Back in November, Dr. Michael L. Lipton of the Albert Einstein College of Medicine presented a study at the annual meeting of the Radiological Society of North America, suggesting that youth athletes who often "head" soccer balls experience similar brain abnormalities as those found in patients with traumatic brain injuries.

Before declaring soccer "headers" to be enemies in the ongoing battle against youth concussions, New York-based pediatrician Dr. Ann R. Punnoose urges caution when interpreting the findings of Lipton's study in a recent perspective for the Journal of the American Medical Association.

Lipton found that "repetitive heading could set off a cascade of responses that can lead to degeneration of brain cells," placing that threshold somewhere between 1,000 and 1,500 headers in a year. Once players surpassed that amount, they experienced brain changes "that look like traumatic brain injury," Lipton and his colleagues discovered.

But as Punnoose notes, Lipton's study had a small sample size of 38 participants and relied on those subjects' retroactive recounting of their own headers.

In other words: There's plenty more work to do before conclusively linking soccer headers with brain injuries, in the eyes of Punnoose and others.

"Before any guidelines about heading are created or changed, researchers have to be sure that the changes found on DTI were, in fact, indicative of changes in the players' neurocognitive performance and not incidental findings in all soccer players irrespective of heading frequency," says Dr. Stanley Herring, co-director of the Seattle Sports Concussion Program, in the JAMA piece.

Frank Webbe, a professor of psychology at the Florida Institute of Technology, told Punnoose that "the concept of thresholds may not fully capture the complexity of the effect of heading on different players."

This leads Punnoose to conclude, "Until researchers proceed with better studies that determine exactly how heading affects the brain, whether the practice might pose a risk to children remains an open question."

With the increasing scrutiny of concussions in youth sports, one can assume it'll only be a matter of time before researchers take up Punnoose's challenge.

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