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Lumber canal has been measured by various methods but none has been found very satisfactory. We have measured the canal to body ratio by finding out the area (rather than cross section) of the vertebral bodies and spinal canal as seen on epidurogram by planometer (a civil engineering instrument to find out area of irregular figures in the maps) in A.P. and lateral view. Twentytwo patients were studied, 17 of them had normal lumber canal, 3 had prolapsed intervertebral disc and 2 had lumber canal stenosis. The areas of the spinal canal in lumber region were measured in antero-posterior and lateral views at each vertebral level by planometer and their sums were compared to the sums of the corresponding areas of the vertebral bodies at the same level. Normal range of body to canal ratio was found to be 1:1.5 to 1:3.9 and was comparable with other Indian figures.