Static Plantar-Load Distribution and Stabilometry in Children and Adolescents with Idiopathic Scoliosis Under...

Background/Objectives: Adolescent idiopathic scoliosis (AIS) is associated not only with structural spinal deformities but also with alterations in postural control and sensorimotor integration. Objective assessment of balance and plantar-load distribution may provide additional insight into functional impairments, particularly in patients with mild and moderate curves. The aim of this study was to compare static plantar-load distribution and stabilometry parameters in children and adolescents with idiopathic scoliosis under different sensory and postural conditions. Methods: This pilot study included 19 children and adolescents (18 female, 1 male) diagnosed with mild and moderate AIS. Load distribution and stabilometric parameters were assessed using a capacitive platform under three testing conditions: eyes open, eyes closed, and head extension. Parameters evaluated included load distribution across plantar regions and center-of-pressure-related stability measures. Comparisons were performed between conditions to evaluate the influence of visual and vestibular modulation on postural control. Results: Total plantar load did not differ between the right and left foot, and global relative plantar-load distribution remained stable across the three testing conditions. A consistent side-to-side asymmetry was present at the fifth metatarsal head, where load on the left side was significantly lower than on the right in every condition and remained significant after Holm correction for multiple comparisons (p = 0.001-0.002; |r| = 0.94-0.99). Higher left-sided load was also observed at the first metatarsal head and heel; the heel asymmetry remained significant after correction only in the eyes-open condition (Holm p = 0.044), whereas the remaining differences did not survive correction and are reported as exploratory. The left side corresponded to the side of lumbar convexity. Postural stability differed markedly between conditions: center-of-pressure path length, 90% confidence-ellipse area and maximum center-of-pressure speed were greater under the eyes-closed and head-extension conditions than with eyes open, indicating reduced postural stability when visual input was removed or head position was altered. The two challenge conditions did not differ significantly from each other. Conclusions: In this uncontrolled pilot study, children and adolescents with mild-to-moderate idiopathic scoliosis showed a consistent reduction in load under the left fifth metatarsal head, whereas, apart from a higher left heel load that was significant only with eyes open, other regional asymmetries were exploratory. Stabilometric parameters deteriorated under both visual deprivation and head extension, with no statistically significant difference between the two challenge conditions. Because postural changes became apparent mainly when visual or head-position conditions were altered, assessment under such conditions may reveal condition-related changes in postural control within this AIS cohort. However, because no healthy control group was included, these findings should not be interpreted as evidence of AIS-specific sensory-integration deficits. These preliminary findings require confirmation in larger controlled studies including healthy age-matched participants.