MEASUREMENTS OF THE NORMAL LUMBAR SPINAL-CANAL BY COMPUTED-TOMOGRAPHY - SEGMENTAL STUDY OF L3-L4 AND L4-L5 RELATED TO THE HEIGHT OF THE SUBJECT

Computed tomography measurements of the main diameters and cross section areas of the lumbar vertebral canal and the lower end of the dural sac at the L3-L4 and L4-L5 levels were made in 34 young male adults who were free of symptoms. This study shows a statistically significant correlation between the height of the subject and the cross sectional area of the canal and the dural sac, and the interpedicular diameter. The determination of regression coefficients enabled an estimate to be made of the mean values of these parameters in relation to height, the actual values having a normal distribution around these means. This study suggest that the areas, when narrowing is suspected, should be interpreted as a function of the height of the subject. © 1990 Springer-Verlag.