Analysis of discrepancy between neurologic findings and CT findings in 60 patients with herniated nucleus pulposus

The herniated nucleus pulposus (HNP) is a major cause of low back pain and sciatica. High resolution computed tomography is the most accurate diagnostic tool to define a HNP, because it provides a complete in vivo analysis of bony framework of lumbar spine as well as the supporting soft tissue structures and neural elements. But the discrepancy between neurologic findings and CT findings is often confusing. From May 1983 to August 1986, sixty patients with HNP who had both CT and surgical intervention at Pusan National University Hospital were analyzed. The feasibility of the neurologic examination on HNP and the effect of HNP on nerve root were evaluated on the basis of CT findings. The results were as follows : 1. Thirty-four cases (56.7%) of clinical impression were matched to CT findings in determining level of HNP and affected nerve root. 2. In evaluation of affected level, there was high trend to cause discrepancy between neurologic findings and CT findings in multiple disc involvement than in single involvement. 3. There was no correlation between degree of nerve root compression determined by CT and pattern of neurologic signs (motor weakness, sensory deficit, and reflex change)