title: Prevalence of vertebral fractures by semiautomated morphometry in patients with ankylosing spondylitis.
abstract: OBJECTIVE
  Ankylosing spondylitis (AS) is a chronic inflammatory disease mainly affecting the axial skeleton and characterized by ossification of the spinal disc, joints, and ligaments leading to progressive ankylosis. Vertebral osteoporosis is a recognized feature of AS. Studies have confirmed a moderate to high prevalence of vertebral fractures with extremely varying ranges in patients with AS. Our objective was to estimate the prevalence of vertebral fractures in a representative Spanish population of patients with AS using a validated semiquantitative method, MorphoXpress(®).
  
  
  METHODS
  Patients were randomly selected from the 10 initial participating centers of the Spanish National Registry of Spondyloarthropathies (REGISPONSER) by consecutive sampling. All patients fulfilled the New York modified criteria for AS and had a baseline thoracolumbar radiograph. A prevalent vertebral fracture was defined according to the Genant classification criteria.
  
  
  RESULTS
  The estimated prevalence of vertebral fractures was 32.4% (95% CI 25.5%-39.3%). The majority of fractures were localized in the thoracic segment (n = 100; 82.%) and were mild (n = 79; 64.8%). In logistic regression analysis, age (odds ratio per year 1.05, 95% CI 1.03-1.08, p < 0.001), disease duration (OR per year 1.03, 95% CI 1.01-1.06, p = 0.011), Bath Ankylosing Spondylitis Functional Index score (OR per score 1.16, 95% CI 1.03-1.30, p = 0.015), Bath Ankylosing Spondylitis Radiographic Index-TS (OR per score 1.25, 95% CI 1.12-1.39, p < 0.001), and wall-occiput distance (OR per cm 1.15, 95% CI 1.08-1.23, p < 0.001) were all associated with prevalent fracture.
  
  
  CONCLUSIONS
  Semiquantitative methods are needed to improve the diagnosis of vertebral fractures in AS in order to start early treatment and to avoid complications arising from osteoporosis.
authors.affiliation: Department of Rheumatology, Hospital Santa Maria, Lleida, c/Alcalde Rovira Roure 44, Lleida, Spain. nmontala@gmail.com
authors.forename: Nuria
authors.initials: N
authors.lastname: Montala
authors.forename: Xavier
authors.initials: X
authors.lastname: Juanola
authors.forename: Eduardo
authors.initials: E
authors.lastname: Collantes
authors.forename: Elisa
authors.initials: E
authors.lastname: Muñoz-Gomariz
authors.forename: Carlos
authors.initials: C
authors.lastname: Gonzalez
authors.forename: Jordi
authors.initials: J
authors.lastname: Gratacos
authors.forename: Pedro
authors.initials: P
authors.lastname: Zarco
authors.forename: Jose Luis
authors.initials: JL
authors.lastname: Fernandez Sueiro
authors.forename: Juan
authors.initials: J
authors.lastname: Mulero
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Torre-Alonso
authors.forename: Enrique
authors.initials: E
authors.lastname: Batlle
authors.forename: Loreto
authors.initials: L
authors.lastname: Carmona
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D011897:Random Allocation; D012042:Registries; D013030:Spain / Q000453:epidemiology; D016103:Spinal Fractures / Q000000981:diagnostic imaging / Q000453:epidemiology*; D013167:Spondylitis, Ankylosing / Q000453:epidemiology*