Effect of six weeks of ankle stretching exercises on ankle dorsiflexion range of motion and anterior knee pain in children with ankle pronation: a randomized controlled trial

Abstract

This study investigated the effect of six weeks of ankle-stretching exercises on anterior knee pain (primary outcome) and ankle dorsiflexion range of motion, genu recurvatum, stride length, and walking speed (secondary outcomes) in children. The study was motivated by the role of ankle dorsiflexion range of motion in lower-limb function. In this randomized controlled trial with pre-test–post-test design, 40 children aged 6–10 years were assigned to an intervention group ( n = 20) or a control group ( n = 20). The intervention group performed ankle-stretching exercises for six weeks; the control group continued usual activities without intervention. Ankle dorsiflexion range of motion and genu recurvatum angle were measured with a goniometer, anterior knee pain was assessed using the Wong–Baker FACES Scale, and stride length and walking speed were recorded with the Kinova tool. Analysis of covariance (ANCOVA) and the Mann–Whitney U test were used to assess between-group effects at a significance level of 0.05. The Mann–Whitney U test showed significant between-group differences at post-test for dorsiflexion range of motion of the soleus and gastrocnemius, anterior knee pain severity, and genu recurvatum angle ( P < 0.05). Marginal means analysis confirmed the effectiveness of the exercises on dorsiflexion (soleus and gastrocnemius) and anterior knee pain ( P < 0.05). ANCOVA indicated no significant change in stride length or walking speed after six weeks ( P > 0.05). Six weeks of ankle-stretching exercises significantly improved ankle dorsiflexion, anterior knee pain, and genu recurvatum in children with ankle pronation. This low-cost intervention may be a useful component of clinical management; however, because walking speed and stride length did not improve, combining stretching with strengthening or gait-specific training may be required for broader functional gains. IRCT20240306061185N7, retrospectively registered at the Iranian Registry of Clinical Trials on 2026-06-09.