ABSTRACT
The resulting spinal kyphosis due to the Progressive flexion deformity in ankylosing spondylitis is a challenging issue where thoracolumbar osteotomies are to be of consideration in the correction of the global sagittal and gaze alignment as treatment modalities. The purpose of this retrospective clinical study was to evaluate the clinical and radiological results of posterior closing wedge osteotomy that we performed in the treatment of kyphotic deformities in the patients with ankylosing spondylitis. Eleven patients having kyphotic thoracolumbar deformities due to ankylosing spondylitis were included in the study and they were treated with posterior transpedicular closing wedge osteotomy followed by long-segment posterior instrumentation. After a mean follow-up period of 43.5 ±18.7 months patients were evaluated in terms of Cobb angle measurements and clinical results. Additionaly, 7 of 11 patients were assessed in terms of SRS-22 questionnaire for pain, self image and satisfaction of treatment. The mean preoperative thoracic kyphosis which was 87.3° ± 4.3° improved to 54.0° ± 9.5° postoperatively (p<0.05). At the final follow-up it was 58.2° ± 9.1° with an average correction loss of 4.2° ± 2.5°. The mean preoperative lumbar lordosis was 19.6° ± 6.3°. Than it improved to 39.6° ± 5.7° (p<0.05) postoperatively and were 37.0° ± 5.5° at the final follow-up with an average correction loss of 2.6° ± 2.3°. Preoperative, postoperative and final mean sagittal balance values were 6.6 ± 2.3 cm, 3.1 ± 1.5 cm (p<0.05) and 3.4 ± 1.6 cm, respectively. Loss of correction in sagittal balance was 0.23 ± 0.26 cm in the last control visit. In the all patients whom were applied SRS-22 questionnaire; the levels of pain, appearance, mental status, function and satisfaction of treatment revealed results of minimum 4 points. There was no death, neurological compromise, implant failure, pseudoarthrosis or infection, but one pulmonary embolism and one postoperative thoracic kyphosis proximally to the osteotomy level. We concluded that; posterior transpedicular closing wedge osteotomy followed by long-segment posterior instrumentation in the management of kyphotic deformities due to ankylosing spondylitis seems to be an effective procedure in terms of satisfactory sagittal balance and implant survival.