Dance Anatomy & Kinesiology

The Upper Extremity 399

with scapular adduction and downward rotation;
and glenohumeral external rotation is linked with
scapular adduction, while glenohumeral internal
rotation is linked with scapular abduction. Depend-
ing on the relationship to gravity and what types of
external forces are present, these movements may
be performed concentrically by the muscle(s) with
the associated action (see table 7.4) or controlled
eccentrically by the muscles that tend to produce the
opposite motion. For example, when one is raising a
weight to the side (shoulder abduction), the upward
rotation occurs from synergistic concentric contrac-
tion of the upward rotators of the scapula. However,
when the weight is lowered (shoulder adduction),
the downward rotation of the scapula tends to be
produced by gravity, and eccentric contraction of
the upward rotators of the scapula works to control
the downward rotation.
When the position changes from upright, things
get more complex; and it is important to consider
what effect gravity will have and which scapular
muscles will have to work to stabilize the scapulae.
For example, during a push-up, gravity tends to make
the scapulae come together (scapular adduction),
and the scapular abductors have to work to keep the
scapulae in the desired position. In other cases, dif-
ferent types of external resistance such as the floor,
a partner, or strength training apparatus influence
necessary scapular muscle recruitment.
While some of these linked motions, such as
upward rotation of the scapula, are necessary to
allow high degrees of shoulder flexion or abduction,

other movements are less predictably linked and

can be shaped by individual posture and movement

patterns. In dance, these movements are some-

times consciously biased to meet a given aesthetic.

For example, some schools of dance may prefer a

more open position of the arms with slight scapular

adduction, while others may prefer a “wider back”

with a neutral position or even slight abduction of

the scapula.

Influence of Shoulder Rotation on Abduction

In raising the arm to the side (shoulder abduction),

range is also facilitated by using external rotation

to position the humerus (Concept Demonstration

7.3). During the final 90° of abduction, this external

FIGURE 7.22 Upward rotation of the scapula accompa-
nying elevation of the arm.

FIGURE 7.23 The scapulohumeral rhythm with shoul-

der abduction.

TABLE 7.3 Linked Movements of the Scapula

That Accompany Movements of the Humerus

at the Shoulder Joint

Movement of humerus Movement of scapula

Flexion Abduction and upward rotation

Extension Adduction and downward rotation

Abduction Upward rotation

Adduction Downward rotation

Medial rotation Abduction

Lateral rotation Adduction

Hyperextension Elevation

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