Arthur M. Carlin, MD

As many as 300,000 sportsrelatedconcussions arediagnosed each year inthe United States.1 Thisfigure underestimatesthe true incidence, however, becausemany concussive injuries are notrecognized by the injured persons,trainers, or physicians. A recentstudy found that 4 of 5 professionalfootball players with concussionwere unaware that they had sufferedthis injury.2