The use of nuclear magnetic resonance in the diagnosis of lateral canal entrapment.

The use of nuclear magnetic resonance (NMR) in the diagnosis of radicular pain due to lateral canal stenosis in 21 patients is reported. NMR was able to distinguish normal intervertebral discs from degenerate discs, and NMR evidence of reduction of epidural fat was more reliable than radiculography in identifying lateral root entrapment. NMR is an important advance in the investigation of lumbar radiculopathies.