Roosevelt was left permanently paralyzed from the waist down and was diagnosed with polio. Historians have noted a 2003 study strongly favoring a diagnosis of Guillain–Barré syndrome,[98] but have continued to describe his paralysis according to the initial diagnosis.[99][100][101][102]

Rare photograph of Roosevelt in a wheelchair, with Fala and Ruthie Bie, the daughter of caretakers at his Hyde Park estate. Photo taken by his cousin Margaret Suckley (February 1941).
Though his mother favored his retirement from public life, Roosevelt, his wife, and Roosevelt's close friend and adviser, Louis Howe, were all determined that he continue his political career.[103] He convinced many people that he was improving, which he believed to be essential prior to run for public office again.[104] He laboriously taught himself to walk short distances while wearing iron braces on his hips and legs by swiveling his torso, supporting himself with a cane.[105] He was careful never to be seen using his wheelchair in public, and great care was taken to prevent any portrayal in the press that would highlight his disability.[106] However, his disability was well known before and during his presidency and became a major part of his image. 