Transverse diameter of the lumbar spinal canal in normal adult Saudis.

Pathological changes in the diameters of the lumbar spinal canal may be associated with low back pain. The assessment of the size of the canal is therefore an important diagnostic procedure. Evidence suggests that there are ethnic differences in the dimensions of the canal. A radiogrammetric study was therefore undertaken to establish norms of the transverse diameter for the Saudi population. The results show that the transverse diameter of the canal in Saudis differ from that of other populations, but the shape is similar to those of earlier reports. Intersegmental differences which are useful for the detection of isolated segmental anomalies were also calculated. The significance of the findings is discussed.