Enhancing static alignment in hyperpronated feet using custom medial and lateral supports in R-AFO: A Pilot study

The ankle-foot complex plays a vital role in stability and mobility, with its dysfunction leading to gait abnormalities. Rigid ankle-foot orthoses (R-AFOs) are commonly used to address anteroposterior instability, but their effectiveness on static mediolateral alignment, particularly in cases of hyperpronation, remains unclear. This study examines the impact of incorporating medial and lateral supports into R-AFOs on enhancing mediolateral alignment. To assess whether adding medial and lateral supports to R-AFOs improve static mediolateral alignment in individuals with hyperpronation by analyzing changes in the resting calcaneal stance position angle (RCSPA). Nine individuals (mean age 20.56 ± 3.22 years) with flexible hyperpronation were recruited. Adjustable medial and lateral supports (3 mm, 6 mm, 9 mm, and 12 mm) were tested within a R-AFO. RCSPA changes were measured to quantify mediolateral alignment changes and pain levels were recorded. Statistical analysis was conducted using Friedman and Wilcoxon signed-rank tests. Lateral support significantly reduced pronation (Z = -2.561, <i>p</i> = 0.01), with a 6 mm depth providing optimal correction (4.83° reduction). Medial support had minimal impact, and higher depths (9 mm, 12 mm) caused discomfort. Lateral support within R-AFOs effectively enhances mediolateral alignment in individuals with hyperpronation, offering a simple and cost-effective intervention. Further research is needed for clinical validation.