The level of CT section in the lumbosacral region may be correlated with routine AP views of the spine using a reference plane constructed according to the distance between the iliac crests. CT scans of the spine in 100 patients have been analyzed. The majority of these cases consisted of primary or secondary bone or soft-tissue tumors. CT examination was valuable to supplement plain films and/or myelograms in evaluation of the extent of pathology. It was also useful in the work-up of patients with malignant tumors whose other studies were equivocal.