Results of One Stage Thoracoscopic Spinal Release and Posterior Osteotomies for Correction of Kyphotic Deformity in Ankylosing Spondylitis

Objective: In severe rigid curves of ankylosing spondylitis (AS), multiple posterior osteotomies alone frequently fail to offer adequate correction. Anterior osteotomies via conventional thoracotomy impose a substantial trauma to the rigid chest cage of an AS patient. This retro-spective study evaluates clinical results, radiological correction and morbidity following combined thoracoscopically assisted osteotomies/fusion and posterior corrective osteotomies done one stage in prone position.

Patients and Methods: From 1996 through 1999, twenty-four patients with progressive kyphotic deformity of the thoracic (n=14) and thoraco-lumbar (n=10) spine underwent combined videoassisted anterior osteo-tomy and fusion, and posterior multiple osteotomies with transp. fixation. The average age of the patients 46 years(32-59).18 males and 6 females. Eighty levels posteriorly and sixty-nine levels anteriorly were osteoto-mised in 24 patients. The avg. thoracic kyphosis angle was 69 degrees (51-89), the average lumbar lordosis 23 degrees(0-45) and the cobb angle of the planned area for ventro-dorsal osteotomies 18 degrees in average (5-40). The mean follow up period is 41 months (24-62months).

Results: The mean amount of correction was 34.5 degrees (15-60). The mean degree of loss of correction was 6.5 degrees (0-12) at the final follow up. The operative time of endoscopic procedure was 80 minutes (50-110). In no case was conversion to emergency open thoracotomy necessary. Judged by clinical and radiographic parameters, excellent and good results were obtained in 22 patients (91.6%) at the final follow up. All patients were satisfied with cos-mesis. There was no mortality, vascular or neurological complication.

Conclusions: Thoracoscopic anterior osteotomy and fusion proved to be a safe and effective procedure allowing an adequate circumferential release when combined with posterior corrective osteotomies in AS.