Lou Gehrig may not have died from Lou Gehrig's disease. That is a scenario made possible by new research that provides more clues to the possible link between head trauma, like sports concussions, and his namesake disease, also known as amyotrophic lateral sclerosis, or ALS. The findings also provide direct evidence that repeated blows to the head are a cause of motor neuron diseases, where patients lose control over voluntary muscle movements.

Scientists at Boston University's Center for the Study of Traumatic Encephalopathy (CSTE) studied the brains and spinal cords of twelve deceased former athletes who had suffered multiple concussions during their playing days. They and their families had donated their remains to CSTE's Brain Bank to be used for research, funded by the National Football League.

Dr. Ann McKee, neurology professor at BU's School of Medicine, had been curious why so many former athletes, especially NFL players, had been diagnosed with ALS at a rate far above that of non-athletes.

Of the twelve athletes studied, three had been diagnosed prior to their death with ALS, including former professional football players Wally Hilgenberg and Eric Scoggins, as well as a former professional boxer, who wished to remain anonymous. McKee found a toxic protein in all twelve athletes, which causes chronic traumatic encephalopathy (CTE), a disease linked to head injuries that causes cognitive decline, abnormal behavior and dementia. In the three athletes diagnosed with ALS, the protein was found not only in their brains but also in their spinal cord. In previous research, she had not seen this protein in the spinal cords of non-athletes who died of ALS.

This discovery led her to the conclusion that these three athletes died of a disease similar to but somewhat different than ALS. Her team named the new condition chronic traumatic encephalomyopathy (CTEM).

People are being misdiagnosed clinically while they're alive as having ALS when in fact they have a different motor-neuron disease, Dr. Robert Stern, who serves with McKee as co-director of CSTE, told the New York Times. Scientists will be able to get at a faster understanding of the disease in general, and therefore effective treatments, by knowing more about who's at risk and who's not.

The research will be detailed in the September issue of the Journal of Neuropathology and Experimental Neurology.

Now, the question being asked by fans of Gehrig is whether he actually had CTEM and not traditional ALS. After playing football at Columbia University and enduring at least five documented baseball concussions, some are wondering if head injuries caused his condition.

Here he is, the face of his disease, and he may have had a different disease as a result of his athletic experience, McKee said.

If nothing else, this clinical connection between concussions and serious brain disease later in life should give parents and athletes even more motivation to take head injuries seriously.

Dan Peterson writes about sports science at Sports Are 80 Percent Mental.

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