title: Apophysial joint degeneration, disc degeneration, and sagittal curve of the cervical spine. Can they be measured reliably on radiographs?
abstract: METHODS
  Interexaminer reliability study.
  
  
  OBJECTIVE
  To determine the reliability of grading apophysial joint and disc degenerative changes and the reliability of measuring sagittal curves on lateral cervical spine radiographs.
  
  
  BACKGROUND
  Several authors have proposed that the presented of degenerative changes and the absence of lordosis in the cervical spine are indicators of poor recovery from neck injuries caused by motor vehicle collisions. The validity of those conclusions is questionable because the reliability of the methods used in their studies to measure the presence of degenerative changes and the absence of lordosis has not been determined.
  
  
  METHODS
  Kellgren's classification system for apophysial joint and disc degeneration, as well as the pattern and magnitude of the sagittal curve on 30 lateral cervical spine radiographs were assessed independently by three examiners.
  
  
  RESULTS
  Moderate reliability was demonstrated for classifying apophysial joint degeneration with an intraclass correlation coefficient of 0.45 (95% confidence interval, 0.09-0.71). Classifying degenerative disc disease had substantial reliability, with an intraclass correlation coefficient of 0.71 (95% confidence interval, 0.23-0.88). Measuring the magnitude of the sagittal curve from C2 to C7 had excellent interexaminer agreement, with an intraclass correlation coefficient of 0.96 (95% confidence interval, 0.88-0.98) and an interexaminer error of 8.3 degrees.
  
  
  CONCLUSIONS
  The classification system for degenerative disc disease proposed by Kellgren et al and the method of measurement of sagittal curves from C2 to C7 demonstrated an acceptable level of reliability and can be used in outcomes research.
authors.affiliation: Division of Orthopaedics, University of Saskatchewan, Canada.
authors.forename: P
authors.initials: P
authors.lastname: Côté
authors.forename: J D
authors.initials: JD
authors.lastname: Cassidy
authors.forename: K
authors.initials: K
authors.lastname: Yong-Hing
authors.forename: J
authors.initials: J
authors.lastname: Sibley
authors.forename: J
authors.initials: J
authors.lastname: Loewy
mesh_terms: D000704:Analysis of Variance; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging* / Q000293:injuries*; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000000981:diagnostic imaging* / Q000453:epidemiology; D015588:Observer Variation; D011859:Radiography; D015203:Reproducibility of Results; D013128:Spinal Osteophytosis / Q000000981:diagnostic imaging* / Q000453:epidemiology; D014911:Whiplash Injuries / Q000000981:diagnostic imaging* / Q000453:epidemiology