title: [Disc degeneration and cervical instability].
abstract: OBJECTIVE
  To evaluate disc degeneration and segmental instability in the cervical spine by comparing the magnetic resonance imaging assessment of disc degeneration with conventional plain radiographic evaluation with cervical segmental 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 T(2)-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, Second Military Medical University, Shanghai 200003.
authors.forename: L
authors.initials: L
authors.lastname: Dai
mesh_terms: D000328:Adult; D000368:Aged; D002574:Cervical Vertebrae; D005260:Female; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000150:complications* / Q000175:diagnosis; D007593:Joint Instability / Q000175:diagnosis / Q000209:etiology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged