title: Ankylosing spondylitis is indigenous to Mesoamerica.
abstract: OBJECTIVE
  Paleopathology helps to define the origin and the migration of diseases. It has been established that genetic and environmental factors play a role in the pathogenesis of ankylosing spondylitis (AS). We investigated whether AS was present in Mesoamerica before contact with the European civilization.
  
  
  METHODS
  We studied the collection of Mesoamerican human skeletal remains preserved at the National Museum of Anthropology of Mexico, searching for features of AS.
  
  
  RESULTS
  We found one incomplete specimen of a man of the Postclassic period (900-1521 AD). It showed fusion of the vertebral column from T8 to L5 due to ankylosis of the apophyseal joints and of the spinal processes. The pelvis was not preserved. Radiographs demonstrated ossification of both supraspinous and interspinous ligaments.
  
  
  CONCLUSIONS
  Our findings suggest AS was present in Mesoamerica before the arrival of Europeans.
authors.affiliation: Instituto Nacional de Cardiología Ignacio Chávez, Mexico City, Mexico.
authors.forename: M
authors.initials: M
authors.lastname: Martínez-Lavín
authors.forename: J
authors.initials: J
authors.lastname: Mansilla
authors.forename: C
authors.initials: C
authors.lastname: Pineda
authors.forename: C
authors.initials: C
authors.lastname: Pijoán
mesh_terms: D049690:History, Ancient; D006801:Humans; D008297:Male; D008800:Mexico; D010164:Paleopathology; D011859:Radiography; D011884:Radius / Q000473:pathology; D012272:Ribs / Q000473:pathology; D013131:Spine / Q000000981:diagnostic imaging / Q000473:pathology; D013167:Spondylitis, Ankylosing / Q000266:history* / Q000473:pathology