Upper limb: forearm and hand II

Bones of the Hand
There are eight carpal bones, made up of two rows of
four (Figs. 9.51 and 9.52). The proximal row consists of
(from lateral to medial) the scaphoid, lunate, triquetral,
and pisiform bones. The distal row consists of (from lateral
to medial) the trapezium, trapezoid, capitate, and
hamate bones. Together, the bones of the carpus present
on their anterior surface a concavity, to the lateral and
medial edges of which is attached a strong membranous
band called the flexor retinaculum. In this manner, an
osteofascial tunnel, the carpal tunnel, is formed for the
passage of the median nerve and the flexor tendons of the
fingers.
The bones of the hand are cartilaginous at birth. The
capitate begins to ossify during the first year, and the others
begin to ossify at intervals thereafter until the 12th year,
when all the bones are ossified.
A detailed knowledge of the bones of the hand is
unnecessary. The position, shape, and size of the scaphoid
bone, however, should be studied, because it is commonly
fractured.
The ridge of the trapezium and the hook of the
hamate should be examined.