Accurate delineation of the various types of lumbar disc herniation is vital for their proper management. We retrospectively reviewed 61 cases of ruptured intervertebral lumbar disc which were confirmed intraoperatively, and compared with the randomized selected contained discs of 61 cases to find out clinical and radiological characteristics of ruptured disc. The ruptured disc could be diag- nosed if the patients had following signs or findings. (1) more specific neurologic signs such as Lasegue sign, Peyton sign, muscle weakness, and hypoesthesia. (2) findings of total block and irregular marginal defect of contrast media in myelography. (3) more than 0.20 hernia index: 95% of sensitivity and 89.9% of specificity. (4) findings of torn PLL on sagittal view of proton density and T2-weighted image in extruded patients. (5) findings of high-signal-intensity extradural defects on T2-weighted image and round rim enhancement with Gd-DTPA on Tl-weighted image in sequestered patients.