wet 1966 soccer ball resulted in higher head form responses at low-velocity headers and lower head responses as velocities increased. This study demonstrates that under dry conditions, soccer ball construction does not have a significant effect on head and brain response during headers reconstructed in the laboratory. Although ball construction didn't show a notable effect, this study revealed that heading the ball, comparable to goalkeeper kicks and punts at 22 m/s, led to maximum principal strains exceeding the 50% likelihood of injury risk threshold. This has implications for the potential risks associated with repetitive heading in soccer for current athletes.
Collapse
Affiliation(s)
| | - Andrew Post
- Health Sciences, University of Ottawa, Ottawa, K1N 6N5, Canada
- School of Mechanical and Materials Engineering, University College Dublin, Belfield, Dublin 4, Ireland
| | - Clara Karton
- Health Sciences, University of Ottawa, Ottawa, K1N 6N5, Canada.
| | - Klara Doelle
- Health Sciences, University of Ottawa, Ottawa, K1N 6N5, Canada
| | - Michael D Gilchrist
- School of Mechanical and Materials Engineering, University College Dublin, Belfield, Dublin 4, Ireland
| | | |
Collapse
|
5
|
Filben TM, Tomblin BT, Pritchard NS, Bullock GS, Hemmen JM, Neri KE, Krug V, Miles CM, Stitzel JD, Urban JE. Assessing the association between on-field heading technique and head impact kinematics in a cohort of female youth soccer players. SCI MED FOOTBALL 2023:1-10. [PMID: 37753837 DOI: 10.1080/24733938.2023.2264272] [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] [Received: 04/03/2023] [Accepted: 09/19/2023] [Indexed: 09/28/2023]
Abstract
There is concern that exposure to soccer headers may be associated with neurological sequelae. Training proper heading technique represents a coachable intervention that may reduce head acceleration exposure. The objective was to assess relationships between heading technique and head kinematics in female youth soccer players. Fourteen players (mean age = 14.4 years) wore instrumented mouthpieces during practices and games. Headers were reviewed by three raters to assign a technique score. Mixed models and LASSO regression evaluated associations of technique with peak linear acceleration (PLA), rotational acceleration (PRA), rotational velocity (PRV), and head impact power ratio (HIP Ratio) while adjusting for session type and ball delivery. Two hundred eighty-nine headers (n = 212 standing, n = 77 jumping) were analyzed. Technique score (p = 0.043) and the technique score - session type interaction (p = 0.004) were associated with PRA of standing headers, whereby each 10-unit increase in technique score was associated with an 8.6% decrease in PRA during games but a 5.1% increase in PRA during practices. Technique was not significantly associated with any other kinematic metrics; however, peak kinematics tended to decrease as technique score increased. LASSO regression identified back extension and shoulder/hip alignment as important predictors of peak kinematics. Additional research on heading technique and head acceleration is recommended.
Collapse
Affiliation(s)
- Tanner M Filben
- Department of Biomedical Engineering, Wake Forest University School of Medicine, Winston-Salem, NC, USA
- School of Biomedical Engineering and Sciences, Virginia Tech - Wake Forest University, Winston-Salem, NC, USA
| | - Brian T Tomblin
- Department of Biomedical Engineering, Wake Forest University School of Medicine, Winston-Salem, NC, USA
- School of Biomedical Engineering and Sciences, Virginia Tech - Wake Forest University, Winston-Salem, NC, USA
| | - N Stewart Pritchard
- Department of Biomedical Engineering, Wake Forest University School of Medicine, Winston-Salem, NC, USA
- School of Biomedical Engineering and Sciences, Virginia Tech - Wake Forest University, Winston-Salem, NC, USA
| | - Garrett S Bullock
- Department of Orthopaedic Surgery & Rehabilitation, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - Jordan M Hemmen
- Department of Biomedical Engineering, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - Kristina E Neri
- Department of Biomedical Engineering, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - Victoria Krug
- Department of Biomedical Engineering, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - Christopher M Miles
- Department of Biomedical Engineering, Wake Forest University School of Medicine, Winston-Salem, NC, USA
- Department of Family and Community Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, USA
| | - Joel D Stitzel
- Department of Biomedical Engineering, Wake Forest University School of Medicine, Winston-Salem, NC, USA
- School of Biomedical Engineering and Sciences, Virginia Tech - Wake Forest University, Winston-Salem, NC, USA
| | - Jillian E Urban
- Department of Biomedical Engineering, Wake Forest University School of Medicine, Winston-Salem, NC, USA
- School of Biomedical Engineering and Sciences, Virginia Tech - Wake Forest University, Winston-Salem, NC, USA
| |
Collapse
|
6
|
Pratt RG, Lee G, McAllister AS, Smith DR, Myer GD, Ireland CM, Loew WM, Lanier M, Wang H, Diekfuss JA, Yuan W, Dumoulin CL. A Weighted Head Accelerator Mechanism (WHAM) for visualizing brain rheology using magnetic resonance imaging. J Neurosci Methods 2022; 382:109728. [PMID: 36244524 DOI: 10.1016/j.jneumeth.2022.109728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Revised: 09/16/2022] [Accepted: 10/10/2022] [Indexed: 01/05/2023]
Abstract
BACKGROUND A device for moving the head during MR imaging, called a Weighted Head Accelerator Mechanism (WHAM), rotates the head of a supine subject within programmable rotation limits and acceleration profiles. The WHAM can be used with custom MRI sequences to visualize the deformation and recoil of in vivo brain parenchyma with high temporal resolution, allowing element-wise calculation of strain and shear forces in the brain. Unlike previous devices, the WHAM can be configured to provide a wide range of motion and acceleration profiles. NEW METHOD The WHAM was calibrated using a high-speed camera on a laboratory bench and in 1.5 Tesla and 3.0 Tesla MRI scanners using gel phantoms and human subjects. The MR imaging studies employed a spatial spin-saturation tagging sub-sequence, followed by serial image acquisition. In these studies, 256 images were acquired with a temporal resolution of 2.56 ms. Deformation of the brain was quantified by following the spatial tags in the images. RESULTS MR imaging showed that the WHAM drove quantifiable brain motions using g forces less than those typically observed in day-to-day activities, with peak accelerations of ∼250 rad/sec2. COMPARISON WITH EXISTING METHODS The peak pre-contact accelerations and velocities achieved by the WHAM device in this study are both higher than devices used in previous studies, while also allowing for modification of these factors. CONCLUSIONS MR imaging performed with the WHAM provides a direct method to visualize and quantify "brain slosh" in response to rotational acceleration. Consequently, this approach might find utility in evaluating strategies to protect the brain from mild traumatic brain injury (mTBI).
Collapse
Affiliation(s)
- Ronald G Pratt
- Imaging Research Center, Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | | | - Aaron S McAllister
- Department of Radiology, Nationwide Children's Hospital, Columbus, OH, USA
| | - Daniel R Smith
- Emory Sports Performance And Research Center (SPARC), Flowery Branch, GA, USA; Emory Sports Medicine Center, Atlanta, GA, USA; Department of Orthopaedics, Emory University School of Medicine, Atlanta, GA, USA
| | - Gregory D Myer
- Emory Sports Performance And Research Center (SPARC), Flowery Branch, GA, USA; Emory Sports Medicine Center, Atlanta, GA, USA; Department of Orthopaedics, Emory University School of Medicine, Atlanta, GA, USA; The Micheli Center for Sports Injury Prevention, Waltham, MA, USA.
| | - Christopher M Ireland
- Imaging Research Center, Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA; Department of Biomedical Engineering, University of Cincinnati, Cincinnati, OH, USA
| | - Wolfgang M Loew
- Imaging Research Center, Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA; Department of Radiology, University of Cincinnati, College of Medicine, Cincinnati, OH, USA
| | - Matt Lanier
- Imaging Research Center, Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Hui Wang
- Imaging Research Center, Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA; Philips Healthcare, Cincinnati, OH, USA
| | - Jed A Diekfuss
- Emory Sports Performance And Research Center (SPARC), Flowery Branch, GA, USA; Emory Sports Medicine Center, Atlanta, GA, USA; Department of Orthopaedics, Emory University School of Medicine, Atlanta, GA, USA
| | - Weihong Yuan
- Imaging Research Center, Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA; Department of Radiology, University of Cincinnati, College of Medicine, Cincinnati, OH, USA
| | - Charles L Dumoulin
- Imaging Research Center, Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA; Department of Radiology, University of Cincinnati, College of Medicine, Cincinnati, OH, USA
| |
Collapse
|
7
|
Basinas I, McElvenny DM, Pearce N, Gallo V, Cherrie JW. A Systematic Review of Head Impacts and Acceleration Associated with Soccer. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19095488. [PMID: 35564889 PMCID: PMC9100160 DOI: 10.3390/ijerph19095488] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 04/06/2022] [Accepted: 04/26/2022] [Indexed: 02/04/2023]
Abstract
Epidemiological studies of the neurological health of former professional soccer players are being undertaken to identify whether heading the ball is a risk factor for disease or premature death. A quantitative estimate of exposure to repeated sub-concussive head impacts would provide an opportunity to investigate possible exposure-response relationships. However, it is unclear how to formulate an appropriate exposure metric within the context of epidemiological studies. We have carried out a systematic review of the scientific literature to identify the factors that determine the magnitude of head impact acceleration during experiments and from observations during playing or training for soccer, up to the end of November 2021. Data were extracted from 33 experimental and 27 observational studies from male and female amateur players including both adults and children. There was a high correlation between peak linear and angular accelerations in the observational studies (p < 0.001) although the correlation was lower for the experimental data. We chose to rely on an analysis of maximum or peak linear acceleration for this review. Differences in measurement methodology were identified as important determinants of measured acceleration, and we concluded that only data from accelerometers fixed to the head provided reliable information about the magnitude of head acceleration from soccer-related impacts. Exposures differed between men and women and between children and adults, with women on average experiencing higher acceleration but less frequent impacts. Playing position appears to have some influence on the number of heading impacts but less so on the magnitude of the head acceleration. Head-to-head collisions result in high levels of exposure and thus probably risk causing a concussion. We concluded, in the absence of evidence to the contrary, that estimates of the cumulative number of heading impacts over a playing career should be used as the main exposure metric in epidemiological studies of professional players.
Collapse
Affiliation(s)
- Ioannis Basinas
- Institute of Occupational Medicine, Research Avenue North, Edinburgh EH14 4AP, UK; (I.B.); (D.M.M.)
- Division of Population Health, Health Services Research & Primary Care, Centre for Occupational and Environmental Health, University of Manchester, Oxford Road, Manchester M13 9PL, UK
| | - Damien M. McElvenny
- Institute of Occupational Medicine, Research Avenue North, Edinburgh EH14 4AP, UK; (I.B.); (D.M.M.)
- Division of Population Health, Health Services Research & Primary Care, Centre for Occupational and Environmental Health, University of Manchester, Oxford Road, Manchester M13 9PL, UK
| | - Neil Pearce
- Faculty of Epidemiology and Population Health, London School of Hygiene & Tropical Medicine, London WC1E 7HT, UK;
| | - Valentina Gallo
- Campus Fryslân, University of Groningen, 8911 CE Leeuwarden, The Netherlands;
| | - John W. Cherrie
- Institute of Occupational Medicine, Research Avenue North, Edinburgh EH14 4AP, UK; (I.B.); (D.M.M.)
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Edinburgh EH14 4AS, UK
- Correspondence:
| |
Collapse
|
8
|
Austin K, Lee BJ, Flood TR, Toombs J, Borisova M, Lauder M, Heslegrave A, Zetterberg H, Smith NA. Serum neurofilament light concentration does not increase following exposure to low velocity football heading. SCI MED FOOTBALL 2022; 5:188-194. [PMID: 35077291 DOI: 10.1080/24733938.2020.1853210] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Objectives: To investigate if heading frequency and impact biomechanics in a single session influence the concentration of serum neurofilament light (NF-L), a sensitive biomarker for axonal damage, up to 7 days after heading incident at ball velocities reflecting basic training drills.Methods: Forty-four males were randomized into either control (n = 8), 10 header (n = 12), 20 header (n = 12) or 40 header (n = 12) groups. Linear and angular head accelerations were quantified during heading. Venous blood samples were taken at baseline, 6 h, 24 h and 7 days after heading. Serum NF-L was quantified using Quanterix NF-L assay kit on the Simoa HD-1 Platform.Results: Serum NF-L did not alter over time (p = 0.44) and was not influenced by number of headers [p = 0.47; mean (95% CI) concentrations at baseline 6.00 pg · ml-1 (5.00-7.00 pg · ml-1); 6 h post 6.50 pg · ml-1 (5.70-7.29 pg · ml-1); 24 h post 6.07 pg · ml-1 (5.14-7.01 pg · ml-1); and 7 days post 6.46 pg · ml-1 (5.45-7.46 pg · ml-1)]. There was no relationship between percentage change in NF-L and summed session linear and angular head accelerations.Conclusion: In adult men, heading frequency or impact biomechanics did not affect NF-L response during a single session of headers at ball velocities reflective of basic training tasks.
Collapse
Affiliation(s)
- Kieran Austin
- Institute of Sport, University of Chichester, Chichester, UK
| | - Ben J Lee
- Institute of Sport, University of Chichester, Chichester, UK
| | - Tessa R Flood
- Institute of Sport, University of Chichester, Chichester, UK
| | - Jamie Toombs
- Centre for Discovery Brain Sciences, UK Dementia Research Institute, The University of Edinburgh, UK
| | - Mina Borisova
- Department of Neurodegenerative Diseases, University College London, London, UK.,UK Dementia Research Institute at UCL, London, UK
| | - Mike Lauder
- Institute of Sport, University of Chichester, Chichester, UK
| | - Amanda Heslegrave
- Department of Neurodegenerative Diseases, University College London, London, UK.,UK Dementia Research Institute at UCL, London, UK
| | - Henrik Zetterberg
- Department of Neurodegenerative Diseases, University College London, London, UK.,UK Dementia Research Institute at UCL, London, UK.,Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Neal A Smith
- Institute of Sport, University of Chichester, Chichester, UK
| |
Collapse
|
9
|
Peek K, Andersen J, McKay MJ, Versteegh T, Gilchrist IA, Meyer T, Gardner A. The Effect of the FIFA 11 + with Added Neck Exercises on Maximal Isometric Neck Strength and Peak Head Impact Magnitude During Heading: A Pilot Study. Sports Med 2022; 52:655-668. [PMID: 34590247 PMCID: PMC8480461 DOI: 10.1007/s40279-021-01564-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/05/2021] [Indexed: 12/18/2022]
Abstract
BACKGROUND Higher neck strength has been postulated to reduce head impact magnitude during purposeful heading in football. OBJECTIVES This pilot trial explored the effect of a neck exercise programme on (1) neck strength and (2) head impact magnitude during heading in male and female adolescent football players. METHODS Boys and girls (aged 12-17 years) were randomised by team to the intervention (5 weeks of supervised neuromuscular neck exercises integrated into part 2 of the FIFA 11 + , completed three times per week) or the control group (usual part 2 of the FIFA 11 + , no neck exercises). Outcomes included isometric neck strength and head impact magnitude (peak linear acceleration and peak angular velocity) during standardised heading from a throw-in (at baseline and 6 weeks) plus completion of an evaluation survey by intervention players and coaches. RESULTS In total, 52 players (n = 31 intervention; n = 21 control) completed the study. Mixed-model analysis of variance (ANOVA) revealed significant differences in neck strength variables (p < 0.001), peak linear acceleration (p = 0.04) and peak angular velocity (p = 0.04) between the intervention and control groups over time. Intervention players demonstrated increases in mean composite neck strength (53.8% intervention vs 15.6% control) as well as decreases in mean peak linear head acceleration during heading (- 11.8% vs - 5.0%) from baseline to follow-up. Reduction in peak angular velocity was more pronounced in girls (- 27.7%) than boys (- 11.5%) in the intervention group. The addition of neck exercises into part 2 of the FIFA 11 + was feasible and accepted by players and coaches. CONCLUSION On average, players who completed neck exercises demonstrated an increase in isometric neck strength and a decrease in head impact magnitude during heading. These exercises were easily incorporated into usual training. Australian New Zealand Clinical Trials Registry (no: ACTRN12619001375145).
Collapse
Affiliation(s)
- Kerry Peek
- Discipline of Physiotherapy, School of Health Sciences, Faculty of Medicine and Health, The University of Sydney, Susan Wakil Health Building, Camperdown, Sydney, NSW, Australia.
| | - Jordan Andersen
- School of Health Sciences, Faculty of Medicine and Health, The University of Sydney, Sydney, NSW Australia
| | - Marnee J. McKay
- Discipline of Physiotherapy, School of Health Sciences, Faculty of Medicine and Health, The University of Sydney, Susan Wakil Health Building, Camperdown, Sydney, NSW Australia
| | - Theo Versteegh
- School of Physical Therapy, Western University, London, ON Canada
| | - Ian A. Gilchrist
- School of Kinesiology and Health Studies, Queen’s University, Kingston, ON Canada
| | - Tim Meyer
- Institute of Sports and Preventive Medicine, Medical Faculty, Saarland University, Saarbrücken, Germany
| | - Andrew Gardner
- Priority Research Centre for Stroke and Brain Injury, School of Medicine and Public Health, The University of Newcastle, Newcastle, NSW Australia ,Hunter New England Local Health District Sports Concussion Research Program, Calvary Mater Hospital, Waratah, NSW Australia
| |
Collapse
|
10
|
Müller C, Zentgraf K. Neck and Trunk Strength Training to Mitigate Head Acceleration in Youth Soccer Players. J Strength Cond Res 2021; 35:S81-S89. [PMID: 33065700 DOI: 10.1519/jsc.0000000000003822] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Carsten Müller
- Institute of Sport and Exercise Sciences, University of Münster, Münster, Germany.,University Sports, University of Münster, Münster, Germany; and
| | - Karen Zentgraf
- Department of Movement Science and Training in Sports, Institute of Sport Sciences, Goethe-University Frankfurt, Frankfurt, Germany
| |
Collapse
|
11
|
Koerte IK, Bahr R, Filipcik P, Gooijers J, Leemans A, Lin AP, Tripodis Y, Shenton ME, Sochen N, Swinnen SP, Pasternak O. REPIMPACT - a prospective longitudinal multisite study on the effects of repetitive head impacts in youth soccer. Brain Imaging Behav 2021; 16:492-502. [PMID: 34505977 PMCID: PMC8825640 DOI: 10.1007/s11682-021-00484-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/17/2021] [Indexed: 12/31/2022]
Abstract
Repetitive head impacts (RHI) are common in youth athletes participating in contact sports. RHI differ from concussions; they are considered hits to the head that usually do not result in acute symptoms and are therefore also referred to as “subconcussive” head impacts. RHI occur e.g., when heading the ball or during contact with another player. Evidence suggests that exposure to RHI may have cumulative effects on brain structure and function. However, little is known about brain alterations associated with RHI, or about the risk factors that may lead to clinical or behavioral sequelae. REPIMPACT is a prospective longitudinal study of competitive youth soccer players and non-contact sport controls aged 14 to 16 years. The study aims to characterize consequences of exposure to RHI with regard to behavior (i.e., cognition, and motor function), clinical sequelae (i.e., psychiatric and neurological symptoms), brain structure, function, diffusion and biochemistry, as well as blood- and saliva-derived measures of molecular processes associated with exposure to RHI (e.g., circulating microRNAs, neuroproteins and cytokines). Here we present the structure of the REPIMPACT Consortium which consists of six teams of clinicians and scientists in six countries. We further provide detailed information on the specific aims and the design of the REPIMPACT study. The manuscript also describes the progress made in the study thus far. Finally, we discuss important challenges and approaches taken to overcome these challenges.
Collapse
Affiliation(s)
- Inga K Koerte
- cBRAIN, Department of Child and Adolescent Psychiatry, Psychosomatics, and Psychotherapy, Ludwig-Maximilians-Universität, Munich, Germany. .,Department of Psychiatry, Psychiatry Neuroimaging Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
| | - Roald Bahr
- Oslo Sports Trauma Research Center, Department of Sports Medicine, Norwegian School of Sport Sciences, Oslo, Norway
| | - Peter Filipcik
- Institute of Neuroimmunology, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Jolien Gooijers
- Movement Control and Neuroplasticity Research Group, Department of Movement Sciences, Goup Biomedical Sciences, KU Leuven, Leuven, Belgium.,KU Leuven Brain Institute (LBI), Leuven, Belgium
| | - Alexander Leemans
- PROVIDI Lab, Image Sciences Institute, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Alexander P Lin
- Department of Psychiatry, Psychiatry Neuroimaging Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.,Center for Clinical Spectroscopy, Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Yorghos Tripodis
- Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA.,Boston University Alzheimer's Disease Center and Boston University CTE Center, Boston University School of Medicine, Boston, MA, USA
| | - Martha E Shenton
- Department of Psychiatry, Psychiatry Neuroimaging Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.,Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Nir Sochen
- Department of Applied Mathematics, School of Mathematical Sciences, Tel Aviv University, Tel Aviv, Israel.,Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Stephan P Swinnen
- Movement Control and Neuroplasticity Research Group, Department of Movement Sciences, Goup Biomedical Sciences, KU Leuven, Leuven, Belgium.,KU Leuven Brain Institute (LBI), Leuven, Belgium
| | - Ofer Pasternak
- Department of Psychiatry, Psychiatry Neuroimaging Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.,Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | | |
Collapse
|
12
|
McCunn R, Beaudouin F, Stewart K, Meyer T, MacLean J. Heading in Football: Incidence, Biomechanical Characteristics and the Association with Acute Cognitive Function-A Three-Part Systematic Review. Sports Med 2021; 51:2147-2163. [PMID: 34129222 DOI: 10.1007/s40279-021-01492-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/26/2021] [Indexed: 12/15/2022]
Abstract
BACKGROUND There is growing concern surrounding the role of repetitive sub-concussive head impacts, such as football heading, on brain health. OBJECTIVES Three questions were addressed while only considering studies that observed heading exposure directly: (1) how frequently does heading occur within football training and matches, (2) what are the biomechanical characteristics of heading, and (3) is cognitive function affected by heading? METHODS This review followed the steps described in the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. Electronic databases including MEDLINE and SPORTDiscus were searched from the earliest entry to July 2020. Studies that reported independently quantified heading exposure, biomechanical characteristics of heading or the relationship between heading and cognitive function were included. Data were extracted and used to populate summary tables with reference to each research question. RESULTS Heading incidence ranged between one to nine headers per player per match. The number of headers observed in small-sided games during training varied depending on the exact format used but generally speaking ranged between zero to one per player per game. The three most commonly reported biomechanical variables were head acceleration, head rotational velocity and overall movement kinematics during the heading action. Average head acceleration ranged from approximately four to 50 g. Nine out of 12 included studies did not observe a negative impact on cognitive test performance following exposure to heading and while three did, these negative effects were limited to specific outcome measures: reaction time and memory function. CONCLUSION The current weight of evidence summarised herein does not support the notion that heading is deleterious to cognitive performance in the short term; however, this conclusion is tentative due to methodological shortcomings in the existing evidence base.
Collapse
Affiliation(s)
- Robert McCunn
- Heart of Midlothian Football Club, Tynecastle Park , Edinburgh, EH11 2NL, UK.
| | - Florian Beaudouin
- Institute of Sports and Preventive Medicine, Saarland University, Saarbrücken, Germany
| | - Katy Stewart
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, UK.,Hampden Sports Clinic, Glasgow, UK
| | - Tim Meyer
- Institute of Sports and Preventive Medicine, Saarland University, Saarbrücken, Germany
| | - John MacLean
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, UK.,Hampden Sports Clinic, Glasgow, UK
| |
Collapse
|
13
|
Abstract
Recent public concern over the short- and long-term effects of repetitive head impacts (RHI) associated with purposeful heading in soccer has led researchers to study a multitude of variables related to this important aspect of the game. Of particular interests are the effects of soccer heading in the youth population (≤ 13 years old) whose brains are undergoing rapid development. We conducted a review on youth soccer heading that includes purposeful heading frequency, head impact biomechanics, head injuries, clinical outcomes, and modifying factors. We have concluded that youth soccer players head the ball at a low frequency that typically increases with age and with a finding that boys head the ball more often than girls do. Interestingly, although girls head the ball less frequently than boys do, they tend to sustain higher head impact magnitudes. Head injuries are more likely to occur in girls versus boys and during games because of contact with another player. Clinical outcome measures of concussion are often utilized to study the effects of soccer heading, in both field and laboratory environments. Immediately following soccer heading, youth often report having a headache and demonstrate some deficits in balance measures. Modifying factors that may benefit soccer players participating in purposeful heading activities include stronger neck musculature, wearing headgear, and the use of mouthguards. Research involving youth soccer players needs to be expanded and funded appropriately to better understand the consequences of RHI in both the short and long term.
Collapse
|
14
|
Fílter A, Olivares Jabalera J, Molina-Molina A, Suárez-Arrones L, Robles-Rodríguez J, Dos’Santos T, Loturco I, Requena B, Santalla A. Effect of ball inclusion on jump performance in soccer players: a biomechanical approach. SCI MED FOOTBALL 2021; 6:241-247. [DOI: 10.1080/24733938.2021.1915495] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Alberto Fílter
- FSI Sport Research Lab, Granada, Spain
- Research Group Physical Activity, Health and Sport CTS-948, Pablo De Olavide University, Seville, Spain
| | - Jesús Olivares Jabalera
- FSI Sport Research Lab, Granada, Spain
- Sport and Health University Research Institute (iMUDS), Department of Physical and Sports Education, University of Granada, Granada, Spain
| | - Alejandro Molina-Molina
- Sport and Health University Research Institute (iMUDS), Department of Physical and Sports Education, University of Granada, Granada, Spain
- San Jorge University, Campus Universitario, Villanueva de Gállego, Zaragoza, Spain
| | - Luis Suárez-Arrones
- FSI Sport Research Lab, Granada, Spain
- Research Group Physical Activity, Health and Sport CTS-948, Pablo De Olavide University, Seville, Spain
- San Jorge University, Campus Universitario, Villanueva de Gállego, Zaragoza, Spain
| | | | - Thomas Dos’Santos
- FSI Sport Research Lab, Granada, Spain
- Faculty of Psychology and Sport, University of Huelva, Huelva, Spain
| | - Irineu Loturco
- FSI Sport Research Lab, Granada, Spain
- Department of Exercise and Sport Science, Musculoskeletal Science and sports medicine Research Centre, Manchester Metropolitan University, Manchester, United Kingdom
- NAR – Nucleus of High Performance in Sport, Sao Paulo, Brazil
- University of South Wales, Pontypridd Wales, UK
- Department of Human Movement Sciences, Federal University of São Paulo, Santos, Brazil
| | | | - Alfredo Santalla
- FSI Sport Research Lab, Granada, Spain
- Research Group Physical Activity, Health and Sport CTS-948, Pablo De Olavide University, Seville, Spain
| |
Collapse
|
15
|
Becker S, Berger J, Ludwig O, Günther D, Kelm J, Fröhlich M. Heading in Soccer: Does Kinematics of the Head-Neck-Torso Alignment Influence Head Acceleration? J Hum Kinet 2021; 77:71-80. [PMID: 34168693 PMCID: PMC8008297 DOI: 10.2478/hukin-2021-0012] [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] [Indexed: 11/20/2022] Open
Abstract
There is little scientific evidence regarding the cumulative effect of purposeful heading. The head-neck-torso alignment is considered to be of great importance when it comes to minimizing potential risks when heading. Therefore, this study determined the relationship between head-neck-torso alignment (cervical spine, head, thoracic spine) and the acceleration of the head, the relationship between head acceleration and maximum ball speed after head impact and differences between head accelerations throughout different heading approaches (standing, jumping, running). A total of 60 male soccer players (18.9 ± 4.0 years, 177.6 ± 14.9 cm, 73.1 ± 8.6 kg) participated in the study. Head accelerations were measured by a telemetric Noraxon DTS 3D Sensor, whereas angles for the head-neck-torso alignment and ball speed were analyzed with a Qualisys Track Manager program. No relationship at all was found for the standing, jumping and running approaches. Concerning the relationship between head acceleration and maximum ball speed after head impact only for the standing header a significant result was calculated (p = 0.024, R2 = .085). A significant difference in head acceleration (p < .001) was identified between standing, jumping and running headers. To sum up, the relationship between head acceleration and head-neck-torso alignment is more complex than initially assumed and could not be proven in this study. Furthermore first data were generated to check whether the acceleration of the head is a predictor for the resulting maximum ball speed after head impact, but further investigations have to follow. Lastly, we confirmed the results that the head acceleration differs with the approach.
Collapse
Affiliation(s)
- Stephan Becker
- Department of Sport Science, Technische Universität Kaiserslautern, Kaiserslautern, Germany
| | - Joshua Berger
- Department of Sport Science, Technische Universität Kaiserslautern, Kaiserslautern, Germany
| | - Oliver Ludwig
- Department of Sport Science, Technische Universität Kaiserslautern, Kaiserslautern, Germany
| | - Daniel Günther
- Department of Sport Science, Technische Universität Kaiserslautern, Kaiserslautern, Germany
| | - Jens Kelm
- Chirurgisch-Orthopädisches Zentrum, Illingen, Germany
| | - Michael Fröhlich
- Department of Sport Science, Technische Universität Kaiserslautern, Kaiserslautern, Germany
| |
Collapse
|
16
|
Chen K, Gu H, Zhu L, Feng DF. A New Model of Repetitive Traumatic Brain Injury in Mice. Front Neurosci 2020; 13:1417. [PMID: 32038131 PMCID: PMC6985558 DOI: 10.3389/fnins.2019.01417] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 12/16/2019] [Indexed: 12/14/2022] Open
Abstract
Repetitive traumatic brain injury (rTBI) is a major health care concern that causes substantial neurological impairment. To better understand rTBI, we introduced a new model of rTBI in mice induced by sudden rotation in the coronal plane combined with lateral translation delivered twice at an interval of 24 h. By routine histology, histological examination of Prussian blue-stained sections revealed the presence of microbleed in the corpus callosum and brain stem. Amyloid precursor protein (β-APP) and neurofilament heavy-chain (NF-200) immunohistochemistry demonstrated axonal injury following rTBI. Swelling, waving, and enlargement axons were observed in the corpus callosum and brain stem 24 h after injury by Bielschowsky staining. Ultrastructural studies by electron microscopy provided further insights into the existence and progression of axonal injury. rTBI led to widespread astrogliosis and microgliosis in white matter, as well as significantly increased levels of tumor necrosis factor (TNF)-α and interleukin (IL)-1β. rTBI mice showed a significantly increased loss of righting reflex (LRR) duration within each time point compared with that of sham animals, which was under 15 min. rTBI mice exhibited depression-like behavior at 1 month. rTBI mice also demonstrated deficits in MWM testing. These results suggested that this model might be suitable for investigating rTBI pathophysiology and evaluating preclinical candidate therapeutics.
Collapse
Affiliation(s)
- Kui Chen
- Department of Neurosurgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Institute of Traumatic Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Hao Gu
- Department of Neurosurgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Institute of Traumatic Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Liang Zhu
- Department of Neurosurgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Institute of Traumatic Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Dong-Fu Feng
- Department of Neurosurgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Institute of Traumatic Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| |
Collapse
|
17
|
Becker S, Berger J, Backfisch M, Ludwig O, Kelm J, Fröhlich M. Effects of a 6-Week Strength Training of the Neck Flexors and Extensors on the Head Acceleration during Headers in Soccer. J Sports Sci Med 2019; 18:729-737. [PMID: 31827358 PMCID: PMC6873131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 08/28/2019] [Indexed: 06/10/2023]
Abstract
The importance of well trained and stable neck flexors and extensors as well as trunk muscles for intentional headers in soccer is increasingly discussed. The neck flexors and extensors should ensure a coupling of trunk and head at the time of ball contact to increase the physical mass hitting the ball and reduce head acceleration. The aim of the study was to analyze the influence of a 6-week strength training program (neck flexors, neck extensors) on the acceleration of the head during standing, jumping and running headers as well as after fatigue of the trunk muscles on a pendulum header. A total of 33 active male soccer players (20.3 ± 3.6 years, 1.81 ± 0.07 m, 75.5 ± 8.3 kg) participated and formed two training intervention groups (IG1: independent adult team, IG2: independent youth team) and one control group (CG: players from different teams). The training intervention consisted of three exercises for the neck flexors and extensors. The training effects were verified by means of the isometric maximum voluntary contraction (IMVC) measured by a telemetric Noraxon DTS force sensor. The head acceleration during ball contact was determined using a telemetric Noraxon DTS 3D accelerometer. There was no significant change of the IMVC over time between the groups (F=2.265, p=.121). Head acceleration was not reduced significantly for standing (IG1 0.4 ± 2.0, IG2 0.1 ± 1.4, CG -0.4 ± 1.2; F = 0.796, p = 0.460), jumping (IG1-0.7 ± 1.4, IG2-0.2 ± 0.9, CG 0.1 ± 1.2; F = 1.272, p = 0.295) and running (IG1-1.0 ± 1.9, IG2-0.2 ± 1.4, CG -0.1 ± 1.6; F = 1.050, p = 0.362) headers as well as after fatigue of the trunk musculature for post-jumping (IG1-0.2 ± 2.1, IG2-0.6 ± 1.4; CG -0.6 ± 1.3; F = 0.184, p = 0.833) and post-running (IG1-0.3 ± 1.6, IG2-0.7 ± 1.2, CG 0.0 ± 1.4; F = 0.695, p = 0.507) headers over time between IG1, IG2 and CG. A 6-week strength training of the neck flexors and neck extensors could not show the presumed preventive benefit. Both the effects of a training intervention and the consequences of an effective intervention for the acceleration of the head while heading seem to be more complex than previously assumed and presumably only come into effect in case of strong impacts.
Collapse
Affiliation(s)
- Stephan Becker
- Department of Sport Science, Technische Universität Kaiserslautern, Kaiserslautern, Germany
| | - Joshua Berger
- Department of Sport Science, Technische Universität Kaiserslautern, Kaiserslautern, Germany
| | - Marco Backfisch
- Department of Sport Science, Technische Universität Kaiserslautern, Kaiserslautern, Germany
| | - Oliver Ludwig
- Department of Sport Science, Technische Universität Kaiserslautern, Kaiserslautern, Germany
| | - Jens Kelm
- Medical Faculty, Saarland University, Homburg/Saar, Germany
| | - Michael Fröhlich
- Department of Sport Science, Technische Universität Kaiserslautern, Kaiserslautern, Germany
| |
Collapse
|
18
|
Sandmo SB, McIntosh AS, Andersen TE, Koerte IK, Bahr R. Evaluation of an In-Ear Sensor for Quantifying Head Impacts in Youth Soccer. Am J Sports Med 2019; 47:974-981. [PMID: 30802147 DOI: 10.1177/0363546519826953] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Wearable sensor systems have the potential to quantify head kinematic responses of head impacts in soccer. However, on-field use of sensors (eg, accelerometers) remains challenging, owing to poor coupling to the head and difficulties discriminating low-severity direct head impacts from inertial loading of the head from human movements, such as jumping and landing. PURPOSE To test the validity of an in-ear sensor for quantifying head impacts in youth soccer. STUDY DESIGN Descriptive laboratory study. METHODS First, the sensor was mounted to a Hybrid III headform and impacted with a linear impactor or a soccer ball. Peak linear acceleration (PLA), peak rotational acceleration (PRA), and peak rotational velocity (PRV) were obtained from both systems; random and systematic errors were calculated with Hybrid III as reference. Then, 6 youth soccer players wore sensors and performed a structured training protocol, including heading and nonheading exercises; they also completed 2 regular soccer sessions. For each accelerative event recorded, PLA, PRA, and PRV outputs were compared with video recordings. Receiver operating characteristic curves were used to determine the sensor's discriminatory capacity in both on-field settings, establishing cutoff values for predicting outcomes. RESULTS For the laboratory tests, the random error was 11% for PLA, 20% for PRA, and 5% for PRV; the systematic error was 11%, 19%, and 5%, respectively. For the structured training protocol, heading events resulted in higher absolute values (PLA = 15.6 g± 11.8 g) than nonheading events (PLA = 4.6 g± 1.2 g); the area under the curve was 0.98 for PLA. In regular training sessions, the area under the curve was >0.99 for PLA. A 9 g cutoff value yielded a positive predictive value of 100% in the structured training protocol versus 65% in the regular soccer sessions. CONCLUSION The in-ear sensor displayed considerable random error and substantially overestimated head impact exposure. Despite the sensor's excellent on-field accuracy for discriminating headings from other accelerative events in youth soccer, absolute values must be interpreted with caution, and there is a need for secondary means of verification (eg, video analysis) in real-life settings. CLINICAL RELEVANCE Wearable sensor systems can potentially provide valuable insights into head impact exposures in contact sports, but their limitations require careful consideration.
Collapse
Affiliation(s)
- Stian Bahr Sandmo
- Oslo Sports Trauma Research Center, Department of Sports Medicine, Norwegian School of Sport Sciences, Oslo, Norway.,Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Andrew S McIntosh
- School of Engineering and ACRISP, Edith Cowan University, Joondalup, Australia.,Monash University Accident Research Centre, Monash University, Melbourne, Australia.,McIntosh Consultancy and Research, Sydney, Australia
| | - Thor Einar Andersen
- Oslo Sports Trauma Research Center, Department of Sports Medicine, Norwegian School of Sport Sciences, Oslo, Norway
| | - Inga Katharina Koerte
- Department of Child and Adolescent Psychiatry, Psychosomatic, and Psychotherapy, Ludwig-Maximilian-University, Munich, Germany.,Department of Psychiatry, Psychiatry Neuroimaging Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Roald Bahr
- Oslo Sports Trauma Research Center, Department of Sports Medicine, Norwegian School of Sport Sciences, Oslo, Norway
| |
Collapse
|
19
|
|
20
|
Becker S, Fröhlich M, Kelm J, Ludwig O. The Influence of Fatigued Core Muscles on Head Acceleration during Headers in Soccer. Sports (Basel) 2018; 6:E33. [PMID: 29910337 PMCID: PMC6027546 DOI: 10.3390/sports6020033] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 04/04/2018] [Accepted: 04/09/2018] [Indexed: 11/16/2022] Open
Abstract
The core muscles play a central role in stabilizing the head during headers in soccer. The objective of this study was to examine the influence of a fatigued core musculature on the acceleration of the head during jump headers and run headers. Acceleration of the head was measured in a pre-post-design in 68 soccer players (age: 21.5 ± 3.8 years, height: 180.0 ± 13.9 cm, weight: 76.9 ± 8.1 kg). Data were recorded by means of a telemetric 3D acceleration sensor and with a pendulum header. The treatment encompassed two exercises each for the ventral, lateral, and dorsal muscle chains. The acceleration of the head between pre- and post-test was reduced by 0.3 G (p = 0.011) in jump headers and by 0.2 G (p = 0.067) in run headers. An additional analysis of all pretests showed an increased acceleration in run headers when compared to stand headers (p < 0.001) and jump headers (p < 0.001). No differences were found in the sub-group comparisons: semi-professional vs. recreational players, offensive vs. defensive players. Based on the results, we conclude that the acceleration of the head after fatiguing the core muscles does not increase, which stands in contrast to postulated expectations. More tests with accelerated soccer balls are required for a conclusive statement.
Collapse
Affiliation(s)
- Stephan Becker
- Department of Sport Science, Technische Universität Kaiserslautern, 67663 Kaiserslautern, Germany.
| | - Michael Fröhlich
- Department of Sport Science, Technische Universität Kaiserslautern, 67663 Kaiserslautern, Germany.
| | - Jens Kelm
- Chirurgisch-Orthopädisches Zentrum, 66557 Illingen, Germany.
| | - Oliver Ludwig
- Department of Sport Science, Technische Universität Kaiserslautern, 67663 Kaiserslautern, Germany.
| |
Collapse
|
21
|
Injury mechanism of midfacial fractures in football causes in over 40% typical neurological symptoms of minor brain injuries. Knee Surg Sports Traumatol Arthrosc 2018; 26:1295-1302. [PMID: 28180920 DOI: 10.1007/s00167-017-4431-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 01/13/2017] [Indexed: 10/20/2022]
Abstract
PURPOSE The injury mechanisms of midfacial fractures may be typical causes of concussion, but hardly any scientific data on midfacial injuries sustained in football are available. Head and brain trauma represent frequent injuries in athletes of different sports that require appropriate treatment by sports and trauma physicians. This study investigated the management of midfacial fractures in football and the association of such fractures with concomitant brain injury. METHODS In a prospective cohort study lasting 24 months (2012 to 2013), midfacial injuries of football players were analysed with regard to the injury mechanisms, first aid procedures on the field, treatment and return-to-play. To analyse concomitant and potentially overlooked minor brain injuries due to the trauma, we retrospectively investigated the neurological symptoms of the study population. RESULTS The study included 132 football players (37 semi-professionals and 95 amateurs) with midfacial fractures. The main injury mechanisms were head-to-head and head-to-elbow trauma. The mean period of return-to-play after trauma was 33.5 days, which was significantly shortened if a protective face mask was worn (mean 10.4 days earlier, p = 0.0006). Semi-professional football players returned to play earlier (p = 0.009) and more often used protective face masks (p = 0.001). 55 players (41.6%) had neurological symptoms immediately after trauma as a possible sign of concomitant minor brain injury. 5 of 132 players with concussion had been hospitalised for 24 h, but no persistent neurological symptoms were detected. CONCLUSION In football, midfacial fractures represent moderate-to-severe injuries with time away from sports of more than 4 weeks. Over 40% of athletes with a midfacial fracture showed concomitant neurological symptoms as a sign of minor brain injury. Therefore, sports physicians and other staff supervising athletes in daily practice should be aware of the presence of neurological symptoms. LEVEL OF EVIDENCE Level III.
Collapse
|
22
|
Lamond LC, Caccese JB, Buckley TA, Glutting J, Kaminski TW. Linear Acceleration in Direct Head Contact Across Impact Type, Player Position, and Playing Scenario in Collegiate Women's Soccer Players. J Athl Train 2018; 53:115-121. [PMID: 29373056 DOI: 10.4085/1062-6050-90-17] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
CONTEXT Heading, an integral component of soccer, exposes athletes to a large number of head impacts over a career. The literature has begun to indicate that cumulative exposure may lead to long-term functional and psychological deficits. Quantifying an athlete's exposure over a season is a first step in understanding cumulative exposure. OBJECTIVE To measure the frequency and magnitude of direct head impacts in collegiate women's soccer players across impact type, player position, and game or practice scenario. DESIGN Cross-sectional study. SETTING National Collegiate Athletic Association Division I institution. PATIENTS OR OTHER PARTICIPANTS Twenty-three collegiate women's soccer athletes. MAIN OUTCOME MEASURE(S) Athletes wore Smart Impact Monitor accelerometers during all games and practices. Impacts were classified during visual, on-field monitoring of athletic events. All direct head impacts that exceeded the 10 g threshold were included in the final data analysis. The dependent variable was linear acceleration, and the fixed effects were (1) type of impact: clear, pass, shot, unintentional deflection, or head-to-head contact; (2) field position: goalkeeper, defense, forward, or midfielder; (3) playing scenario: game or practice. RESULTS Shots (32.94 g ± 12.91 g, n = 38; P = .02) and clears (31.09 g ± 13.43 g, n = 101; P = .008) resulted in higher mean linear accelerations than passes (26.11 g ± 15.48 g, n = 451). Head-to-head impacts (51.26 g ± 36.61 g, n = 13; P < .001) and unintentional deflections (37.40 g ± 34.41 g, n = 24; P = .002) resulted in higher mean linear accelerations than purposeful headers (ie, shots, clears, and passes). No differences were seen in linear acceleration across player position or playing scenario. CONCLUSIONS Nonheader impacts, including head-to-head impacts and unintentional deflections, resulted in higher mean linear accelerations than purposeful headers, including shots, clears, and passes, but occurred infrequently on the field. Therefore, these unanticipated impacts may not add substantially to an athlete's cumulative exposure, which is a function of both frequency and magnitude of impact.
Collapse
Affiliation(s)
- Lindsey C Lamond
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark
| | - Jaclyn B Caccese
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark
| | - Thomas A Buckley
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark
| | | | - Thomas W Kaminski
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark
| |
Collapse
|
23
|
Caccese JB, Buckley TA, Tierney RT, Arbogast KB, Rose WC, Glutting JJ, Kaminski TW. Head and neck size and neck strength predict linear and rotational acceleration during purposeful soccer heading. Sports Biomech 2017; 17:462-476. [PMID: 29037111 DOI: 10.1080/14763141.2017.1360385] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
There is increasing societal concern about the long-term effects of repeated impacts from soccer heading, but there is little information about ways to reduce head impact severity. The purpose of this study was to identify factors that contribute to head acceleration during soccer heading. One-hundred soccer players completed 12 controlled soccer headers. Peak linear (PLA) and rotational (PRA) accelerations were measured using a triaxial accelerometer and gyroscope. Head acceleration contributing factors were grouped into 3 categories: size (head mass, neck girth), strength (sternocleidomastoid, upper trapezius) and technique [kinematics (trunk, head-to-trunk range-of-motion), sternocleidomastoid and upper trapezius activity]. Multiple regression analyses indicated size variables explained 22.1% of the variance in PLA and 23.3% of the variance in PRA; strength variables explained 13.3% of the variance in PLA and 17.2% of the variance in PRA; technique variables did not significantly predict PLA or PRA. These findings suggest that head and neck size and neck strength predict PLA and PRA. Anthropometric and neck strength measurements should be considered when determining an athlete's readiness to begin soccer heading.
Collapse
Affiliation(s)
- Jaclyn B Caccese
- a Department of Kinesiology and Applied Physiology , University of Delaware , Newark , DE , USA
| | - Thomas A Buckley
- a Department of Kinesiology and Applied Physiology , University of Delaware , Newark , DE , USA
| | - Ryan T Tierney
- b Department of Kinesiology , Temple University , Philadelphia , PA , USA
| | - Kristy B Arbogast
- c Center for Injury Research and Prevention , Children's Hospital of Philadelphia , Philadelphia , PA , USA
| | - William C Rose
- a Department of Kinesiology and Applied Physiology , University of Delaware , Newark , DE , USA
| | | | - Thomas W Kaminski
- a Department of Kinesiology and Applied Physiology , University of Delaware , Newark , DE , USA
| |
Collapse
|
24
|
Lock JZ, Hegde R, Young S, Lim TC, Amrith S, Sundar G. A study of sports-related orbital fractures in Singapore. Orbit 2017; 36:301-306. [PMID: 28718704 DOI: 10.1080/01676830.2017.1337167] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2016] [Accepted: 05/28/2017] [Indexed: 06/07/2023]
Abstract
With an increased popularity of sport and active living worldwide, our study aims to explore the incidence and features of sports-related orbital fractures in Singapore. 1421 computer tomography (CT) imaging scans of the face and orbits done at the National University Hospital over a 24-month period from January 2013 and December 2014 were reviewed retrospectively for orbital fractures. We identified 483 orbital fractures of which sports injury was the fourth most common etiology (n = 65; 13.5%) after road traffic accident (n = 131; 27.1%), geriatric fall (n = 81; 16.8%) and workplace injury (n = 67; 13.9%). The three most common sport in orbital fractures were soccer (n = 20; 30.8%), bicycling (n = 11; 16.9%) and jogging (n = 8; 12.3%). The three most common fracture patterns were zygomatico-maxillary complex fractures (n = 24; 36.9%), isolated one wall blowout fractures (n = 19; 29.2%) and naso-orbito-ethmoid fractures (n = 7; 10.8%). Sports-related orbital fractures were associated with a low mean age of patients (45.9 years, range, 14-79 years), a higher proportion of males (n = 58; 89.2%) than that from geriatric falls (n = 37, 45.6%) (P < 0.01), a higher likelihood of unilaterality (n = 62; 95.4%) than that from traffic accidents (n = 99; 75.6%) (P < 0.01) and a lower likelihood of pan-facial involvement (n = 4; 6.15%) than that from traffic accident (n = 60; 45.8%) (P < 0.01). Sports-related orbital fractures are the fourth most common cause of orbital fractures. Though commonly seen in young male adults, in view of the aging population and people exercising more regularly, education of safety measures among sports users is paramount to preventing sports-related orbital fractures.
Collapse
Affiliation(s)
- Jing Zhan Lock
- a Yong Loo Lin School of Medicine , National University of Singapore , Singapore
| | - Raghuraj Hegde
- b Department of Ophthalmology , Akshara Eye Hospital , Bangalore , Karnataka , India
| | - Stephanie Young
- c Orbit & Oculofacial Surgery, Department of Ophthalmology , National University Hospital, National University of Singapore , Singapore
| | - Thiam Chye Lim
- d Division of Plastic , Reconstructive and Aesthetic Surgery, National University Hospital , Singapore
| | - Shantha Amrith
- c Orbit & Oculofacial Surgery, Department of Ophthalmology , National University Hospital, National University of Singapore , Singapore
| | - Gangadhara Sundar
- a Yong Loo Lin School of Medicine , National University of Singapore , Singapore
- c Orbit & Oculofacial Surgery, Department of Ophthalmology , National University Hospital, National University of Singapore , Singapore
| |
Collapse
|
25
|
Namjoshi DR, Cheng WH, Bashir A, Wilkinson A, Stukas S, Martens KM, Whyte T, Abebe ZA, McInnes KA, Cripton PA, Wellington CL. Defining the biomechanical and biological threshold of murine mild traumatic brain injury using CHIMERA (Closed Head Impact Model of Engineered Rotational Acceleration). Exp Neurol 2017; 292:80-91. [DOI: 10.1016/j.expneurol.2017.03.003] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2016] [Revised: 02/18/2017] [Accepted: 03/03/2017] [Indexed: 01/05/2023]
|
26
|
Caccese JB. Head accelerations across collegiate, high school and youth female and male soccer players. Br J Sports Med 2017; 52:98-99. [DOI: 10.1136/bjsports-2016-097118] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/08/2017] [Indexed: 11/04/2022]
|
27
|
Becker S, Fröhlich M, Kelm J, Ludwig O. Change of Muscle Activity as Well as Kinematic and Kinetic Parameters during Headers after Core Muscle Fatigue. Sports (Basel) 2017; 5:sports5010010. [PMID: 29910369 PMCID: PMC5969009 DOI: 10.3390/sports5010010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 01/11/2017] [Accepted: 01/18/2017] [Indexed: 11/16/2022] Open
Abstract
In soccer, headers are a tactical measure and influenced by numerous factors. The goal of this study was to identify whether changes in kinematics and muscular activity, especially of the head-stabilizing muscles, occur during headers when the core musculature is fatigued. In two subgroups, muscular activity (12 amateur players, age 23.6 ± 4.2 years) and kinematics and dynamics (29 amateur players, age 23.7 ± 2.8 years) were examined during straight headers on a pendulum header. Data were collected before and after the core muscles were fatigued by an exercise program. Telemetric surface EMG, 3D acceleration sensor, force plate, and video recordings were used. Under fatigue, the activity of M. erector spinae and M. rectus abdominis was significantly reduced in the preparation phase of the header. The activity of M. sternocleidomastoideus was significantly increased during the jump phase, and the hip extension angle during maximum arched body tension was significantly reduced under fatigue. Jumping height, acceleration force impulse, and linear head acceleration were also significantly reduced. We conclude that fatigue of the core muscles affects the motion technique of the header and the activity of the muscle groups stabilizing the head. Therefore, the necessity of specific training in soccer should be emphasized from a medical-preventive point of view.
Collapse
Affiliation(s)
- Stephan Becker
- Department of Sport Science, University of Kaiserslautern, 67663 Kaiserslautern, Germany.
| | - Michael Fröhlich
- Department of Sport Science, University of Kaiserslautern, 67663 Kaiserslautern, Germany.
| | - Jens Kelm
- Chirurgisch-Orthopädisches Zentrum, 66557 Illingen, Germany.
| | - Oliver Ludwig
- Institute of Sports Science, Saarland University, 66123 Saarbruecken, Germany.
| |
Collapse
|
28
|
A Review of Instrumented Equipment to Investigate Head Impacts in Sport. Appl Bionics Biomech 2016; 2016:7049743. [PMID: 27594780 PMCID: PMC4993933 DOI: 10.1155/2016/7049743] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Accepted: 06/23/2016] [Indexed: 11/18/2022] Open
Abstract
Contact, collision, and combat sports have more head impacts as compared to noncontact sports; therefore, such sports are uniquely suited to the investigation of head impact biomechanics. Recent advances in technology have enabled the development of instrumented equipment, which can estimate the head impact kinematics of human subjects in vivo. Literature pertaining to head impact measurement devices was reviewed and usage, in terms of validation and field studies, of such devices was discussed. Over the past decade, instrumented equipment has recorded millions of impacts in the laboratory, on the field, in the ring, and on the ice. Instrumented equipment is not without limitations; however, in vivo head impact data is crucial to investigate head injury mechanisms and further the understanding of concussion.
Collapse
|
29
|
|
30
|
Wu LC, Nangia V, Bui K, Hammoor B, Kurt M, Hernandez F, Kuo C, Camarillo DB. In Vivo Evaluation of Wearable Head Impact Sensors. Ann Biomed Eng 2016; 44:1234-45. [PMID: 26289941 PMCID: PMC4761340 DOI: 10.1007/s10439-015-1423-3] [Citation(s) in RCA: 159] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Accepted: 08/07/2015] [Indexed: 10/23/2022]
Abstract
Inertial sensors are commonly used to measure human head motion. Some sensors have been tested with dummy or cadaver experiments with mixed results, and methods to evaluate sensors in vivo are lacking. Here we present an in vivo method using high speed video to test teeth-mounted (mouthguard), soft tissue-mounted (skin patch), and headgear-mounted (skull cap) sensors during 6-13 g sagittal soccer head impacts. Sensor coupling to the skull was quantified by displacement from an ear-canal reference. Mouthguard displacements were within video measurement error (<1 mm), while the skin patch and skull cap displaced up to 4 and 13 mm from the ear-canal reference, respectively. We used the mouthguard, which had the least displacement from skull, as the reference to assess 6-degree-of-freedom skin patch and skull cap measurements. Linear and rotational acceleration magnitudes were over-predicted by both the skin patch (with 120% NRMS error for a(mag), 290% for α(mag)) and the skull cap (320% NRMS error for a(mag), 500% for α(mag)). Such over-predictions were largely due to out-of-plane motion. To model sensor error, we found that in-plane skin patch linear acceleration in the anterior-posterior direction could be modeled by an underdamped viscoelastic system. In summary, the mouthguard showed tighter skull coupling than the other sensor mounting approaches. Furthermore, the in vivo methods presented are valuable for investigating skull acceleration sensor technologies.
Collapse
Affiliation(s)
- Lyndia C Wu
- Department of Bioengineering, Stanford University, 443 Via Ortega, Stanford, CA, 94305, USA
| | - Vaibhav Nangia
- Department of Mechanical Engineering, Stanford University, Stanford, CA, USA
| | - Kevin Bui
- Department of Bioengineering, Stanford University, 443 Via Ortega, Stanford, CA, 94305, USA
| | - Bradley Hammoor
- Department of Bioengineering, Stanford University, 443 Via Ortega, Stanford, CA, 94305, USA
| | - Mehmet Kurt
- Department of Bioengineering, Stanford University, 443 Via Ortega, Stanford, CA, 94305, USA
| | - Fidel Hernandez
- Department of Mechanical Engineering, Stanford University, Stanford, CA, USA
| | - Calvin Kuo
- Department of Mechanical Engineering, Stanford University, Stanford, CA, USA
| | - David B Camarillo
- Department of Bioengineering, Stanford University, 443 Via Ortega, Stanford, CA, 94305, USA.
- Department of Mechanical Engineering, Stanford University, Stanford, CA, USA.
| |
Collapse
|
31
|
Guley NH, Rogers JT, Del Mar NA, Deng Y, Islam RM, D'Surney L, Ferrell J, Deng B, Hines-Beard J, Bu W, Ren H, Elberger AJ, Marchetta JG, Rex TS, Honig MG, Reiner A. A Novel Closed-Head Model of Mild Traumatic Brain Injury Using Focal Primary Overpressure Blast to the Cranium in Mice. J Neurotrauma 2016; 33:403-22. [PMID: 26414413 PMCID: PMC4761824 DOI: 10.1089/neu.2015.3886] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Mild traumatic brain injury (TBI) from focal head impact is the most common form of TBI in humans. Animal models, however, typically use direct impact to the exposed dura or skull, or blast to the entire head. We present a detailed characterization of a novel overpressure blast system to create focal closed-head mild TBI in mice. A high-pressure air pulse limited to a 7.5 mm diameter area on the left side of the head overlying the forebrain is delivered to anesthetized mice. The mouse eyes and ears are shielded, and its head and body are cushioned to minimize movement. This approach creates mild TBI by a pressure wave that acts on the brain, with minimal accompanying head acceleration-deceleration. A single 20-psi blast yields no functional deficits or brain injury, while a single 25-40 psi blast yields only slight motor deficits and brain damage. By contrast, a single 50-60 psi blast produces significant visual, motor, and neuropsychiatric impairments and axonal damage and microglial activation in major fiber tracts, but no contusive brain injury. This model thus reproduces the widespread axonal injury and functional impairments characteristic of closed-head mild TBI, without the complications of systemic or ocular blast effects or head acceleration that typically occur in other blast or impact models of closed-skull mild TBI. Accordingly, our model provides a simple way to examine the biomechanics, pathophysiology, and functional deficits that result from TBI and can serve as a reliable platform for testing therapies that reduce brain pathology and deficits.
Collapse
Affiliation(s)
- Natalie H. Guley
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, Tennessee
| | - Joshua T. Rogers
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, Tennessee
| | - Nobel A. Del Mar
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, Tennessee
| | - Yunping Deng
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, Tennessee
| | - Rafiqul M. Islam
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, Tennessee
- Department of Anatomy and Histology, Bangladesh Agricultural University, Mymensingh, Bangladesh
| | - Lauren D'Surney
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, Tennessee
- Department of Ophthalmology, The University of Tennessee Health Science Center, Memphis, Tennessee
| | - Jessica Ferrell
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, Tennessee
| | - Bowei Deng
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, Tennessee
| | - Jessica Hines-Beard
- Department of Ophthalmology, The University of Tennessee Health Science Center, Memphis, Tennessee
- Department of Ophthalmology and Visual Sciences, Vanderbilt University, Nashville, Tennessee
| | - Wei Bu
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, Tennessee
| | - Huiling Ren
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, Tennessee
| | - Andrea J. Elberger
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, Tennessee
| | | | - Tonia S. Rex
- Department of Ophthalmology, The University of Tennessee Health Science Center, Memphis, Tennessee
- Department of Ophthalmology and Visual Sciences, Vanderbilt University, Nashville, Tennessee
| | - Marcia G. Honig
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, Tennessee
| | - Anton Reiner
- Department of Anatomy and Neurobiology, The University of Tennessee Health Science Center, Memphis, Tennessee
- Department of Ophthalmology, The University of Tennessee Health Science Center, Memphis, Tennessee
| |
Collapse
|
32
|
Ponce E, Ponce D, Andresen M. Modeling heading in adult soccer players. IEEE COMPUTER GRAPHICS AND APPLICATIONS 2014; 34:8-13. [PMID: 25248195 DOI: 10.1109/mcg.2014.96] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Heading soccer balls can generate mild brain injuries and in the long run can lead to difficulty in solving problems, memory deficits, and language difficulties. Researchers evaluated the effects on the head for both correct and incorrect heading techniques. They based the head's geometry on medical images. They determined the injury's magnitude by comparing the neurological tissue's resistance with predictions of the generated stresses. The evaluation examined fast playing conditions in adult soccer, taking into account the ball's speed and the type of impact. Mathematical simulations using the finite element method indicated that correctly heading balls arriving at moderate speed presents a low risk of brain injury. However, damage can happen around the third cervical vertebra. These results coincide with medical studies. Incorrect heading greatly increases the brain injury risk and can alter the parietal area.
Collapse
|
33
|
van den Eijnde WAJ, Peppelman M, Lamers EAD, van de Kerkhof PCM, van Erp PEJ. Understanding the Acute Skin Injury Mechanism Caused by Player-Surface Contact During Soccer: A Survey and Systematic Review. Orthop J Sports Med 2014; 2:2325967114533482. [PMID: 26535330 PMCID: PMC4555542 DOI: 10.1177/2325967114533482] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Background: Superficial skin injuries are considered minor, and their incidence is probably underestimated. Insight into the incidence and mechanism of acute skin injury can be helpful in developing suitable preventive measures and safer playing surfaces for soccer and other field sports. Purpose: To gain insight into the incidence and severity of skin injuries related to soccer and to describe the skin injury mechanism due to player-surface contact. Study Design: Systematic review; Level of evidence, 4. Methods: The prevention model by van Mechelen et al (1992) combined with the injury causation model of Bahr and Krosshaug (2005) were used as a framework for the survey to describe the skin injury incidence and mechanism caused by player-surface contact. Results: The reviewed literature showed that common injury reporting methods are mainly based on time lost from participation or the need for medical attention. Because skin abrasions seldom lead to absence or medical attention, they are often not reported. When reported, the incidence of abrasion/laceration injuries varies from 0.8 to 6.1 injuries per 1000 player-hours. Wound assessment techniques such as the Skin Damage Area and Severity Index can be a valuable tool to obtain a more accurate estimation of the incidence and severity of acute skin injuries. Conclusion: The use of protective equipment, a skin lubricant, or wet surface conditions has a positive effect on preventing abrasion-type injuries from artificial turf surfaces. The literature also shows that essential biomechanical information of the sliding event is lacking, such as how energy is transferred to the area of contact. From a clinical and histological perspective, there are strong indications that a sliding-induced skin lesion is caused by mechanical rather than thermal injury to the skin.
Collapse
Affiliation(s)
| | - Malou Peppelman
- Department of Dermatology, Radboud University Medical Center, Nijmegen, the Netherlands
| | | | | | - Piet E J van Erp
- Department of Dermatology, Radboud University Medical Center, Nijmegen, the Netherlands
| |
Collapse
|
34
|
Dezman ZDW, Ledet EH, Kerr HA. Neck strength imbalance correlates with increased head acceleration in soccer heading. Sports Health 2014; 5:320-6. [PMID: 24459547 PMCID: PMC3899908 DOI: 10.1177/1941738113480935] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Background: Soccer heading is using the head to directly contact the ball, often to advance the ball down the field or score. It is a skill fundamental to the game, yet it has come under scrutiny. Repeated subclinical effects of heading may compound over time, resulting in neurologic deficits. Greater head accelerations are linked to brain injury. Developing an understanding of how the neck muscles help stabilize and reduce head acceleration during impact may help prevent brain injury. Hypothesis: Neck strength imbalance correlates to increasing head acceleration during impact while heading a soccer ball. Study Design: Observational laboratory investigation. Methods: Sixteen Division I and II collegiate soccer players headed a ball in a controlled indoor laboratory setting while player motions were recorded by a 14-camera Vicon MX motion capture system. Neck flexor and extensor strength of each player was measured using a spring-type clinical dynamometer. Results: Players were served soccer balls by hand at a mean velocity of 4.29 m/s (±0.74 m/s). Players returned the ball to the server using a heading maneuver at a mean velocity of 5.48 m/s (±1.18 m/s). Mean neck strength difference was positively correlated with angular head acceleration (rho = 0.497; P = 0.05), with a trend toward significance for linear head acceleration (rho = 0.485; P = 0.057). Conclusion: This study suggests that symmetrical strength in neck flexors and extensors reduces head acceleration experienced during low-velocity heading in experienced collegiate players. Clinical Relevance: Balanced neck strength may reduce head acceleration cumulative subclinical injury. Since neck strength is a measureable and amenable strength training intervention, this may represent a modifiable intrinsic risk factor for injury.
Collapse
Affiliation(s)
| | - Eric H Ledet
- Rensselaer Polytechnic Institute, Troy, New York
| | | |
Collapse
|
35
|
Schöpfer J, Mai V, Hempel J, Schneider K, Graw M, Adamec J. Forensische Beurteilung des Kopfstoßes. Rechtsmedizin (Berl) 2012. [DOI: 10.1007/s00194-012-0814-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
36
|
|
37
|
Adamec J, Mai V, Graw M, Schneider K, Hempel JM, Schöpfer J. Biomechanics and injury risk of a headbutt. Int J Legal Med 2011; 127:103-10. [DOI: 10.1007/s00414-011-0617-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2011] [Accepted: 08/25/2011] [Indexed: 11/29/2022]
|
38
|
Validation of a wireless head acceleration measurement system for use in soccer play. J Appl Biomech 2011; 26:424-31. [PMID: 21245502 DOI: 10.1123/jab.26.4.424] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Soccer heading has been studied previously with conflicting results. One major issue is the lack of knowledge regarding what actually occurs biomechanically during soccer heading impacts. The purpose of the current study is to validate a wireless head acceleration measurement system, head impact telemetry system (HITS) that can be used to collect head accelerations during soccer play. The HIT system was fitted to a Hybrid III (HIII) head form that was instrumented with a 3-2-2-2 accelerometer setup. Fifteen impact conditions were tested to simulate impacts commonly experienced during soccer play. Linear and angular acceleration were calculated for both systems and compared. Root mean square (RMS) error and cross correlations were also calculated and compared for both systems. Cross correlation values were very strong with r = .95 ± 0.02 for ball to head forehead impacts and r = .96 ± 0.02 for head to head forehead impacts. The systems showed a strong relationship when comparing RMS error, linear head acceleration, angular head acceleration, and the cross correlation values.
Collapse
|
39
|
Soccer-related facial fractures: postoperative management with facial protective shields. J Craniofac Surg 2009; 20:15-20. [PMID: 19164981 DOI: 10.1097/scs.0b013e3181909c55] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Facial fractures are one of the most common orofacial injury sustained during participation in sporting events.The frequency of maxillofacial lesions varies according to the popularity that each sport has in a particular country. Soccer is the most popular sport in Italy, and it is responsible for a large number of facial traumas.Traumas and fractures in soccer mainly involve the zygomatic and nasal regions and are especially caused by direct contact that takes place mainly when the ball is played with the forehead. In particular, elbow-head and head-head impacts are the most frequent dangerous contacts.Soccer is not a violent sport, and the use of protective helmets is not allowed because it could be dangerous especially when players play the ball with the head. The use of protective facial shields are exclusively permitted to preserve players who underwent surgery for facial fractures.The use of a facial protection mask after a facial fracture treatment has already been reported. This article describes a clinical experience of management of 4 soccer-related facial fractures by means of fabrication of individual facial protective shields.
Collapse
|
40
|
Abstract
Sport-related concussion is a common injury in children and adolescents. Athletes seldom report concussive symptoms, which makes the diagnosis a challenge. The management of sport-related concussion has changed significantly over the last several years. The previously used grading systems and return-to-play guidelines have been abandoned in favor of more individualized assessment and management. Neuropsychological testing is being used more frequently to assist in management. After recovery, it is recommended that an athlete's return-to-play progress in a gradual, stepwise fashion while being monitored by a health care provider. Proper assessment and management of a sport-related concussion is crucial, because repeat concussions can result in decreased neurocognitive functioning, increased symptomatology, and, at times, catastrophic outcomes.
Collapse
Affiliation(s)
- William P Meehan
- Children's Hospital Boston, Division of Emergency Medicine, Boston, MA 02115, USA.
| | | |
Collapse
|
41
|
Higgins M, Halstead PD, Snyder-Mackler L, Barlow D. Measurement of impact acceleration: mouthpiece accelerometer versus helmet accelerometer. J Athl Train 2007; 42:5-10. [PMID: 17597937 PMCID: PMC1896070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
CONTEXT Instrumented helmets have been used to estimate impact acceleration imparted to the head during helmet impacts. These instrumented helmets may not accurately measure the actual amount of acceleration experienced by the head due to factors such as helmet-to-head fit. OBJECTIVE To determine if an accelerometer attached to a mouthpiece (MP) provides a more accurate representation of headform center of gravity (HFCOG) acceleration during impact than does an accelerometer attached to a helmet fitted on the headform. DESIGN Single-factor research design in which the independent variable was accelerometer position (HFCOG, helmet, MP) and the dependent variables were g and Severity Index (SI). SETTING Independent impact research laboratory. INTERVENTION(S) The helmeted headform was dropped (n = 168) using a National Operating Committee on Standards for Athletic Equipment (NOCSAE) drop system from the standard heights and impact sites according to NOCSAE test standards. Peak g and SI were measured for each accelerometer position during impact. MAIN OUTCOME MEASURES Upon impact, the peak g and SI were recorded for each accelerometer location. RESULTS Strong relationships were noted for HFCOG and MP measures, and significant differences were seen between HFCOG and helmet g measures and HFCOG and helmet SI measures. No statistically significant differences were noted between HFCOG and MP g and SI measures. Regression analyses showed a significant relationship between HFCOG and MP measures but not between HFCOG and helmet measures. CONCLUSIONS Upon impact, MP acceleration (g) and SI measurements were closely related to and more accurate in measuring HFCOG g and SI than helmet measurements. The MP accelerometer is a valid method for measuring head acceleration.
Collapse
|
42
|
Kirkwood MW, Yeates KO, Wilson PE. Pediatric sport-related concussion: a review of the clinical management of an oft-neglected population. Pediatrics 2006; 117:1359-71. [PMID: 16585334 DOI: 10.1542/peds.2005-0994] [Citation(s) in RCA: 234] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Athletic concussion is a growing focus of attention for pediatricians. Although numerous literature reviews and clinical guidelines are now available pertaining to athletic concussion, few have focused on the pediatric athlete in particular. Sport-related concussions occur relatively frequently in children and adolescents, and primary health care providers are often responsible for coordinating clinical management. Here we summarize the scientific literature pertinent to the care of young athletes. We examine how concussion affects younger and older athletes differently at biomechanical, pathophysiological, neurobehavioral, and contextual levels. We also discuss important issues in clinical management, including preparticipation assessment, concussion evaluation and recovery tracking, and when and how to return pediatric athletes to play sports. We also briefly cover non-sport-related interventions (eg, school support). With proper management, most children and adolescents sustaining a sport-related concussion can be expected to recover fully.
Collapse
Affiliation(s)
- Michael W Kirkwood
- Department of Physical Medicine and Rehabilitation, Children's Hospital, Denver, Colorado, USA.
| | | | | |
Collapse
|
43
|
Tanaka Y. Double-peaked impact force of very soft gel balls. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2006; 73:031403. [PMID: 16605520 DOI: 10.1103/physreve.73.031403] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2005] [Indexed: 05/08/2023]
Abstract
We measure the time change of the contact force F(t) during the impact between very soft gel balls and a rigid substrate. For low-impact velocities Vi, F(t) is single-peak functions as intuitively expected; and the relation between Vi and the peak value Fm [of F(t)] obeys the prediction of the standard theory for the impact in the linear elastic regime (i.e., the Hertz theory). On the other hand, for large Vi, where the gel ball deforms into thin pancakelike shapes, F(t) becomes double-peak functions. We compare the data of F(t) for large Vi with a prediction of a model proposed in our previous study [Tanaka, Europhys. J. E 18, 95 (2005)]. The model can quantitatively reproduce the experimental Fm - Vi relation, and shows that the double-peak behavior of F(t) is a consequence of the expanding deformation of the pancake-shaped gel, i.e., spreading motion parallel to the substrate.
Collapse
Affiliation(s)
- Yoshimi Tanaka
- Creative Research Initiative SOUSEI, Hokkaido University, Kita 21 Nishi 10, Sapporo 011-0021, Japan
| |
Collapse
|
44
|
Withnall C, Shewchenko N, Wonnacott M, Dvorak J. Effectiveness of headgear in football. Br J Sports Med 2005; 39 Suppl 1:i40-8; discussion i48. [PMID: 16046355 PMCID: PMC1765314 DOI: 10.1136/bjsm.2005.019174] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVES Commercial headgear is currently being used by football players of all ages and skill levels to provide protection from heading and direct impact. The clinical and biomechanical effectiveness of the headgear in attenuating these types of impact is not well defined or understood. This study was conducted to determine whether football headgear has an effect on head impact responses. METHODS Controlled laboratory tests were conducted with a human volunteer and surrogate head/neck system. The impact attenuation of three commercial headgears during ball impact speeds of 6-30 m/s and in head to head contact with a closing speed of 2-5 m/s was quantified. The human subject, instrumented to measure linear and angular head accelerations, was exposed to low severity impacts during heading in the unprotected and protected states. High severity heading contact and head to head impacts were studied with a biofidelic surrogate headform instrumented to measure linear and angular head responses. Subject and surrogate responses were compared with published injury assessment functions associated with mild traumatic brain injury (MTBI). RESULTS For ball impacts, none of the headgear provided attenuation over the full range of impact speeds. Head responses with or without headgear were not significantly different (p>0.05) and remained well below levels associated with MTBI. In head to head impact tests the headgear provided an overall 33% reduction in impact response. CONCLUSION The football headgear models tested did not provide benefit during ball impact. This is probably because of the large amount of ball deformation relative to headband thickness. However, the headgear provided measurable benefit during head to head impacts.
Collapse
Affiliation(s)
- C Withnall
- Biokinetics and Associates Ltd, Ontario, Canada.
| | | | | | | |
Collapse
|
45
|
Withnall C, Shewchenko N, Gittens R, Dvorak J. Biomechanical investigation of head impacts in football. Br J Sports Med 2005; 39 Suppl 1:i49-57. [PMID: 16046356 PMCID: PMC1765309 DOI: 10.1136/bjsm.2005.019182] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES This study sought to measure the head accelerations induced from upper extremity to head and head to head impact during the game of football and relate this to the risk of mild traumatic brain injury using the Head Impact Power (HIP) index. Furthermore, measurement of upper neck forces and torques will indicate the potential for serious neck injury. More stringent rules or punitive sanctions may be warranted for intentional impact by the upper extremity or head during game play. METHODS Game video of 62 cases of head impact (38% caused by the upper extremity and 30% by the head of the opposing player) was provided by F-MARC. Video analysis revealed the typical impact configurations and representative impact speeds. Upper extremity impacts of elbow strike and lateral hand strike were re-enacted in the laboratory by five volunteer football players striking an instrumented Hybrid III pedestrian model crash test manikin. Head to head impacts were re-enacted using two instrumented test manikins. RESULTS Elbow to head impacts (1.7-4.6 m/s) and lateral hand strikes (5.2-9.3 m/s) resulted in low risk of concussion (<5%) and severe neck injury (<5%). Head to head impacts (1.5-3.0 m/s) resulted in high concussion risk (up to 67%) but low risk of severe neck injury (<5%). CONCLUSION The laboratory simulations suggest little risk of concussion based on head accelerations and maximum HIP. There is no biomechanical justification for harsher penalties in this regard. However, deliberate use of the head to impact another player's head poses a high risk of concussion, and justifies a harsher position by regulatory bodies. In either case the risk of serious neck injury is very low.
Collapse
Affiliation(s)
- C Withnall
- Biokinetics and Associates Ltd, Ontario, Canada.
| | | | | | | |
Collapse
|
46
|
Shewchenko N, Withnall C, Keown M, Gittens R, Dvorak J. Heading in football. Part 2: biomechanics of ball heading and head response. Br J Sports Med 2005; 39 Suppl 1:i26-32. [PMID: 16046352 PMCID: PMC1765316 DOI: 10.1136/bjsm.2005.019042] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES Controversy surrounding the long term effects of repeated impacts from heading has raised awareness among the public and the medical community. However, there is little information about the human response to the impacts and what measures can be taken to alter their effect. The objective of the current study was to gain a better understanding of heading biomechanics through the implementation of a numerical model and subsequent investigation of parameters related to heading technique and ball characteristics. METHODS A controlled laboratory study was carried out with seven active football players, aged 20-23 years who underwent medical screening and were instrumented with accelerometers mounted in bite plates and electromyographic electrodes on the major neck muscle groups. Balls were delivered at two speeds (6 m/s and 8 m/s) as the subjects demonstrated several specific heading manoeuvres. Photographic targets were tracked via high speed video to measure heading kinematics. One subject demonstrating reasonably averaged flexion-extension muscle activity phased with head acceleration data and upper torso kinematics was used to validate a biofidelic 50th percentile human numerical model with detailed representation of the head and neck. RESULTS Heading kinematics and subject responses were used with a detailed numerical model to simulate impact biomechanics for a baseline heading scenario. Changes to heading techniques and ball characteristics which mitigated head impact response were identified. CONCLUSION A numerical model combined with biomechanical measurement techniques is an important tool for parametric investigation of strategies to reduce head impact severity via changes in heading technique or the physical properties of the ball.
Collapse
Affiliation(s)
- N Shewchenko
- Biokinetics and Associates Ltd, Ontario, Canada.
| | | | | | | | | |
Collapse
|
47
|
Shewchenko N, Withnall C, Keown M, Gittens R, Dvorak J. Heading in football. Part 3: effect of ball properties on head response. Br J Sports Med 2005; 39 Suppl 1:i33-9. [PMID: 16046354 PMCID: PMC1765307 DOI: 10.1136/bjsm.2005.019059] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES Head impacts from footballs are an essential part of the game but have been implicated in mild and acute neuropsychological impairment. Ball characteristics have been noted in literature to affect the impact response of the head; however, the biomechanics are not well understood. The present study determined whether ball mass, pressure, and construction characteristics help reduce head and neck can impact response. METHODS Head responses under ball impact (6-7 m/s) were measured with a biofidelic numerical human model and controlled human subject trials (n = 3). Three ball masses and four ball pressures were investigated for frontal heading. Further, the effect of ball construction in wet/dry conditions was studied with the numerical model. The dynamic ball characteristics were determined experimentally. Head linear and angular accelerations were measured and compared with injury assessment functions comprising peak values and head impact power. Neck responses were assessed with the numerical model. RESULTS Ball mass reductions up to 35% resulted in decreased head responses up to 23-35% for the numerical and subject trials. Similar decreases in neck axial and shear responses were observed. Ball pressure reductions of 50% resulted in head and neck response reductions up to 10-31% for the subject trials and numerical model. Head response reductions up to 15% were observed between different ball constructions. The wet condition generally resulted in greater head and neck responses of up to 20%. CONCLUSION Ball mass, pressure, and construction can reduce the impact severity to the head and neck. It is foreseeable that the benefits can be extended to players of all ages and skill levels.
Collapse
Affiliation(s)
- N Shewchenko
- Biokinetics and Associates Ltd, Ontario, Canada.
| | | | | | | | | |
Collapse
|