Abstract: A knee prosthesis is provided which forces the femur and tibia apart on twisting of the knee so that weight applied through the knee has an untwisting action. A tibial member and an intermediate member are journalled together by peg which fits into socket. Opposite handed helical surfaces cam the members apart when the knee is twisted. A knee hinge is defined by the intermediate member and a female member.

Abstract: A human joint implant, for example a knee prosthesis has a working part formed with a stub having a conical profile that snap-fits into a stem that forms an anchorage in a bone cavity. The stub may carry a stud at its end that is a snap-fit into a ferrule. A flanged sleeve fits between the stub and a conical socket part of the stem.

Abstract: An improved knee prosthesis of the four bar kind employing modified geometry of its links permitting the available degree of flexion to be increased to 143.degree.. A resilient leaf spring provides for extension bias at low angles of flexion, and biases the joint towards its fully flexed position at high angles of flexion. An improved lock for the joint is also provided.

Abstract: An artificial hand comprises a palm member and thumb and finger members movable towards and away from one another by an actuator. A cosmesis covering the actuator has a touch sensor in a cavity of the cosmesis that deforms on contact with an object. The cavity is connected via a conduit with a microphone that picks up pressure waves resulting from stick/slip motion of the object along the surface of the cosmesis. The distance between the thumb and finger members is determined by a position sensor, and muscle sensor means responsive to contraction of first and second muscle groups supplies position and control signals in first and second channels.

Abstract: A joint for demountably clamping a tubular member into a main bore in a socket comprises an auxiliary bore directed perpendicular to the axis of the main bore and intersecting it over a small arc and first and second collets that fit in the auxiliary bore. Part cylindrical bearing faces on the collets are shaped to conform to the curvature of the tubular member. A clamping bolt urges the collets together so that they press on the tubular member and retain it in the socket. Preferably a reinforcing insert fits the end of the tubular member and has a disc or annulus that registers with the collets to resist compressive loads on the tube.

Abstract: An inflatable lower limb prosthesis comprises an outer cover of relatively inextensible material defining the shape of a leg prosthesis and having a pad of rigid material at its lower end defining the shape of a foot. An inner member of independently inflatable compartments welded together comprises a shin compartment contacting the rigid pad and of upwardly convergent profile, an inner spacer compartment between the upper end of the shin compartment and the patient's stump and an annular socket compartment that surrounds the patient's stump and extends downwardly in overlapping relation around the upper end of the shin compartment to resist bending of the prosthesis at the false joint at the patient's stump.

Abstract: A knee joint for an artificial limb comprises a knee member having a part spherical convex lower surface pivoted about an axis to a knee housing having a part spherical concave upper surface conforming to the curvature of the knee member. A spring loaded plunger directly connected to a release cable runs on a guideway on the curved surface of the knee housing when the knee is flexed and in the unflexed position latches into a seating to prevent knee flexion. A collet fixing is preferably used to attach the shin tube into a socket depending from the knee housing without the need to drill the tube.

Abstract: The angular relation of a Sach foot to a shin may be adjusted during assembly to provide a desired heel height so that one type of Sach foot may be stocked for each shoe size and adapted for different heights of heel. The connecting bolt passes through a rotatable trunnion transverse to the length of the foot and is pivotable between fore and aft limits, and material is removed from the confronting surfaces of the foot and shin during fitting or packing material is inserted between them to effect such angular displacement.

Abstract: An artificial leg of the kind in which the shin portion and the knee portion are shaped from a block of wood or similar solid material, has the knee and shin portions connected by pairs of front and rear links, the effective length of the front links being less than that of the rear links and the connections between the links and the knee and shin portions being positioned so as to form an articulation of which the instantaneous center of rotation lies upon an ascending curve for a predetermined angle of relative rotation between the two portions of the leg from the fully extended position. The resultant joint provides a stable weight support until it has been flexed through the predetermined angle and is thereafter capable of flexure through more than a right angle.

Abstract: A prosthetic wrist fitting for attachment to a fore-arm termination comprises a socket with an internally toothed ring surrounding its mouth and a complementary plug having an externally toothed ring so that the plug may be engaged with the socket in angularly adjusted relation. The plug is maintained in the socket against ejection by a spring by engagement of a keep ring slidable across the socket bore and engaging a groove in the plug. The internally toothed ring may be rotatable relatively to the body socket axis and provided with a number of over-ridable detents so that the plug may be turned through angular steps without removal from the socket. A manually operated catch retains the plug in any selected one of these adjusted steps.

Abstract: The angular movement of a knee joint of the kind comprising a four bar linkage is controlled by the frictional engagement of a shaft, pivoted at one end to one of the links, with a pivotable plastics bush located between the ends of another link. The plastics bush may be tightened around the shaft to adjust the frictional restraint on the movement of the joint.