In spite of numerous dinical and patho-anatomical studies made in the past, there are still different opinions concerning the mechanism of low back pain. The sciatic symptoms in degenerative lumbar disc disease may arise from the direct mechanical effect of pressure exerted by protruding disc material on nerve roots, and that such symptoms may therefore be relieved by surgical decompression of the nerve roots, has been widely accepted for nearly 40 years. There is, however, a good deal of evidence, both from operative and histological findings as well as from indirect sources, which suggests that inflammatory changes present in and around affected nerve roots may also be of importance in the production of sciatic symptoms in lumbar disc disease. The possibility that, at least in some cases, these inflammatory changes could contribute significantly or even predominantly to the production and persistence of sciatic symptoms, has stimulated many attempts to treat sciatica by means of local antiinflammatory measures in particular, corticosteroid injections. We have studied the effect of the injection of mixture triamcinolone and local anesthetic (1% xylocaine or 0.5% marcaine) comparing with the effect of usual conservative treatment of low back pain and sciatica. Of the 92 patients suffered from lumbago & sciatica, who were treated from 1979. 7 to 1981. 7 in Korea and Jae Il general hospital, 44 patients were treated with intermittent epidural block, 12 patients with continuous epidural block and 36 patients were treated only with usual conservative treatment. The results of clinical observation were as follows: 1. The causative disease were herniated nucleus pulposus in 60 patients (64%), lumbar sprain in 12 (13%), degenerative joint disease of spine in 11 (12%),… 2. The epidural block cases were divided into acute group (symptoms less than 3 months) and chronic group (symptoms longer than 3 months). The over all improvement of the acute group was 22 of 27(81%) and of the chronic group was 22 of 29(76%). The duration of symptoms didnt influenced significantly the effect of epidural block. 3. Therapeutic effect of epidural block was as follows; complete relief 22 of 56(39%), marked relief 13 of 56(23%), slight relief 9 of 56(16%), no improvement 12 of 56(22%). The over all improvement was resulted in 44 of 56(78%): intermittent epidural block 34 of 44(77%), continuous epidural block 10 of 12(83%). 4. Therapeutic effect of conservative treatment was as follows; complete relief 10 of 36(28%), marked relief 7 of 36(19%), slight relief 4 of 36(11%), no improvement 15 of 36(42%). The over all improvement of symptoms was resulted in 21 of 36(58%). 5. Follow up period of epidural block patients were 3 months in average, and persistent relief of symptom were obtained in 12 out of 20 patients(60%), and recurrence of symptom were in 6 of 20 patients(30%). It is considered that epidural block will shorten the time of recovery from severe pain, avoid hospitalization or long periods of bed rest and allow earlier physiotherapy. In addition it may avoid the need for surgical intervention to produce rapid relief of acute pain and give to patient economic, psychologic benefit.