Between 1983 and 1986, 20 patients were treated by chronic spinal cord stimulation for the relief of pain. These patients suffered from lumbar arachnoiditis or root fibrosis causing lumbar pain and sciatica following operations for disc herniation or repeated radiculography. In this short series, the results obtained were satisfactory, with 12 good results which were stable over a 2-year period, thanks to careful selection of the subjects within the framework of a multidisciplinary pain clinic. The treatment of the fibrosis and the mechanism of neurostimulation are reviewed.