Index by author

Extra- and subligamentous lumbar disk herniations are treated differently. These authors utilized 10 criteria in an attempt to establish the exact location of disk herniations with respect to the posterior longitudinal ligament. Extraligamentous herniations showed: 1) spinal canal compromise of more than half its diameter, 2) internal signal difference in the disk, 3) ill-defined disk margins, 4) disruption of the continuous low-signal-intensity line covering the disk, and 5) presence of an internal dark line in the herniated disk. When combined these 5 yield sensitivity, specificity, accuracy, and an odds ratio of 77.3%, 74.5%, 76.1%, and 9.93, respectively.