Scoliosis in strabismus: dominant roles of low BMI and female sex over refractive asymmetry.

PURPOSE: Patients with strabismus are at substantially elevated risk for scoliosis. This study aimed to determine whether anisometropia confers any independent or additive risk for scoliosis within this specific, high-risk population.

METHODS

This retrospective cross-sectional study included 561 strabismus surgery candidates aged 10-35 years. Scoliosis was radiographically defined as a Cobb angle ≥ 10°. Anisometropia was defined as a spherical equivalent difference ≥ 1.0 D. We performed multivariable logistic regression, subgroup analyses, and interaction tests to evaluate associations between scoliosis and demographic, systemic, and ocular factors.

RESULTS

The prevalence of scoliosis was 19.6%. Female sex (adjusted OR = 1.62, 95% CI: 1.05-2.51, p = .032) and lower BMI (adjusted OR = 0.85 per 1 kg/m2 increase, 95% CI: 0.78-0.91, p < .001) were independent risk factors. In contrast, anisometropia showed no association with scoliosis (p = .901), and no dose-response relationship existed between their severities (p = .593). Interaction effects between anisometropia and other ocular factors were not statistically significant.

CONCLUSIONS

In strabismus patients, scoliosis risk is primarily associated with systemic factors (low BMI, female sex) rather than refractive asymmetry. The null finding for anisometropia supports the sensory reweighting hypothesis, indicating its impact may be masked in the context of a profound binocular defect. These results redirect clinical screening focus toward anthropometric and sex-based assessment.