Biomechanical Correlates between Foot Arch Morphology and Sports Injury Risks: a Multifactorial Analysis of 1078 University Students

Objective: This study aimed to investigate the relationship between foot arch structure and lower limb biomechanical parameters and to quantify the effects of arch morphology on postural stability, plantar pressure distribution, foot elasticity, and related structural deformities. Methods: A cross-sectional study was conducted involving 1078 university students (569 males and 509 females; mean age = 20.18 ± 1.43 years). The iFEET Neo 3D system was used to measure arch height, hallux valgus angle, and calcaneal angle, whereas the iGAIT MAX 3D system assessed plantar pressure distribution, center of gravity displacement, mediolateral pressure center deviation, arch elasticity index (AEI), and pressure recovery rate (PRR). A Kistler force platform (Model 9286B) was used to calculate the coordination asymmetry index (CAI) and the Hurst exponent of the center of pressure trajectory. Multivariate linear regression and mixed-effects models were employed to examine the associations between foot arch type and the measured biomechanical parameters. Results: Arch height demonstrated significant association with multiple biomechanical indicators. Individuals with high arches exhibited a marked increase in hallux valgus angle ( B = 35.303, P < 0.001), and each 1 mm decrease in arch height was associated with a 2.45° increase in calcaneal eversion ( B = –2.447, R ² = 0.828) and a considerable increase in CAI. A 1 mm increase in bilateral arch height difference corresponded to a 10.7 mm shift in the center of gravity and a 1.58 mm mediolateral displacement in the pressure center ( P < 0.001). Reduced arch height was associated with a marked decline in foot elastic function; specifically, AEI decreased by 62.4 points in the flatfoot++ group (95% confidence interval: –63.379, –61.363), accompanied by a corresponding reduction in PRR. The Hurst exponent deviated significantly from 0.5 in individuals with abnormal foot structures, indicating decreased dynamic postural stability. Conclusion: Abnormal foot arch morphology is closely associated with the impaired biomechanical function of the foot, including reduced postural stability, diminished energy storage and return capacity, and angular deformities. These findings provide a quantitative foundation for injury risk identification and functional foot assessment, and support the integration of arch structure screening into student health management programs.