Tibial stress fractures and other lower extremity injuries can be treated using an ankle foot orthosis (AFO). AFOs are popular because they allow the patient to ambulate somewhat naturally while reducing weight bearing on the injured limb. Despite their popularity, it is currently unclear how well AFOs reduce lower extremity weight bearing.

The first objective of this investigation was to examine the ability of three commonly used ankle foot orthoses to reduce weight bearing within the lower limb by comparing the ground reaction force measured from a force platform to the force measured from an insole pressure measurement device inside the AFO. Results indicated that the corset-style AFO was more effective in reducing the load compared to the camwalker and patellar-tendon bearing AFOs.

The second objective was to examine and quantify the kinematic and kinetic changes made in the natural gait pattern of the participants when wearing an AFO. Wearing an AFO alters the geometry and inertial properties of the limb which causes the wearer to alter their natural gait pattern which could lead to addition problems such as low back pain. Results indicated that the camwalker AFO changed gait the most, the patellar-tendon bearing AFO altered gait to some extent, and the corset-style AFO changed gait minimally.