title: MRI of the alar and transverse ligaments in whiplash-associated disorders (WAD) grades 1-2: high-signal changes by age, gender, event and time since trauma.
abstract: BACKGROUND
  This study describes the prevalence of high-signal changes at magnetic resonance imaging (MRI) of the alar and transverse ligaments in whiplash-associated disorders (WAD) grades 1-2 in relation to age, gender, spinal degeneration, type of trauma event and time since trauma.
  
  
  METHODS
  In 1,266 consecutive WAD1-2 patients (779 women, 487 men; mean age 42 years) referred from clinicians, high-signal changes in the alar and transverse ligaments at high-resolution proton-weighted MRI were prospectively graded 0-3 based on a previously reported, reliable grading system. Type of event according to The International Statistical Classification of Diseases and Related Health Problems and time of trauma were obtained from referral letters.
  
  
  RESULTS
  MRI showed grades 2-3 alar ligament changes in 449 (35.5%; 95% confidence interval (CI), 32.8 to 38.1%) and grades 2-3 transverse ligament changes in 311 (24.6%; 95% CI, 22.2% to 26.9%) of the 1,266 patients. Grades 2-3 changes were more common in men than women, odds ratio 1.9 (95% CI, 1.5 to 2.5) for alar and 1.5 (95% CI, 1.1 to 2.0) for transverse ligament changes. High-signal changes were not related to age, spinal degeneration, type of trauma event or time since trauma (median 5 years). Unilateral changes were more often left- than right-sided.
  
  
  CONCLUSIONS
  High-signal changes of the alar and transverse ligaments are common in WAD1-2 and unlikely to represent age-dependent degeneration. Their male and left-side preponderance cannot be explained by variation in ligament stretching or image artefacts. Further studies are needed to clarify whether such changes are caused by trauma.
authors.affiliation: Department of Radiology, Haukeland University Hospital, Bergen, Norway. nils.vetti@helse-bergen.no
authors.forename: Nils
authors.initials: N
authors.lastname: Vetti
authors.forename: Jostein
authors.initials: J
authors.lastname: Kråkenes
authors.forename: Geir Egil
authors.initials: GE
authors.lastname: Eide
authors.forename: Jarle
authors.initials: J
authors.lastname: Rørvik
authors.forename: Nils Erik
authors.initials: NE
authors.lastname: Gilhus
authors.forename: Ansgar
authors.initials: A
authors.lastname: Espeland
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D002648:Child; D015897:Comorbidity; D005260:Female; D006801:Humans; D015994:Incidence; D008022:Ligaments / Q000293:injuries* / Q000473:pathology*; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D017678:Sex Distribution; D013997:Time Factors; D014911:Whiplash Injuries / Q000175:diagnosis* / Q000453:epidemiology*; D055815:Young Adult