Jan. 31, 2003 -- For teenage athletes, even mild concussions can cause memory problems lasting up to a week. The first study of its kind evaluates the effects of and recovery from mild head injuries in high school sports. The short-term effects are more serious than most people realize, scientists say.
The lack of research on high school athletic injuries is "alarming," writes lead researcher Mark R. Lovell, PhD, with the orthopaedic and neurological surgery department at the University of Pittsburgh Medical Center. His study appears in this month's Journal of Neurosurgery.
"This study demonstrates that even in this more mildly injured group, there can be pronounced memory decline," which remains at least seven days after injury, he says.
Concussions are head injuries caused by a blow to the head and can result in brain damage. Sometimes a victim suffers varying states of consciousness, or none at all. There also may be confusion, dizziness, and memory loss.
Victims of mild concussion are typically high school athletes between ages 13 and 18 who play contact sports, suggesting greater vulnerability to severe injury in that age group, Lovell points out. Mild concussions are the most common types of concussions and are frequently overlooked or unrecognized because the player often returns to play during the same game or match.
Animal studies have shown that changes in brain chemistry persist seven days or more after mild injury. Studies have also suggested that if the brain has not had time to heal, it will be more susceptible to further, more serious damage. But current return-to-play guidelines frequently used nationwide suggest a player return to the field after mild concussions if symptoms disappear after 15 minutes.
In his study, Lovell looks at 64 high school athletes -- 60 boys and four girls who had suffered concussion during football, basketball, soccer, and other sports. The control group was composed of 22 swimmers and two football players who had not been injured.
Athletes saw doctors 36 hours, four days, and seven days after their injuries occurred. Doctors classified their mild concussions as more severe and less severe based on how long their mental state was altered on the field. The more severe group had amnesia and disorientation for more than five minutes while the less-severe group had no change in mental state, or changes that lasted less than five minutes.
The less-severe group suffered significant declines in memory at 36 hours, but not at the seven-day mark. The more severe-injury group reported more symptoms of memory loss at 36 hours and at day four.
In high school athletics, "concussions that involve a loss of consciousness almost always result in immediate removal from competition and restriction of return to play for at least one week," writes Lovell.
"Concussions that do not involve a loss of consciousness have historically been viewed as a more trivial injury and athletes have often returned to play during the same contest," he adds. "Although concussion without loss of consciousness is the most common type of sports-related head injury, it is more difficult to detect and may often be misdiagnosed by sports medicine practitioners."