title: Comparison of disc and vertebral wedging between patients with adolescent idiopathic scoliosis and Chiari malformation-associated scoliosis.
abstract: METHODS
  A comparative study.
  
  
  OBJECTIVE
  To investigate the difference of disc and vertebral wedging between patients with adolescent idiopathic scoliosis (AIS) and Chiari malformation-associated scoliosis (CMS).
  
  
  BACKGROUND
  The wedging of disc and vertebral wedging of AIS are well investigated. However, the comparison of that wedging between AIS and CMS is not found in the literature.
  
  
  METHODS
  This study included 35 cases of AIS and 31 cases of CMS. The disc and vertebral wedging was measured by Cobb method. The percentage of single disc and vertebral wedging in the whole thoracic or lumbar curve was calculated. The difference between disc and vertebral wedging, the apical vertebra and average adjacent vertebrae wedging, the apical discs and adjacent discs wedging in the same curve location, same diagnosis and similar Cobb angle group was compared. The difference of disc or vertebral wedging between AIS and CMS, Cobb angle <60 degrees and ≥60 degrees was also compared. The correlation between the apical vertebral wedging angle and Cobb angle was performed by Pearson correlation analysis.
  
  
  RESULTS
  The difference between disc and vertebral wedging in the same curve location, same diagnosis, and similar Cobb angle group was statistically significant (P<0.05). No significant difference of the disc or vertebral wedging was found between AIS and CMS in the same curve location and the similar Cobb angle group (P>0.05). No significant difference of the disc or vertebral wedging was found between Cobb angle <60 degrees and ≥60 degrees groups in the same curve location and the same diagnosis (P>0.05). There was a positive correlation between the apical vertebra wedging angle and Cobb angle in AIS patients and CMS patients. The wedging of apical vertebra and disc was more than that in the adjacent disc and vertebra in the same curve.
  
  
  CONCLUSIONS
  The relative wedging of intervertebral disc and vertebrae with AIS patients is similar to that of scoliosis with known cause (CMS). The wedging of discs and vertebrae in AIS patients may be an adaptive change secondary to some extravertebral factors.
authors: Spine Surgery, Drum Tower Hospital, Nanjing University Medical School, Nanjing, China.
authors: Shoufeng
authors: S
authors: Wang
authors: Yong
authors: Y
authors: Qiu
authors: Weiwei
authors: W
authors: Ma
authors: Bin
authors: B
authors: Wang
authors: Yang
authors: Y
authors: Yu
authors: Bangping
authors: B
authors: Qian
authors: Zezhang
authors: Z
authors: Zhu
authors: Feng
authors: F
authors: Zhu
authors: Xu
authors: X
authors: Sun