title: Sequential damage assessment of the different components of the posterior ligamentous complex after magnetic resonance imaging interpretation: prospective study 74 traumatic fractures.
abstract: METHODS
  Prospective cohort study.
  
  
  OBJECTIVE
  To study whether there is a sequential pattern in the posterior ligamentous complex (PLC) rupture caused by deforming traumatic forces by analyzing magnetic resonance (MR) images in a consecutive prospective cohort of patients with traumatic vertebral fracture.
  
  
  BACKGROUND
  PLC plays an important role in vertebral stability. However, the sequence in which the different components of the PLC tear, in the face of traumatic forces, has not been yet described.
  
  
  METHODS
  Prospective study of 74 consecutive vertebral acute traumatic fractures analyzed using radiography and magnetic resonance imaging (MRI) (FS-T2-w/short-tau inversion-recovery [STIR] sequences). Fracture morphology was classified according to the AO classification. Integrity of each PLC component-facet capsules, interspinous ligament (ISL), supraspinous ligament (SSL), and ligamentum flavum (LF)-was assessed and classified as intact, edema, or disruption. ISL edema was further subdivided depending on the extension (>50%/<50%). We analyzed the association between MRI signal and the AO progressive scale of morphological damage.
  
  
  RESULTS
  AO type A1/A2 fractures associated with only facet distraction. A3 fractures showed additional ISL edema, usually less than 50%, with neither SSL nor LF disruption. Type B1 fractures associated with facet distraction, ISL edema or disruption, and low rate of SSL/LF disruptions; B2 fractures increased SS/LF disruption rates. Type C fractures associated with facet fracture or dislocation and ISL, SSL, or LF complete rupture. We found high association (P < 0.001) between AO progressive scale and MRI signal. MRI analysis showed that posterior distraction forces begin in the facets and extend throughout the ISL, starting at its posterosuperior margin (finally disinserting the SSL superiorly) and traveling diagonally toward anteroinferior border, finally tearing the LF.
  
  
  CONCLUSIONS
  MR images correlated with AO progressive scale of morphological damage, which showed a progressive orderly rupture sequence among the different PLC components as traumatic forces increased.
authors.affiliation: Spine Unit, Department of Orthopaedic Surgery, Hospital Universitario de Getafe, Madrid, Spain. javier.pizones@wanadoo.es
authors.forename: Javier
authors.initials: J
authors.lastname: Pizones
authors.forename: Enrique
authors.initials: E
authors.lastname: Izquierdo
authors.forename: Felisa
authors.initials: F
authors.lastname: Sánchez-Mariscal
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Zúñiga
authors.forename: Patricia
authors.initials: P
authors.lastname: Álvarez
authors.forename: Alejandro
authors.initials: A
authors.lastname: Gómez-Rice
mesh_terms: D000328:Adult; D004487:Edema / Q000175:diagnosis / Q000209:etiology; D005260:Female; D006801:Humans; D008022:Ligaments / Q000000981:diagnostic imaging* / Q000293:injuries; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011859:Radiography; D015203:Reproducibility of Results; D012421:Rupture / Q000175:diagnosis / Q000209:etiology; D012680:Sensitivity and Specificity; D016103:Spinal Fractures / Q000150:complications*; D013124:Spinal Injuries / Q000175:diagnosis* / Q000209:etiology