We reviewed the cases of 110 patients with paralytic scoliosis due to poliomyelitis who were operated on. In the lumbar region, anterior Dwyer instrumentation with posterior fusion gave excellent correction of scoliosis and pelvic obliquity. In the more rigid thoracic curves, combined anterior Dwyer instrumentation and posterior fusion gave better results than posterior fusion alone, but had more morbidity. Long c-shaped curves benefited more from a combined anterior Dwyer procedure at the apex of the curve and long posterior Harrington instrumentation. Traction was found to be of use only in rigid curves and in those larger than 80 degrees. With combined anterior and posterior fusion, there was a pseudarthrosis rate of 7 per cent in lumbar curves, none in thoracic curves, and 12.5 per cent in long c-shaped curves. The pseudarthrosis rate rose to more than 25 per cent in patients who had a posterior fusion alone.