A-myo-trophic comes from the Greek language. A means no or negative. Myo refers to muscle, and Trophic means nourishment–No muscle nourishment. When a muscle has no nourishment, it atrophies or wastes away. Lateral identifies the areas in a persons spinal cord where portions of the nerve cells that signal and control the muscles are located. As this area degenerates it leads to scarring or hardening (sclerosis) in the region. 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. The average life expectancy following diagnosis is two to five years, but many people can live beyond that timeframe. Up to 10 percent will live an additional 10 years or more; five percent will live 20 years more. Famed scientist Stephen Hawking, 72, was diagnosed with the disease in 1963.
Posted on: Thu, 21 Aug 2014 02:03:50 +0000
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