Sagittal range of motion of the thoracic spine using standing digital radiography: A throughout comparison with non-radiographic data reviewed from the literature

Previous studies have measured thoracic range of motion (RoM) using either skin-mounted devices or supine CT-imaging and have reported quite different RoMs. Given the inherent shortcomings of measurements of vertebrae movements from the overlying skin, the present study aims to measure normal RoM of the thoracic spine in the sagittal plane using the upright digital radiography. Lateral radiographs of the thoracic spine were acquired from eight asymptomatic male subjects in upright standing and full forward flexion using a mobile U-arm digital radiographic system. Total (T1-T12), upper (T1-T6), and lower (T6-T12) thoracic RoMs were measured. A throughout comparison with available skin-based measurements in the literature was carried out. Mean of total (T1-T12) thoracic RoM was 22.5° (SD 4.1°), most of which was generated by the lower (T6-T12) as compared to upper (T1-T6) thoracic spine (15.5° versus 7.1°, p measurements suffer from the inter sensor-skin-vertebra movements and supine imaging techniques do not allow maximal trunk flexion, standing radiography remains as the gold-standard technique. Evaluation of thoracic spine RoM has implications in both patient discrimination for diagnosis and in biomechanical models for estimation of spinal loads.