Ultrasonic level diagnosis of lumbar disc herniation.

Although the use of diagnostic ultrasound to measure the spinal canal has been proposed, the value of ultrasound for lumbar disc herniation has not been yet fully assessed. The purpose of this investigation was to evaluate the effectiveness of ultrasound in the level diagnosis of herniated nucleus pulposus. Prospective ultrasound examinations were performed on 80 consecutive patients with clinically suspected lumbar disc herniation. In 41 discs of those 40 patients with surgically confirmed lumbar disc herniation, there were 32 discs (78%) with true-positive ultrasound diagnoses, 37 discs (90%) with true-positive myelographic diagnoses, and 20 patients (50%) with true-positive neurologic diagnoses. Conversely, ultrasound diagnoses showed positive echogram in 24 (60%) of 40 nonoperative patients. These results suggest that ultrasound is of value as an aid for diagnosing the level of lumbar disc herniation.