Introduction: Until now, the non-surgical therapeutic approach for idiopathic scoliosis (IS) was based on rigid brace using three points pressure and distraction technique. For the first time we wanted to use a dynamic approach for the treatment of IS. For this goal we have developed a Dynamic Correction Brace (DCB) or SpineCor to use the forces of the dynamic spine to optimise the reduction of spinal curves and permit neuromuscular integration during the period of correction.

Methods and results: The effectiveness of the treatment depends on the reducibility of the curve with the brace. The goal of this study is to quantify the reducibility of scoliosis curves through a study of the variation of Cobb angle, during and after treatment.

Between 1993 and 1999, 113 adolescents with classic indications of idiopathic scoliosis were treated by the same orthopaedist with the DCB. The mean age at the beginning of the treatment is 12.9 years old. The potential reducibility (PR) of the curves was estimated by the percentage of reduction of the initial Cobb’s angle corresponding to the maximum correction obtained during the course of treatment and after the treatment for the patient at maturity. Fifty patients have completed their treatment and are at maturity.

From this cohort of patients treated by the DCB, 73.4% had a reduction of 5° or more than their principal Cobb angle; 22.8% were stable, but non-reducible, with a change of less than 5°; and 3.8% conserved an evolutive potential, with an increase in the Cobb angle of 5° or more. A significant difference was evident for PR between the group presenting an initial Cobb angle < 30° and those presenting an initial Cobb angle > 30° (p< 0.05). 65.8 per cent of the patients presented with an initial Cobb angle < 30° for a mean PR of 40.6% and were categorised according to the following: a) 26% of the patients had a PR ≤20%; b) 41% obtained a PR between 20% and 50%; and c) 33% had a PR > 50%. The other patients (34.2%) with an initial Cobb > 30° and a mean PR 22% were also categorised: 39% had a PR ≤20%; b) 48% had a PR between 20% and 50% and c) 13% > 50%. For patients who have completed their treatment 85% have a correction or are stabilised, 15% are worse or needed surgery during the treatment. For these patients, 53% have a correction of < 20%, 31% have a correction between 20 and 50%, and 16% have a correction of > 50%.

Conclusion: The reducibility of the curve during the treatment is very informative concerning the prognosis treatment. The effectiveness of a DCB is comparable to effectiveness of other rigid braces for which the results have been published.