Abstract: An improved prosthetic foot achieves minimal weight, robust structure, and anatomically correct behaviors by means of structural arrangement and maximized material application. The improved prosthetic foot includes a forefoot leaf spring longitudinally strengthened by a raised or inverted channel and a heel assembly having a non-linear loading response as the heel member is depressed during a gait cycle. A forefoot according to the invention has a mean flexure line substantially parallel to, and forwardly displaced from, the Tc axis of rotation of an equivalent intact foot. The forefoot leaf spring channel provides a hinging action that allows for the expression and isolation of rotational forces at the front of the forefoot (inversion and eversion) separate from the rear of the foot. The hinging action also helps advantageously distribute the pressure of the body weight on the foot in a manner akin to a natural foot.

Abstract: With the present invention, improved prosthetic foot devices including whole foot devices, heel assembly devices and forefoot devices are provided that address these and other concerns. For example, a prosthetic foot device is provided that includes a heel assembly coupled to a forefoot device through a rotary flexure coupling. In one embodiment, a heel assembly is provided that comprises a resilient heel member and a heel mount. The heel mount is adapted for connection in the prosthetic foot. It has a contact surface for engaging a portion of the heel member to establish in it an effective spring length. The contact surface engages different portions of the heel member for different phases of a gait cycle when the heel member is being loaded thereby effectively shortening the heel member's spring length and providing it with a non-linear loading response as it is being depressed in the gait cycle. In another embodiment, a forefoot is provided that includes a proximal end and a distal end.