306 Dance Anatomy and Kinesiology
of the toes would involve movement of the toes away
from the second toe, while adduction would involve
bringing the toes back toward the second toe.
Lastly, the joints between adjacent phalanges—the
interphalangeal (IP) joints—are hinge joints. They
allow flexion and extension of the toes. Flexion refers
to bringing the plantar surfaces of the digits closer
together such as when curling the toes under, while
extension refers to decreasing the flexion of the
digits, or straightening the toes.The Composite Movements
of Pronation and SupinationDue to the oblique orientation of the axes of the
ankle, subtalar joint, and transverse tarsal joints and
the close structural interrelationship of many of these
joints, an isolated movement of an individual joint in
a single plane is rare or even not possible, depending
on the joint. In functional movement, many motions
of the foot are composites, involving joints in the rear-
foot, midfoot, and forefoot in multiple planes. Two
particularly important examples of such movements
are pronation and supination. When bearing weight,
pronation can be described as a composite movement
that involves dorsiflexion (primarily from the ankle),
eversion (primarily of the rearfoot), and abduction
(primarily of the forefoot), while supination involvesthe opposite motions of plantar flexion, inversion,
and adduction (Hall, 1999). As will be discussed later
in this chapter, these combination movements serve
very important functions in weight-bearing activities
such as walking, running, and dancing.Special Structures of the Ankle and Foot
There are many specialized structures associated
with the ankle and foot that enhance their function.
A description of some of these structures that are
particularly important follows.Plantar FasciaA special very strong and inelastic band of connec-
tive tissue called the plantar fascia (L. plantaris,
relating to the sole of the foot + sheet of fibrous
tissue) is located in the sole of the foot as shown in
figure 6.7. It attaches from the heel (underside of
the calcaneus) and runs forward, fanning out and
dividing into slips that attach to the sheaths of the
flexor tendons of the toes, underside of the proxi-
mal phalanges, and ligamentous structures near the
heads of the metatarsals. The plantar fascia is covered
only by fat and the skin, and can be readily palpated
on the underside of the medial arch of the foot when
the foot and toes are simultaneously dorsiflexed.Foot Supination and Pronation
Stand in a parallel first position with your feet facing straight ahead and your knees slightly bent.- Identifying foot inversion and eversion. Without changing the position of your knee or the facing
of your forefoot, slightly lift the inner border of the heel and arch of one foot, thinking of rotating about
the longitudinal axis of the foot running through the second toe. This motion is inversion of the foot.
Now, slightly lift the outer border of the heel and foot. This motion is eversion of the foot. Notice that
the amount of possible movement of the foot is small if the knee remains facing straight ahead and
is not allowed to move inward or outward relative to the foot. - Identifying foot supination. While still standing in first position, rock your body weight back onto
your heels so that the front of your foot can move. Keeping your weight back, carefully and slowly lift
the inner borders of your feet and notice how the front of your feet tend to point very slightly inward.
The position you are in reflects all three elements of foot supination: plantar flexion (relative), inver-
sion, and forefoot adduction. - Identifying foot pronation. Returning to your original first position, bend your knees (plié) and
allow your knees to fall inside your feet as you carefully lift the outer borders of your feet. Notice how
the front of your feet point very slightly outward. The position you are in reflects all three elements of
foot pronation: dorsiflexion, eversion, and forefoot abduction.