Normal Values of the Radiological Interpedunculate and Sagittal Diameter of Each Lumbar Vertebra in Normal Adults.

Lee, Sang Bong; Lee, Young Woo

Original Article

Journal of Korean Neurosurgical Society 1978;7(2): 275-284.

Department of Neurosurgery, Busan National University School of Medicine, Busan, Korea.

ABSTRACT

The significance of spinal canal size as determined by radiographic measurement was first appreciated in 1934 when Elsberg and Dyke published normal standards for maximum adult interpedunculate distances and demonstrated their application in the diagnosis of intraspinal tumor. The early works concerning the large spinal canal stimulated interest in the small canal. Generally with greater initial size of the canal, there is more space around the spinal cord and more encroachment can be tolerated without cord compression. Accordingly, the individual with development stenosis of the spinal canal is more susceptible to cord damage from spondylosis than the one with a canal of more generous proportions. One type of canal stenosis caused by hypertrophy of lamina and articular process can be detected by a dorsoventral measurement of intervertebral foramina, as advocated by Epstsin et al. In these subjects, the mid-sagittal diameter of spinal canal may be normal. In another type of stenosis dorsoventral measurement of intervertebral foramina is normal and the midsagittal diameter of the canal is diminished. Accordingly, when assessing a lumbar canal for stenosis, one should check the size of intervertebral foramina as well as the midsagittal diameter. Cases illustrating both types of stenosis are presented. Though normal sagittal and interpedunculate diameters of the lumbar canal in foreign peoples are published, we have yet not to encounter the Korean normal data. The purpose of this study was to establish the range of normal values of lumbar spinal canal midsagittal and interpedunculate diameter in the interest of facilitating clinical investigation of lumbar canal stenosis in Koreans. The authors undertook a radiographic measurement study of midsagittal and interpedunculate diameter of lumbar canal in Korean adults. The results were the followings: 1) The interpedunculate diameter from L1 to L5 in male were 23.97+/-1.38(mean+/-S.D.) mm, 24.80+/-1.44 mm, 25.95+/-1.57 mm, 27.46+/-1.75 mm and 30.27+/-1.83 mm respectively, and in female 22.12+/-1.21 mm, 23.01+/-1.34 mm, 24.41+/-1.60 mm, 25.90+/-1.75 mm and 29.02+/-1.32 mm respectively. In male and female combined those were 23.60+/-1.52 mm, 24.44+/-1.61 mm, 25.64+/-1.71 mm, 27.15+/-1.89 mm and 30.02+/-1.80 mm respectively. 2) The midsagittal diameter from L1 to L5 in male were 21.10+/-0.91mm, 20.9+/-1.04 mm, 20.82+/-0.87 mm, 20.64+/-1.18 mm and 20.44+/-1.03 mm respectively, and in female 20.80+/-0.88 mm, 20.90+/-0.61 mm, 21.08+/-0.91 mm, 20.21+/-0.65 mm and 19.50+/-0.42 mm respectively. In male and female combined those were 21.04+/-0.91 mm, 20.91+/-0.97 mm, 20.87+/-0.96 mm, 20.56+/-1.11 mm and 20.26+/-1.01 mm respectively. In general the diameter in male were larger than in female and the diameters were smaller in the lower lumbar regions than in the upper region. 3) Compared with the measurements of Hinck(USA) and Nagoshima(Japan). The IPD measurements in the present study were similar pattern with mild long distance of upper region and sagittal measurements were similar distance in upper region but lower region were shortest.