Imaging and electrophysiological evidence of
nerve-root compression corroborates structural
disk or spine disease as the proximate cause of
sciatica, but testing is not necessary in a typical
case until intervention is required. Radiographs
of the lumbar spine provide limited information,
but they may show reduction in the height of an intervertebral space, spondylolisthesis, osteomyelitis,
or tumor infiltration of a vertebral body.
The nature and location of disk rupture and spinal
lesions, such as osteoarthritic disease and
spondylolisthesis, lateral recess stenosis, and synovial
cysts of the facet joint, can be accurately
seen on magnetic resonance imaging (MRI) without
the administration of gadolinium