426 Dance Anatomy and Kinesiology
surface of the forearm. This motion is usually
referred to with the specialized term radial deviation.
The opposite motion of bringing the medial side of
the hand (little finger) closer to the medial forearm
is termed adduction or ulnar deviation.
However, these movements at the radiocarpal
joint or wrist joint do not occur in isolation but rather
also incorporate the midcarpal joint. The term mid-
carpal joint refers to the joint between the proximal
and distal row of carpals. As with the foot, this “joint”
actually incorporates several joints, and in the hand
these joints are gliding in nature. However, the slight
gliding movements of the midcarpal joint contribute
additional range of motion and are automatically
linked to movements of the radiocarpal joint.
Moving distally from the midcarpal joint, there are
many additional joints that are important for allowing
the complex movements of the hand. As with the feet,
these joints are often named according to the bones
that compose the joints, making learning the names
easier and logical. The joints between the carpals and
metacarpals 2 through 5 termed carpometacarpal
joints are classified differently in different texts,
but commonly as gliding joints (Hall, 1999; Magee,
1997). These joints are linked by strong ligaments
such that almost no movement is allowed for joints
2 and 3, slight flexion is allowed with 4, and more
flexion with 5. This arrangement facilitates the abil-
ity to cup the palm, which when combined with the
motions of the first metacarpal facilitates the essen-
tial ability to grasp objects.
In contrast to the other carpometacarpal joints,
the first carpometacarpal joint is a biaxial saddle joint,
which allows for the specialized movement of opposi-
tion of the thumb to the fingers used to “grip” objects.
Opposition refers to the ability to bring the palmar tip
of the thumb toward the palmar surface of the other
digits, and reposition is the reverse movement. This
specialized movement of opposition is facilitated not
only by the presence of this saddle joint and the cup-
ping of the palm but also by the orientation of the joint
relative to the other fingers. Unlike what occurs with
the large toe in the foot, the thumb is separated from
the second finger more widely than the other fingers
are separated from one another and is turned on its
axis so that it faces a plane perpendicular to that of
the other fingers (Hamilton and Luttgens, 2002). In
addition to the specialized movement of opposition-
reposition, fundamental movements of the thumb
include flexion-extension and abduction-adduction,
shown in figure 7.48. Note that due to the rotated
orientation of the thumb, these movements of the
thumb occur in a plane perpendicular to the plane
in which they classically occur. So, extension refersto a lateral movement of the thumb away from the
index finger, while flexion is a return movement
from extension; hyperflexion entails movement of
the thumb across and parallel to the palm (i.e., in an
almost frontal vs. sagittal plane). Abduction refers to
movement of the thumb forward and away from the
second finger in a plane perpendicular to the palm,
while adduction would be the return movement to
anatomical position (i.e., in an approximate sagittal
vs. frontal plane). Given these movement descrip-
tions, opposition can be seen as a combination of
abduction and hyperflexion.
Moving further distally, the joint between the
distal end of the first metacarpal bone and adjacent
proximal phalange, termed the metacarpopha-
langeal joint, is a hinge joint allowing flexion and
extension. However, the metacarpophalangeal joints
for metacarpals 2 through 5 are biaxial condyloid
joints—allowing flexion, extension, and slight abduc-
tion and adduction of the fingers. Flexion refers to
bringing the anterior surface of the finger toward the
palmar surface of the hand, while extension is the
reverse movement of bringing the anterior surface
of the finger away to return to anatomical position
or slightly beyond (hyperextension) as seen in figure
7.48. Abduction and adduction occur relative to the
middle finger, and abduction refers to movement of
the second (index), fourth (ring), and fifth (little)
fingers away from the third (middle) finger. The
reverse motion of bringing the fingers back toward
the middle finger is termed adduction. The side-
to-side movements of the third finger are termed
radial and ulnar flexion rather than abduction
and adduction. Comparable to the situation with
the wrist, radial flexion refers to lateral movement
of the third finger toward the radial side of the
forearm while ulnar flexion refers to medial move-
ment of the third finger toward the ulnar side of
the forearm. Lastly, the joints between all adjacent
phalanges, the interphalangeal joints, are uniaxial
hinge joints—allowing flexion and extension of
the digits of the fingers and thumb. These move-
ments of the fingers are comparable to those of the
metacarpophalangeal joints, with flexion referring to
approximating anterior surfaces of the digits of the
fingers or bringing the anterior surface of the digits
toward the palmar surface of the hand (or both).
Extension would involve the reverse movement. In
general, movements toward the palm of the hand
(flexion) are of a larger range than movements
toward the dorsum of the hand (extension).
Numerous strong ligaments interconnect the
bones and reinforce the capsules of the many joints
in the wrist-hand complex. Many muscles also act to