ASSESSMENT OF SAGITTAL ALIGNMENT PARAMETERS IN ADOLESCENTS WITH SEVERE IDIOPATHIC THORACIC SCOLIOSIS

BACKGROUND: The concept of sagittal balance has become increasingly important in recent years in the treatment of patients with spinal deformities of various etiologies. Studies devoted to the study of sagittal balance parameters in patients with idiopathic scoliosis are isolated and rarely include patients with severe forms.

AIM. To evaluate the parameters of global and regional sagittal balance in adolescent patients with severe forms of idiopathic thoracic scoliosis.

MATERIALS AND METHODS: The study included 45 patients aged 12 to 17 years with idiopathic thoracic scoliosis (types 1, 2 and 3 according to the Lenke classification) with the magnitude of the primary arc of deformation from 80° to 150° according to Cobb. The patients underwent X-ray examination, regional and global parameters of sagittal balance, characteristics of spinal deformation in the frontal plane were assessed. Depending on the values ​​of the global sagittal balance parameters, the patients were divided into 2 groups. The obtained data were subjected to descriptive, correlation, regression and comparative statistical analysis.

RESULTS: A positive correlation was found between the values ​​of the spine deformation in the frontal plane and the magnitude of thoracic kyphosis; according to the regression analysis, with a magnitude of the main arc of more than ≈100°, an increase in the values ​​of thoracic kyphosis of more than 60° is noted. Increased thoracic kyphosis was the main deformation in the sagittal plane in these patients; however, neither the TK value nor the magnitude of the main arc of curvature in the frontal plane statistically significantly correlated with any of the global sagittal balance indicators. To a greater extent, these indicators correlated with the spinal-pelvic parameters (PI, PT, SS, LL, PI-LL).

CONCLUSIONS: Surgical treatment of severe forms of idiopathic scoliosis must necessarily take into account correction methods that have a corrective effect on the kyphotic component of the deformation. The development of pronounced anterior imbalance was not typical for patients with idiopathic scoliosis of the thoracic localization, even with the largest values ​​of the main arc of deformation. The main risk factors for its development are reduced values ​​of PI and LL. The mechanism for the development of the detected dependence in these patients remains unclear.