Dance Anatomy & Kinesiology

The Upper Extremity 413

goes into full extension, the olecranon process moves

into a large indentation on the back of the lower

humerus (olecranon fossa).

The bony configuration of the elbow joint makes

it more stable than the shoulder. In addition, the

paired articulations of the elbow joint are encased

in a joint capsule that is thickened by various liga-

ments, including medial (or ulnar) and lateral (or

radial) collateral ligaments, to add greater joint

stability (figure 7.38). The ulnar collateral ligament

is particularly key for stabilizing the elbow joint, and

its medial location allows it to resist valgus stress

associated with lifting heavy objects or the support

of body weight. Many muscles of the elbow and the

extrinsic muscles of the hand that cross the elbow

joint have lines of pull that also provide consider-

able joint stability, in addition to joint movement

(Kreighbaum and Barthels, 1996).

Alignment of the Elbow

As with the knee, the elbow can be hyperextended

and can vary in its angulation. An understanding of

FIGURE 7.36 Bones and bony landmarks of the right elbow joint. (A) Anterior view, (B) posterior view.

these deviations can help with achievement of the

desired dance aesthetic.

Carrying Angle

The trochlea extends more distally than the capitu-

lum. Hence in anatomical position with the elbow

extended and forearm supinated, the forearm deviates

slightly laterally relative to the humerus. This angula-

tion is termed the carrying angle, or cubital angle, of

the elbow (figure 7.39). Some have hypothesized that

this angle functions to keep the hands from hitting

the hips when a person is carrying something with

the elbows by the sides, hence its name. The carrying

angle varies markedly between individuals and tends

to be greater in females versus males, and greater

in adults versus children (Goldman and McCann,

1997). Normal values are considered to be 10° to 25°

for females and 5° to 15° for males when the elbow is

extended in anatomical position (Frankel and Nordin,

1980; Magee, 1997). An increase in this angle above

normal due to greater lateral deviation of the forearm

is termed cubitus valgus, while a decrease in this angle

below norms is called cubitus varus.

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