Identifying Postural Dysfunction as a Common Phenotype in Flatfoot, Pronated Foot, and Genu Valgum: A Cross-Sectional Study in the Pediatric Population

Background: To investigate the association between symptomatic flexible flatfoot, pronated foot, and genu valgum and global postural alignment in children and adolescents, with particular focus on pelvic and spinal parameters and patterns of pain localization. Methods: A cross-sectional observational study was conducted on a cohort of 2,130 individuals evaluated for postural dysfunction. A paediatric subgroup (=126) between the ages of 6 and 10 years (Mage = 8.50, SD = 1.78), presenting with symptomatic lower-limb deformities was selected. Participants were classified into three groups: symptomatic flexible flatfoot (n = 64), pronated foot (n = 38), and genu valgum (n = 24), based on clinical and radiographic criteria including Foot Posture Index (FPI-6), Staheli Arch Index, Meary’s angle, talo-calcaneal angle, and femoro-tibial angle. Global postural alignment was assessed using optoelectronic analysis and weight-bearing radiographs. Results: Neutral postural alignment was infrequently observed. Recurrent patterns included pelvic anteversion and mild variations in sagittal spinal curves, generally within paediatric reference ranges. Frontal-plane deviations were common but predominantly mild. Differences between groups were mainly related to distribution rather than magnitude of postural variations. Pain was described according to anatomical location. Conclusions: Lower-limb deformities in children appear to be associated with specific patterns of postural adaptation rather than isolated segmental alterations. However, findings should be interpreted cautiously due to the absence of a control group and the cross-sectional design. Further studies are required to determine clinical relevance.