Predicting lumbar central canal stenosis - a magnetic resonance imaging study.

Abstract

Low back pain is a common complaint among adults, worldwide. Lumbar canal stenosis is frequently diagnosed as a cause for low back pain. In this study we evaluate morphometric measures using MRI sections to predict the occurrence of lumbar central canal stenosis. One hundred and fifty four lumbar spinal MRI sagital and axial section images, 77 males and females each were evaluated from the Department of Radiology, Kasturba Medical College, Mangalore, Manipal University. The study design was a prospective study. Various measurements were taken and two constant ratios were calculated. The Canal Body Ratio and the Ratio between the area of the dural sac and the vertebral body was evaluated. Unpaired t-test analysis was conducted using SPSS software. A canal body ratio less than 0.6 from L1 to L3 levels and less than 0.5 at L4 and L5 levels were found. The ratio between area of dural sac and vertebral body was found to be a constant at 0.2 at all levels. It was found that maximum central canal stenosis occurred at the L5 lumbar vertebral level in 15.6% males and 13% females. This was followed by stenosis at the L4 and L3 lumbar vertebral levels with 5.1% males having stenosis at both levels and 3.9% and 5.1% females in L4 and L3 lumbar levels respectively. These morphometrical findings of the lumbar vertebrae could be of use in evaluating the possible cases of lumbar canal stenosis.