Effect of pedicle subtraction osteotomy on spino-pelvic parameters in ankylosing spondylitis patients with thoracolumbar kyphosis / 中华骨科杂志

ABSTRACT

ObjectiveTo explore the change of spino-pelvic parameters following pedicle subtraction osteotomy (PSO) for thoracolumbar kyphosis secondary to ankylosing spondylitis(AS).MethodsTwenty-one AS patients with thoracolumbar kyphosis,who underwent PSO at L1 level from July 2006 to October 2010 in our hospital,were retrospectively reviewed.There were 18 males and 3 females with a mean age of 35.6 years (range,21-53 years).The pre- and post-operative thoracic kyphosis(TK),lumbar lordosis (LL),globe kyphosis (GK),angle of the fusion levels (AFL),sagittal imbalance (SVA),pelvic incidence (PI),sacral slope (SS) and pelvic tilting (PT) were measured.ResultsSignificant differences were observed in terms of the improvement of LL,PT,SS,SVA,GK and AFL (P＜ 0.01).The alteration of LL showed significant correlation with the change of PT (r=0.59,P=0.005),SS (r=0.64,P=0.002),SVA (r=0.49,P=0.025),and AFL (r=0.60,P=0.004).The change of PT exhibited cardinal correlation with the change of SS(r=0.94,P=0.000).The improvement of AFL significantly correlated with the improvement of SS(r=0.61,P=0.003),PT (r=0.59,P=0.005).ConclusionThe change of the sagittal spino-pelvic profile following PSO in AS-related thoracolumbar kyphosis is closely related with the improvement of LL.