The present foot prosthesis includes various structural features that provide the foot with advantageous rollover properties. In certain embodiments, the foot guides rollover toward the medial side. For example, an asymmetrical upper element and a correspondingly shaped resilient ankle member support...http://www.google.com/patents/US20050267603?utm_source=gb-gplus-sharePatent US20050267603 - Foot prosthesis with resilient multi-axial ankle
