Finger joint prosthesis esp. for main hand to finger joint

摘要

The artificial joint consists of two rods (1,2) and a ball joint. The cylindrical outer surfaces of the rods have linear grooves. The rods are inserted in the bone cavities. One rod, which is inserted in the finger, has a flange (3) which is at right angles to its centreline. The other rod has a flange (4) which lies at an angle of approximately 45 degrees to its centreline. A ball joint (5,8) is mounted between the flanges (3,4). As the flange on one rod lies at an angle, the centre of rotation of the ball joint is off-set from the centreline of the rod. The joint consists of a part spherical cup (8) in which a part sphere (5) is mounted. A central sphere, which is mounted on a pin in the cup (8), retains the part sphere (5). The pin also acts as a stop to limit the movement of the ball joint.