Purpose of study: The spectrum of discogenic pain syndrome ranges from internal disc disruption (IDD), degenerative disc disease (DDD) and segmental instability. After failure of conservative treatment, surgical options would include fusion. This study was performed to determine whether the results of fusion differ between IDD and DDD.Methods used: Patient and radiographic data were entered prospectively on 118 patients who underwent anterior lumbar interbody fusion for treatment of low back pain. Chart and radiographic review completed data sets. Of the 118 patients, 53 had IDD and 65 had DDD. We evaluated each group for clinical outcome, Oswestery scores, and radiographically for fusion, subsidence, and lordosis. In patients with IDD, average age was 39 years. There were 15 smokers (28%) and 16 patients (30%) were involved in workman's compensation litigation. Twelve patients had previous lumbar spine surgery. Two level fusions were performed in 6 patients. Average follow-up period was 29 months. In patients with DDD, average age was 44 years. There were 16 smokers (25%) and 11 patients (17%) were involved in workman's compensation litigation. Twenty-four patients had previous lumbar spine surgery. Two level fusions were performed in 2 patients. Average follow-up period was 27 months. In both groups minimal follow-up was 12 months.of findings: In patients with IDD, excellent/good results were obtained in 44 patients (83%) and fair/poor results in 9 patients (17%). Oswestery Scores were an average of 38 points pre-op which improve to 24 points at 3 months and to 20 points at the last follow-up visit. Radiographic fusion occurred in 50 patients (94%). The intervertebral height was increased from 4.5 mm pre-op to 7 mm post op and then decreased due to subsidence to 5 mm. Lumbar lordosis at the fused level measured an average of 17 degrees pre-op, 20 degrees immediately post-op and 21 degrees at last follow-up. In patients with DDD, excellent/good results were obtained in 60 patients (92%) and fair/poor results in 5 patients (8%). Oswestery Scores were an average of 36 points pre-op, which improve to 20 points at 3 months and to 10 points at the last follow-up visit. Radiographic fusion occurred in all 65 patients (100%). The intervertebral height was increased from 3 mm pre-op to 7 mm post op and then decreased due to subsidence to 5.5 mm. Lumbar lordosis at the fused level measured an average of 14 degrees pre-op, 21.4 degrees immediately post-op and 21.7 degrees at last follow-up.Relationship between findings and existing knowledge: This study demonstrates that anterior lumbar interbody fusion provides excellent outcomes both clinically and radiographically when indicated for treatment of discogenic low back pain.Overall significance of findings: Radiographically, restoration of lordosis and disc height was better achieved in patients with DDD. In addition, we found that patients with DDD had better clinical outcomes than patients with IDD.Disclosures: No disclosures.Conflict of interest: Thomas A. Zdeblick, grant research, consultant, Medtronic.