Evolution of anterior chest wall blood supply in female adolescents with progressive right-convex thoracic idiopathic scoliosis.

Breast asymmetry was believed to be related to the asymmetry of anterior chest wall blood supply and subsequently to etiology of idiopathic thoracic scoliosis in female adolescents. Recent investigations on the anterior chest wall blood supply with colour Doppler ultrasonography in such individuals did not show anatomic and hemodynamic abnormalities. The present study investigated the evolution of anterior chest wall blood supply in these individuals over a 2-year period. Twenty female adolescents with progressive right-convex idiopathic thoracic scoliosis (scoliotics), who were during the study in therapy with thoracolumbosacral orthosis and 20 age-matched girls, without spine deformity (controls) were studied with colour Doppler ultrasonography [internal mammary artery (IMA)] twice within the 2-year period. IMA-anatomic parameters [lumen diameter (D) and cross sectional area (AR)] and also hemodynamic flow parameters [time average mean flow velocity (TAM) and flow volume per minute (FV)] were measured. In the 2-year period of observation, thoracolumbosacral orthosis prevented scoliosis progression (P=0.004), whereas IMA-AR decreased bilaterally in the individuals of both groups (P<0.03). In the last evaluation: in scoliotics right IMA FV decreased (P<0.04), whereas in controls IMA FV decreased bilaterally (P<0.03); left IMA FV was significantly higher (P<0.05) in scoliotics than in controls. The significant, within the 2-year period, decrease of IMA-diameter, cross-sectional area, and flow volume seems to be a physiologic ageing process because it was observed in all individuals (scoliotics and controls) and thus these anatomic and hemodynamic changes seem not to have been affected by bracing. The maintenance of left flow volume of IMA in the prebrace levels in scoliotics was the most significant finding of this investigation. In conclusion, this study provided evidences for abnormalities in the evolution of anterior chest wall blood supply in female adolescents with progressive right-convex female thoracic scoliosis. Further studies are needed to investigate if this asymmetric blood evolution contributes to the development of this pattern of scoliosis in girls.