During the 2009 to 2010 academic year, 192 US high schools reported data for athletes participating in 20 sports (boys: baseball, basketball, football, ice hockey, lacrosse, soccer, swimming and diving, track and field, volleyball, and wrestling; and girls: basketball, field hockey, gymnastics, lacrosse, soccer, softball, swimming and diving, track and field, volleyball, and cheerleading) using the High School Reporting Information Online (HS RIO) injury surveillance system. The HS RIO has been described elsewhere in detail.^28,32,33 In brief, high schools with at least one AT affiliated with the National Athletic Trainer’s Association who had a valid e-mail address were invited to participate. Athletic trainers from participating high schools received a small financial incentive to log onto the HS RIO Web site weekly throughout the academic year to report injury incidence and athletic exposure (AE) data. For each injury, ATs completed a detailed injury report form providing information on the injured athlete (eg, age, position played), the injury itself (eg, body site injured, diagnosis), and the injury event (eg, mechanism, activity at the time of injury). The number of schools reporting for each sport varied from 158 schools reporting girls’ basketball data to 27 schools reporting boys’ volleyball data. However, only boys’ volleyball and girls’ gymnastics had fewer than 50 schools reporting data; 12 of the 20 sports had over 100 schools reporting data. Injuries are defined as those resulting from participation in an organized high school athletic practice or competition and requiring medical attention from an AT. The surveillance system is designed to capture all time-loss injuries as well as any fracture, any concussion, and any dental injury, regardless of whether it resulted in restriction of the student athlete’s participation. This article focuses on concussions.

All concussions that (1) occurred during an organized high school athletic practice or competition, (2) resulted in the athlete receiving care from a medical provider, and (3) were brought to the attention of the AT were recorded. An AE was defined as one athlete participating in one organized high school athletic practice or competition, regardless of the amount of time played. All statistical analyses were performed using SPSS software (SPSS version 16.0, SPSS Inc, Chicago, Illinois). χ² analyses were performed for all categorical variables. Fisher exact test was used for comparisons among specialties, registered nurses, and physician assistants, given the relatively low numbers of their involvement. Logistic regression analyses were used to assess for associations between the dependent variable, the timing of return to play, and 2 independent variables: the type of provider returning the athlete to play and the duration of symptoms. The timing of return to play was collected as a categorical variable: 1 to 2 days, 3 to 6 days, 7 to 9 days, 10 to 21 days, and 22 days or more. Statistical significance was considered for P < .05.

We found that concussion accounts for nearly 15% of all sport-related injuries in US high schools. Our data suggest that when a high school athlete attending a school that employs an AT sustains a concussion, there is usually a medical professional on site at the time of injury. This is most often an AT. Interestingly, once we adjusted for potential confounders, there was no significant association between the type of medical provider who cleared the athlete to return to play and the timing of return to play. This suggests that ATs and physicians use similar return-to-play intervals when managing athletes who have sustained sport-related concussions.

Approximately 60% of concussions in our study were assessed by primary care physicians as opposed to sports medicine subspecialists. This is significant, as many primary care physicians may not have adequate resources or understanding of current concussion management practices. A survey by Pleacher and Dexter²⁴ revealed that many primary care providers are either unaware of current management guidelines or find the guidelines too confusing to put into practice. That same study revealed that only 16% had reliable access to neuropsychological testing within 1 week of an injury.²⁴ As our data suggest that many primary care physicians are called upon to care for concussive brain injuries, efforts to support them in this regard could have a major influence on management. Any changes in the recommendations on managing concussed athletes should be communicated directly to pediatricians, internists, and family practitioners. This could be accomplished by publishing sport-related concussion guidelines in medical journals that target these specialties and by increasing the number of sport-related concussion presentations at national conferences that target these specialties. Furthermore, our results show that orthopaedic surgeons and midlevel providers, such as nurse practitioners and physician assistants, are caring for an additional 8.2% of concussions. Targeting these clinicians, in addition to primary care physicians, when communicating concussion management recommendations may also result in significant improvements in care.

Nearly 1 in 5 concussed athletes received CT as part of their evaluation. Given the recent concern over radiation exposure in younger patients,^2,3,17,22 and the relatively low rates of structural intracranial injury resulting from high school sports,^14,25 this may represent an area for future improvement. Three percent of concussions were evaluated with MRI. As there is no radiation associated with this imaging modality, and MRI is superior in detecting traumatic lesions,²³ this might be a more favorable type of imaging, when indicated, for assessing traumatic sport-related brain injuries, especially after the acute period.²⁶ Athletes assessed by physicians were more likely to undergo neuroimaging and computerized neuropsychological testing than those athletes not assessed by a physician. This likely reflects, in part, confounding by indication: more severe injuries were more likely to be referred to a physician and more likely to warrant further testing. This is consistent with our findings, as athletes in our study with symptoms lasting longer than 7 days were more likely to have a physician decide when to return them to play.

Decisions to return the athlete to play were most often made by physicians and ATs. However, at least 2.5% of these decisions were made by nonmedical personnel. This number is likely higher for schools that do not employ ATs. The National Athletic Trainer’s Association reports that only 42% of high schools in the United States use the services of an AT.³⁶ As returning to play before symptom resolution can be associated with poor outcomes, such as second-impact syndrome,^6,30 efforts should be made to decrease the number of athletes being returned to play by nonmedical professionals. To that end, recent legislation in many states now requires that athletes suspected of sustaining a concussion be removed from play and held out until cleared by a medical professional.¹³ Some states require that coaches and other school personnel who work with athletes undergo specific concussion training.¹³ At the time of this writing, 28 states currently have specific concussion laws.²⁹

We have previously reported the percentage of concussions associated with various symptoms, the duration of concussion symptoms, the timing of return to play, and the frequency of computerized neuropsychological testing in the management of sport-related concussions.²¹ The distribution of reported symptoms, distribution by year in school, and timing of return to play were similar to our previous report,²¹ attesting to the reliability of the HS RIO surveillance system. Computerized neuropsychological testing was used in the evaluation of 41.2% of all concussions recorded, representing an increase of 15.5% from the 2008 to 2009 academic year.²¹ Given its rapid rise in usage in the high school setting, future research should focus on the use of computerized neuropsychological testing for the management of concussions in sports.

Interestingly, female athletes were more likely than male athletes to have symptoms that persisted longer than 7 days. This adds to previous literature that suggests more significant symptoms and poorer neuropsychological assessments in female athletes after sustaining sport-related concussions.^5,8,9,11

Several prior studies have suggested that men’s ice hockey carries the highest risk of sport-related concussion.^15,16,34 In a 16-year study of college athletes, Hootman et al¹⁵ reported that men’s ice hockey players sustained more concussions per 1000 AEs than football players. Similar conclusions were reached by other investigators.^16,34 Our analyses, however, demonstrate that although concussions represent a higher proportion of all injuries sustained by boys’ ice hockey players than other sports, American football had the highest rate of sport-related concussions per 100 000 AEs. This discrepancy may result from the increased attention focused on concussions in football.³¹ Such attention may have resulted in an increase in the diagnosis of concussion, as has recently been reported in the National Football League.²⁷

All schools included in the HS RIO have an AT who cares for their athletes. Therefore, we would not recommend generalizing our findings to high schools that do not employ ATs. In addition, concussion can be a difficult injury to diagnose, as there is no visible structural damage. Therefore, there may have been athletes who sustained a sport-related concussion but did not report it to the AT. While all concussions, dental injuries, and fractures brought to the attention of the AT were recorded, other injuries such as contusions, strains, and sprains were only recorded if they resulted in time lost from play. Thus, the percentage of all sport-related injuries accounted for by concussion would be smaller if minor injuries that did not result in time lost from play were included. Despite these limitations, this study reports findings from the largest national sample of athletes sustaining concussions in the US high school setting.

Concussions account for nearly 15% of all sport-related injuries in high school athletes. In US high schools that employ an AT, a medical professional is usually on site when a sport-related concussion occurs. The timing of return to play after a sport-related concussion is similar regardless of whether the decision to return the athlete to play is made by a physician or an AT. When a medical doctor is involved, most concussions are assessed by primary care physicians as opposed to subspecialists. Computed tomography is obtained during the assessment of 1 of every 5 concussions occurring in high school athletes.