Late functional deterioration following paralytic poliomyelitis.

Many patients with previous poliomyelitis develop 'post-polio syndrome' (PPS) in which late functional deterioration follows a period of relative stability. The frequency with which PPS can be attributed to clearly defined causes remains uncertain. We reviewed 283 newly-referred patients with previous poliomyelitis seen consecutively over a 4-year period; 239 patients developed symptoms of functional deterioration at a mean of 35 (5-65) years after the paralytic illness. Functional deterioration was associated with orthopaedic disorders in 170 cases, neurological disorders in 35, respiratory disorders in 19 and other disorders in 15. Progressive post-polio muscular atrophy was not observed. Functional deterioration following paralytic polio-myelitis is common, and associated with orthopaedic, neurological, respiratory and general medical factors which are potentially treatable.