The rate of concussions sustained during high school football practice has decreased over the past 5 years, while the rate of concussions sustained in competition during regular football game season has increased during the same period, according to a study published in Pediatrics.
The aim of this descriptive epidemiological study were to analyze high school concussion rates during the between 2013 and 2018, assess differences in concussion rate for sex-comparable sports, and evaluate temporal trends in concussion timing.
Data were obtained from the National High School Sports-Related Injury Surveillance Study using the High School Reporting Information Online database. Sports analyzed included boys football, wrestling, soccer, basketball, cross country, ice hockey, lacrosse, swimming and diving, track and field, and baseball as well as girls volleyball, soccer, basketball, cross country, field hockey, lacrosse, swimming and diving, track and field, cheerleading, and softball.
The database contained weekly reports from high school athletic trainers regarding injury incidence and athlete exposure. Detailed injury reports including body part affected, diagnosis, mechanism, activity, position, and recurrence were also included. A reportable exposure was defined as 1 athlete participating in 1 practice or competition. Inclusion criteria for concussion included 1) an injury which occurred during practice or competition, 2) an injury which required medical attention, and 3) a reported diagnosis of concussion.
Of the 9542 concussions reported, 63.7% occurred during competition and 36.3% occurred during practice sessions. Concussion frequency was higher during the regular season (81.6%) than during preseason (14.2%), and 3.3% of concussions occurring during the postseason.
There were 22,870,364 athlete exposures, resulting in an overall concussion rate of 4.17 per 10,000 athlete exposures. Sports with the highest overall concussion rates were boys’ football (10.40 per 10,000 athlete exposures), girls’ soccer (8.19 per 10,000 AEs), and boys’ ice hockey (7.69 per 10,000 athlete exposures). Concussion rates were higher in competition vs practice (10.37 vs 2.04 per 10,000 athlete exposures), with the exception of girls’ cheerleading, where concussions occurred more frequently in practice. Analysis of sports by gender revealed that the rate of concussion was higher in girls than boys for sex-comparable sports (3.35 vs 1.51 per 10,000 athlete exposures).
An analysis of timing of concussions during practice found 66.9% occurred after the first hour of practice and in sports with quarters or halves, investigators found 54.5% of concussions occurred in the second half or third/fourth quarter of practice games.
Assessment for mechanism of injury revealed 62.3% were caused by athlete-to-athlete contact, 17.5% by athlete-to-surface contact, and 15.8% by athlete-to-equipment contact. Recurrent concussions occurred more frequently in girls than boys (9.3% vs 6.4%) in sex-comparable sports. Overall, the highest rates of concussion recurrence were in boys’ ice hockey (14.4%), boys’ lacrosse (12.1%), and girls’ field hockey (12.1%). Over the study periods, a decrease in recurrent concussions across all sports (average -0.03 per 10,000 athlete exposures) was found, with the greatest decrease in boys’ football (-0.13 per 10,000 athlete exposures).
Limitations of the study included the use of data from only high schools with athletic trainers and potential underreporting of injury or symptoms by athletes. The use of 1 practice or 1 competition for the definition of an athlete exposure rather than time spent in athletic activity may have further limited these findings.
The researchers concluded “football remained the high school sport with the highest concussion rate, with decreasing practice concussion rates observed.” They also note that “decreasing recurrent concussion rates may be associated with changes in concussion diagnosis and management in high school sport settings.”
Kerr ZY, Chandran A, Nedimyer AK, Arakkal A, Pierpoint LA, Zuckerman SL. Concussion incidence and trends in 20 high school sports [published online October 15, 2019]. Pediatrics. doi: 10.1542/peds.2019-2180