Thoracic Cage Flashcards
What is the thoracic cage composed of?
- thoracic vertebrae posteriorly
- ribs laterally
- sternum anteriorly
- costal cartilages
What are the general functions of the thoracic cage?
- Supports shoulder girdle and upper limbs
- Protects viscera in thoracic cavity and upper abdominal
How many ribs do humans have?
What is the structure of a rib?
Head: posterior end; articulates with vertebrae
Neck
Tubercle: articulates with vertebra
Shaft: main protion; long and slender
Costal cartilage: hyaline cartilage; connects rib to sternum
What are the structures of the sternum?
- articulates with costal cartilages and clavicles
3 parts:
manubrium
- suprasternal/jugular notch
- clavicular notch
- body
- xiphoid process
What are the general characteristics of ribs?
The first seven rib pairs are called true ribs and they join the sternum directly by their costal cartilages.
The remaining five pairs are called false ribs because their cartilages do not reach the sternum directly - instead the upper three false ribs join cartilages of the seventh rib, and the lower two rib pairs do not attach to the sternum.
The lower two pairs are called floating ribs
What are the general structures of a rib?
- A typical rib has a long slender shaft that curves around the chest and slopes downwars, on the posterior end is an enlarged head by which the rib articulates with a facet on the body of its own vertebra and with the body of the next higher vertebra.
The neck of the rib is flattened, lateral to the head, where ligaments attach.
A tubercle, close to the head of the rib articulates with the transverse process of the vertebra
What are the general characteristics of the sternum?
- the sternum, or breastbone, is located aong the midline in the anterior portion of the thoracic cage.
- It is a flat, elongated bone that develops in three parts - an upper manubrium, a middle body, and a lower xiphoid process that projects downward
