title: The efficacy of the modified classification system of soft tissue injury in extension injury of the lower cervical spine.
abstract: METHODS
  To classify comprehensively the severity of soft tissue injury for extension injuries of the lower cervical spine by magnetic resonance imaging (MRI).
  
  
  OBJECTIVE
  To investigate severity of extension injuries using a modified classification system for soft tissue injury by MRI, and to determine the possibility of predicting cord injury by determining the severity of soft tissue injury.
  
  
  BACKGROUND
  It is difficult to diagnose extension injuries by plain radiography and computed tomography. MRI is considered to be the best method of diagnosing soft tissue injuries. The authors examined whether an MRI based diagnostic standard could be devised for extension injuries of the cervical spine.
  
  
  METHODS
  MRI was performed before surgery in 81 patients that had experienced a distractive-extension injury during the past 5 years. Severities of soft tissue injury were subdivided into 5 stages. The retropharyngeal space and the retrotracheal space were measured, and their correlations with the severity of soft tissue injury were examined, as was the relation between canal stenosis and cord injury.
  
  
  RESULTS
  Cord injury developed in injuries greater than Grade III (according to our devised system) accompanied by posterior longitudinal ligament rupture (P < 0.01). As the severity of soft tissue injury increased, the cord signal change increased (P < 0.01), the retropharyngeal space and the retrotracheal space increased, and swelling severity in each stage were statistically significant (P < 0.01). In canal stenosis patients, soft tissue damage and cord injury were not found to be associated (P = 0.45).
  
  
  CONCLUSIONS
  In cases of distractive-extension injury, levels of soft tissue injury were determined accurately by MRI. Moreover, the severity of soft tissue injury was found to be closely associated with the development of cord injury.
authors.affiliation: Department of Orthopedic Surgery, Chonbuk National University School of Medicine, Chonbuk National University Hospital, Jeonju, Korea.
authors.forename: Kyung-Jin
authors.initials: KJ
authors.lastname: Song
authors.forename: Gyu-Hyung
authors.initials: GH
authors.lastname: Kim
authors.forename: Kwang-Bok
authors.initials: KB
authors.lastname: Lee
mesh_terms: D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D002574:Cervical Vertebrae / Q000293:injuries*; D016009:Chi-Square Distribution; D005260:Female; D006801:Humans; D015601:Injury Severity Score; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D017695:Soft Tissue Injuries / Q000145:classification* / Q000175:diagnosis*; D013119:Spinal Cord Injuries / Q000145:classification* / Q000175:diagnosis*