The lunate bone is one of the proximal carpal bones that form the wrist. The name arises from the Latin [luna], meaning "moon". The lunate bone has a deep concavity and crescent-like shape, resembling a crescent moon. This bone is also known as the "semilunar bone" or the os lunatum.
The lunate bone has six surfaces (as a die). It articulates with the scaphoid bone by way of a strong ligament, the scapholunate interosseous ligament. This ligament has several components. Besides the scaphoid bone, the lunate bone articulates with the radius, capitate, hamate, and the triquetrum.
The accompanying image shows the anterior (volar) surface of the wrist. Click on the image for a larger picture.