Researchers tested gait biomechanics, walking energy cost, speed, and perceived walking ability in polio survivors with calf muscle weakness to determine if dorsiflexion-restricting ankle-foot orthoses (DR-AFOs) improved walking efficiency in that population. The findings indicate that DR-AFOs did improve walking efficiency, but that the overall effect may depend on the user’s gait pattern when he or she is not wearing the DR-AFO. The results were published on June 18 in the journal Gait and Posture.
For the study, 16 participants who had polio and continue to have calf muscle weakness underwent 3D gait analyses to assess gait biomechanics. Tests were conducted while the participants wore a DR-AFO and again when they wore only shoes. A six-minute walk test was used to determine participants’ walking energy cost and comfortable gait speed. Perceived walking ability was assessed using participant-completed questionnaires designed for the study.
According to the study’s authors, “walking with the DR-AFOs significantly increased forward progression of the center of pressure (CoP) in mid-stance, and it reduced ankle dorsiflexion and knee flexion in mid- and terminal stance,” when compared with the shoes-only tests. The researchers also wrote that walking energy cost was lower and gait speed was higher. The participants reported that they felt more satisfied, safer, and less fatigued when using a DR-AFO. However, the authors noted, the effects of the DR-AFO varied largely across the participants; those who walked with limited forward CoP progression and continued knee extension during the shoes-only portion of the test seemed to have benefitted least from the DR-AFO. The researchers suggested further study to determine which patients will benefit most from the DR-AFO.