The lumbar spinal canal in children. Part I: The sagittal diameter.

The sagittal diameter of the lumbar spinal canal has been measured on the radiographs of 100 children in age groups from three to fourteen years, both ages included. Corrections have been made for the factors of magnification, leading to the conclusion that the diameter does not vary significantly in the different age groups. The values correspond well to those given in previous anatomical investigations based upon adult skeletal material. The belief that the sagittal diameter increases in childhood appears to be due to disregard of the radiological enlargement. An hour-glass like shape of the lumbar spinal canal with narrowing at the third and fourth lumbar levels is present already from the age of 3.