Many athletes reported symptoms often used to diagnose concussions, even though they did not suffer a head injury, a new study has found.
The findings suggest that some symptoms, such as fatigue and neck pain, could be attributed to intense exercise rather than a brain injury.
The research raises new questions about the Sport Concussion Assessment Tool (SCAT), a questionnaire widely used along with other methods to diagnose concussions in sport.
“Our findings highlight the importance of considering the effects of exercise and fatigue in assessing concussion in athletes on the field,” said the study’s first author, Stephanie Iring, a doctoral candidate in the laboratory of Jorge Serrador at Rutgers University in Newark, New Jersey, and Western Sydney University in Australia.
“While players with a head impact may report more symptoms generally, we have to be cautious in using all symptoms [on the assessment] since some are common after intense exercise even when there was no head impact.”
Iring presented the findings at the recent American Physiological Society annual meeting in Philadelphia.
A concussion is a type of traumatic brain injury usually caused by a blow to the head. Although concussions are not typically life-threatening, their effects can be serious and long-lasting. About 3.8 million sports-related concussions are reported each year in the United States.
SCAT is a tool for medical professionals to determine if a player suffered a concussion. It includes questions about “red flag” symptoms such as neck pain, headache, muscle weakness and vision problems in addition to tests used to assess memory loss and other symptoms.
In most previous studies of the tool, researchers compared symptoms in athletes who experienced a blow to the head with people who have been at rest.
For the new study, researchers compared SCAT scores in rugby players who had sustained a blow to the head with team-mates who had just played an intense rugby match but did not have a head impact.
In total, they assessed 209 players, 80 of whom had experienced a head impact and 129 who had not. For the study, the researchers used the SCAT3 version of the SCAT assessment.
Compared with those who did not have a head injury, head-injured players had significantly more symptoms on the SCAT assessment than other players, reporting 26 symptoms on average. Non-injured players reported about nine symptoms. However, many players without a head injury had symptoms that were similar to those reported by head-injured players, including fatigue and neck pain.
“Our data shows that exertion during a match increased the number and severity of self-reported symptoms in control players, even though they had not experienced a head impact,” Iring said. “This could lead to difficulty differentiating these players from those that had experienced a head impact when using on-field assessments.”
Some symptoms, including headache and “not feeling right,” were more closely associated with having a head injury, suggesting these symptoms might be a stronger indicator of concussion in players that have just finished an intense game, according to researchers.
In addition to headache, other symptom categories that were more common in those with a head injury included cognitive-sensory effects, emotional-affective symptoms and hypersensitivity. The researchers suggested that further studies are needed to examine how these components can be used along with current physiological measures to better assess a concussion in athletes.