[Imaging in sciatica].

Sciatica being a benign disease its outcome is usually favourable, and paraclinical examinations should hold a modest role in its exploration, notably in the first painful episode. In reality, for multiple social, occupational and economic reasons imaging often intervenes at a very early stage of the condition. The role of standard radiography is to exclude non-discal diseases, and it should not need to be repeated in young adults. Computed tomography should be used only after a well-conducted treatment of six to eight weeks duration to demonstrate the responsible discal herniation and its morphological features in order to guide the therapeutic approach. Radiculography should no longer be performed as a first-line examination, but in about one out of ten cases it may be interesting to confirm an uncertain nerve root compression and, above all, to visualize in a standing up patient a container-contained maladjustment such as, for example, a vertebral canal stenosis. Magnetic resonance imaging, a rational, accurate and non-invasive method, unfortunately cannot be used as first-line examination due to its reduced accessibility in France.