Introduction : We examined the characteristics of paralytic scoliosis using plain radiography.Subjects and methods : We recruited fourteen patients aged ≥ 15 years old with no history of bone surgery at the time of their final observation. Participants included those who had cerebral palsy or those who had a history of encephalitis and underwent spinal frontal plain radiography in the supine position at different time points. We evaluated gross motor function, position and direction of the curve, Cobb angle, rate of variability, and degree of progression at 5-year intervals. We measured the percentage of migration using hip frontal plain radiography to assess hip dislocation.Results : The final Cobb angles were 82.0°, 118.4°, and 92.3°for the thoracic, thoracolumbar (TL), and lumbar curvatures, respectively. TL curvatures showed the greatest progression, although this was not statistically significant. The progression was greatest in the 10-15-year age group (12.5°annually). The final Cobb angles in the hip dislocation, subluxation, and no dislocation groups were 102.8°, 108.8°, and 87.5°, respectively；the difference was not statistically significant. No relationship was observed between the location or progression of curvature and the state of the hip location.Discussion : Paralytic scoliosis progressed most rapidly in 10-15-year-old patients, especially in those with TL lesions. We did not detect any relationships between hip dislocation and Cobb angle, but these parameters progressed at different rates in different patients.