The Benefit of a Flexible Ankle-Foot Orthosis on Balance and Walking Ability in Persons With Late Effects of Polio: A Mixed-Methods Study

Abstract

ABSTRACT Introduction Many persons with late effects of polio (LEoP) have muscle weakness in the lower limbs, which affects their balance and walking ability. Although an ankle-foot orthosis (AFO) is commonly prescribed for these persons, there is limited knowledge if an AFO improves their balance and walking ability in terms of speed, distance, and perceived safety. The aims of this study were 1) to assess if a flexible AFO improves dynamic balance as well as indoor and outdoor walking in persons with mild to moderate LEoP and 2) to describe the participants' own perceptions of walking ability and safety, as well as advantages and disadvantages with an AFO. Materials and Methods A mixed-methods, repeated-measures, crossover design was used. Nineteen participants were assessed at two test occasions, with and without an AFO, with a 1-week interval. Dynamic balance was evaluated with the timed up and go (TUG) test and walking ability by the 10-m fast gait speed (FGS) tests, the 6-minute walk test (6MWT), and timed walking over a 340-m-long pathway outdoors. The Borg Rating of Perceived Exertion (RPE) scale was used to assess perceived exertion. The participants' perceptions of their walking ability and safety as well as advantages and disadvantages with an AFO were evaluated with questionnaires. Results The AFO significantly improved (P < 0.05) gait speed, outdoor walking, and reduced perceived exertion at one of the test occasions, but had no effect on dynamic balance (P > 0.6). A majority perceived significantly improved walking ability (P < 0.05) and increased walking safety (P < 0.01) with the AFO. Perceived advantages of the AFO were feelings of increased stability and walking distance and reduced risk of falling. Disadvantages were that it could be difficult to put on and uncomfortable to wear. Conclusions A flexible AFO marginally improves walking ability in persons with LEoP, as assessed quantitatively, but the subjective benefit of walking ability and safety suggests that a flexible AFO can be useful to improve daily functioning. In the future, the design of the AFOs needs to be more user-friendly.