The Radiological Diagnosis of Herniated Lumbar Disks

To the Editor.— The March 2 STATE OF THE ART article1accurately compares the two conventional modalities, myelography and computed tomographic (CT) scanning. The radiological imaging of disk herniations would be so much more useful if radiologists and clinicians would combine their expertise to identify those herniations that are responsible for the patients' symptoms, ie, the offending disk. Too often today, with improved imaging techniques, multiple-level herniations are identified. This encourages needless disk explorations, injections, or excisions, and compromises what would otherwise be an excellent result. Incorporating dynamic studies, such as lateral bending and flexion-extension views performed in a standing position, enhances the myelogram in several ways. Lateral bending at a specific disk space will often be limited and cause symptoms in one direction or the other, depending on the relationship of the herniation to the nerve root. In addition, contained extreme lateral herniations will limit disk-space closure2