Anterior decompression and stabilization of thoracolumbar burst fractures by the use of the Slot-Zielke device. Between July 1983 and November 1986, 29 patients with thoracolumbar burst fractures underwent a one-stage operation consisting of anterior decompression by subtotal vertebrectomy, reduction, and stabilization with the Slot-Zielke device. The mean follow-up was 3.1 years. Most patients with incomplete neurologic lesions showed postoperative improvement and were upgraded one or two steps in the Frankel scale. No patient showed neurologic deterioration after surgery. In all patients, bony union occurred. Loss of reduction of more than 5 degrees occurred in 41% of the patients. Because of this high rate of loss of reduction in patients and the low degree of flexion-bending loading and torsional stability in biomechanical evaluation in vitro of the Slot-Zielke device on human cadaveric spines, an additional posterior stabilization of the spine after an anterior approach for anterior- and middle-column fractures should be considered. 