Single-Case Study: Traditional Thermoplastic AFO Versus Adjustable Dynamic Response™—A Crossover Single-Case Study

In Brief Past studies have suggested that ankle-foot orthoses (AFOs) improve walking; however, it is unclear what biomechanical designs are most effective. This 10-week trial investigated the effects of a traditional thermoplastic style AFO compared with an Adjustable Dynamic Response™ (ADR™) AFO in a single-case subject. The subject was a 74-year-old man affected by postpolio syndrome with a prior history of AFO use. Patient usage and activity levels were measured with a StepWatch™ Activity Monitor, gait characteristics were measured with a GAITRite® System, and patient satisfaction was measured with a standardized AFO satisfaction questionnaire. The subject wore the traditional AFO for the first 5 weeks of the trial and the ADR™ AFO for the remaining 5 weeks of the trial. Weeks 1 and 5 were considered washout periods, and data were not collected for these weeks with the StepWatch Activity Monitor. Patient usage and activity levels were improved in the ADR™ AFO over the traditional AFO showing an average of 6,606 steps per day in the ADR™ AFO compared with 4,504 steps per day in the traditional AFO. The subject also spent more time engaged in moderate to high activity levels, versus low activity levels, in the ADR™ AFO compared with the traditional AFO. Gait characteristics, such as increased velocity and increased step length, were improved in both AFOs compared with no AFO at all with slightly higher improvements in the ADR™ AFO over the traditional AFO. The AFO satisfaction questionnaire suggested a higher level of patient satisfaction in the ADR™ AFO over the traditional AFO. This single-case study provides insight for future clinical research designs comparing AFOs and how to quantify outcomes such as patient usage and activity levels in an AFO, temporal-spatial gait parameters with an AFO, and patient satisfaction with an AFO. For this patient, activity level, velocity, and patient satisfaction all improved when wearing the ADR AFO versus the traditional AFO, suggesting a positive correlation between activity levels, gait velocity, and patient satisfaction.