NPTE Neurological Practice Test

Postpolio syndrome is defined by the appearance of new, slowly progressive weakness after a long period of stability following the original polio infection. After poliomyelitis, surviving motor neurons sprout to reinnervate muscles, which allows recovery, but those enlarged motor units can later deteriorate or fail, leading to renewed weakness and reduced endurance years or decades after the initial illness. This late, gradual decline is the hallmark, and it’s not an acute relapse, nor is it primarily about respiratory failure or cognitive changes—although respiratory muscles can be affected, the defining feature is the new, progressive weakness after a stable interval. Patients often also notice fatigue, muscle atrophy, joint or muscle pain, and sleep disturbances, especially in previously involved muscles.