Effects of Toe-out and Toe-in Gait with Varying Walking Speeds on Knee Adduction Moment and Mechanical Work Done-A Pilot Study

Abstract

Knee joint is subjected to loads during activities of daily living. Higher loads can cause deterioration of the joint and malalignment. Toe-in and toe-out gait are among the techniques that modify the posture in order to minimize these loads. Several studies have reported their effects in reducing knee joint load. No effects of these techniques, however, have been reported with varying walking speeds on knee adduction moment (KAM) and mechanical work done at lower limb joints. The aim of this study was to investigate the effects of self-selected toeing-in and toeing-out with self-selected normal, slow and fast walking speeds on first and second peaks of KAM, individual lower limb joints mechanical work and total lower limb mechanical work done during level walking. A pilot study was conducted using cinematographic gait analysis of 5 healthy young adults (age: 28 years; weight: 58.3 kg, height: 1.6 m) walking at self-selected normal, slow and fast walking speeds for each of the three foot positions: straight (natural), toe-out and toe-in. Repeated measures ANOVA (p < 0.05) was applied with pairwise comparison to find the differences between groups. The results showed that there are significant effects of changing foot progression angle on knee joint loads and on positive and negative muscle work done. Also, the analyses showed that walking speed has a prominent influence on the relationship of foot progression with knee joint load and with mechanical work. Therefore, it is suggested that walking speed should also be considered while prescribing toe-out and toe-in gait. Further researches with a broader spectrum of walking speeds may identify the optimal speed for each foot position.