Improvement of abdomen and digestive function in patients with ankylosing spondylitis kyphosis following pedicle subtraction osteotomy

English Keywords:Thotacolumbar kyphosis  Ankylosing spondylitis  Abdomen  Digestive function

English Abstract:

  【Abstract】 Objectives: To investigate the improvement of abdomen and digestive function in patients with ankylosing spondylitis kyphosis following pedicle subtraction osteotomy. Methods: From January 2009 to July 2013, 53 patients in our department with severe ankylosing spondylitis kyphosis and undergoing pedicle subtraction osteotomy were studied, there were 48 males and 5 females. All the patients underwent pedicle subtraction osteotomy(PSO), the segment of osteotomy was L1-L3. The globe kyphosis(GK) was measured in the whole spine X-ray photo preoperatively and at 18 months after surgery. Three- dimensional reconstruction was performed on all patients. The average of abdominal median sagittal plane(AMSPA) and the minimum distance(MD) between xiphoid process and spine or between abdominal wall and spine when the abdominal wall was folded into abdomen were measured on the three-dimensional computed tomography(3D-CT) scans. A health related quality of life including Oswestry Disability Index and Scoliosis Research Society outcomes instrument-22 and weight were recorded preoperatively and at 18 months after surgery. Digestive function assessment included the food intake(FI), and the change of defecate frequency was recorded at 18 months after surgery, the patients were divided into group A(no change) and group B(obviously increased according to intake changes), and group 1(no change ) and group 2(significantly increased according to the defecate frequency changes). Results: Obvious improvement in ODI, weight and SRS-22 in all the patients at 18 months after surgery(P<0.05) was noted. The GK decreased significantly at 18 months after surgery(P<0.05). MD and AMSPA increased significantly compared with pre-operation(P<0.05). The distances from porta hepatic, hilum of spleen, left renal hilum to margo superior of symphysis pubis were longer compared with those of pre-operation(P<0.05). The distance between right renal hilus and mago superior of pubic symphysis showed no statistical significance compared with that of pre-operation(P>0.05). 29 patients showed significant improvement of defecate frequency at 18 months after surgery, however 20 patients showed no change(P<0.05). 33 patients showed significant improvement of food intake at 18 months after surgery, however 24 patients showed no change. There were no significant differences in terms of age, course of diseases between group A and group B(P>0.05). GK value of group A was significantly greater than that in group B, which was the same with group 1 and group 2(P<0.05). Conclusions: The conditions of extrusion of viscus by trunk flexion and decreased volume of the abdominal cavity are improved in patients with ankylosing spondylitis kyphosis after osteotomy, followed by digestive function improvement.