Initial In-Brace Correction of Adjustable Versus Traditional Rigid Braces in Adolescents With Idiopathic Scoliosis: A Retrospective Case-Control Study

Multidisciplinary Clinician & Clinical Researcher Hands-on international experience in spine rehabilitation, scoliosis management, and evidence-based clinical research. Skilled in STATA analysis, systematic review methodology, and manuscript preparation. Experienced in clinical protocol design, medical device testing, training healthcare teams, and presenting research at international conferences. Passionate about bridging clinical practice, research, and innovation to improve patient care and advance rehabilitation science Reference: Background Bracing effectively alters adolescent idiopathic scoliosis (AIS) progression when initial in-brace correction (IBR) exceeds 40-45%, with >90% of successful cases achieving up to 70% IBR. However, treatment efficacy depends critically on compliance, which is compromised by discomfort, aesthetic concerns, and quality of life impacts. Novel brace designs addressing these barriers while maintaining biomechanical correction principles may improve patient acceptance. We developed an adjustable thoracolumbosacral orthosis (TLSO) featuring instant adjustment capabilities for growth adaptation, exercise integration, and pressure fine-tuning across three dimensional planes. This preliminary study assessed the feasibility and initial corrective efficacy of this adjustable TLSO compared to traditional rigid TLSOs. Objective To compare initial IBR between an adjustable TLSO incorporating growth-adaptive features and 3D correction principles versus traditional non-adjustable TLSOs in adolescents with AIS, and identify patient factors associated with correction magnitude. Methods This was a retrospective study involving in 23 AIS patients (91.3% female, mean age 12.0 ± 0.95 years) treated between 2022–2025. They were assigned to either adjustable (n = 13) or conventional (n = 10) braces, according to orthotist recommendation and patient preference. Both brace types followed 3D design principles, prescribed for full-time daytime wear (18-22 hrs.). The adjustable brace incorporated modifiable underarm and posterior components to accommodate breathing and growth and allow fine-tuning of corrective forces and was fabricated using lighter materials intended to improve comfort and tolerability. Primary outcome measure was IBR percentage measured by standing PA radiographs obtained within one month of brace fitting: [(Cobb pre-brace - Cobb in-brace)/Cobb pre-brace]×100. Statistical analysis employed Mann-Whitney U tests for group comparisons, Spearman correlations for associations (α=0.05), and sensitivity analyses excluding outliers. Results Baseline characteristics were comparable between groups for age (11.8±0.93 vs 12.4±0.97 years, p=0.077), BMI (16.9±2.1 vs 16.9±2.3 kg/m², p=0.967), and pre-brace Cobb angle (33.8±4.9° vs 31.8±9.2°, p=0.515). However, Risser stage distribution differed significantly (p=0.032), with adjustable patients exhibiting lower skeletal maturity. Median IBR was 68.8% (IQR: 52-100%) for adjustable braces versus 85% (IQR: 45.7-100%) for traditional braces, with no statistically significant difference (z=-0.377, p=0.735). Both designs substantially exceeded the 40% IBR threshold associated with treatment success (90% adjustable vs 100% traditional achieved ≥40%, p=0.435). Sensitivity analyses confirmed robustness (p=0.678). Greater initial curve severity inversely correlated with correction percentage (ρ=-0.485, p=0.020), while higher BMI also showed negative correlation (ρ=-0.472, p=0.024). Age (ρ=-0.290, p=0.178) and Risser stage (ρ=-0.340, p=0.111) were not significantly associated with IBR magnitude. Conclusions The Adjustable braces displayed comparable initial IBR to conventional braces in AIS. Its design assisted the biomechanical feasibility. Its customizable feature, lighter weight and appealing appearance also mead it more popular to patients. Limitations include small sample size (n=23), absence of compliance monitoring, lack of sagittal plane analysis, and short-term assessment. Prospective studies with objective compliance monitoring, patient-reported outcomes, and minimum 12-month follow-up are warranted to evaluate sustained correction and treatment effectiveness.