Abstract
<jats:p>Thoracic scoliosis is commonly associated with rib cage deformity and impaired respiratory mechanics. Derotational breathing exercises aim to correct three-dimensional trunk asymmetry by selectively expanding the concave hemithorax. This prospective quasi-experimental study investigated the effects of a 4-week supervised Schroth-based rotational angular breathing (RAB) program on intercostal distance (ICD), vertebral axial rotation, and Cobb angle in 20 female adolescents (age 14.30 ± 1.84 years; mean follow-up 33.45 ± 4.26 days) with thoracic idiopathic scoliosis. Radiographic measurements were obtained at the apical vertebra using Surgimap digital analysis. After intervention, concave upper ICD increased by 1.90 mm (p = 0.003) and concave lower ICD by 1.90 mm (p = 0.033), while convex ICD remained unchanged (p > 0.05). Raimondi vertebral rotation decreased by 4.75° (p = 0.002, dz = 0.807). Cobb angle reduction (1.75°) was not significant (p = 0.133). These preliminary findings suggest that structured derotational breathing may function as an active biomechanical force capable of expanding the collapsed concave thorax and reducing vertebral rotation in the short term.</jats:p>