Running Title: Lateral Wedge Inserts With and Without Arch Support.
This study compared immediate changes in knee and ankle/subtalar biomechanics with lateral wedge orthotics with and without custom arch support in people with knee osteoarthritis and flat feet. Compared to the control, lateral wedge and lateral wedge with arch support reduced the knee adduction moment (load on the medial knee compartment) by 8% and 6%, respectively. However, the lateral wedge resulted in a more everted (pronated) foot position than lateral wedge plus arch support. In contrast, lateral wedge plus arch support reduced foot frontal plane excursion compared to other conditions. Participants self-reported significantly more immediate comfort with lateral wedge plus arch support compared to the control, whereas there was no difference in self-reported comfort between lateral wedge and control.