A clinically relevant MRI grading system for lumbar central canal stenosis.

Objective: To correlate lumbar spinal stenosis as graded on noncontrast magnetic resonance imaging (MRI) with clinical symptomatology.

Methods: Five grades were developed for lumbar central canal stenosis based on compression of the dural sac and cauda equina. We studied concordance in 112 patients between the grading system and the anteroposterior diameter of spinal canal, dural sac cross-sectional area, Oswestry disability index, and the pain visual analogue scale (VAS).

Results: Intra- and interobserver agreement was high. Although VAS was not significantly different between groups (P=.257), all other factors were significant (P≤.005).

Conclusions: The MRI grading system reliably predicted the degree of stenosis and associated disability.