PurposeThe aim of our study was to evaluate thoracic vertebrae rotation in patients with pectus excavatum. Moreover, we wanted to assess the prevalence, the severity and relationship between pectus excavatum and adolescent idiopathic scoliosis (AIS).MethodsWe performed retrospective analysis of 82 preoperative chest CT in children with pectus excavatum performed between January 2008 and December 2011. For each patient Haller Index and Cobb angle was measured. To evaluate the severity of thoracic scoliosis we measured vertebral rotation for Th8 and for vertebra at the level of highest chest deformation using Aaro-Dahlborn method.ResultsFrom the group of 54 patients with pectus excavatum enrolled in the study AIS was diagnosed in 8 patients (14,81%). In patients with symmetric deformation, Th8 rotation was found in 21 patients; the rotation of the apical vertebra was found in 20 patients. In patients with asymmetric deformation Th8 rotation was found in 10 patients; the rotation of the apical vertebra was found in 8 patients.Conclusions1. We have confirmed the higher prevalence of pectus excavatum in boys; 2. We have found a significant relationship between pectus excavatum and adolescent idiopathic scoliosis; 3. We have shown that deformation of the anterior chest wall enforces rotation of the thoracic spine; 4. We haven't found the relationship between the severity of the chest deformity (HI measured) and severity of AIS (Cobb angle measured); 5. We have shown a significant association between HI measured and rotation of thoracic vertebra at the level of highest chest deformation (apical vertebra) in symmetric pectus excavatum.Level of evidence: Level IV, Diagnostic study.