Burst fractures of lower lumbar spine are rare and have not been well delineated in the literature. Treatment and management considerations for lower lumbar burst fractures are somewhat different from the rest of spine because this area only has the cauda equina and nerve roots. The purpose of this study was to analyse the clinical and radiological results and to determine operative approach. The authors analysed the 16 patients who had been treated with spinal instrumentation (Cotrel-Dubousset, Danek, Kaneda) from Dec. 1990 to Dec. 1994, and following results were obtained. 1. The classification of fracture by Francis-Denis method was B type in 7 cases, A type in 6 cases, E type in 2 cases, and D type in 1 case. 2. By the load-sharing classification, six points or less in 11 patients (first group) and seven or more in 5 patients (second group). In first group lordosis was corrected from 20.4degreespreoperatively to 32.6degrees postoperatively and 24.1degrees at the end of follow-up. In second group lordosis was corrected from 14.8degrees preoperatively to 21.3degrees postoperatively and 0.8 degrees at the end of follow-up. 3. The short segmental fixation through posterior approach yielded good result in the first group, but poor result in the second group with complications including two cases of loss of reduction and one case of screw breakage. As a result, posterior approach might be more perferable in first group and anterior approach in the second group.