Article

Technological advances in prosthetic design include the use of
microprocessors that adapt device performance based on user motion. The Proprio
ankle unit prepositions the foot to adjust for walking on slopes and increases
foot clearance during swing to minimize gait deviations. Study design:
Comparative analysis. Objectives: To investigate the effect of a prosthesis with
adaptive ankle motion on physiological gait performance during slope walking.
Methods: Six persons with a unilateral transtibial amputation completed treadmill
walking tests at three slopes (-5 degrees , 0 degrees , and 5 degrees ). The
participants were tested wearing a customary device, active Proprio (Pon), and an
identical inactivated Proprio (Poff). Results: Metabolic energy expenditure,
energy cost for walking, and rating of walking difficulty were not statistically
different between the Pon and Poff for all tested slopes. However, for slope
descent, energy expenditure and energy cost for walking improved significantly by
an average of 10%-14% for both the Pon and Poff compared to the customary limb.
Rating of walking difficulty also showed an improvement with slope descent for
both the Pon and Poff compared to the customary device. An improvement with slope
ascent was found for Pon compared to the customary limb only. Conclusions:
Adaptive ankle motion provided no meaningful physiological benefit during slope
walking. The Proprio was, however, less demanding than the customary device for
slope descent. Differences in the mechanical properties of the prosthetic feet
likely contributed to the changes. Clinical relevance While the adaptive ankle
motion did not affect metabolic energy expenditure or energy cost for walking,
the results suggest close attention should be paid to the mechanical properties
of the foot component. Assessment of gait on nonlevel surfaces is recommended to
better understand the implications of different prosthetic design features.

Langue : ANGLAIS