It is approximately the size and shape of a cashew. The scaphoid
is the largest bone of the proximal row. It is situated at the
radial side of the carpus, its long axis being from above
downward, lateralward, and forward. The etymology derives from
the Greek skaphe which means "a boat," and the Greek eidos which
means "form". The inferior surface, directed downward,
lateralward, and backward, is also smooth, convex, and
triangular, and is divided by a slight ridge into two parts, the
lateral articulating with the greater multangular, the medial
with the lesser multangular. On the dorsal surface is a narrow,
rough groove, which runs the entire length of the bone, and
serves for the attachment of ligaments. The volar surface is
concave above, and elevated at its lower and lateral part into a
rounded projection, the tubercle, which is directed forward and
gives attachment to the transverse carpal ligament and sometimes
origin to a few fibers of the Abductor pollicis brevis. The
lateral surface is rough and narro