Three-Year Randomized Follow-Up of Achilles Tendon Shortening in Prepubertal Children

Abstract Achilles tendon shortening (ATS) is a clinically relevant factor influencing gait mechanics and foot development in childhood. This three-year longitudinal study investigated ATS progression and its biomechanical implications in the same cohort of prepubertal children evaluated annually in 2022, 2023, and 2024. ATS severity was graded using a Silfverskiöld-based protocol, and foot morphology was quantified using the Chippaux–Smirak, Staheli, and Chizhin indices. Across the follow-up period, ATS exhibited a significant progressive increase (repeated-measures ANOVA F = 27.69, p < 0.0001), with Tukey post-hoc analysis confirming distinct differences between all assessment years. Concurrently, foot-type distribution shifted toward a greater prevalence of collapsed arches, and chi-square testing demonstrated a moderate but significant association between ATS severity and arch classification (p = 0.0039). Gait deviations—including prolonged pronation and altered foot progression angle—were consistent with compensatory adaptations. These findings highlight ATS as a progressive biomechanical modifier during childhood and underscore the importance of early identification and targeted intervention.