1. Thorax
Ribs and Sternum

2. Bony Thorax Include Thoracic vertebrae dorsally Ribs laterally
Sternum and costal cartilage anteriorly
Function
Secure rib to sternum
Protective cage around vital organs
Supports shoulder girdles and upper limbs
Provides attachment points for muscles of back, chest, and shoulder
Intercostal spaces provide attachment for intercostal muscles that lift and depresses chest during breathing

3. Sternum Lies anterior midline of thorax
Resembles knife blade, flat, about 15 cm (6in) long
Made from 3 fused bones
Manubrium (superior)
clavicular notches articulates with clavicles and first two pairs of ribs
--Body (midline)
forms the bulk of sternum
articulates with second to seventh rib
Xiphoid process (inferior)
Attachment site for abdominal muscles

4. Ribs 12 Pair in males and females
Each rib articulate with both the body and the transverse process of its corresponding thoracic vertebra
From vertebral attachment, rib curve outward, then forward and downward

5. True Rib 1st 7 pairs Join costal cartilage anteriorly
Connect directly to sternum

6. False rib Last 5 pairs of ribs attach indirectly to sternum
Last two pairs of false ribs called floaters because they do not attach to sternum at all