Pedicle subtraction osteotomy through pseudarthrosis to correct thoracolumbar kyphotic deformity in advanced ankylosing spondylitis

Introduction  

Surgical treatment is mandatory for spinal pseudarthrosis in advanced ankylosing spondylitis (AS) patients with painful sagittal deformity and/or neurological deficits. However, the most effective and safe surgical procedure for AS-related symptomatic thoracolumbar pseudarthrosis is still controversial. The purpose of this study is to explore the outcomes of pedicle subtraction osteotomy (PSO) at the level of pseudarthrotic lesion combined with supplemental anterior fusion for patients suffering from kyphotic pseudarthrosis in AS.