Amyotrophic lateral sclerosis (ALS), often referred to as “Lou Gehrig’s Disease,” is a progressive neurodegenerative disease that affects nerve cells in the brain and the spinal cord. Motor neurons reach from the brain to the spinal cord and from the spinal cord to the muscles throughout the body. The progressive degeneration of the motor neurons in ALS eventually leads to their death. When the motor neurons die, the ability of the brain to initiate and control muscle movement is lost. With voluntary muscle action progressively affected, patients in the later stages of the disease may become totally paralyzed.
As motor neurons degenerate, they can no longer send impulses to the muscle fibers that normally result in muscle movement. Early symptoms of ALS often include increasing muscle weakness, especially involving the arms and legs, speech, swallowing or breathing. When muscles no longer receive the messages from the motor neurons that they require to function, the muscles begin to atrophy (become smaller). Limbs begin to look “thinner” as muscle tissue atrophies.
Although the cause of ALS is not completely understood, the recent years have brought a wealth of new scientific understanding regarding the physiology of this disease.
While there is not a cure or treatment today that halts or reverses ALS, there is one FDA approved drug, Riluzole, that modestly slows the progression of ALS as well as several other drugs in clinical trials that hold promise.
For more information about ALS please see:
ALS Association: http://www.alsa.org/als/what.cfm
University of Cincinnati Health Library: http://healthadministration.uc.edu/news-and-resources/articles/health-library-amyotrophic-lateral-sclerosis