As a potential improvement to energy-storage and return feet, which incorporate various design features including split toes, an energy-storage and return foot with a dedicated ankle joint was recently introduced that allowed for easily accessible inversion/eversion movement. The adaptability of energy-storage and return feet to uneven ground and the effects on biomechanical and clinical parameters, however, have not been investigated in detail.
A recent study aimed to determine the design-related ability of prosthetic feet to adapt to cross slopes and derive a theoretical model. Mechanical adaptation to cross slopes was investigated for six prosthetic feet measured by a motion capture system. A theoretical model linking the measured data with adaptations was proposed. The type and degree of adaptation depends on the foot design, for example, stiffness, split toe or continuous carbon forefoot, and additional ankle joint. The model used shows high correlations with the measured data for all prosthetic feet.
The ability of prosthetic feet to adapt to uneven ground is design-dependent, the study found. The split-toe feet adapted better to cross slopes than those with continuous carbon forefeet. Joints enhance this further by allowing for additional inversion and eversion. The influence on biomechanical and clinical parameters should be assessed in future studies.
Thestudy, Characterizing adaptations of prosthetic feet in the frontal plane, was published in Prosthetics and Orthotics International.