title: Missed cervical disc bulges diagnosed with kinematic magnetic resonance imaging.
abstract: OBJECTIVE
  To determine if adding flexion and extension MRI studies to the traditional neutral views would be beneficial in the diagnosis of cervical disc bulges.
  
  
  METHODS
  Five hundred patients underwent MRI in neutral, flexion and extension positions. The images were analyzed using computer software to objectively quantify the amount of disc bulge.
  
  
  RESULTS
  Compared to the neutral position, cervical disc bulges were significantly increased in the extension position (P < 0.05), but on flexion position, there was no significant difference (P > 0.05). For patients without or <3 mm of disc bulge in neutral, 2.97% demonstrated an increase in bulge to ≥3 mm bulge in flexion, and 16.41% demonstrated an increase to ≥3 mm bulge in extension. For patients in the neutral view that had a baseline disc bulge of 3-5 mm, 3.73% had increased bulges to ≥5 mm in flexion and 11.57% had increased bulges to ≥5 mm in extension.
  
  
  CONCLUSIONS
  A significant increase in the degree of cervical disc bulge was found by examining extension views when compared with neutral views alone. Kinematic MRI views provide valuable added information, especially in situations where symptomatic radiculopathy is present without any abnormalities demonstrated on traditional neutral MRI.
authors.affiliation: Department of Orthopaedic Surgery, Renji Hospital Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Lifeng
authors.initials: L
authors.lastname: Lao
authors.forename: Michael D
authors.initials: MD
authors.lastname: Daubs
authors.forename: Trevor P
authors.initials: TP
authors.lastname: Scott
authors.forename: Kevin H
authors.initials: KH
authors.lastname: Phan
authors.forename: Jeffrey C
authors.initials: JC
authors.lastname: Wang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001696:Biomechanical Phenomena / Q000502:physiology; D002574:Cervical Vertebrae / Q000473:pathology*; D005260:Female; D006801:Humans; D007403:Intervertebral Disc / Q000473:pathology*; D007405:Intervertebral Disc Displacement / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging / Q000379:methods / Q000592:standards*; D008297:Male; D008875:Middle Aged; D016059:Range of Motion, Articular / Q000502:physiology; D055815:Young Adult