Nonoperative management of herniated nucleus pulposus: patient selection by the extension sign. Long-term follow-up.

We have previously reported that the ability of patients with herniated nucleus pulposus (HNP) and radiculopathy to achieve full passive lumbar extension (negative extension sign) is a useful predictor of favorable response to conservative management. Of 154 patients with back pain and radiculopathy seen between 1979 and 1985, 73 were selected for conservative management based on this criterion. We also reviewed results of electromyography (EMG), computed tomography (CT), myelography, straight leg raise, crossed straight leg raise, deep tendon reflex, and dermatomal-sensory and motor deficits. Ninety-four percent of the subjects achieved full extension within 5 days of hospital admission. Although some patients who had full extension on admission subsequently underwent chemonucleolysis or surgery, none of those who could not extend initially and who later gained full lumbar extension required surgery. Of the 33 patients who were available for long-term follow-up, 94% were satisfied with the results, 82% were able to resume working, 73% required no analgesics, and 9% later required chemonucleolysis or surgery. Positive findings on admission EMG (5 of 7 patients), myelography (5 of 8 patients), or CT (9 of 11) did not preclude good results with conservative management. Female patients without complaint at follow-up (53%) outnumbered their male counterparts (25%). Patients (19 of 33) whose extension sign was initially positive on admission and became negative within 5 days of hospitalization (average, 1.6 days) had better outcomes with 95% satisfied, 90% without job changes, 74% not requiring analgesia, and none requiring surgery. At long-term follow-up, the extension sign effectively predicted a favorable response to nonoperative therapy of HNP in 91% of cases.(ABSTRACT TRUNCATED AT 250 WORDS)