It is a response to polio, rather than a part of it. People with post polio syndrome can have fatigue , muscle and joint pain, and muscular atrophy. Atrophy means a wasting or decrease in the size of muscles. People with PPS have progressive muscle weakness. Sometimes the muscles in the spine atrophy and the symptoms mimic amyotrophic lateral sclerosis , or ALS, also known as Lou Gehrig's disease.
Some people also have an intolerance to cold, and trouble with swallowing, breathing, and sleeping.
The cause of PPS is the death of individual nerve terminals in the motor units that remain after a bout of polio. The deterioration may actually result from the process of recovery from polio. During recovery, surviving motor neurons sprout new endings. This allows the body to regain function. The motor units become large and add stress to the body.