Pivot joint in rotating an arm inward). When rotating the forearm, these movements are typically called pronation and supination. In the standard anatomical position, the forearms are supinated, which means that the palms are facing forward, and the thumbs are pointing away from the body. In contrast, a forearm in pronation would have the palm facing backward and the thumb would be closer to the body, pointing medially. Examples of a pivot joint include: In contrast, spherical joints (or ball and socket joints) such as the hip joint permit rotation and all other directional movement, while pivot joints only permit rotation. Pivot
Floating hinge Floating hinge A floating hinge is a hinge that, while able to behave as a normal hinge, enables one of the objects to move away from the other - hence float. In effect the hinge allows for two parallel axes of rotation, one for each object joined by the hinge, and each axis can be moved relative to the position of the other. Floating hinges are used in flatbed scanners designed to scan thick objects such as books. A sheet of paper is placed on the glass, and the cover is lowered over it; the glass, the paper, and the