title: Facet joint signal change on MRI at levels of acute/subacute lumbar compression fractures.
abstract: OBJECTIVE
  The prevalence of facet joint signal change in acute/subacute lumbar vertebral body compression fractures is unknown. We hypothesized that facet joint signal change on MR imaging is more common in facet joints associated with an acute/subacute lumbar compression fracture than those associated with normal vertebral bodies or ones that have a chronic compression fracture.
  
  
  METHODS
  Three neuroradiologists and a neuroradiology fellow retrospectively graded facet joint inflammatory change on MR imaging in 900 facet joints in 75 patients with at least 1 painful osteoporotic lumbar compression fracture. Facet joint signal change was assessed on T2-weighted images with chemical fat-saturation, STIR images, and/or gadolinium-enhanced T1-weighted images with chemical fat-saturation. Each facet joint from the T12/L1 to L5/S1 level was assessed individually. An overall facet joint signal-change score, which is a composite measure of the grade of signal change for all 4 facet joints associated with a given lumbar vertebral level, was devised, and statistical significance was assessed via Wilcoxon rank sum tests.
  
  
  RESULTS
  The overall facet joint signal-change scores were significantly higher at vertebral body levels affected by an acute/subacute compression fracture compared with control levels, which were associated with either normal bodies or chronic compression fractures.
  
  
  CONCLUSIONS
  Our findings suggest an association between facet joint signal change on MR imaging and acute/subacute lumbar vertebral body compression fractures.
authors: Division of Neuroradiology, Department of Radiology, Mayo Clinic College of Graduate Medical Education, Rochester, MN 55905, USA. Lehman.vance@mayo.edu
authors: V T
authors: VT
authors: Lehman
authors: C P
authors: CP
authors: Wood
authors: C H
authors: CH
authors: Hunt
authors: R E
authors: RE
authors: Carter
authors: J B
authors: JB
authors: Allred
authors: F E
authors: FE
authors: Diehn
authors: J M
authors: JM
authors: Morris
authors: J T
authors: JT
authors: Wald
authors: K R
authors: KR
authors: Thielen
mesh_terms: D000208:Acute Disease; D000368:Aged; D002908:Chronic Disease; D003287:Contrast Media; D005260:Female; D050815:Fractures, Compression / Q000175:diagnosis* / Q000473:pathology; D005682:Gadolinium; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008159:Lumbar Vertebrae / Q000293:injuries* / Q000473:pathology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D010024:Osteoporosis / Q000150:complications; D012189:Retrospective Studies; D013122:Spinal Diseases / Q000150:complications; D016103:Spinal Fractures / Q000175:diagnosis* / Q000473:pathology; D013166:Spondylitis / Q000175:diagnosis / Q000473:pathology; D021801:Zygapophyseal Joint / Q000473:pathology*
chemical_list: D003287:Contrast Media; D005682:Gadolinium