Abstract: Objective    To explore the changes of balance related parameters and influencing factors in adolescent idiopathic scoliosis (AIS) after brace treatment.    Methods    A total of 82 patients with AIS who received brace treatment in our hospital from June 2012 to December 2021 were selected as the research objects. Before treatment and at the last follow-up after treatment, X-ray films of the whole spine in the natural standing position were taken. According to whether the absolute value of radiographic shoulder height (RSH) after treatment was greater than that before treatment, the patients were divided into the double shoulder balance group and the double shoulder imbalance group. The shoulder balance parameters of the two groups were compared, and the correlation between RSH and imaging indexes was analyzed. The influencing factors of shoulder imbalance in patients with AIS after brace treatment were discussed by multivariate Logistic regression analysis.    Results    After treatment, the incidence of shoulder imbalance was 23.17%. Before brace treatment, clavicular angle (CA) and clavicular contour angle difference (CCAD) in the double shoulder imbalance group were higher than those in the double shoulder balance group (P<0.05). Compared with before treatment, RSH, upper thoracic curve Cobb angle, main thoracic curve Cobb angle, CA and T1 inclination angle were significantly improved in the two groups after 6 months of treatment and 2 years of treatment, and the improvement effect was better in the double shoulder balance group (P<0.05). RSH after treatment was significantly positively correlated with CA and CCAD before treatment in the double shoulder imbalance group (r=0.896, 0.882, P<0.05),  and negatively correlated with upper chest bending  flexibility  (r=-702, P<0.05). The change of RSH after treatment was significantly positively correlated with the change of CA, the change of upper thoracic curvature angle, the correction rate of upper thoracic curvature, the change of main thoracic curvature angle and the correction rate of main thoracic curvature (r=0.906, 0.644, 0.708, 0.815, 0.878, P<0.05). Risser's sign > 3, initial Cobb's angle ≥ 35° and vertebral rotation ≥ III degree were independent risk factors for shoulder imbalance after brace treatment (P<0.05).   Conclusions   RSH, upper thoracic curve Cobb angle, main thoracic curve Cobb angle, CA and T1 tilt angle were significantly improved in AIS patients after brace treatment. Risser’s sign, initial Cobb angle and vertebral rotation were independent risk factors for shoulder imbalance in AIS patients after brace treatment.

Key words: Adolescent idiopathic scoliosis; ,  , Brace treatment; ,  , Shoulder balance; ,  , Influence factor