Download 2. THE SHOULDER GIRDLE 2.1 Function Unlike the pelvic girdle

2. THE SHOULDER GIRDLE
2.1 Function
Unlike the pelvic girdle, the shoulder girdle is a light and mobile structure and has the
ability to move on the chest wall under the control of several large muscles. Its
functions are:
SHOULDER GIRDLE
 to suspend the arm from the axial skeleton, and
 to participate in moving the arm and so position the hand in space
2.2 Structure
The shoulder girdle (Figure 29) is made up of two bones: the clavicle and scapula.
These two bones are joined together where the lateral end of the clavicle meets the
acromion process of the scapula. You can feel this bony process and the indentation of
the joint at the point of your own shoulder. The shoulder girdle is suspended from the
chest wall by a joint between the sternum and the medial end of the clavicle. This joint
is the only bony attachment of the shoulder girdle to the rest of the skeleton.
coracoid process
clavicle
acromion
process
scapula
humerus
FIGURE 29. THE BONES OF THE SHOULDER GIRDLE.
The remainder of the stability of the shoulder girdle is due to large muscles from the
chest wall and neck which suspend the clavicle and scapula (Figure 30). In particular
the trapezius muscle suspends the clavicle and scapula and the serratus anterior
secures the scapula to the chest wall.
trapezius
acromion
process
deep muscles
suspending the
scapula
FIGURE 30. POSTERIOR VIEW OF THE SHOULDER GIRDLE.
Unit 2 - Regional Anatomy
20
STERNUM