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Published on Aug 3, 2007
Movement of the Joints
Movement of the body's skeleton is made possible by a number of body parts working together including the joints. A hinge joint at the elbow allows the arm to bend and extend. The condylar joint at the knee gives similar movement plus some rotation. Mobile ellipsoid joints between the fingers and palm of the hand allow circular movements but no rotation. Ball-and-socket joints, like the one at the shoulder, give maximum freedom of movement. At the other extreme, plane joints between the toe bones permit only a small degree of gliding movement and the pivot joint between the two cervical vertebrae-the atlas and the axis-merely provides rotation of the head. The saddle joint at the ankle is almost as mobile as the shoulder joint, but rotation is far more limited.