Concussions in soccer: a current understanding

The 10-year decreasing trend of youth soccer head injuries and concussions presenting to U.S. emergency departments

OBJECTIVES

Nearly 3 million children participate in youth soccer annually in the United States. Popularity of youth soccer within recent years has prompted investigation describing youth-soccer concussion trends presenting to United States emergency departments (EDs).

METHODS

Data from National Electronic Injury Surveillance System were analyzed for soccer players 2-18 years old sustaining concussions from January 2013 to December 2022. Patient data included age, sex, mechanism of injury, setting (practice vs. game), diagnosis, loss of consciousness, and disposition. Raw data were used to calculate national estimates based on assigned statistical sample weight of each hospital.

RESULTS

A total of 80,582 youth soccer concussions were diagnosed in US EDs (51.0% female, 49.0% male). The most common mechanism of injury was head to ball (31.0%). On average, overall concussions decreased by 572 per year (p = 0.02). Head to body concussions decreased by 169 per year (p < 0.01) and head to ground concussions decreased by 155 per year (p < 0.01). No changes per year in concussion trends for head to ball, head to head, not specified, and other mechanisms. Exclusion of years 2020 and 2021 (COVID), demonstrated decreases in concussions for head to body by 125 (p = 0.01) and head to ground mechanisms by 135 per year (p = 0.01).

CONCLUSION

There is a decreasing trend in youth soccer head injuries and concussions presenting to US emergency departments from 2013 to 2022. The trends from this study indicate that heading may be the most important aspect of soccer-related concussions presenting to US emergency departments. This study contributes to the growing literature regarding concussions in youth soccer athletes.

Mitigating the Risks of Lower Extremity Injuries in Soccer: A Comprehensive Analysis of Lower Extremity Injury Rates in Soccer Between 2014 and 2023

Objective

With events such as the Copa America 2024, the 2026 World Cup, and the arrival of European stars in Major League Soccer (MLS), the already observed and forecasted rise of soccer in the United States (US) seems to be an inevitable outcome. Although regular participation in soccer features several benefits, including increasing cardiovascular health, decreasing stress, and promoting interpersonal relationships, the risk of injury, as is the case in any sport, is ever present. Although many sports that are popular in America feature high rates of concussion, rotator cuff injuries, and general upper extremity injuries, soccer, being more strenuous on the lower-half of the body, features a disproportionate rate of lower extremity injuries. An analysis of the frequencies of these injuries, relative to factors such as year of injury, age, gender, location of injury, and diagnosis of injury, may help organizational bodies and soccer leagues implement new regulations regarding the usage of protective equipment and rules regarding gameplay. This study aims to illuminate these takeaways in an effort to better patient care outcomes in soccer-related injuries.

Method

This paper utilized the National Electronic Injury Surveillance System Database (NEISS) to compile data on lower extremity soccer-related injuries within the defined study period, 2014-2023. Inclusion criteria for the study involved all patients presenting to the emergency department (ED) within the study period and within the defined age range of 0 to 69 years old, with injuries sustained from or related to soccer. Using NEISS, trends were elucidated discriminating based on year of injury, sex, age group, location of injury, and diagnosis group of injury.

Results

Within the defined study period of 10 years, from 2014-2023, there were approximately 843,063 total soccer-related lower extremity injuries which presented to various EDs across the US. Regarding majorities, the most injuries were sustained in 2014 (12.84% of total injuries), most patients sustaining injuries were male (66.6% of all patients), and within the age range of 10-19 years old (63.24% of all patients), with the most instances occurring at age 15. Lower extremity injuries were most reported to be affecting the ankle with 306,797 incidences (36.39% of total injuries seen) and the most frequent diagnosis group was reported to be strains/sprains with 396,420 (47.02% of total injuries seen) total occurrences.

Conclusion

This study analyzes the incidents of lower extremity injuries while participating in soccer for the last 10 years, 2014-2023. The study provides new data regarding the frequency of injuries and their relative rate with respect to year of injury, age group, sex, location of injury, and diagnosis. The results of this study show injury majorities and trends which can be used to dictate changes in regulation regarding gameplay and the utilization of protective equipment in order to mitigate injuries related to the lower extremities in soccer.

Quantitative assessment of brain injury and concussion induced by an unintentional soccer ball impact

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.

Changes in the central nervous system in football players: an MRI study

BACKGROUND

Football (soccer) is the world's most popular team sport.

PURPOSE

To comprehensively examine the brain in football (soccer) players, with the use of magnetic resonance imaging (MRI) techniques.

MATERIAL AND METHODS

The study involved 65 football players and 62 controls. The MR examinations were performed using MR 1.5-T system (Optima MR 360; GE Medical Systems). The examinations were carried out in the 3D Bravo, CUBE, FSEpropeller, and diffusion-weighted imaging (DWI) sequences. The 1HMRS signal was obtained from the volume of interest in the frontal and occipital lobes on both sides.

RESULTS

The present study, based on structural MRI, shows some changes in the brains of the group of football players. The findings show asymmetry of the ventricular system in four football players, arachnoid cysts in the parieto-occipital region, and pineal cysts. NAA/Cr concentration in the right frontal lobe was lower in the football players than in the controls, and the Glx/Cr concentration in the right occipital lobe was higher. The apparent diffusion coefficient value is lower in football players in the occipital lobes.

CONCLUSION

Playing football can cause measurable changes in the brain, known to occur in patients diagnosed with traumatic brain injury. The present findings fill the gap in the literature by contributing evidence showing that playing football may lead to changes in the brain, without clinical symptoms of concussion.

The relationship of cognitive functions with brain damage markers, myokines and neurotrophic factors in amateur soccer players

Concussive and subconcussive head impatcs in sports have drawn more attention in recent years. Thus, the cognitive ability of soccer players and its relationship with circulating levels of irisin, brain-derived neurotrophic factor (BDNF), and neuron-specific enolase (NSE) were studied in this study. Fifteen amateur soccer players and 15 sedentary men volunteered to participate in this study. After evaluating the aerobic and anaerobic capacities of the participants, their cognitive performances were measured. Blood samples were obtained at rest, and the ELISA method was used to measure the concentrations of serum NSE, plasma BDNF, and irisin. There were no differences between groups in terms of cognitive abilities or serum NSE levels (P > 0.05). Plasma irisin (P = 0.019) and BDNF (P < 0.001) levels were higher in the soccer players than the sedentary subjects. There was a positive correlation between irisin and NSE (r = 0.461, P = 0.010) and BDNF (r = 0.405, P = 0.007) concentrations. General cognitive performance is maintained in amateur soccer players. This is accompanied by the unchanged NSE. However, elevated irisin and BDNF levels appear to be independent of cognitive performance.

The Role of Virtual Reality in the Management of Football Injuries

Injuries represent a serious concern for football players, with a significant loss in terms of sport participation and long periods of rehabilitation. According to the 2019/20 UEFA Élite Club Injury Report, the average incidence of injuries during training is 2.8 per 1000 h of training, with an average absence from training of 20 days. In addition, injured athletes are 4 to 7 times more likely to relapse than uninjured athletes. High workloads and reduced recovery periods represent two of the most important modifiable risk factors. In this context, prevention and an adequate rehabilitation protocol are vital in managing injuries, reducing their incidence, and improving the return to competition. In recent years, technological development has provided new tools in rehabilitation, and Virtual reality (VR) has shown interesting results in treating neurologic and orthopedic pathologies. Virtual Reality (VR) technology finds application in the sports industry as a tool to examine athletes' technical movements. The primary objective is to detect the biomechanical risk factors associated with anterior cruciate ligament injury. Additionally, VR can be used to train athletes in field-specific techniques and create safe and controlled therapeutic environments for post-injury recovery. Moreover, VR offers a customizable approach to treatment based on individual player data. It can be employed for both prevention and rehabilitation, tailoring the rehabilitation and training protocols according to the athletes' specific needs.

Assessing Brain Processing Deficits Using Neuropsychological and Vision-Specific Tests for Concussion

INTRODUCTION

Since verbal memory and visual processing transpire within analogous cerebral regions, this study assessed (i) if a visual function can predict verbal memory performance. It also hypothesized whether neurocognitive (e.g., ImPACT) tests focusing on the Visual Memory and Cognitive Efficacy Index will predict Verbal Memory scores and (ii) if vision metrics and age can identify individuals with a history of concussion. Finally, it also hypothesized that King-Devick and near point of convergence scores alongside age considerations will identify candidates with a prior reported history of concussion.

MATERIALS AND METHODS

This observational cohort assessed 25 collegiate ice hockey players prior to the competitive season considering age (19.76 ± 1.42 years) and BMI (25.9 ± 3.0 kg/cm2). Hypothesis 1 was assessed using a hierarchical (sequential) multiple regression analysis, assessing the predictive capacity of Visual Memory and Cognitive Efficacy Index scores in relation to Verbal Memory scores. Hypothesis 2 utilized a binomial logistic regression to determine if King-Devick and near point of convergence scores predict those with a prior history of concussion.

RESULTS

Hypothesis 1 developed two models, where Model 1 included Visual Memory as the predictor, while Model 2 added the Cognitive Efficacy Index as a predictor for verbal memory scores. Model 1 significantly explained 41% of the variance. Results from Model 2 suggest that the Cognitive Efficacy Index explained an additional 24.4%. Thus, Model 2 was interpreted where only the Cognitive Efficacy Index was a significant predictor (p = 0.001). For every 1 unit increase in the Cognitive Efficacy Index, Verbal Memory increased by 41.16. Hypothesis 2's model was significant, accounting for 37.9% of the variance in those with a history of concussion. However, there were no significant unique predictors within the model as age (Wald = 1.26, p = 0.261), King-Devick (Wald = 2.31, p = 0.128), and near point of convergence (Wald = 2.43, p = 0.119) were not significant predictors individually.

CONCLUSIONS

The conflicting findings of this study indicate that baseline data for those with a history of concussion greater than one year may not be comparable to the same metrics during acute concussion episodes. Young athletes who sustain a concussion may be able to overcompensate via the visual system. Future prospective studies with larger sample sizes are required using the proposed model's objective metrics.

It's in the game: A review of neurological lesions associated with sports

INTRODUCTION

The practice of sports may lead to neurological injuries. While relatively uncommon (overall incidence of approximately 2.5%), and mostly benign and transient, some conditions may be life-threatening and permanent. Thus, both clinical neurologists and sports physicians should be aware of their existence and relevance. We aimed to review all sports-related neurological injuries and illnesses reported in the literature.

METHODS

Following SANRA guidelines, we performed a narrative review and searched PubMed and Scopus databases. Relevant sports were selected based on their recognition as an Olympic sport by the International Olympic Committee. Chronic traumatic encephalopathy (CTE) and other neurodegenerative disorders were not included.

RESULTS

A total of 292 studies were included concerning 33 different sports. The most reported neurological injury was damage to the peripheral nervous system. Traumatic injuries have also been extensively reported, including cerebral haemorrhage and arterial dissections. Non-traumatic life-threatening events are infrequent but may also occur, e.g. posterior reversible encephalopathy syndrome, cerebral venous thrombosis, and arterial dissections. Some conditions were predominantly reported in specific sports, e.g. yips in baseball and golf, raising the possibility of a common pathophysiology. Spinal cord infarction due to fibrocartilaginous embolism was reported in several sports associated with minor trauma.

CONCLUSION

Sports-related neurological injuries are increasingly receiving more social and medical attention and are an important cause of morbidity and mortality. This review may serve as a guide to physicians managing these challenging situations.

Trends in Soccer-Related Craniomaxillofacial Injuries, United States 2003-2022

BACKGROUND

Soccer is one of the most popular sports worldwide. However, it has risks of injury to craniomaxillofacial regions such as the head, neck, and mouth.

PURPOSE

The purpose of this study is to determine which demographic and injury characteristics among soccer players with craniomaxillofacial injuries are associated with increased hospitalizations.

STUDY DESIGN, SETTING, AND SAMPLE

This is a retrospective cohort study utilizing the National Electronic Injury Surveillance System. Subjects included in this study experienced an injury to a craniomaxillofacial area from soccer between January 1, 2003, and December 31, 2022.

PREDICTOR VARIABLE

The predictor variables included demographics (age, sex, race) and injury characteristics (craniomaxillofacial region, diagnosis).

MAIN OUTCOME VARIABLE

The primary outcome variable was injury severity defined as hospitalization outcome after injury (yes/no). The secondary outcome variable was the trends in the incidence of soccer craniomaxillofacial injuries over time (2003-2022).

COVARIATES

The covariates were the heterogenous set of predictor variables in this study.

ANALYSES

Descriptive statistics and univariate analyses were computed. Survey-weighted univariate and multivariate logistic regression were used to measure the association of demographic and injury variables with hospitalization outcome. Statistical significance was defined as P < .05.

RESULTS

The study sample included 26,642 subjects (national estimate, 799,393). The national incidence of craniomaxillofacial soccer injuries generally increased between 2003 and 2012 and decreased between 2016 and 2020. Subjects in the ≥30 age group had increased odds of hospitalization compared to those in the 10-19 age group (odds ratio [OR], 2.12; P < .001). Compared to females, males had significantly higher odds of hospitalization (OR, 1.53; P < .001). Head (OR, 8.42; P < .001) and neck (OR, 15.8; P < .001) injuries had increased odds of hospitalization compared to facial injuries. Relative to contusions/abrasions, subjects with fractures (OR, 94.7; P < .001), dental injuries (OR, 41.3; P < .001), and concussions (OR, 5.33; P = .017) were at significantly higher odds of hospitalization.

CONCLUSION AND RELEVANCE

Age, sex, craniomaxillofacial region, and diagnosis were significant predictors of hospitalization outcome after craniomaxillofacial soccer injury. Safer playing styles, use of mouthguards, and proper medical management may reduce future risks of craniomaxillofacial injury from soccer.

Case Report: Indirect Traumatic Optic Neuropathy from Subconcussive Soccer Headers in a 62-year-old Athlete

SIGNIFICANCE

Traumatic optic neuropathy is an uncommon but devastating cause of vision loss after injury to the head. Soccer players may have a heightened risk because of the game's emphasis on heading the ball, a technique in which a player hits the soccer ball with his/her head.

PURPOSE

This article reviews the case of an avid soccer player with traumatic optic neuropathy that occurred after numerous soccer ball headings during a game. This article also (1) provides a summary of the pathophysiology and epidemiology of traumatic optic neuropathy, (2) reviews the current literature on head and eye injuries in soccer, and (3) discusses biomechanical differences in orbital structure throughout aging, which may predispose older patients to traumatic optic neuropathy.

CASE REPORT

We present the case of a 62-year-old male patient who reported to the clinic, after repeated subconcussive soccer ball headers the previous day, with symptoms of blurred vision and "seeing stars" in the right eye and a right inferior visual field impairment. Physical examination, subsequent laboratory work, and neurologic consults implicated traumatic optic neuropathy as the primary diagnosis, and halting soccer playing resulted in symptom improvement.

CONCLUSIONS

Although not commonly encountered in soccer players, the potential for traumatic optic neuropathy exists. Older athletes may be predisposed because of morphological changes of the orbit. Future direction may look to further investigate hazards promoting traumatic optic neuropathy in older athletes and determine possible protections against injury.

Brain Spectroscopy Analysis in Retired Soccer Players With Chronic Exposure to Mild Traumatic Brain Injuries

Soccer players are at risk of suffering cranial injuries in the short and long term. There is growing concern that this may lead to traumatic brain injury in soccer players. Magnetic resonance spectroscopy (MRS) is an analytical method that enables the measurement of changes in brain metabolites that usually occur before significant structural changes. This study aimed to use MRS to compare variations in brain metabolite levels between retired soccer players and a control group. Twenty retired professional soccer players and 22 controls underwent magnetic resonance imaging, including MRS sequences and Mini-Mental State Examination (MMSE). Metabolite analysis was conducted based on absolute concentration and relative ratios. N-acetyl-aspartate, choline, glutamate, glutamine, and myoinositol were the metabolites of interest for the statistical analysis. Retired soccer players had an average age of 57.8 years, whereas the control group had an average age of 63.2 years. Median cognitive evaluation score, assessed using the MMSE, was 28 [26-29] for athletes and 29 [28-30] for controls (p = 0.01). Uni- and multi-variate analyses of the absolute concentration of metabolites (mM) between former athletes and controls did not yield any statistically significant results. Comparison of metabolites to creatine ratio concentrations did not yield any statistically significant results. There were no changes in concentrations of brain metabolites that indicated brain metabolic changes in retired soccer players compared with controls.

Cerebral and cognitive modifications in retired professional soccer players: TC-FOOT protocol, a transverse analytical study

INTRODUCTION

Soccer is the most popular sport in the world. This contact sport carries the risk of exposure to repeated head impacts in the form of subconcussions, defined as minimal brain injuries following head impact, with no symptom of concussion. While it has been suggested that exposure to repetitive subconcussive events can result in long-term neurophysiological modifications, and the later development of chronic traumatic encephalopathy, the consequences of these repeated impacts remain controversial and largely unexplored in the context of soccer players.

METHODS AND ANALYSIS

This is a prospective, single-centre, exposure/non-exposure, transverse study assessing the MRI and neuropsychological abnormalities in professional retired soccer players exposed to subconcussive impacts, compared with high-level athletes not exposed to head impacts. The primary outcome corresponds to the results of MRI by advanced MRI techniques (diffusion tensor, cerebral perfusion, functional MRI, cerebral volumetry and cortical thickness, spectroscopy, susceptibility imaging). Secondary outcomes are the results of the neuropsychological tests: number of errors and time to complete tests. We hypothesise that repeated subconcussive impacts could lead to morphological lesions and impact on soccer players' cognitive skills in the long term.

ETHICS AND DISSEMINATION

Ethics approval has been obtained and the study was approved by the Comité de Protection des Personnes (CPP) No 2021-A01169-32. Study findings will be disseminated by publication in a high-impact international journal. Results will be presented at national and international imaging meetings.

TRIAL REGISTRATION NUMBER

NCT04903015.

Injuries in Recreational Footballers and the Severe Consequences of Player-to-Player Contact: A Prospective Observational Study

Introduction

Football is the most popular sport in the world with its wide audience and important economic effects. This game is mainly played by professional football players, it is also an activity that is frequently played by non-professionals. Although members of the public mostly engage in this sport as a hobby and to develop a healthy lifestyle, vital injuries, such as head and thorax trauma can also occur during these recreational activities. In this study, our aim was to identify these severe traumas, investigate their causes and mechanisms, and make suggestions to reduce trauma among recreational football players.

Methods

This prospectively designed study included players aged over 14 years who presented to the emergency department with an injury incurred during a recreational football match activity. The demographic characteristics of the patients, warm-up status, match conditions, field conditions, and injury mechanisms, as well as post-injury outcomes, were recorded and analyzed with appropriate statistical methods.

Results

There were 167 patients included in the study and 140 of these patients were eligible for the study. We identified 45 cases with poor outcomes such as pneumocephalus, rib fractures, pneumothorax, Achilles tendon rupture, and bone fractures. (32.1%). Factors that could have an effect on poor outcomes were determined as a pre-match warm-up, pre-match sleep duration, and suitability of equipment. Player-to-player contact was determined as a mechanism of head and thorax trauma.

Conclusions

It may be beneficial to inform recreational football players about how player-to-player contact can cause head and thoracic trauma and establish a database of sports injuries in hospitals.

Soccer, concussions, and safety: Perceptions of parents of youth soccer participants

INTRODUCTION

The rate of concussions in youth soccer is among the highest of all youth sports. Parents play an important role in caring for their children and making decisions regarding whether they should participate in a sport, such as soccer, where concussions are well known. This study examined parental perceptions regarding: (a) coaches' role in concussion management, (b) heading restriction policies, and (c) overall concussion risk and participation issues.

METHOD

Online surveys were completed by 419 parents of youth soccer players who participated in the largest U.S. youth soccer programs nationwide.

RESULTS

Findings indicated 44.5% of the respondents had considered keeping their children from playing organized soccer and 47.2% were concerned about a potential decline in youth soccer participation due to concussions. Nearly 69% of responding parents agreed that heading should be banned for participants 10 years old or younger, while 56.5% thought heading should not be limited for participants 13 or older. Only 35% of parents were very confident about their child's coach's ability to properly identify concussions and remove those suspected of a concussion from play. Parents' socioeconomic status (SES), soccer coaching and playing experience, and previous history of concussion(s) were key predictors of greater perceived risk about concussions.

CONCLUSIONS

Findings from this study shed light on parents' perceptions about concussions and related safety issues in youth soccer. Understanding what parents believe about concussions is vital to preserve youth soccer participation and can be used to strengthen education and policies that promote a safer environment for youth sport participants. Practical Applications: Youth soccer coaches can benefit from stronger, comprehensive educational efforts at the league/club level. Additionally, parents of youth athletes who are in the lower SES communities should be targeted to receive concussion safety information and/or interventions that would improve their knowledge, attitude, and practices regarding concussion safety.

The role of pre-season health characteristics as injury risk factors in female adolescent soccer players

[Purpose] Determine if female adolescent soccer players with a history of concussion, impaired K-D scores, and pre-season subjective complaints of neck pain, dizziness, and headache were predisposed to additional risk of musculoskeletal or concussive injury during 10-weeks of competitive play. [Participants and Methods] Twenty-three female high school soccer athletes provided concussion history and reported pre-season subjective complaints. K-D testing was performed pre and postseason. During the 10-week season, all injuries, preventing participation in practice or game, were recorded. [Results] Six reported a history of concussion. Of those six, three injuries were reported, including two concussions and a hamstring strain. Baseline K-D scores were worse in athletes that had two or more pre-season subjective factors compared to those that did not have any. Moderate positive correlations were found between a history of concussion and the number of injuries and a history of concussion and K-D post-test scores. [Conclusion] Findings indicate that pre-season subjective factors of neck pain, dizziness and headache, history of concussion, and K-D potentially increased injury risk. Combining pre-season metrics both at baseline and during the course of the season may assist in better injury risk screening in-season or indicate suboptimal function due to cumulative effects.

Head Impact Situations in Professional Football (Soccer)

To assess head impact incidents (HIIs) and to distinguish diagnosed head injuries from other incidents, a video observation analysis of match HIIs was conducted in the German Bundesliga (2017/18 season). Video recordings of each match were screened to identify the respective events. Head injury data were identified by a prospective injury registry. HII and head injury incidence rates (IR) were calculated with 95% CIs. The total number of HIIs was 1,362 corresponding to an IR of 134.9/1000 match hours (95% CI 127.9–142.2). In 123 HII (IR 12.2, 95% CI 10.2–14.5) the contact was classified as severe. Head contact with the opponent was the most frequent cause (85%). The most frequent mechanism was in 44% (combined) the arm and elbow-to-head, followed by head-to-head and hand-to-head contacts (each 13%). In 58%, the HIIs occurred during header duels. Twenty-nine head injuries were recorded (IR 2.9, 95% CI 2.0–4.1). Concussions/traumatic brain injuries accounted for 48%, head/facial fractures 24%, head/facial contusions 21%, and lacerations/abrasions 7%. The number of HIIs not classified as concussions/more severe trauma was high. Identification of HIIs and head injury severity should be improved during on-field assessment as many head injuries might go unrecognised based on the large number of HIIs.

Youth Soccer Parents' Attitudes and Perceptions About Concussions

PURPOSE

Parents are important figures in properly managing youth sport concussions. Although media attention has predominantly centered on concussions in contact/collision sports, evidence suggests that the concussion rate in soccer is comparable to those found in contact/collision sports. Given the high rate of concussions in youth soccer, this study aimed to examine parents of youth soccer athletes' attitudes and perceptions about concussions and associated factors.

METHODS

A cross-sectional study was conducted by surveying parents of youth soccer athletes from the five largest organized youth soccer programs across the U.S. The researchers developed a questionnaire after an extensive literature review and by modifying previously used instruments.

RESULTS

Overall, 419 parents completed the survey. The vast majority (85%) agreed that a concussion is a serious injury, but only 27.9% believed that their child could suffer a concussion during the next season. Parents were most concerned about permanent brain damage when their child suffers a concussion. The vast majority (4.37 ± .89) perceived concussion reporting as an important injury prevention strategy. Greater appreciation and perceived risk about concussions was found particularly among parents who received concussion education and those who had witnessed or heard about a concussive incidence(s).

CONCLUSIONS

Findings suggest that youth soccer parents have high appreciation and perceived risk about concussions. However, the need for more targeted education was noted, as improvements to better manage and reduce concussions can be made. Future research should continue examining youth sport parents' belief and understanding about concussions as well as factors affecting them.

Video analysis of concussion mechanisms and immediate management in French men's professional football (soccer) from 2015 to 2019

In this study, the concussion mechanisms were analyzed in male professional competition football, with the main objective to specify the frequency of head-to-head impact, and immediate management of the concussed players was described in order to check its compliance with the recommendations of football's governing bodies. Based on continuously recorded data from the French Football Federation (FFF), a retrospective database of all reported concussions during matches in the 1^st and 2^nd French Male leagues was generated comprising seasons 2015/16-2018/19. Injury mechanisms, playing action, immediate medical assessment and management of concussed players, and foul play-referee's decision, were analyzed from video recordings. In total, 41 concussions were reported (incidence rate of 0.44/1000 hours of match exposure [95% CI: 0.40 to 0.49]) of which 36 were identified and analyzed on video sequences. The commonest playing action leading to concussion was aerial challenge (61%), and the main mechanism was head-to-head impact (47%). Following the head impact, 28% of concussed players were not medically assessed on pitch and 53% returned to play the same match. Head-to-head impact was not associated with systematic medical assessment, nor with foul play. In conclusion, the main cause of concussions involved head-to-head impact occurring when two players challenge for heading the ball in the air. The detection of potential concussive head impacts and the immediate management of players possibly concussed during matches remain insufficient according to the international recommendations. Some rules changes, with particular vigilance in case of head-to-head impact, should be discussed.

Changes in resting-state functional brain connectivity associated with head impacts over one men's semi-professional soccer season

Soccer, as a contact sport, exposes players to repetitive head impacts, especially through heading the ball. The question of a long-term brain cumulative effect remains. Our objective was to determine whether exposure to head impacts over one soccer season was associated with changes in functional brain connectivity at rest, using magnetic resonance imaging (MRI). In this prospective cohort study, 10 semi-professional men soccer players, aged 18-25 years, and 20 age-matched men athletes without a concussion history and who do not practice any contact sport were recruited in Bordeaux (France). Exposure to head impacts per soccer player during competitive games over one season was measured using video analysis. Resting-state functional magnetic resonance imaging data were acquired for both groups at two times, before and after the season. With a seed-based analysis, resting-state networks that have been intimately associated with aspects of cognitive functioning were investigated. The results showed a mean head impacts of 42 (±33) per soccer player over the season, mainly intentional head-to-ball impacts and no concussion. No head impact was found among the other athletes. The number of head impacts between the two MRI acquisitions before and after the season was associated with increased connectivity within the default mode network and the cortico-cerebellar network. In conclusion, our findings suggest that the brain functioning changes over one soccer season in association with exposure to repetitive head impacts.

Heading in the Right Direction: A Critical Review of Studies Examining the Effects of Heading in Soccer Players

The practice of heading in soccer has become a public concern because of the potential for subconcussive impacts to cause cumulative concussive-like effects; however, experimental evidence for this hypothesis has been mixed. This systematic review used pre-defined search parameters to assess primary literature that examined changes in cognitive, behavioral, structural, and/or biological processes after acute heading exposure in youth and young adult soccer players. The findings were synthesized into a concise and comprehensive summary of the research following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) format, and suggestions for standardization of acute heading protocols are described. A total of 1189 articles were considered for this review, with 19 articles meeting all of the inclusion criteria for full analysis. An attempt was made to identify methods with significant sensitivity and reliability by grouping studies based on their outcome measures. Because of lack of standardization across intervention types and data collection protocols, no sensitive and reliable methods could be identified conclusively to assess the effects of acute heading exposure in soccer players. Based on this review, there is not enough evidence to either support or refute the potential of effects of subconcussive events from acute soccer heading exposure. Recommendations for standardization of acute heading exposure studies based on the included literature are discussed. Standardization is required to better understand the impact of acute heading exposure in soccer players, while allowing for the development of guidelines that mitigate any potential risks and allowing athletes to remain active and develop their skills.

Head impacts in semiprofessional male Soccer players: a prospective video analysis over one season of competitive games

Soccer exposes players to head injuries and involves repeated intentional head impacts through heading the ball. Our objective was to investigate the rate of both intentional headers and involuntary head impacts in semiprofessional male soccer players during one season. In this prospective cohort study, we followed 54 men (16-35 years) playing in two soccer clubs participating in the same regional French championship throughout the 2017-2018 season. All head impacts that occurred in competitive games were analyzed using video recordings. Player position, game exposure, referee's decision were also reported. Head impact incidence rate (IR) per 1000 player-hours, with the 95% confidence intervals (CIs) were calculated. Results: Headers IR was 3584.7 per 1000 player-hours (95% CI = 3431.9, 3737.5). Forwards and center-backs performed a higher number of headers. Involuntary head impacts IR was 44.1/1000 player-hours (95% CI = 27.1, 60.9). Just under half led the referee to stop playing time for a caregiver examination. Three concussions with a loss of consciousness after a head-to-head impact in a heading duel were recorded. Conclusions: Intentional headers were relatively common, contrary to involuntary head impacts that were however mainly due to heading duels. Head-to-head impact should lead to a systematic exit from the game for suspicion of concussion.

Factors affecting peak impact force during soccer headers and implications for the mitigation of head injuries

It has been documented that up to 22% of all soccer injuries are concussions. This is in part due to players purposely using their head to direct the ball during play. To provide a more complete understanding of head trauma in soccer athletes, this study characterized the effects of four soccer ball characteristics (size, inflation pressure, mass, velocity) on the resulting peak impact force as it relates to the potential for incurring neurophysiological changes. A total of six hundred trials were performed on size 4 and 5 soccer balls as well as a novel lightweight soccer ball. Impact force was measured with a force plate and ball velocity was determined using motion capture. These data were used, in conjunction with dimensional analysis to relate impact force to ball size, mass, velocity, and pressure. Reasonable reductions in allowable ball parameters resulted in a 19.7% decrease in peak impact force. Adjustments to ball parameters could reduce a high cumulative peak translational acceleration soccer athlete down into a previously defined safer low loading range. In addition, it was noted that water absorption by soccer balls can result in masses that substantially increase impact force and quickly surpass the NCAA weight limit for game play. Additional research is required to determine whether varying soccer ball characteristics will enable soccer players to avoid persistent neurophysiological deficits or what additional interventions may be necessary and the legal implications of these data are discussed.

Soccer-related head injuries-analysis of sentinel surveillance data collected by the electronic Canadian Hospitals Injury Reporting and Prevention Program

Background

Participating in sports is a great way to gain physical, psychological, and social benefits. However, it also carries the risk of injury. Soccer is one of the most popular sports worldwide, and in recent years, there have been concerns about potential vulnerabilities to head injuries.

Objectives

To investigate soccer-related head injuries (SRHIs), using data from the electronic Canadian Hospitals Injury Reporting and Prevention Program (eCHIRPP) surveillance system. Specifically, we aim to compare characteristics of SRHI cases to all head injury cases within the eCHIRPP database.

Methods

Descriptive analyses of emergency department (ED) injury surveillance data (2011 to 2017) for individuals aged 5 to 29 years from all participating eCHIRPP sites. Computation of proportionate injury ratios (PIR) comparing SRHIs to all head injuries reported to eCHIRPP, and 95% confidence intervals (CI).

Results

A total of 3,970 SRHIs were reported to eCHIRPP. Injuries were from contact with another player, the ball, ground, goal-post, and other causes. Of the injuries caused by contact with the ball, 9% were from purposely directing the ball with the head (heading). A higher proportion of concussions (PIR=1.32, 95% confidence interval [CI]: 1.27 to 1.37) and minor closed head injuries (PIR=1.20, 95% CI: 1.15 to 1.26) were observed in soccer players. Higher proportions of head injuries occurred in organized soccer and soccer played outdoors. However, admission to the ED for a SRHI was rare (PIR=0.40, 95% CI: 0.30 to 0.55).

Conclusions

Overall, elevated proportions of brain injuries were observed among soccer players, however, these injuries were unlikely to result in a hospital admission. Moreover, purposely heading the ball contributed to few ED visits.

Reducing risk of head injury in youth soccer: An extension of behavioral skills training for heading

Recently, concerns regarding sport-related concussions have increased within the research literature, the media, and popular culture. One potential source of soccer-related concussions involves the purposeful striking of the ball with one's head (i.e., heading). There is currently limited research on an effective teaching method to improve safe heading technique. In the current study, Behavior Skills Training (BST) was evaluated as a method to teach correct heading techniques to youth soccer players. BST increased the percentage of correct steps for each player based on a task analysis of heading. Based on social validity questionnaires administered to players and the coach, BST was rated as an acceptable form of training. After the final training session, experienced coaches rated each player as having improved from baseline to training.

Management of concussion in soccer

BACKGROUND

When participating in contact sports, (mild) head trauma is a common incident-observed in both professional and amateur sports. When head trauma results in transient neurological impairment, a sports-related concussion has occurred. Acute concussion, repetitive concussions, as well as cumulative "sub-concussive" head impacts may increase the risk of developing cognitive and behavioral deficits for athletes, as well as accelerated cerebral degeneration. While this concept has been well established for classic contact sports like American Football, Rugby, or Boxing, there is still an awareness gap for the role of sports-related concussion in the context of the world's most popular sport-Soccer.

METHODS

Here, we review the relevance of sport-related concussion for Soccer as well as its diagnosis and management. Finally, we provide insight into future directions for research in this field.

RESULTS

Soccer fulfills the criteria of a contact sport and is characterized by a high incidence of concussion. There is ample evidence that these events cause functional and structural cerebral disorders. Furthermore, heading, as a repeat sub-concussive impact, has been linked to structural brain changes and neurocognitive impairment. As a consequence, recommendations for the diagnosis and management of concussion in soccer have been formulated by consensus groups. In order to minimize the risk of repetitive concussion in soccer the rapid and reliable side-line diagnosis of concussion with adoption of a strict remove-from-play protocol is essential, followed by a supervised, graduated return-to-play protocol. Recent studies, however, demonstrate that adherence to these recommendations by players, coaches, clubs, and officials is insufficient, calling for stricter enforcement. In addition, future research to solidify the pathophysiological relevance of concussion for soccer athletes seems to be needed. Advanced neuroimaging and neurochemical biomarker analyses (e.g. S100β, tau and neurofilament light (NfL)) may assist in detecting concussion-related structural brain changes and selecting athletes at risk for irreversible damage.

CONCLUSION

Sports-related concussion represents a genuine neurosurgical field of interest. Given the high socioeconomic relevance, neurosurgeons should get involved in prevention and management of concussion in soccer.

Time Trends of Head Injuries Over Multiple Seasons in Professional Male Football (Soccer)

The present study aimed to investigate time trends of head injuries and their injury mechanisms since a rule change as monitoring may help to identify causes of head injuries and may advance head injury prevention efforts. Based on continuously recorded data from the German football magazine “kicker Sportmagazin ^® ” as well as other media sources, a database of head injuries in the 1 ^st German male Bundesliga was generated comprising 11 seasons (2006/07–2016/17). Injury mechanisms were analysed from video recordings. Injury incidence rates (IR) and 95% confidence intervals (95% CI) were calculated. Time trends were analysed via linear regression. Two hundred thirty-eight match head injuries occurred (IR 1.77/1000 match hours, 95% CI 1.56–2.01). There were no significant seasonal changes, expressed as annual average year-on-year change, in IRs over the 11-year period for total head injuries (p=0.693), facial/head fractures (p=0.455), lacerations/abrasions (p=0.162), and head contusions (p=0.106). The annual average year-on-year increase for concussion was 6.4% (p=0.004). Five head injury mechanisms were identified. There were no seasonal changes in injury mechanisms over the study period. The concussion subcategory increased slightly over the seasons, which may either be a result of increasing match dynamics or raised awareness among team physicians and players.

American football and other sports injuries may cause migraine/persistent pain decades later and can be treated successfully with electrical twitch-obtaining intramuscular stimulation (ETOIMS)

Introduction

Autonomous twitch elicitation at myofascial trigger points from spondylotic radiculopathies-induced denervation supersensitivity can provide favourable pain relief using electrical twitch-obtaining intramuscular stimulation (ETOIMS).

Aim

To provide objective evidence that ETOIMS is safe and efficacious in migraine and persistent pain management due to decades-old injuries to head and spine from paediatric American football.

Methods and materials

An 83-year-old mildly hypertensive patient with 25-year history of refractory migraine and persistent pain self-selected to regularly receive fee-for-service ETOIMS 2/week over 20 months. He had 180 sessions of ETOIMS. Pain levels, blood pressure (BP) and heart rate/pulse were recorded before and immediately after each treatment alongside highest level of clinically elicitable twitch forces/session, session duration and intervals between treatments. Twitch force grades recorded were from 1 to 5, grade 5 twitch force being strongest.

Results

Initially, there was hypersensitivity to electrical stimulation with low stimulus parameters (500 µs pulse-width, 30 mA stimulus intensity, frequency 1.3 Hz). This resolved with gradual stimulus increments as tolerated during successive treatments. By treatment 27, autonomous twitches were noted. Spearman's correlation coefficients showed that pain levels are negatively related to twitch force, number of treatments, treatment session duration and directly related to BP and heart rate/pulse. Treatment numbers and session durations directly influence twitch force. At end of study, headaches and quality of life improved, hypertension resolved and antihypertensive medication had been discontinued.

Conclusions

Using statistical process control methodology in an individual patient, we showed long-term safety and effectiveness of ETOIMS in simultaneous diagnosis, treatment, prognosis and prevention of migraine and persistent pain in real time obviating necessity for randomised controlled studies.

Head injuries in children's football-results from two prospective cohort studies in four European countries

Head injuries are considered harmful in children. We analyzed head and neck injuries in organized football in 7- to 12-year-old children. Data for this analysis were obtained from a prospective cohort study over two consecutive football seasons in two European countries, and a randomized intervention trial over one season in four European countries. Football exposure and injuries were documented through an online database. Detailed information regarding injury characteristics and medical follow-up was retrieved from coaches, children and parents by phone. Thirty-nine head injuries and one neck injury (5% of all 791 injuries) were documented during 9933 player-seasons (total football exposure 688 045 hours). The incidence was 0.25 [95%CI 0.15, 0.35] head/neck injuries per 1000 match hours (N=23 match injuries) and 0.03 [95%CI 0.02, 0.03] per 1000 training hours. Eleven concussions (27.5%), nine head contusions (22.5%), eight lacerations or abrasions (20%), two nose fractures (2.5%), and two dental injuries (2.5%) occurred. The remaining eight injuries were nose bleeding or other minor injuries. Thirty injuries (75%) resulted from contact with another player, and ten injuries were due to collision with an object, falling or a hit by the ball. Whereas 70% of all head injuries (N=28) were due to frontal impacts, 73% of concussions (N=8) resulted from an impact to the occiput. The incidence and severity of head injuries in children's football are low. Coaches and parents, however, should be sensitized regarding the potential of concussions, particularly after an impact to the occiput.

English professional football players concussion knowledge and attitude

BACKGROUND

Concussions are a common pathology in football and multiple misconceptions exist amongst the players and managers. To address these misconceptions, and potentially reduce concussion associated sequela, effective educational interventions need to be developed. However, the current knowledge and attitude status must be ascertained to appropriately develop these interventions. The purpose of this study was to assess the concussion knowledge and attitude of English professional footballers.

METHODS

Twenty-six participants from one English Football League Championship club completed the study. A mixed methods approach included the Rosenbaum Concussion Knowledge and Attitudes Survey (RoCKAS) and a semi-structured interview. The RoCKAS contains separate knowledge (0-25) and attitude (15-75) scores and was followed by a semi-structured interview consisting of concussion knowledge, attitude, and behavior related questions.

RESULTS

The mean score on the RoCKAS knowledge was 16.4 ± 2.9 (range 11-22) and the attitude score was 59.6 ± 8.5 (range 41-71). The interview responses identified inconsistencies between the RoCKAS and the intended behaviors, endorsing multiple concussion misconceptions, and revealed barriers to concussion reporting.

CONCLUSION

The results of this study suggest that Championship Level English footballers have moderate concussion knowledge, safe attitudes, and good concussion symptom recognition when assessed with pen and paper questionnaires. However, within the semi-structured interview many respondents reported unsafe concussion behaviors despite accurately identifying the potential risks. Further, multiple barriers to concussion reporting were identified which included perceived severity of the injury, game situations, and the substitution rule. These findings can help form the foundation of educational interventions to potentially improve concussion reporting behaviors amongst professional footballers.

Effects of Soccer Heading on Brain Structure and Function

Soccer is the most popular sport in the world, with more than 265 million players worldwide, including professional and amateur ones. Soccer is unique in comparison to other sports, as it is the only sport in which participants purposely use their head to hit the ball. Heading is considered as an offensive or defensive move whereby the player's unprotected head is used to deliberately impact the ball and direct it during play. A soccer player can be subjected to an average of 6-12 incidents of heading the ball per competitive game, where the ball reaches high velocities. Moreover, in practice sessions, heading training, which involves heading the ball repeatedly at low velocities, is common. Although the scientific community, as well as the media, has focused on the effects of concussions in contact sports, the role of subconcussive impacts, as it can occur during heading, has recently gained attention, considering that it may represent an additional mechanism of cumulative brain injury. The purpose of this study is to review the existing literature regarding the effects of soccer heading on brain structure and function. Only in the last years, some investigations have addressed the impact of heading on brain structure, by using neuroimaging techniques. Similarly, there have been some recent studies investigating biochemical markers of brain injury in soccer players. There is evidence of association between heading and abnormal brain structure, but the data are still preliminary. Also, some studies have suggested that subconcussive head impacts, as heading, could cause cognitive impairment, whereas others have not corroborated this finding. Questions persist as to whether or not heading is deleterious to cognitive functioning. Further studies, especially with longitudinal designs, are needed to clarify the clinical significance of heading as a cause of brain injury and to identify risk factors. Such investigations might contribute to the establishment of safety guidelines that could help to minimize the risk of possible adverse effects of soccer on brain structure and function.

Head injury predictors in sports trauma--a state-of-the-art review

Head injuries occur in a great variety of sports. Many of these have been associated with neurological injuries, affecting the central nervous system. Some examples are motorsports, cycling, skiing, horse riding, mountaineering and most contact sports such as football, ice and field hockey, soccer, lacrosse, etc. The outcome of head impacts in these sports can be very severe. The worst-case scenarios of permanent disability or even death are possibilities. Over recent decades, many In recent decades, a great number of head injury criteria and respective thresholds have been proposed. However, the available information is much dispersed and a consensus has still not been achieved regarding the best injury criteria or even their thresholds. This review paper gives a thorough overview of the work carried out by the scientific community in the field of impact biomechanics about head injuries sustained during sports activity. The main goal is to review the head injury criteria, as well as their thresholds. Several are reviewed, from the predictors based on kinematics to the ones based on human tissue thresholds. In this work, we start to briefly introduce the head injuries and their mechanisms commonly seen as a result of head trauma in sports. Then, we present and summarize the head injury criteria and their respective thresholds.

Networks of neuroinjury semantic predications to identify biomarkers for mild traumatic brain injury

Objective

Mild traumatic brain injury (mTBI) has high prevalence in the military, among athletes, and in the general population worldwide (largely due to falls). Consequences can include a range of neuropsychological disorders. Unfortunately, such neural injury often goes undiagnosed due to the difficulty in identifying symptoms, so the discovery of an effective biomarker would greatly assist diagnosis; however, no single biomarker has been identified. We identify several body substances as potential components of a panel of biomarkers to support the diagnosis of mild traumatic brain injury.

Methods

Our approach to diagnostic biomarker discovery combines ideas and techniques from systems medicine, natural language processing, and graph theory. We create a molecular interaction network that represents neural injury and is composed of relationships automatically extracted from the literature. We retrieve citations related to neurological injury and extract relationships (semantic predications) that contain potential biomarkers. After linking all relationships together to create a network representing neural injury, we filter the network by relationship frequency and concept connectivity to reduce the set to a manageable size of higher interest substances.

Results

99,437 relevant citations yielded 26,441 unique relations. 18,085 of these contained a potential biomarker as subject or object with a total of 6246 unique concepts. After filtering by graph metrics, the set was reduced to 1021 relationships with 49 unique concepts, including 17 potential biomarkers.

Conclusion

We created a network of relationships containing substances derived from 99,437 citations and filtered using graph metrics to provide a set of 17 potential biomarkers. We discuss the interaction of several of these (glutamate, glucose, and lactate) as the basis for more effective diagnosis than is currently possible. This method provides an opportunity to focus the effort of wet bench research on those substances with the highest potential as biomarkers for mTBI.

High occurrence of head and spine injuries in the pediatric population following motocross accidents

OBJECT

Off-road motorcycling is a very popular sport practiced by countless people worldwide. Despite its popularity, not much has been published on the severity and distribution of central nervous system-related injuries associated with this activity in the pediatric population. The purpose of this study was to confirm, characterize, and document the rate of head and spine injuries associated with off-road motorcycling in this population.

METHODS

All patients aged 18 years or less who were treated for a motorbike injury at the authors' institution (a Level 1 regional trauma center) between 2000 and 2007 were identified through in-house surgical and trauma registries. Type, mechanism, and severity of CNS-related injuries were assessed, including: incidence of traumatic brain injury (TBI), loss of consciousness (LOC), Glasgow Coma Scale (GCS) score, head CT findings, neurological deficits, spinal fractures, cervical strain, and use of protective gear, including helmets.

RESULTS

During the 8-year period of study, 298 accidents were evaluated in 248 patients. The patients' mean age at the time of injury was 14.2 ± 2.7 years. Head injury or TBI was identified in 60 (20.1%) of 298 cases (involving 58 of 248 patients). Fifty-seven cases were associated with LOC, and abnormalities were identified on head CT in 10 patients; these abnormalities included skull fractures and epidural, subdural, subarachnoid, and intraparenchymal hemorrhages. The GCS score was abnormal in 11 cases and ranged from 3 to 15, with an overall mean of 14.5. No patients required cranial surgery. Helmet use was confirmed in 43 (71.6%) of the cases involving TBI. Spine fractures were identified in 13 patients (4.3%) and 5 required surgical fixation for their injury.

CONCLUSIONS

The authors found a high occurrence of head injuries following pediatric off-road motorcycle riding or motocross accidents despite the use of helmets. Additionally, this study severely underestimates the rate of mild TBIs in this patient population. Our data indicate that motocross is a high-risk sport despite the use of protective gear. Riders and parents should be counseled accordingly about the risks prior to participation.

Return to play management after concussion in football: recommendations for team physicians

A concussion is a rare but potentially serious injury of football players. Thus, an immediate and valid diagnosis, estimate of severity and therapeutic management is required. To summarise the published information on management of concussion with respect to a safe return to play (RTP), a literature search was conducted. Current guidelines on concussion in sports and significant studies on concussion in football were analysed. After concussion, management and RTP decision should remain in the area of clinical judgement on an individualised basis according to the current international guidelines. If a concussion is suspected, the player should not be allowed to RTP the same day. The RTP programme should follow a gradual step-wise procedure. A concussed player should not RTP unless he/she is asymptomatic and the neurological and neuropsychological examinations are normal. Untimely RTP bears an increased risk of sustaining another more severe brain injury and repetitive brain injury of long-term sequelae. In football, the management of concussion should primarily follow the recommendations proposed by the Concussion in Sports Group. Information and education of players and their medical and coaching team help to protect the players' health. Future studies on concussion should include validated and detailed information on RTP protocols.