title: Clinical correlation of a new practical MRI method for assessing cervical spinal canal compression.
abstract: OBJECTIVE
  The purpose of this study was to evaluate interobserver agreement and whether or not a new MRI grading system correlates with symptoms and neurologic signs for assessing spinal canal compression.
  
  
  METHODS
  One hundred patients (52 men and 48 women; mean age, 50 years) underwent MRI of the cervical spine at our institution and were evaluated by two musculoskeletal radiologists. The presence and grade of cervical canal stenosis at the maximal narrowing point was assessed according to the new grading system suggested by Kang et al. (Kang system). The results correlated with the clinical manifestations and neurologic examination. Statistical analysis was performed using kappa statistics, categoric regression analysis, and nonparametric correlation analysis (Spearman correlation).
  
  
  RESULTS
  Interobserver agreement in the grading of spinal stenosis between the two readers was almost perfect (κ = 0.925). Most of the patients with grade 0 cervical canal stenosis showed no neurologic manifestation, and patients with grades 2 and 3 cervical canal stenosis had positive neurologic manifestations. The correlation coefficient (R) of reader 1 between MRI grade (0, 1, 2, and 3) and neurologic manifestations (positive or negative) was 0.846. The R of reader 2 was 0.808. In the younger age group (< 50 years old), the R of reader 1 was 0.834 and the R of reader 2 was 0.745. In the older age group (≥ 50 years old), the R of reader 1 was 0.839 and the R of reader 2 was 0.839.
  
  
  CONCLUSIONS
  The interobserver agreement of the Kang system was almost perfect and was higher than in the study by Kang et al. Grade 0 cervical canal stenosis represents negative neurologic manifestations and grades 2 and 3 cervical canal stenosis represent positive neurologic manifestations. The Kang system and clinical manifestations are significantly correlated, especially in the older age group (≥ 50 years).
authors: Department of Radiology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors: Hee-Jin
authors: HJ
authors: Park
authors: Sam Soo
authors: SS
authors: Kim
authors: Eun-Chul
authors: EC
authors: Chung
authors: So-Yeon
authors: SY
authors: Lee
authors: Noh-Hyuck
authors: NH
authors: Park
authors: Myung-Ho
authors: MH
authors: Rho
authors: Sun-Hyung
authors: SH
authors: Choi
mesh_terms: D000328:Adult; D002574:Cervical Vertebrae; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013117:Spinal Cord Compression / Q000175:diagnosis*; D013130:Spinal Stenosis / Q000175:diagnosis*; D018709:Statistics, Nonparametric