A series of 20 cases of megacolon with spasm of the rectosigmoid in children is reported. Ovar Swenson was on staff at Boston Children's Hospital and had been treating many children with Hirschsprung's disease as well as performing colonic manometric studies on a number. He describes one key case, a six-year-old boy where he used a diverting colostomy, which ‘cured’ the child and was unable to show any sign of peristalsis in the distal limb. Barium studies invariably showed the distal segmental contractions right down to the anus. Barium studies invariably showed distal segmental contractions right down to the anus.