Transpedicular Wedge Osteotomy for Correction of Thoracolumbar Kyphosis in Ankylosing Spondylitis: Experience With 78 Patients

Study Design. This is a retrospective study of surgical correction of thoracolumbar kyphosis caused by ankylosing spondylitis. Objective. To report the surgical results of thoracolumbar kyphosis deformity corrected with transpedicular wedge osteotomy performed by a single surgeon at a university hospital. Summary of Background Data. There has not been a large series in the literature reporting on results of the Thomasen-type closing wedge osteotomy for correction of kyphosis deformity secondary to ankylosing spondylitis, nor has two-level osteotomy of this type in one patient ever been described. Methods. From 1991 through 1998, 92 transpedicular wedge osteotomies were performed in 78 patients with ankylosing spondylitis for correction of fixed flexion deformity of the thoracolumbar spine. Results. The mean amount of correction for each level of osteotomy was 34.5° (range, 15°-60°). The largest amount of overall correction for a single patient was 100°. Most of the osteotomies (64 of 92) were done at L2 and L3. Fourteen patients with severe deformity required staged two-level osteotomy. Excellent and good results were obtained in 77 patients (98.7%) at the final follow-up. There was no mortality, nor were there any major neurological complications. Conclusions. Transpedicular wedge osteotomy can effectively and safely correct kyphotic deformity of the thoracolumbar spine caused by ankylosing spondylitis, regardless of rigidity of the spinal curves. Two-level osteotomy can provide sufficient correction for severe cases.