What is ALS?

Amyotrophic lateral sclerosis (ALS), often known as “Lou Gehrig’s disease,” is a progressive neurodegenerative disease that affects nerve cells in the brain and spinal cord. Motor neurons travel from the brain to the spinal cord and from the spinal cord to muscles throughout the body. Over time, the progressive degeneration of motor neurons produced by ALS leads to their death. When motor neurons die, the brain loses the ability to initiate and control muscle movement. Due to the progressive effect on voluntary muscle action, patients in the final stages of the disease may become totally paralyzed.

A-myo-trophic comes from the Greek. “A” means without or lacking. “Mio” refers to the muscles, and “trophic” means feeding: “No feeding to the muscles.” When a muscle is not fed, it “atrophies” or wears out. “Lateral” identifies the areas of the spinal cord where parts of the nerve cells that signal and control muscles are located. As this area degenerates, scarring or hardening (“sclerosis”) occurs in the region.

As motor neurons degenerate, they stop sending impulses to muscle fibers that normally result in muscle movement. The first symptoms of ALS often include increased muscle weakness, especially in the arms and legs, in speech, swallowing, or breathing. When muscles stop receiving the motor neuron messages they need to function, they begin to atrophy (get smaller). The extremities begin to look “thinner” as the muscle tissue atrophies.

Nerve Cells
Cell body
Axon
Atrophied muscle
Muscle
ALS-affected nerve cell and muscle

Normal nerve cell and muscle

Nerve cells Cell
body
Axon Atrophied
muscle
Muscle
Nerve cells and muscles affected by ALS
Normal nerve cell and muscle

What types of nerves make the body function properly?

The body has many kinds of nerves. There are those involved in the thought process, memory, and in the detection of sensations (such as hot or cold, sharp or blunt, etc.), and others for vision, hearing, and other bodily functions. The nerves that are affected by ALS are the motor neurons that produce voluntary movements and muscle force. Examples of voluntary movements are making an effort to reach for the phone or get off the sidewalk; these actions are controlled by the muscles of the arms and legs.

The heart and digestive system are also made of muscle, but of a different kind, and their movements are not under voluntary control. When the heart beats or a meal is digested, everything happens automatically. Therefore, the heart and digestive system are not involved in ALS. Breathing also appears to be involuntary. Remember, though, that while you can’t stop your heart, you can hold your breath, so keep in mind that ALS may affect your breathing over time.

Although what causes ALS is not fully understood at this time, a new body of scientific understanding regarding the physiology of this disease has been gained in recent years.

While there is currently no cure or treatment to stop or reverse ALS, there is an FDA-approved drug, riluzole, that modestly slows the progression of ALS, as well as several other drugs in clinical trials that offer hope.

It is important to know that there are significant devices and therapies that can control ALS symptoms that help people maintain as much independence as possible and prolong survival. It is important to remember that ALS is a fairly variable disease; no two people lead the same life or have the same experiences. There are medically documented cases of people in whom ALS ‘runs out’, stops progressing or progresses very slowly. No matter what your individual course or situation may be, the ALS Association and your medical team are there for you.

For more personal stories from people living life to the fullest, click here. In the words of one man: “I have made ALS a part of my life, not my whole life”.