title: The association of syndesmophytes with vertebral bone mineral density in patients with ankylosing spondylitis.
abstract: OBJECTIVE
  To determine bone mineral density (BMD) using the posteroanterior L2-L4 (PA) and lateral L3 (LAT-L3) projections of dual energy x-ray absorptiometry (DEXA) in patients with ankylosing spondylitis (AS), and to evaluate the relationship between BMD and the presence of syndesmophytes.
  
  
  METHODS
  Twenty men with AS were studied. BMD was measured by femoral neck DEXA, PA DEXA, and LAT-L3 DEXA scans. Radiographs of lumbar spine were evaluated to obtain a lumbar spine score (LSS) for the presence of syndesmophytes. Twenty-three age matched healthy men served as controls.
  
  
  RESULTS
  While there was no significant difference in BMD from PA DEXA results between AS patients and controls, BMD from the LAT-L3 DEXA was significantly reduced in AS patients (p = 0.009). LSS correlated significantly with BMD from PA DEXA (r = 0.55, p = 0.013), but not with BMD of LAT-L3 DEXA.
  
  
  CONCLUSIONS
  LAT-L3 DEXA was superior to PA DEXA in detecting a decrease of BMD in patients with AS. The presence of syndesmophytes had no distorting effect on BMD measured by LAT-L3 DEXA.
authors.affiliation: Division of Rheumatology, Faculty of Medicine, Akdeniz University, Antalya, Turkey. erdalgilgil@akdeniz.edu.tr
authors.forename: Erdal
authors.initials: E
authors.lastname: Gilgil
authors.forename: Cahit
authors.initials: C
authors.lastname: Kaçar
authors.forename: Tiraje
authors.initials: T
authors.lastname: Tuncer
authors.forename: Bülent
authors.initials: B
authors.lastname: Bütün
mesh_terms: D015502:Absorptiometry, Photon / Q000379:methods*; D000328:Adult; D015519:Bone Density; D002114:Calcinosis / Q000378:metabolism / Q000473:pathology*; D005272:Femur Neck / Q000000981:diagnostic imaging / Q000378:metabolism; D006801:Humans; D008023:Ligaments, Articular / Q000378:metabolism / Q000473:pathology*; D008159:Lumbar Vertebrae / Q000378:metabolism / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D013167:Spondylitis, Ankylosing / Q000378:metabolism / Q000473:pathology*