Secure fixation of lumbar osteotomy. Surgical experience with 50 patients.

Despite intensive conservative treatment, severe kyphotic spinal deformities may develop in patients with ankylosing spondylitis. Lumbar osteotomy can restore a horizontal visual field in these patients. Of 50 patients undergoing corrective lumbar osteotomy, there were 44 men and 6 women. A transpedicular screw and cable system was used in 37 patients. Mean correction of deformity was 38.7 degrees. Mean loss of correction was 4.8 degrees, but was 15 degrees in those cases in which transpedicular fixation was not used. All patients were able to see straight ahead after the operation. There were 2 deaths and 1 permanent sacral root lesion. Fixation failure was seen in 2 of 37 patients in whom transpedicular implants were used and in 3 of 13 in whom alternative methods of internal fixation were used.