School-based screening for scoliosis and foot biomechanical abnormalities: a study of prevalence, plantar pressure, and gait among adolescents in Haidian District, Beijing

Background Adolescent idiopathic scoliosis (AIS) and foot biomechanical disorders are significant public health concerns, impacting physical function and quality of life. Despite national screening mandates, regional data remain sparse. Methods We conducted a school-based screening study to investigate the prevalence of scoliosis and foot-related biomechanical abnormalities among adolescents in Haidian District, Beijing, China. A total of 1,419 participants (739 males and 680 female) from primary and middle schools underwent spinal and plantar health assessments using standardized protocols, including the Adams forward bend test with a scoliometer, Foot Posture Index-6 (FPI-6), and static/dynamic plantar pressure analysis. Results This cross-sectional study of 1,419 Beijing adolescents revealed a 2.04% prevalence of scoliosis (29 cases), showing significant female predominance (3.53% vs. 0.68%; χ 2 = 14.397, p < 0.001, φ = −0.101, Cramer's V = 0.101). Scoliosis prevalence showed distinct developmental patterns, with a significant increasing trend across grades ( p = 0.011). Clear peaks were observed in 6th (4.22%) and 9th (4.35%) grades, where cases significantly exceeded expected counts, though the reliability of estimates for upper grades (11th-12th) may be limited by smaller sample sizes (48 and 18 participants, respectively). In contrast, the detection rate of foot abnormalities was slightly higher among males (47.8% vs. 43.4%), this difference did not reach statistical significance ( p = 0.098), and the effect size was negligible (Phi = 0.044). This indicates that foot abnormalities represent a common health concern affecting both sexes. Significant variation in foot abnormality prevalence was observed across grades [ χ 2 (11) = 36.98, p < 0.001], peaking sharply at school entry (62.7% in 1st grade) and then declining rapidly through elementary school. Prevalence stabilized during middle adolescence, with a non-significant apparent rebound in the small 12th-grade sample requiring cautious interpretation. Conclusions Key findings highlight the need for early and targeted interventions within school health programs. A gender-stratified approach is recommended: implementing gender-sensitive screening for scoliosis, while adopting universal promotion measures for foot health. Specific priorities include increasing flatfoot screening frequency among 1st–2nd grade boys and enhancing posture-related health education for adolescent girls during key transitional growth phases. These strategies aim to mitigate long-term musculoskeletal complications.