Abstract: An alignment device is provided for an artificial limb and comprises first and second end plates fastenable to respective upper and lower parts of the limb in a predetermined angular and axial position. A flexible sleeve fastened between the end plates forms therewith an internal cavity for containing a body of settable fluid. When the fluid body is in a flowable state relative movement between upper and lower parts of the limb during alignment thereof are accommodated by flexion of the sleeve. When the fluid body is in a solidified state it establishes a rigid mechanical linkage between the end plates, thereby preventing relative movement of the upper and lower parts. Angular alignment between an end plate and an adjoining part of the limb is provided by pegs on one of said parts engaging sockets on the other of said parts.

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: A hip joint for a prosthetic leg has first and second members pivoted together by a pin through the first member. The pin includes an outer spool-like spindle roatable in a bearing in said first member and an inner spool-like spindle rotatable in a bearing in the outer spindle and carrying pivots for the second member. The inner spindle has an axis skew to the outer spindle so that firstly an angle may be set between the pivot axis of the joint and said first member by adjusting the relative angular positions of the inner and outer spindles and secondly an attitude of said pivot axis may be set by adjusting the angular position of the outer spindle relative to the first member. The hip joint may have a buffer assembly that contacts an abutment on the first member at a contact line or plane to define a rearward limit of swing of the second member.

Abstract: A shift device for a prosthetic limb comprises: first and second plates having adjoining flat faces in sliding contact. Spaced parallel ribs on an outer face of each plate define a slideway. Guides in the slideways of the first and second plates enable the plates to move generally at right angles to one another. The guides include first and second guide bars slideably received in the respective slideways. One or more longitudinal slots in each slideway permit limited relative translational movement of the plates. Clamping screws pass through each slot of each of the first and second plates into the guide bar in the slideway of the other plate. The clamping screws are releasable to allow relative movement of the plates and on re-tightening immobilize the plates.

Abstract: A compact and lightweight knee joint for a prosthetic leg that can be locked or released with low operating forces comprises upper and lower members interconnected by a pin at a posterior location. A latch pivoted to one of the members for rotation about a vertical axis releasably locks into a recess in the other member to hold the joint in its extended position. The upper member has depending cheeks between which a head of the lower member is received. Adjoining horizontal faces of the upper and lower members are planar and a pad of elastomeric material attached to one of the planar surfaces serves as an extension stop buffer. The latch is blade-like and of bell-crank shape. It fits into slots in the anterior edge of each cheek and is pivoted in one of the slots with an anterior lever thereof spanning between the slots and with a latch head thereof fitting into the other slot. A cable release is fitted to the medial/lateral lever for release of the latch.

Abstract: A first member of an artificial limb such as a tube socket has a generally rhombic flange formed with throughholes grouped into an anterior-posterior pair and a medial/lateral pair spaced at 90 degree intervals about the axis of socket. The lower face of the flange carries a ball formation of a ball and socket articulation. A second member in the form of ankle attachment plate has a concave seat that accepts the ball and threaded bores conforming to the through holes. The first and second members are held together by clamping screws received in the bores that fit onto washers having spherical lower faces that articulate on seats. The resulting alignment device is simple to manufacture and preserves angular position when an adjacent pair only of the clamping screws are removed. A similar alignment device having a cylindrical projection articulating in a cylindrical seat under the control of a single pair of clamping screws provides for heel height adjustment.

Abstract: A prosthetic foot comprises a hollow elastomeric cosmesis having a relatively large internal space, a keel of relatively stiff or rigid material, and a stiffener of glass reinforced plastics fitted between keel and instep region of the cosmesis. Front and rear snubbers extend from keel and front and rear stiffeners being portions of stiffener extend from under the keel with radiused ends resting on the sole of the cosmesis. During ambulation the stiffeners provide a primary path by which ground reaction is transmitted to the keel, but ground reaction bringing the stiffeners into contact with the snubbing means is transmitted to the keel via an overload path through the snubbing means.

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: 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.

Abstract: The invention provides an alignment device for use between a tube socket and a weight-bearing element of an artificial limb in which a desired angular relationship set by jacking screws and maintained by a controlled degree of friction between concentric part-spherical surfaces is maintainable despite the unlocking of clamping screws applying force between the said surfaces.