Abstract: In a lower limb prothesis an energy storing foot (10) is combined with a resilient ankle joint (13) which is arranged to allow plantar flexion but substantially to prevent dorsi-flexion. The ankle joint (13) comprises a ball and socket joint (42), the socket (44) of which is extended downwardly on the anterior, medial and lateral sides to form a skirt (44A) positioned so as to compress a resilient ring (54) encircling a ball member (46) of the ball and socket joint (42). Metal plates (56) are embedded in the anterior part of the ring to prevent significant dorsi-flexion. The foot (10) has a single-piece carbon fiber reinforced plastics keel (12) having a lower spring portion (12B) connected at its posterior end as a cantilever to an upper ankle mounting portion (12). The resilient of the foot (10) is adjustable by means of a transversely extending support bar (28) which can be moved longitudinally by rotating an adjusting screw (30).

Abstract: In a lower limb prosthesis an energy storing foot is combined with a resilient ankle joint which is arranged to allow planatar flexion but substantially to prevent dorsiflexion. The ankle joint comprises a ball and socket joint, the socket of which is extended downwardly on the anterior, medial and lateral sides to for a skirt positioned so as to compress a resilient ring encircling a ball member of the ball and socket joint. Metal plates are embedded in the anterior part of the ring to prevent significant dorsiflexion. The foot has a keel having a lower spring portion connected at its posterior end as a cantilever to an upper ankle mounting portion. These two portions may be formed as a single carbon fibre reinforced plastics moulding or individually as part of a two-piece keel with the ankle mounting portion rigid and the spring portion as simple fibre-reinforced strip.

Abstract: An artificial leg has a ball and socket ankle joint, the socket of which has upper and lower portions. They are connected together and clamped over the ball by a turnbuckle ring. This provides an adjustable shin and foot connection which permits use of a rubber-encased ball of sufficient size, without taking up too much shape within the ankle region. Also disclosed is a movable patella member and a vertically jointed two part foam covering.

Abstract: An artificial leg employs a knee mechanism having a multi-bar linkage (1, 3, 4, 7, 9, 12). The leg is intended for patients having a disarticulated knee amputation or an above-knee amputation with a long thigh stump, the mechanism being situated in the upper part of the calf. The geometry of the linkage is such that the mechanism has a fixed or virtually fixed axis of rotation (16) which is projected outside the confines of the mechanism into the space occupied by the end portion of the stump. Since the mechanism is uniaxial and internal, a relatively good external appearance can be obtained.