Motor Neuron Disease
Inherited forms of motor neuron disease are caused by genetic mutations or deletions that cause degeneration of motor neurons. Motor neurons are the cells that control essential muscle activity.
Hereditary motor neuron disease includes a group of childhood disorders known as the spinal muscular atrophies.
Nonhereditary (also called sporadic) motor neuron diseases are caused by unknown factors. However, scientists believe that environmental toxins or viruses could act as disease triggers. Nonhereditary motor neuron diseases include:
- ALS (also known as Lou Gehrig's disease)
- Progressive bulbar palsy
- Pseudobulbar palsy
- Primary lateral sclerosis
- Progressive muscular atrophy
- Post-polio syndrome.
There are no specific tests to diagnose motor neuron disease.
(Click Amyotrophic Lateral Sclerosis for more information about the cause of this disease.)
There is no cure or standard treatment for motor neuron disease. Physical therapy, occupational therapy, and rehabilitation are designed to:
- Improve posture
- Prevent joint immobility
- Slow muscle weakness and wasting (atrophy).
Stretching and strengthening exercises can help:
- Reduce spasticity
- Increase range of motion
- Keep circulation flowing.
Additional therapy for speech, chewing, and swallowing may be required.
Riluzole is the only prescribed drug approved by the U.S. Food and Drug Administration (FDA) to treat ALS. Although riluzole prolongs life by 2 to 3 months, it does not relieve symptoms.
(Click ALS Symptoms to learn more about the symptoms of amyotrophic lateral sclerosis.)
Other medications for motor neuron disease include:
- Muscle relaxants, such as baclofen and tizanidine
- Benzodiazepines to reduce spasticity
- Glycopyrrolate and atropine to reduce the flow of saliva
- Quinine or phenytoin to decrease muscle cramps
- Anticonvulsants and nonsteroidal anti-inflammatory drugs (NSAIDs) for pain
- Drugs to treat depression.
Stronger medication, such as morphine, may be needed to cope with musculoskeletal abnormalities or pain that appears in the later stages of this disorder.