[Brace effect in scoliosis in the sagittal plane - an MRI study].

Aim: Using magnetic resonance (MR) imaging we studied the brace effect in scoliosis in the sagittal plane.

Method: In 38 patients with idiopathic scoliosis (mean age 13.4 years) MR total spine imaging was carried out to investigate the immediate effect of bracing in the sagittal plane. There were 19 thoracic, 13 S-shaped and 6 lumbar scoliosis. On conventional radiographs the mean Cobb angle of the thoracic curves was 31 degrees and of the lumbar curves 26 degrees. MR imaging was performed in the supine position with and without the brace in direct sequence. On the sagittal MR projection the Cobb angle was measured between T 4 and T 12 and between T 12 and L 5.

Results: On the coronal MR images the mean correction with brace was 23 % of the thoracic curves and 29 % of the lumbar curves. The mean, sagittal Cobb angle (T 4 - T 12) was 14 degrees without brace and 12 degrees with brace. For the lumbar curves the mean sagittal Cobb angle (T 12 - L 5) was 32 degrees without brace and 31 degrees with brace. In the paired t-test these differences were significant.

Conclusion: Using MR total spine imaging the brace effect in scoliosis could be depicted in the sagittal plane. In the thoracic spine a correction of the lordotic deformity could not be observed.