Concussion Grading Systems - American Academy of Neurology Guidelines

American Academy of Neurology Guidelines

The guidelines devised in 1997 by the American Academy of Neurology (AAN) are based on those by the Colorado Medical Society. According to these guidelines, a grade I concussion is associated with no loss of consciousness and symptoms of confusion last less than 15 minutes. Grade II is the same, except symptoms last longer than 15 minutes. In grade III, loss of consciousness does occur. Grade III can be further divided into grades IIIa and IIIb, with brief loss of consciousness (measured in seconds) and prolonged loss of consciousness (measured in minutes) respectively. According to the AAN, permanent brain injury can occur with either Grade II or Grade III concussion.

By these guidelines, an athlete suffering a single, grade I concussion is given a neurological evaluation every five minutes starting immediately after the injury and may return to the competition if signs and symptoms resolve within a quarter of an hour. Otherwise, the return to play rules are the same for the AAN and Colorado Medical Society guidelines.