Lou Gehrig's Disease

Lou Gehrig’s Disease is also known as amyotrophic lateral sclerosis, or ALS. The meaning is broken down in the word:
“'a' – without"
“'myo' – muscle"
“'trophic' – nourishment"
“'lateral' – side of the spinal cord"
“'sclerosis' – hardening/scarring"

Amyotrophic means that the muscles have lost their nourishment and they become smaller and weaker. Lateral means that the disease affects the sides of the spinal cord, which is where the nerves that nourish the muscles are located. Sclerosis means that the diseased part of the spinal cord develops scarred tissue where the healthy nerves would have been.

ALS is called Lou Gehrig’s disease because Lou Gehrig was a hall of fame baseball player who played for the New York Yankees and was diagnosed with ALS in the ‘30s.

"Lou Gehrig's Disease (ALS)"
http://kidshealth.org/kid/grownup/conditions/als.html