title: Are spinal or paraspinal anatomic markers helpful for vertebral numbering and diagnosing lumbosacral transitional vertebrae?
abstract: OBJECTIVE
  To evaluate the value of spinal and paraspinal anatomic markers in both the diagnosis of lumbosacral transitional vertebrae (LSTVs) and identification of vertebral levels on lumbar MRI.
  
  
  METHODS
  Lumbar MRI from 1049 adult patients were studied. By comparing with the whole-spine localizer, the diagnostic errors in numbering vertebral segments on lumbar MRI were evaluated. The morphology of S1-2 disc, L5 and S1 body, and lumbar spinous processes (SPs) were evaluated by using sagittal MRI. The positions of right renal artery (RRA), superior mesenteric artery, aortic bifurcation (AB) and conus medullaris (CM) were described.
  
  
  RESULTS
  The diagnostic error for evaluation of vertebral segmentation on lumbar MRI alone was 14.1%. In lumbarization, all patients revealed a well-formed S1-2 disc with squared S1 body. A rhombus-shaped L5 body in sacralization and a rectangular-shaped S1 body in lumbarization were found. The L3 had the longest SP. The most common sites of spinal and paraspinal structures were: RRA at L1 body (53.6%) and L1-2 disc (34.1%), superior mesenteric artery at L1 body (55.1%) and T12-L1 disc (31.6%), and AB at L4 body (71.1%). CM had variable locations, changing from the T12-L1 disc to L2 body. They were located at higher sacralization and lower lumbarization.
  
  
  CONCLUSIONS
  The spinal morphologic features and locations of the spinal and paraspinal structures on lumbar MRI are not completely reliable for the diagnosis of LSTVs and identification on the vertebral levels.
authors.affiliation: Department of Radiology, Gazi University School of Medicine, Ankara 06510, Turkey.
authors.forename: Nil
authors.initials: N
authors.lastname: Tokgoz
authors.affiliation: Department of Radiology, Gazi University School of Medicine, Ankara 06510, Turkey.
authors.forename: Murat
authors.initials: M
authors.lastname: Ucar
authors.affiliation: Department of Radiology, Gazi University School of Medicine, Ankara 06510, Turkey.
authors.forename: Aylin Billur
authors.initials: AB
authors.lastname: Erdogan
authors.affiliation: Department of Radiology, Gazi University School of Medicine, Ankara 06510, Turkey.
authors.forename: Koray
authors.initials: K
authors.lastname: Kilic
authors.affiliation: Department of Radiology, Gazi University School of Medicine, Ankara 06510, Turkey.
authors.forename: Cahide
authors.initials: C
authors.lastname: Ozcan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D059925:Anatomic Landmarks / Q000033:anatomy & histology*; D001012:Aorta, Abdominal / Q000033:anatomy & histology; D003951:Diagnostic Errors; D005260:Female; D006801:Humans; D007403:Intervertebral Disc / Q000033:anatomy & histology; D008159:Lumbar Vertebrae / Q000033:anatomy & histology*; D008161:Lumbosacral Region; D008279:Magnetic Resonance Imaging; D008297:Male; D017538:Mesenteric Artery, Superior / Q000033:anatomy & histology; D008875:Middle Aged; D012077:Renal Artery / Q000033:anatomy & histology; D015203:Reproducibility of Results; D012447:Sacrum / Q000033:anatomy & histology*; D013116:Spinal Cord / Q000033:anatomy & histology; D013131:Spine; D055815:Young Adult
keywords: Lumbosacral vertebrae; MRI; Spine; Transitional vertebrae