Iliopsoas muscle thickness and pelvic alignment in pronated and normal foot postures

Abstract

It is hypothesized that the subtalar hyperpronation may provoke the development of a biomechanical chain of events in lower extremity alignment. Several studies have shown that pelvic alignment may alter in the presence of immediate foot hyperpronation induced by external forces. It is unknown whether these alterations are presented in chronic foot hyperpronation or not. It is also unknown if these potential postural changes could affect iliopsoas muscle size. Therefore, it appears necessary to carry out thorough research in this study. Twenty nine females with pronated foot posture and twenty seven females with normal foot posture participated in this study. The iliopsoas muscle was measured using ultrasound imaging (USI). Pelvic angle (PA) was measured using reflective markers and digital photography. Intrarater reliability of USI for the iliopsoas muscle thickness was also measured. The results indicated that the iliopsoas muscle thickness and the PA were not different in individuals with pronated foot compared to the normal foot group. However, a good intrarater reliability of USI was found for measuring the iliopsoas muscle thickness.

Keywords: Hyperpronation; Iliopsoas; Pelvic angle; Ultrasound imaging.