Purpose: EOS imaging system is accessible to clinicians since 2007, allowing 3D spinal reconstructions in a functional standing position with reduced radiation. However, numerous ongoing research protocols continuously help implementing the dedicated software. The main principle and applications of the EOS device are discussed here, with an emphasis on future projects. In particular, the authors studied the postoperative modification of the rib cage and spinal morphology after posteromedial correction, in a consecutive series of adolescent idiopathic scoliosis (AIS) patients.
Methods: 49 thoracic AIS patients underwent low-dose stereoradiography preoperatively, postoperatively and at latest examination, with a minimum 2-year follow-up. Spinal and rib cages 3D reconstructions were obtained using dedicated software, and the postoperative modification of thoracic parameters was reported.
Results: All parameters were significantly improved after surgery. Mean thoracic volume increase was 8.4% (±8), influenced by the postoperative derotation of the apical vertebra. No difference was found in thoracic volume increase in patients who gained more than 10° of thoracic kyphosis. A significant correlation was found between spinal penetration index at the apex and thoracic sagittal alignment (p = 0.02).
Conclusions: EOS imaging device now reliably provides a global 3D quantitative analysis of scoliotic deformities in a context of routine clinical use. This innovative tool will help in the future to better understand scoliosis physiopathology and to evaluate treatment strategies.