Influence of footedness on dynamic joint stiffness during the gait stance phase

Aims: Dynamic joint stiffness (DJS) is used as a joint stability indicator. The objective of the present study is to verify the influence of footedness in ankle joint stability during the gait stance phase. Study Design: Comparative study. Place and Duration of Study: MovLab/ CICANT/ Universidade Lusófona de Humanidades e Tecnologias, between November 2013 and June 2014 Methodology: 31 subjects (20 female and 11 male) presenting different footedness (right and left) were assessed. Ten gait stance phase trials (five each side) were recorded using a 3D motion capture system and a force platform. Synchronized ankle sagittal moment of force and angular position were used to calculate DJS for three defined sub-phases of gait stance phase: controlled plantar flexion, controlled dorsiflexion and powered plantar flexion. Mann-Whitney U test was calculated to assess footedness influence on biomechanical variables. Results: No significant differences were found between dominant and non-dominant limb in different combinations of footedness and gender. Conclusion: Footedness do not seem to influence DJS and consequent joint stability. Observing the trials per participant, differences can be noted but commonly used statistical approach cannot highlight those differences. Further studies should address ankle frontal plane behaviour or assess differences at the knee and hip joints, as they could present more differences that could be statistically significant.