[Surgical treatment of thoracolumbar spinal fractures with internal fixator and transpedicular spongiosa-plasty].

We report on 30 unstable fractures of the thoracolumbar spine which were operatively treated between 1987 and 1992 with the AO Internal Fixator and transpedicular bone grafting. There were 26 flexion-compression fractures, 2 flexion-distraction injuries and 2 fracture-dislocations. Follow-up ranged from 2 to 5 years. All patients were examined and their histories reviewed. New radiographs were obtained and a standardized questionnaire on pain and on functional and economical status was answered. The radiographical analysis included measurement of the vertebral, segmental and local kyphosis and of the sagittal index. The preoperative vertebral kyphosis averaged +17 degrees and was corrected to +7 degrees at follow-up with the sagittal index improving from 0.59 to 0.86. The segmental respectively local kyphosis was reduced from +15 degrees respectively +8 to +5 degrees respectively -3 degrees. The fractured vertebra remained stable. We registered an average postoperative loss of correction of 4 degrees in the upper disc space due to collapse of the injured disc. The lower disc space was frequently overcorrected which was neutralized postoperatively due to a process of reequilibration of less than 3 degrees. The loss of correction occurred both before and after removal of the implant. There was no significant change of the sagittal plane apart from a successful realignment of the flexion-distraction injuries. Five out of 8 patients with neurological symptoms improved by at least 1 Frankel grade. We had no case of neurological deterioration. The results of the questionnaire were good or very good in 70%. At follow-up, the average back pain score was 3 out of 10, 10 being unbearable pain.