Background: Familial dysautonomia (Riley-Day syndrome) is an autosomal recessive disorder primarily affecting individuals of Ashkenazi Jewish extraction. It affects the autonomic, central, and peripheral nervous systems. Spinal deformity (mainly scoliosis) is the most common orthopaedic problem in patients with familial dysautonomia. The objectives of our study were to document the prevalence of spinal deformity in a referral center for familial dysautonomia and to determine the effectiveness of bracing. Methods: We performed a retrospective radiographic and clinical study of 123 patients with familial dysautonomia who had survived to the age of twenty years or older. Results: One hundred and two (83 percent) of the 123 patients had spinal deformity: sixty-nine (56 percent) had scoliosis only, thirty-one (25 percent) had scoliosis as well as kyphosis, and two (2 percent) had kyphosis only. Scoliosis was diagnosed by the age of ten years in sixty-four (52 percent) of the patients. Of the sixty-five patients who were treated with bracing, fifty-eight (89 percent) had progression and twenty-four (37 percent) underwent spinal arthrodesis. No risk factors for the presence or progression of the curves could be found. Conclusions: The prevalence of spinal deformity in patients with familial dysautonomia who had lived for at least twenty years was found to be 83 percent. By the age of ten years, 52 percent of the patients had scoliosis and 21 percent had kyphosis with or without scoliosis. Bracing was found to be of limited effectiveness as a definitive treatment for spinal deformity. The curve progressed despite bracing in fifty-eight (89 percent) of sixty-five patients.