Dance Anatomy & Kinesiology

The Upper Extremity 375

angle of the scapulae ends before it creates a true
angle in an indented area termed the glenoid fossa
(G. glenoeides, socket of joint) or glenoid cavity. Just
medial to this glenoid cavity, a large, beaklike pro-
cess projects forward from the scapulae termed the
coracoid process (G. korakodes, like a crow’s beak).
This process is a site for attachments of key muscles
and ligaments for the shoulder and shoulder girdle.
With their positioning above the glenoid cavity, the
acromion process and coracoid process also help
protect the shoulder joint.
The humerus is a long bone with a cylindrical
body that changes in form at both ends and is quite
parallel in structure to the femur (figure 7.3). At
the proximal end, the humerus expands to form
the rounded head, the medial portion of which
articulates with the glenoid cavity to form the shoul-
der joint. Slightly distal to this articular surface and
on the anterior aspect of the humerus lie the more
medially placed lesser tubercle and the more later-
ally placed greater tubercle. The greater tubercle
can be palpated just below the acromion process
when the arm is hanging by the side in an inter-
nally rotated position. The slight narrowing of the
humerus between the articular surface of the head

of the humerus and the greater and lesser tubercles

is termed the anatomical neck of the humerus, while

the region where the head and tubercles join to the

body of the humerus is termed the surgical neck. The

lesser and greater tubercles are separated from each

other by a groove called the intertubercular sulcus or

groove. The tendon of the long head of the biceps

brachii muscle lies within this groove. You can gener-

ally palpate this groove with two fingers below the

acromion process when your arm is fully externally

rotated with the elbow by your side. If you follow the

intertubercular groove down the arm, its lateral por-

tion leads to a roughened prominence about half-

way down the humerus called the deltoid tuberosity

(the site of attachment for the distal deltoid muscle).

The landmarks of the distal end of the humerus will

be described later with the elbow joint.

Joint Structure and Movements of the Shoulder Girdle.

The shoulder girdle can be pictured as an incom-

plete ring formed by the two clavicles and two

scapulae (figure 7.4). Anteriorly, the paired clavicles

FIGURE 7.2 Bony landmarks of the scapula (right scapula). (A) Costal surface, (B) dorsal surface.

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