Concussions in High School Sports: Study Sheds New Light On Causes, Symptoms and Management

A new study confirms that football is still responsible for the majority of concussions at the high school level and that the symptoms of concussion clear in most cases within one week, but also shows for the first time the important role computerized neuropsychological testing is playing in concussion assessment and return to play decisions.  

Key findings

Reviewing data reported by certified athletic trainers (ATs) through an Internet-based injury surveillance system on concussions in nine high school sports (football, boys' soccer, girls' soccer, boys' basketball, girls' basketball, wrestling, baseball, volleyball, and softball), researchers at Children's Hospital, Boston, and the Nationwide Children's Hospital in Columbus, Ohio, made the following key findings: 

• Majority of concussions in football.  Football still accounts for more than half (56.8%) of all concussions, with girl's soccer (11.9%), wrestling (7.4%), girls' basketball (7.0%) and boys' soccer (6.6%) rounding out the top five (note: an even more recent 2011 study, which includes three new sports (boys and girls lacrosse and cheerleading) lists the top five as football: 53.1%, boys lacrosse (9.2%), girls soccer (7.4 %),  cheerleading (4.9%), and wrestling (4.6%);
• Most concussions result from player-to-player contact.  Three out of four (76.2%) concussions were caused by contact with another player, followed by contact with the playing surface (15.5%) and contact with playing apparatus (7.7%).  Of the player-to-player contact, the most common type was head-to-head collisions (52.7%), followed by collisions between the head of the injured athlete and a different body part of another player (38.9%), and contact between the injured athlete's head and the playing surface after player-to-player contact (8.4%).  Of the 101 concussions that occurred in soccer, none were due to contact with the ball when the athlete was purposefully heading the ball.
• For most, concussion symptoms clear within a week.
  • 27.0% had symptoms resolve in less than 24 hours;
  • 36.2% between 1 and 3 days;
  • 20.2% between 4 and 6 days;
  • 15.1% had symptoms lasting more than a week but less than a month; and
  • 1.5% were still experiencing symptoms more than a month after injury.

• Use of computerized testing on the rise, but less in football.  Despite being a relatively new diagnostic tool, computerized neuropsychological testing was used to assess one out of four (25.7%) concussions (just a year later, that number has risen to 40%) although injured football players were less likely to have computerized neuropsychological testing in evaluating their concussions than athletes injured in other sports;
• Where computerized testing used, more conservative return to play.  Athletes evaluated using computerized neuropsychological testing were less likely to return to play on the same day, and less likely to return to play within a week of their injury, than the three out of four injured athletes who did not undergo such testing;
• Headache the most common concussion symptom by far.  More than nine out of ten (93.4%) of concussed athletes experienced a headache, with dizziness/unsteadiness (74.6%), difficulty concentrating (56.6%), confusion/disorientation (46.0%) and vision changes/sensitivity to light (37.5%) the next most common reported symptoms.  A quarter of athletes (24.3%) reported amnesia, but loss of consciousness was uncommon, occurring in less than 5% of concussions, less than half the 10-11% reported in previous studies. 
• Concussions evenly split among grades: There was no statistically significant difference in concussion rates by grade, with freshmen (24.8%) and juniors (28.1%) only slightly more likely to suffer concussion than sophomores (24.4%) and seniors  (22.6%)
• Players on varsity teams suffered half of concussions (51.7%), followed by those playing junior varsity (30.1%) and on freshman teams (13.8%);
• Most concussions occur in competition (68.5%) than practice (31.5%); and
• Vast majority (89.5%) were first concussions. This is consistent with a 2011 study¹ finding that repeat concussions in 12 sports (six boys' and six girls') represented 11% of all concussions reported over an 11-year period in a large public high school system.

Effect and use of computerized neuropsychological testing

Researchers offered several possible explanations for their findings that athletes evaluated with computerized neuropsychological testing were less less likely to return to play on the same day, and less likely to return to play within a week of their injury:

1. More reliable than self-reporting of symptoms: Despite reporting that their symptoms had cleared, the athletes' performance on the tests revealed deficits in neurocognitive function, a finding that provides further proof of the benefit of such testing in the management of sports-related concussion shown in previous studies;
2. Lead to more conservative management: Clinicians who use computerized neurocognitive testing are more conservative in their management, and thus less likely to return athletes to play on the same day or within the same week as their injury;
3. Used more often in cases of severe concussion: Athletes deemed to have more severe injuries were more likely to undergo neurocognitive testing.

Likewise, the authors offered several possible explanations for the finding that injured football players were less likely to have computerized neuropsychological testing than other injured athletes:

First, schools with limited financial resources are more likely to have football programs, given its popularity, than they are to have other sports;

Second, they may not have the resources to purchase computerized test programs; and,

Third, football programs may be reluctant to use such testing in the assessment of a concussion for fear that athletes may miss more playing time.

Concussion education efforts working

Seeking to explain their finding that loss of consciousness was far less common than reported in previous studies, the study's authors suggested a "change over time in the understanding of sport-related concussion"  as one possible explanation. They noted that, as recently as 2007, more than four out of ten (42%) youth coaches surveyed believed a concussion only occurred when an athlete loses consciousness, but that in 2009, in a study of parents of young rugby players, 95% reported knowing that a player did not need to be "knocked out" to have suffered a concussion.

Their conclusion: "The percentage of diagnosed concussions associated with a loss of consciousness is likely decreasing, as the athletic community learns that loss of consciousness is not necessary for concussion diagnosis."

For the most comprehensive, up-to-date concussion center on the Internet, click here.

Source:  

1. Lincoln A, Caswell S, Almquist J, Dunn R, Norris J, Hinton R. "Trends in Concussion Incidence in High School Sports: A Prospective 11-Year Study" Am. J. Sports Med.2011;30(10) accessed January 31, 2011 @ http://ajs.sagepub.com/content/early/2011/01/29/0363546510392326.full.pdf+html

2. Meehan WP, d'Hemecourt P, Collins C, Comstock RD, Assessment and Management of Sport-Related Concussions in United States High Schools. Am. J. Sports Med. 2011;20(10)(published online on October 3, 2011 ahead of print) as dol:10.1177/0363546511423503 (accessed October 3, 2011).