E.D. Zemper Exercise Research Associates of Oregon, Eugene, OR


Injury and exposure data were collected on a weekly basis during the 1997 season from certified athletic trainers at a representative national sample of 56 high school and 46 college football teams. The data allowed investigation of a number of questions, including defining the relative risk of sustaining a concussion for players with a history of concussion compared with players with no history. These data included 8782 player-seasons (4311 HS, 4471 college), 612,527 athlete-exposures in games and practices (297,390 HS, 315,137 college) and a total of 360 reported concussions (157 HS, 203 college). Cerebral concussion was the second most frequent injury reported at the HS level, exceeded only by ankle sprains, and the third most frequent for college players, following ankle sprains and knee ligament sprains/tears. While direct impact from another player’s helmet was the cause of 16-26% of all time-loss injuries, helmet-to-helmet contact was the cause of 56-76% of all concussions. The average time-loss for a Grade 1 concussion (American Academy of Neurology classification) was 4.4 d, for Grade 2 it was 13.6 d and for Grade 3 it was 10.3 d. In calculating the relative risk, data from 9 teams (2 HS, 7 college) were deleted because of incomplete history data. In the HS sample, 4.3% of the players had a history of concussion during the previous 5 years, while 10.4% of the college players had a previous history. Combining HS and college data, 74 of 534 players with a previous history (13.9%) had a concussion during the season, and 232 of 7473 players with no history (3.1%) suffered concussions. The calculated relative risk is 4.5, indicating that a player with a history of cerebral concussion during the previous 5 years is 4.5 times as likely to sustain a concussion as a player with no history.

This project is funded by Riddell Inc.