Lou Gehrig earned the nickname the Iron Horse for good reason. The baseball player took the field no matter what—with a broken thumb, with a broken toe, while suffering from lumbago or even a concussion. During his career, the slugger experienced at least three concussions, a common injury for professional athletes. Oftentimes athletes continue to play while suffering from a concussion and in recent years former pro athletes frequently have been diagnosed with neurological conditions such as amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig's disease. A recent study published in Journal of Neuropathology and Experimental Neurology finds a link between concussions and a disease similar to ALS.
ALS is a rare, rapidly progressing neurological disorder that cripples motor neurons, which tell the body what muscles to move. Impaired motor neurons fail to communicate, leading to an inability to walk, gesture, talk, and eventually breathe. Teammates of Gehrig first noticed a problem when he dragged his feet instead of lifting them to walk. Most patients die from respiratory failure within three to five years of the onset of symptoms.
Ann McKee, associate professor at Boston University School of Medicine, and her colleagues looked at the brain and spinal cord of two former professional football players and one boxer—all of whom had been diagnosed with ALS prior to death. The researchers discovered that all three had very high amounts of a protein TDP-43. The protein lives in the nucleus of nervous system cells, but in the three patients TDP-43 seeped out of the cells, flooding the brain and spinal cord. The excessive amounts of TDP-43 caused symptoms like ALS, but also indicated to researchers that the athletes did not suffer from the disease.
McKee cannot speculate as to whether Gehrig actually suffered from Lou Gehrig's disease, because she has not examined his body (and there are no plans to do so). But the results confirm a suspicion that repeated head trauma leads to serious neurological conditions, which mimic serious diseases such as ALS or Alzheimer's.
[Via The New York Times]