Correlation between coronal wedge deformity and sagittal spinal curvature in adolescent idiopathic scoliosis: a retrospective analysis

The correlation between the Cobb angle and the sagittal spinal curvature (SSC) in adolescent idiopathic scoliosis (AIS) has been reported in some previous studies, but few studies have reported on the relation of coronal wedge deformity (CWD) with sagittal curvature. This study aims to investigate the correlation between CWD and SSC in AIS patients. A retrospective analysis was conducted in 122 AIS patients treated at our hospital from January 2018 to November 2023. Correlation analysis was performed on the Cobb angle, total wedge angle(TW), apical vertebral wedge angle (APW), upper end-vertebral wedge angle (UW), lower end-vertebral wedge angle (LW), total affected structures, average wedge angle(AW), total vertebral wedge angle (TVW), average vertebral wedge angle (AVW), Vertebral Wedge Angle ratio (VWR), total disc wedge angle (TDW), average disc wedge angle (ADW), and disc wedge angle ratio (DWR). Furthermore, out of all cases which underwent lateral spinal radiographs, a correlation analysis between thoracic kyphosis (TK), lumbar lordosis (LL) and CWD was carried out on 102 patients. The Cobb angle exhibited a significant positive correlation with multiple CWD parameters (P < 0.05). TK showed a significant negative correlation with the Cobb angle (r = - 0.221, P = 0.026), TW (r = - 0.199, P = 0.045), AW (r = - 0.262, P = 0.008), TDW (r = - 0.211, P = 0.033), and ADW (r = - 0.278, P = 0.005). LL had no significant correlation with TK and other parameters (P > 0.05). In mild and moderate AIS patients, CWD parameters were positively correlated with the Cobb angle and negatively correlated with thoracic SSC. This may indicate that it's necessary to correct sagittal thoracic curvature when rectifying scoliosis in clinic. This research would not only provide new insights for clinical practice but also offer important evidence for early diagnosis and intervention.