The Effects of Ankle Foot Orthosis Heel Height and Stiffness on Gait in Adults with Below-Knee Impairments

What this Trial Is About

Researchers are evaluating how the height and stiffness of the heel in ankle foot orthoses (AFOs) affect the forces and motion of the lower limbs during walking in people who regularly use an AFO. This study involves individuals with unilateral or bilateral below-knee impairments caused by musculoskeletal injury, disease, or peripheral nervous system disease. The goal is to provide evidence to help clinicians and researchers better align AFOs to improve everyday walking function. Participants will walk over ground while wearing their usual clinical AFO and with heel cushions of different heights and stiffnesses (four conditions) placed inside their shoes. They will walk at controlled and self-selected speeds, and if possible, also without their AFO. The study uses randomized testing orders of various heel wedge conditions including tall and short wedges made of soft or firm foam, as well as a no-AFO condition. During the study, lower limb forces and body motion will be measured using motion capture with small reflective markers on the skin and force plates in the floor. Participants will also provide information about their health and their preferences regarding the different heel wedge conditions. The primary outcomes include measures of center of pressure velocity, comfort, pain, and wedge preference, with additional assessments of ankle motion and power. The study is led by the University of Iowa and participation lasts across the testing sessions.

The Effects of AFO Heel Height and Stiffness on Gait