[Quantitative evaluation, indications and value of computer tomography of the lumbar spine].

Beside demonstrating morphological changes, CT enables one to make quantitative measurements of the spinal canal (sagittal diameter, transverse diameter, area of the spinal canal, width of the lateral recess and symmetry of the articular joints). A reduction of the transverse diameter of the spinal canal or asymmetry of the articular joints is associated with an increased and earlier incidence of back pain. In addition, patients with asymmetrical vertebral joints showed more frequent and earlier development of disc prolapse.