Artificial organ almost always preceded by extensive experiments with animals. Initial testing in humans is frequently limited to those either already facing death or who have exhausted every other treatment possibility. Artificial arms and legs, or prosthetics, are intended to restore a degree of normal function to amputees. Mechanical devices that allow amputees to walk again or continue to use two hands have probably been in use since ancient times, the most notable one being the simple peg leg. Since then, the development of artificial limbs has progressed rapidly. New plastics and other materials, such as carbon fiber have allowed artificial limbs
The King of Limbs made Donwood think of "immense multicoloured cathedrals of trees, with music echoing from the branches whilst strange fauna lurked in the fog". Donwood and Yorke drew trees with eyes, limbs, mouths, and familiars, creating "strange, multi-limbed creatures that are neither malevolent or benevolent", inspired by Northern European fairy tales. For the special "newspaper" edition of "The King of Limbs", Donwood wanted to create something "in a state of flux". He chose newspaper, which fades in sunlight, for "its ephemeral nature"; this reflected the album's nature themes, mirroring the natural decay of living things. To design the newspaper, Donwood took inspiration