Aim: To prospectively evaluate the results of brace treatment in idiopathic scoliosis and to define risk factors of treatment failure.
Method: Fifty-two patients with a Cobb angle of between 25 and 40 degrees were included in the study. Prior to initiation of brace treatment with the Chêneau-Toulouse-Muenster orthesis, skeletal age and flexibility of the curve (bending films) were evaluated. The average follow-up after weaning of the brace was 42 months (36-78 months).
Results: An average initial Cobb angle of 31 degrees was corrected to 18 degrees (43 %) under brace treatment with a flexibility to 6 degrees Cobb angle on bending films. Three years after weaning there was an overall increase of the Cobb angle to 37 degrees on average. The apical vertebral rotation was corrected from 16 degrees to 11 degrees (31 %) and increased to 20 degrees during follow-up. Thoracic kyphosis changed from 24 degrees to 18 degrees during treatment. At the latest follow-up kyphosis had returned to the pre-treatment angle again. Twenty-two patients had a curve progression during or after brace treatment of more than 5 degrees. In 14 patients surgical correction and fusion have been indicated. There was a positive correlation between flexibility and Cobb angle correction during brace treatment and a negative correlation between Cobb angle correction during brace treatment and curve progression (p < 0.05).
Conclusions: Curve progression was prevented in 58 %. Prognostic risk factors are a young age at initiation of brace treatment, a thoracic curve, unsatisfactory curve correction in the brace and a male gender.