The outcome of a modified version of the Cheneau brace in adolescent idiopathic scoliosis (AIS) based on SRS and SOSORT criteria: a retrospective study

Abstract

Background: Bracing therapy for patients with adolescent idiopathic scoliosis (AIS) continues to be a controversial issue. As a consequence, to achieve an adequate level of evidence, there is a strong need for specific studies conducted according to standard outcome and management criteria.

Aim: To assess the outcomes of a modified version of the Cheneau brace, ("Cheneau-P") in patients with AIS, based on SRS and SOSORT criteria.

Design: Retrospective study.

Setting: Scoliosis Unit of a Clinical Center.

Population: Sixty-seven patients, 56 females and 11 males.

Methods: Inclusion criteria were: diagnosis of AIS, age ≥10 years, Risser Score 0-2, Cobb degrees 20-40, no previous treatment, beginning of brace treatment within 1 year after menarche and minimum 2-year follow-up. According to SRS criteria, bracing outcomes were classified, as follows: "improved" (reduction of the curve ≥6°), "unchanged" (5° curve progression or reduction), "worsened" (≥6° curve progression), and "over 45°" (curve exceeding 45° or undergone surgery during the follow-up). The outcomes "improved" and "unchanged" were considered as successful outcomes. Groups and related subgroups were created according to curve type (thoracic, thoraco-lumbar, lumbar and double major) and magnitude (20°-30°; 30°-40°) and to skeletal age (Risser score 0, 1, 2). A separate analysis was also performed on the 37 patients, 30 females and 7 males, who completely fulfilled the SRS eligibility criteria, showing spinal curves between 25 and 40 Cobb degrees.

Results: In the whole group SRS outcome after bracing treatment was successful in 93% and in 81% of patients, at per protocol (PP) and intention to treat (ITT) analysis, respectively, the latter also including drop-outs as worst outcomes. Cobb angles significantly decreased in all subgroups except in patients showing double major curves, lower curve magnitude (20-30°) and Risser score 2. Rib humps and balance rate also significantly improved in the whole sample (12.78±4.54 at T0 vs. 6.83±4.33 at T1 P<0.001; 60% at T0 vs. 94% at T1 P<0.001, respectively). In the subgroup that completely fulfilled the SRS eligibility criteria, the outcome was successful in 92% and 83% of patients, at PP and ITT analysis, respectively, the latter also including, even in this case, drop-outs as worst outcomes.

Conclusions: This study shows that in patients with AIS the treatment with the "Cheneau-P" brace is associated with a remarkably high rate of successful outcomes, both in the whole sample and in the subgroup of patients completely fulfilling the SRS criteria.

Clinical rehabilitation impact: The "Cheneau-P" brace proved effective as a conservative treatment for AIS by stabilizing curve progression and limiting the need for surgical treatment.