A pilot study published May 19 in Prosthetics and Orthotics International compared crossover feet and energy-storing feet on performance-based tests using a range of low-level (e.g. sit-to-stand) and high-level (e.g. jogging) activities. Study results suggested that while crossover feet may improve low- and high-level mobility, intervention effects were small, and practice effects were observed in all outcomes.
Seven participants who each had a transtibial amputation [VC1] completed a battery of performance-based outcome measures, including the Five-Times Sit-to-Stand, Timed Up and Go, Four Square Step Test, and the Comprehensive High-level Activity Mobility Predictor. Participants wore duplicate prostheses fit with crossover feet and energy-storing feet to perform the tests; the order of foot conditions was randomized. Paired t-tests were used to evaluate differences between feet and order of testing. Data from the participants showed improvements in all measures while using crossover feet. Improvements in the second foot condition were also observed, indicating a practice effect for all measures, the study found. However, differences between feet and order of conditions were not statistically significant.
Crossover feet may improve transtibial prosthesis users’ performance compared to energy-storing feet across a range of activities, but more research is needed, the study found. Future research is also needed to evaluate the influence of practice effects on performance-based mobility measures. Practice effects may be an influential factor in the measurement of performance-based mobility outcomes and should be considered when performing a clinical assessment.