title: The Torg--Pavlov ratio in cervical spondylotic myelopathy: a comparative study between patients with cervical spondylotic myelopathy and a nonspondylotic, nonmyelopathic population.
abstract: METHODS
  A radiologic study to compare the Torg--Pavlov ratios between patients with cervical spondylotic myelopathy and a nonspondylotic, nonmyelopathic population.
  
  
  OBJECTIVE
  To determine and compare the Torg--Pavlov ratios between the two groups of patients.
  
  
  BACKGROUND
  Patients with congenital cervical spinal canal stenosis are more likely to develop cervical spondylotic myelopathy. The Torg--Pavlov ratio eliminates errors related to magnification, a problem with determination of spinal canal stenosis from direct measurements of plain cervical spine radiographs. There has only been one other study that directly compares the Torg--Pavlov ratio between patients with cervical spondylotic myelopathy and a normal control population.
  
  
  METHODS
  The preoperative plain lateral cervical spine radiographs of 28 patients with cervical spondylotic myelopathy requiring surgical decompression were compared with radiographs of 88 nonspondylotic, nonmyelopathic patients. The Torg--Pavlov ratio was computed for each level from C3 to C7.
  
  
  RESULTS
  The study showed that the Torg--Pavlov ratio is significantly smaller (P < 0.001) in myelopathic patients (mean 0.72 +/- 0.08) compared with the control patients (mean 0.95 +/- 0.14). This was so when individual levels and the mean values were compared. Age was also found to be a significant factor (P = 0.002), although lesser in magnitude when compared with the Torg--Pavlov ratio (P = 0.0001).
  
  
  CONCLUSIONS
  The Torg--Pavlov ratio is significantly lower in patients with cervical spondylotic myelopathy compared with a nonspondylotic, nonmyelopathic population. It could possibly be used to predict the likelihood of developing cervical spondylotic myelopathy.
authors.affiliation: Department of Orthopedic Surgery, Singapore General Hospital, Singapore.
authors.forename: W M
authors.initials: WM
authors.lastname: Yue
authors.forename: S B
authors.initials: SB
authors.lastname: Tan
authors.forename: M H
authors.initials: MH
authors.lastname: Tan
authors.forename: D C
authors.initials: DC
authors.lastname: Koh
authors.forename: C T
authors.initials: CT
authors.lastname: Tan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D011859:Radiography; D012016:Reference Values; D013115:Spinal Canal / Q000000981:diagnostic imaging / Q000473:pathology*; D013117:Spinal Cord Compression / Q000000981:diagnostic imaging / Q000209:etiology / Q000473:pathology*; D013128:Spinal Osteophytosis / Q000150:complications / Q000000981:diagnostic imaging / Q000473:pathology*