title: Orientation of the facet joints in degenerative rotatory lumbar scoliosis: an MR study on 52 patients.
abstract: BACKGROUND
  Because of a degenerative component, degenerative rotatory scoliosis seems different from congenital and idiopathic subtypes of the disease. This study aims to examine the orientation of facet joints, as a known cause of degeneration, in patients with degenerative rotatory scoliosis.
  
  
  METHODS
  Lumbar magnetic resonance (MR) images and plain radiographs of 52 symptomatic patients (mean age, 50.17 years) with degenerative rotatory lumbar scoliosis (mean curve, 19.22 degrees) and 50 healthy individuals were reviewed. Facet joint angles in rotated segments and the minimum neural foramen width at all lumbar levels were measured by three observers and the average was recorded.
  
  
  RESULTS
  The maximum vertebral rotation was most frequent at L4-L5 (75 %), and the majority was of type I (84.6 %) according to the Nash-Moe classification. At all lumbar spinal levels the mean facet joint angles were significantly higher on the side of rotation (L2-L3, 57.92 degrees; L3-L4, 45.00 degrees; L4-L5, 43.88 degrees) compared to those on the contralateral side (L2-L3, 20.42 degrees; L3-L4, 15.48 degrees; L4-L5, 13.12 degrees) and in controls (L2-L3, 30.21 degrees; L3-L4, 40.81 degrees; L4-L5, 45.20 degrees) (p < 0.001 for all comparisons). The mean facet joint angle increased significantly from L4-L5 to L2-L3 in cases and reversely in controls. The mean minimum neural foramen width was 1.29 ± 0.85 mm on the side of rotation, 5.50 ± 1.09 mm on the contralateral side, and 6.78 ± 1.75 mm in controls (p < 0.001).
  
  
  CONCLUSIONS
  Substantial asymmetries and abnormal orientations in facet joints were documented in patients with degenerative rotatory lumbar scoliosis. Such asymmetries may adversely affect neural foramen width.
authors.affiliation: Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Masoud
authors.initials: M
authors.lastname: Poureisa
authors.affiliation: Department of Radiology, Zabol University of Medical Sciences, Zabol, Iran.
authors.forename: Razieh
authors.initials: R
authors.lastname: Behzadmehr
authors.affiliation: Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Mohammad Hossein
authors.initials: MH
authors.lastname: Daghighi
authors.affiliation: Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Leila
authors.initials: L
authors.lastname: Akhoondzadeh
authors.affiliation: Neurosciences Research Center, Tabriz University of Medical Sciences, Imam Reza Teaching Hospital, Golgasht Street, Tabriz, Iran. Medicorelax@yahoo.com.
authors.forename: Daniel Fadaei
authors.initials: DF
authors.lastname: Fouladi
mesh_terms: D000328:Adult; D015992:Body Mass Index; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D055959:Intervertebral Disc Degeneration / Q000473:pathology; D008161:Lumbosacral Region / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D012399:Rotation; D012600:Scoliosis / Q000473:pathology*; D021801:Zygapophyseal Joint / Q000473:pathology*
keywords: Asymmetry; Degenerative rotatory scoliosis; Facet joint; Neural foramen