A single-axis prosthetic foot is a commonly used ankle–foot component in the prosthetic field, designed to allow motion in one primary plane—plantarflexion and dorsiflexion. This controlled up-and-down movement is achieved through a mechanical hinge at the ankle, often combined with elastic bumpers or stops to regulate motion during walking.
From a clinical perspective, single-axis feet are especially beneficial for new amputees, elderly users, and individuals with limited balance or knee stability. By allowing rapid plantarflexion immediately after heel strike, the foot promotes early foot flat, which improves stability and reduces the risk of knee buckling. This makes it a reliable choice for low to moderate activity levels (K1–K2).
Although single-axis feet do not store or return energy like dynamic response feet, they offer predictable gait mechanics, durability, and ease of alignment. Prosthetists often select this foot for patients who prioritize safety, simplicity, and consistent performance over high energy return.
