Functions
Positioning the hand
Unlike the lower limb (which is used for support, stability, and locomotion), the upper limb is highly
mobile for positioning the hand in space.
The shoulder is suspended from the trunk predominantly by muscles and can therefore be moved
relative to the body.
Movements of the scapula are rotation and sliding (protraction and retraction) on the thoracic wall.
These movements change the position of the glenohumeral joint (shoulder joint) and extends the
reach of the hand.
Figure 7.1. Movements of the scapula. A. Rotation. B. Protraction and retraction.
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