title: Disc degeneration and cervical instability. Correlation of magnetic resonance imaging with radiography.
abstract: METHODS
  An imaging study was designed to evaluate disc degeneration and segmental instability in the cervical spine.
  
  
  OBJECTIVE
  To compare the magnetic resonance imaging assessment of disc degeneration with the conventional plain radiographic evaluation of cervical segmental instability.
  
  
  BACKGROUND
  No studies have been conducted to investigate the association of disc degeneration with cervical instability.
  
  
  METHODS
  Two hundred sixty consecutive patients with suspected cervical spine disorders were analyzed for horizontal and angular displacements on lateral flexion and extension radiographs and disc degeneration on T2-weighted magnetic resonance images of the cervical vertebrae.
  
  
  RESULTS
  In all intervertebral levels, the grade of disc degeneration increased significantly (P < 0.01) with age. Cervical instability was identified in 151 segments (14.5%) and correlated with Grade 1 and Grade 2 degeneration in the intervertebral discs (P < 0.01).
  
  
  CONCLUSIONS
  Cervical segmental instability may indicate early degeneration of intervertebral disc in the cervical vertebrae.
authors.affiliation: Department of Orthopaedic Surgery, Changzheng Hospital, Shanghai, China.
authors.forename: L
authors.initials: L
authors.lastname: Dai
mesh_terms: D000328:Adult; D000368:Aged; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging* / Q000473:pathology*; D005260:Female; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000175:diagnosis*; D007593:Joint Instability / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011859:Radiography