In vivo geometrical evaluation of Cheneau-Toulouse-Munster brace effect onscoliotic spine using MRI method

Objectives. The aim was to quantify the immediate effect of the Cheneau-Tou louse-Munster brace (worn at night) on scoliotic curvatures in vivo. Design. A three-dimensional geometrical model of the spine was developed us ing magnetic resonance images. Background. Many corrective ortheses were proposed For the orthopaedic trea tment of idiopathic scoliosis. Simple radiographs were not sufficient to an alyse the three-dimensional spinal deformations. So. three-dimensional geom etrical models were developed using stereoradiography and axial tomography, MRI has been only used clinically for investigation of intervertebral disc disorders. Method. MRI examination had been performed on 14 girls having an idiopathic scoliosis and wearing a first Cheneau-Toulouse-Munster brace. The protocol investigated was performed with and without brace. Using an in-house image processing software and the pre-post processing software Patran, two geome trical models of the spine (spine without brace and spine with brace correc tion) were obtained, respectively, for each patient, the models including t he vertebral bodies. Results. Our method reproducibility was found to be 0.5 mm on the displacem ents and 2.5 degrees on the rotations. The Cheneau-Toulouse-Munster brace d ecreased the coronal shift forward, the coronal tilt, the axial rotation, a nd increased the sagittal shift forward and the sagittal vertebral tilt. Discussion. The results showed that the Cheneau-Toulouse-Munster brace had a three-dimensional and personalised action on vertebrae. This technique us ing MRI provides no irradiation and allows the soft tissue visualisation, b ut actually is not dedicated for clinical use and is limited to the lying p osition.