During a 5 year period 50 patients with chronic low back pain, with or without sciatica due to a proven lumbosacral disk lesion, underwent a spinal fusion using the Boucher method of screw fixation of the facet joints. The L-4 spinous process was excised and fashioned into an H-shape to act as the bone graft between the spinous processes so avoiding an iliac crest incision. Thus blood loss and operating time were substantially diminished. The screws maintain fixation for an 8-week period during which time the graft is "taking." Being inserted with spinous processes distracted about 1 cm the screws and the graft take the load off the painful posterior part of the annulus, and in addition, the distraction of the spinous processes enlarges the intervertebral foramina by about 1 cm thus making subsequent foraminal stenosis unlikely. Loosening of the screws after incorporation of the graft was observed in some cases, but was not considered to be clinically significant. Spinal fusion using screws for internal fixation including indications and contraindications requires careful consideration of operative technique, postoperative management and complications. The clinical evolution of 86% of the patients was rated good or fair from a clinical standpoint; 86% showed a fusion; 14% demonstrated a pseudarthrosis. Three of the 7 pseudarthrotic patients had a good clinical result. The other 4 had only a fair clinical result. Nine of the 14 patients with fair clinical results had a fusion radiologically; all 7 of the clinically unimproved had a fusion. Since the graft is placed at least 1 cm dorsal to the laminae, spinal cancal stenosis is extremely unlikely.