Abstract: A lower limb prosthesis comprises a knee chassis (10), a shin carrier (20) pivotally connected to the knee chassis (10) and a piston and cylinder assembly (30, 40) pivotally connected to the knee chassis (10) and the shin carrier (20). The piston and cylinder assembly (30, 40) comprises a piston assembly (40) comprising a piston (40) mounted on a piston rod (42), a cylinder body (32B) having a cavity (46) defining a cylinder within which the piston (44) is arranged to reciprocate along the piston and cylinder assembly axis, and a foot component attachment means (36) for attaching a foot component to the piston and cylinder assembly (30, 40).

Abstract: A lower limb prosthesis comprises a knee chassis (10), a shin carrier (20) pivotally connected to the knee chassis (10) and a piston and cylinder assembly (30, 40) pivotally connected to the knee chassis (10) and the shin carrier (20). The piston and cylinder assembly (30, 40) comprises a piston assembly (40) comprising a piston (40) mounted on a piston rod (42), a cylinder body (32B) having a cavity (46) defining a cylinder within which the piston (44) is arranged to reciprocate along the piston and cylinder assembly axis, and a foot component attachment means (36) for attaching a foot component to the piston and cylinder assembly (30, 40).

Abstract: In a stabilising knee joint for a lower limb prosthesis, weight-activated knee stabilisation is achieved by interen-gagement of a brake disc (32) associated with an upper knee chassis (10) and a brake member (34) associated with a shin carrier (18). The knee chassis is mounted on a posterior end portion (14P) of a resiliency biased activation arm (14) which pivots on the carrier (18). To provide a mechanical advantage in the brake action, a circumferential portion of the brake disc (32) is tapered, and the brake member (34) has a correspondingly tapered channel which receives the circumferential disc portion. The arrangement of the brake members (32, 34) and their mounting on the shin carrier (18) is such that substantial release of frictional engagement of the brake members can be substantially achieved even when a knee flexion moment is applied to the joint.