Optimal exercise prescription parameters in Schroth training for adolescent idiopathic scoliosis: a systematic review and meta-analysis.

BACKGROUND

Adolescent idiopathic scoliosis (AIS) affects 0.5%-5% of the adolescent population, representing the most common spinal deformity in this age group. This systematic review and meta-analysis aimed to determine optimal exercise prescription parameters for Schroth training in AIS by examining dose-response relationships between exercise frequency, duration, and clinical outcomes.

METHODS

Systematic searches of PubMed, Scopus, Web of Science, and SPORTDiscus were conducted following PRISMA 2020 guidelines. Randomized controlled trials examining Schroth interventions in adolescents aged 10-18 years with idiopathic scoliosis were included. Network meta-analysis was performed using MetaInsight platform for Cobb angle outcomes, with traditional pairwise meta-analyses conducted for all outcomes using standardized mean differences with 95% confidence intervals.

RESULTS

15 randomized controlled trials encompassing 620 participants were included. The overall meta-analysis demonstrated Schroth exercises produced statistically significant Cobb angle improvements (SMD = -0.52, p < 0.0001; I2 = 0%). Subgroup analysis revealed dose-response relationships favouring moderate exercise frequencies (3-4 sessions/week), which showed the largest pooled effect (SMD = -0.58, I2 = 3%). Duration analysis demonstrated medium duration interventions (46-75 min) provided the most precise improvements (MD = -2.92°), while optimal frequency was the moderate (MD = -2.79°, 95% CI: -4.05, -1.48). Combined subgroup analysis identified moderate frequency plus medium duration as the most robust combination (SMD = -0.65, I2 = 10%). Health-related quality of life outcomes showed non-significant improvements with substantial heterogeneity (SMD = 0.52, p = 0.43; I2 = 93%). Secondary outcomes showed statistically significant improvements in trunk rotation (SMD = -0.86, p = 0.002; I2 = 22%) and cosmetic appearance perception (SMD = -0.73, p = 0.01; I2 = 0%), while postural stability measures showed non-significant effects (SMD = 0.08; p = 0.81; I2 = 68%). Publication bias assessment using Egger's test shows no statistically significant funnel plot asymmetry (p = 0.745).

CONCLUSIONS

Exploratory subgroup and network meta-analyses suggest that moderate frequency Schroth exercises (3-4 sessions/week) combined with medium duration sessions (46-75 min) may represent optimal parameters for Cobb angle improvement in AIS. Non-linear dose-response patterns show diminishing returns at higher frequencies, challenging conventional exercise prescription assumptions. These findings require validation through prospective studies with pre-specified dose-stratification examining long-term effectiveness, cost-effectiveness, and patient adherence across diverse healthcare contexts before broad clinical implementation.