Asymmetric 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 asymmetry of anterior chest wall blood supply and subsequently to aetiology of idiopathic thoracic scoliosis in female adolescents. Recent investigations on the anterior chest wall blood supply with Colour Doppler Ultrasonography (CDU) in such individuals did not show anatomical 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 horacolumbosacral orthosis (TLSO) and 20 age-matched girls, without spine deformity (controls) were studied with CDU [internal mammary artery (IMA)] twice within the 2-year period. IMA-anatomical parameters [lumen diameter (D) and cross sectional area (AR)] as well as hemodynamic flow parameters [time average mean flow velocity and flow volume per minute (FV)] were measured. In the 2-year-period of observation, TLSO prevented scoliosis progression (P = 0.004), while 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), while 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 physiological 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 pre-brace levels in scoliotics was the most significant finding of this investigation. In conclusion, this study provided evidence 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.