Influence of Stiffness of an Ankle-foot Orthosis on Gait a Predictive Simulation Study

An ankle-foot orthosis (AFO) is often prescribed to patients with instability or weakness in the lower leg to assist plantarflexion or dorsiflexion [1]. A limited number of studies focuses on the optimal stiffness of the AFO. It is known that excessive AFO stiffness introduces buckling in the knee [1]. It would be desirable to have the ability to predict the effect of an AFO on the gait of a specific patient. This would make customized prescriptions possible and reduce the need for trial and error. Bregman et al. used a simplified gait model and found that patient energy cost might be reduced by choosing the correct stiffness [2]. However, this model did not have muscles.