At the distal end of the ulna, its knoblike
laterally with a notch of the radius (ulnar notch) and with a
disc of F brocartilage inferiorly (F g. 7.44). This disc, in turn,
joins a wrist bone (triquetrum). A medial
the distal end of the ulna provides attachments for ligaments
of the wrist.
The hand is made up of the wrist, palm, and F ngers. The skel-
eton of the wrist consists of eight small
bound in two rows of four bones each. The resulting compact
mass is called a
pus). The carpus is rounded on
its proximal surface, where it articulates with the radius and
with the F brocartilaginous disc on the ulnar side. The carpus
is concave anteriorly, forming a canal through which tendons
and nerves extend to the palm. Its distal surface articulates
with the metacarpal bones.
names the individual
bones of the carpus.
one in line with each F
form the framework of the palm or
pus) of the hand. These bones are cylindrical, with
rounded distal ends that form the knuckles of a clenched
wrenchlike opening, the
that articulates with the trochlea of the humerus. A pro-
cess lies on either side of this notch. The
located above the trochlear notch, provides an attachment
for the muscle (triceps brachii) that straightens the upper
limb at the elbow. During this movement, the olecranon pro-
cess of the ulna F ts into the olecranon fossa of the humerus.
just below the trochlear
ts into the coronoid fossa of the humerus when the
Right humerus. (
) Anterior surface. (
) Posterior surface.
Many a thirtyish parent of a young little leaguer or softball player
becomes tempted to join in. But if he or she has not pitched in many
years, sudden activity may break the forearm. Forearm pain while
pitching is a signal that a fracture could happen. Medical specialists
advise returning to the pitching mound gradually. Start with twenty
pitches, five days a week, for two to three months before regular
games begin. By the season’s start, 120 pitches per daily practice ses-
sion should be painless.